SEC Form 424B5 filed by Estrella Immunopharma Inc.

Filed Pursuant to Rule 424(b)(5)

Registration No. 333-283770

PROSPECTUS SUPPLEMENT

(To the Prospectus Dated December 19, 2024)

Estrella Immunopharma, Inc.

4,063,290 Shares of Common Stock

1,000,000 Pre-Funded Warrants to Purchase Shares of Common Stock

1,000,000 Shares of Common Stock Underlying Pre-Funded Warrants

We are offering 4,063,290 shares of our common stock, par value $0.0001 per share, at a public offering price of $1.58 per share. We are also offering to each purchaser whose purchase of shares of our common stock in this offering would otherwise result in the purchaser, together with its affiliates and certain related parties, beneficially owning more than 4.99% (or, at the election of the holder, 9.99%) of our outstanding shares of common stock immediately following consummation of this offering, the opportunity to purchase, if the purchaser so chooses, 1,000,000 pre-funded warrants to purchase shares of common stock, or the pre-funded warrants, in lieu of shares of common stock. Each pre-funded warrant will be exercisable for one share of our common stock. The purchase price of each pre-funded warrant will equal the price per share of common stock being sold to the public in this offering, minus $0.00001, and the exercise price of each pre-funded warrant will be $0.00001 per warrant share. The pre-funded warrants will not be listed on the Nasdaq Capital Market and are not expected to trade in any market; however, we anticipate that the shares of our common stock to be issued upon exercise of the pre-funded warrants will trade on the Nasdaq Capital Market. We are also registering the shares of common stock issuable upon exercise of the pre-funded warrants pursuant to this prospectus supplement.

In a concurrent private placement, we are also selling to the purchasers of our shares of common stock warrants, or private placement warrants, to purchase 7,594,935 shares of our common stock at an exercise price of $1.39 per warrant share. The private placement warrants and the shares of common stock issuable upon the exercise of such warrants are not being registered under the Securities Act of 1933, as amended, or the Securities Act, are not being offered pursuant to this prospectus supplement and the accompanying base prospectus and are being offered pursuant to the exemption provided in Section 4(a)(2) of the Securities Act and Rule 506(b) promulgated thereunder. The private placement warrants are immediately exercisable, and will expire five (5) years from the issuance date.

Our common stock is currently quoted on the Nasdaq Capital Market (the “Nasdaq”) under the symbol “ESLA”. The closing sales price of our common stock on January 5, 2026 was $1.33 per share.

As of January 5, 2026, the aggregate market value of our outstanding common stock held by non-affiliates (our “public float”) was approximately $34,806,399, based on 37,970,938 shares of common stock outstanding, of which 11,875,904 shares are held by non-affiliates, and a per share price of $2.9300 (the highest closing sales price of our common stock on the Nasdaq on November 6, 2025, which is within 60 days prior to the date of this filing). As of January 5, 2026, our public float was less than $75,000,000, as calculated in accordance with General Instruction I.B.1 of Form S-3. We have not offered and sold any securities pursuant to General Instruction I.B.6 to Form S-3 during the 12-calendar month period that ends on, and includes, the date of this prospectus supplement. Pursuant to General Instruction I.B.6 of Form S-3, in no event will we sell securities in a public primary offering with a value exceeding more than one-third of our public float in any 12-month period so long as our public float remains below $75,000,000.

Investing in our securities involves risks. You should carefully consider the risk factors under, and incorporated by reference in, “Risk Factors” beginning on page S-3 of this prospectus and the discussion of risk factors contained in our annual, quarterly and current reports filed with the Securities and Exchange Commission under the Securities Exchange Act of 1934, as amended, which are incorporated by reference into this prospectus, and in the other documents incorporated by reference herein, before making any decision to invest in our securities.

We have engaged Aegis Capital Corp., or the placement agent, to act as our exclusive placement agent in connection with this offering. The placement agent has agreed to use its best efforts to arrange for the sale of the securities offered by this prospectus supplement. The placement agent is not purchasing or selling any of the securities we are offering and the placement agent is not required to arrange the purchase or sale of any specific number or dollar amount of securities. We have agreed to pay to the placement agent the placement agent fees set forth in the table below, which assumes that we sell all of the securities offered by this prospectus supplement. There is no arrangement for funds to be received in escrow, trust or similar arrangement. There is no minimum offering requirement as a condition of closing of this offering. We will bear all costs associated with the offering. See “Plan of Distribution” on page S-10 of this prospectus supplement for more information regarding these arrangements.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.

The delivery to purchasers of the shares of common stock in this offering is expected to be made on or about January 6, 2026, subject to satisfaction of certain customary closing conditions.

Aegis Capital Corp.

The date of this prospectus supplement is January 6, 2026.

TABLE OF CONTENTS

PROSPECTUS SUPPLEMENT

PROSPECTUS

ABOUT THIS PROSPECTUS SUPPLEMENT

This prospectus supplement and the accompanying base prospectus are part of a registration statement that we filed with the Securities and Exchange Commission, or the SEC, utilizing a “shelf” registration process. From time to time, we may conduct an offering to sell securities under the accompanying base prospectus and a related prospectus supplement that will contain specific information about the terms of that offering, including the price, the amount of securities being offered and the plan of distribution. This prospectus supplement describes the specific details regarding this offering and may add, update or change information contained in the accompanying base prospectus. The base prospectus, dated December 19, 2024, including the documents incorporated by reference therein, provides general information about us and our securities, some of which may not apply to this offering. This prospectus supplement and the accompanying base prospectus are an offer to sell only the securities offered hereby, but only under circumstances and in jurisdictions where it is lawful to do so. We are not making offers to sell or solicitations to buy our securities in any jurisdiction in which an offer or solicitation is not authorized or in which the person making that offer or solicitation is not qualified to do so or to anyone to whom it is unlawful to make an offer or solicitation.

If information in this prospectus supplement is inconsistent with the accompanying base prospectus or the information incorporated by reference with an earlier date, you should rely on this prospectus supplement. This prospectus supplement, together with the accompanying base prospectus, the documents incorporated by reference into this prospectus supplement and the accompanying base prospectus and any free writing prospectus we have provided for use in connection with this offering, include all material information relating to this offering. We have not authorized anyone to provide you with different or additional information, and you must not rely on any unauthorized information or representations. You should assume that the information appearing in this prospectus supplement, the accompanying base prospectus, the documents incorporated by reference in this prospectus supplement and the accompanying base prospectus and any free writing prospectus we have provided for use in connection with this offering is accurate only as of the respective dates of those documents. Our business, financial condition, results of operations and prospects may have changed since those dates. You should carefully read this prospectus supplement, the accompanying base prospectus and the information and documents incorporated herein by reference herein and therein, as well as any free writing prospectus we have provided for use in connection with this offering, before making an investment decision. See “Incorporation of Certain Documents by Reference” and “Where You Can Find More Information” in this prospectus supplement and in the accompanying base prospectus.

This prospectus supplement and the accompanying base prospectus contain summaries of certain provisions contained in some of the documents described herein, but reference is made to the actual documents for complete information. All of the summaries are qualified in their entirety by the full text of the actual documents, some of which have been filed or will be filed and incorporated by reference herein. See “Where You Can Find More Information” in this prospectus supplement. We further note that the representations, warranties and covenants made by us in any agreement that is filed as an exhibit to any document that is incorporated by reference into this prospectus supplement or the accompanying base prospectus were made solely for the benefit of the parties to such agreement, including, in some cases, for the purpose of allocating risk among the parties to such agreements, and should not be deemed to be a representation, warranty or covenant to you. Moreover, such representations, warranties or covenants were accurate only as of the date when made. Accordingly, such representations, warranties and covenants should not be relied on as accurately representing the current state of our affairs.

This prospectus supplement and the accompanying base prospectus contain and incorporate by reference certain market data and industry statistics and forecasts that are based on independent industry publications and other publicly available information. Although we believe these sources are reliable, estimates as they relate to projections involve numerous assumptions, are subject to risks and uncertainties, and are subject to change based on various factors, including those discussed under “Risk Factors” in this prospectus supplement and the accompanying base prospectus and under similar headings in the documents incorporated by reference herein and therein. Accordingly, investors should not place undue reliance on this information.

INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE

The SEC permits us to “incorporate by reference” the information and reports we file with it. This means that we can disclose important information to you by referring to another document. The information that we incorporate by reference is considered to be part of this prospectus supplement, and later information that we file with the SEC automatically updates and supersedes this information. We incorporate by reference the documents listed below, except to the extent information in those documents is different from the information contained in this prospectus supplement, and all future documents filed with the SEC under Sections 13(a), 13(c), 14, or 15(d) of the Exchange Act (other than the portions thereof deemed to be furnished to the SEC pursuant to Item 9 or Item 12) until we terminate the offering of these securities:

(c) The Company’s Quarterly Report on Form 10-Q for the quarters ended March 31, 2025, filed with the SEC on May 14, 2025;

(d) The Company’s Quarterly Report on Form 10-Q for the quarter ended June 30, 2025, filed with the SEC on August 12, 2025;

(e) The Company’s Quarterly Report on Form 10-Q for the quarters ended September 30, 2025, filed with the SEC on November 12, 2025;

(f) The Company’s Current Reports on Form 8-K filed with the SEC on February 20, 2025, February 21, 2025, May 2, 2025, May 29, 2025, June 3, 2025, June 5, 2025, August 7, 2025, September 26, 2025, September 29, 2025, November 6, 2025 and December 4, 2025; and

(g) The description of the Company’s Common Stock contained in Exhibit 4.5 to the Transition Report (File No. 001-40608), including any amendment or report filed for the purpose of updating such description.

To the extent that any statement in this prospectus supplement is inconsistent with any statement that is incorporated by reference and that was made on or before the date of this prospectus supplement, the statement in this prospectus supplement shall supersede such incorporated statement. The incorporated statement shall not be deemed, except as modified or superseded, to constitute a part of this prospectus supplement or the registration statement. Statements contained in this prospectus supplement as to the contents of any contract or other document are not necessarily complete and, in each instance, we refer you to the copy of each contract or document filed as an exhibit to our various filings made with the SEC.

You may request a copy of these filings, at no cost, by writing or telephoning us at the following address or telephone number:

Estrella Immunopharma, Inc.

5858 Horton Street, Suite 370

Emeryville, California, 94608

Attn: Investor Relations

Phone: (510) 318-9098

RISK FACTORS

Investing in our securities involves a high degree of risk. Before investing in our securities, you should carefully consider the risks, uncertainties and assumptions contained in this prospectus supplement and also contained under the heading “Risk Factors” included in our Transition Report on Form 10-KT for the period ended December 31, 2024 filed with the SEC on March 25, 2025, as revised or supplemented by subsequent filings, which are on file with the SEC and are incorporated herein by reference, and which may be amended, supplemented or superseded from time to time by other reports we file with the SEC in the future. Our business, financial condition, results of operations and future growth prospects could be materially and adversely affected by any of these risks. In these circumstances, the market price of our common stock could decline, and you may lose all or part of your investment.

Risks Related to this Offering and Our Common Stock

As an investor, you may lose all of your investment.

Investing in our securities involves a high degree of risk. As an investor, you may never recoup all, or even part, of your investment and you may never realize any return on your investment. You must be prepared to lose all of your investment.

Because we will have broad discretion and flexibility in how the net proceeds from this offering are used, we may use the net proceeds in ways in which you disagree.

We intend to use the net proceeds from this offering for working capital and general corporate purposes. See “Use of Proceeds” for additional information. Accordingly, our management will have significant discretion and flexibility in applying the net proceeds of this offering. You will be relying on the judgment of our management with regard to the use of these net proceeds, and you will not have the opportunity, as part of your investment decision, to assess whether the net proceeds are being used appropriately. It is possible that the net proceeds will be invested in a way that does not yield a favorable, or any, return for us. The failure of our management to use such funds effectively could have a material adverse effect on our business, financial condition, operating results and cash flow.

The market price of our shares may be subject to fluctuation and volatility.

You could lose all or part of your investment. The market price of our common stock is subject to wide fluctuations in response to various factors, some of which are beyond our control. The market price for our common stock varied between a high of $3.15 and a low of $0.73 in the twelve-month period ended January 5, 2026. The market price of our shares on the Nasdaq Capital Market may fluctuate as a result of a number of factors, some of which are beyond our control, including, but not limited to:

There is no public market for the pre-funded warrants being offered by us in this offering.

There is no established public trading market for the pre-funded warrants, and we do not expect a market to develop. In addition, we do not intend to apply to list the pre-funded warrants on any national securities exchange or other nationally recognized trading system. Without an active market, the liquidity of the pre-funded warrants will be limited.

The pre-funded warrants in this offering are speculative in nature.

The pre-funded warrants offered hereby do not confer any rights of share of common stock ownership on their holders, such as voting rights, but rather merely represent the right to acquire shares of common stock at a fixed price. Specifically, commencing on the date of issuance, holders of the pre-funded warrants may acquire the shares of common stock issuable upon exercise of such warrants at an exercise price of $0.0001 per warrant share. Moreover, following this offering, the market value of the pre-funded warrants is uncertain and there can be no assurance that the market value of the pre-funded warrants will equal or exceed their respective public offering prices. There can be no assurance that the market price of the shares of common stock will ever equal or exceed the exercise price of the pre-funded warrants, and consequently, whether it will ever be profitable for holders of the pre-funded warrants to exercise the pre-funded warrants.

Holders of the pre-funded warrants offered hereby will have no rights as common stockholders with respect to the shares of our common stock underlying the warrants until such holders exercise their warrants and acquire our common stock, except as otherwise provided in the pre-funded warrants.

Until holders of the pre-funded warrants acquire shares of our common stock upon exercise thereof, except as set forth in the pre-funded warrants, such holders will have no rights with respect to the shares of our common stock underlying such warrants. Upon exercise of the pre-funded warrants, the holders will be entitled to exercise the rights of a common stockholder only as to matters for which the record date occurs after the exercise date.

Future sales and issuances of our common stock could result in additional dilution of the percentage ownership of our stockholders and could cause our share price to fall.

We expect that significant additional capital will be needed in the future to continue our planned operations. To the extent we raise additional capital by issuing equity securities, our stockholders may experience substantial dilution. We may sell common stock, convertible securities or other equity securities in one or more transactions at prices and in a manner we determine from time to time. If we sell common stock, convertible securities or other equity securities in more than one transaction, investors may be materially diluted by subsequent sales. Such sales may also result in material dilution to our existing stockholders, and new investors could gain rights superior to our existing stockholders.

We have not paid dividends in the past and have no immediate plans to pay dividends.

We plan to reinvest all of our earnings, to the extent we have earnings, to cover operating costs and otherwise become and remain competitive. We do not plan to pay any cash dividends with respect to our securities in the foreseeable future. We cannot assure you that we would, at any time, generate sufficient surplus cash that would be available for distribution to the holders of our common stock as a dividend. Therefore, you should not expect to receive cash dividends on our common stock.

FORWARD-LOOKING STATEMENTS

This prospectus supplement, the accompanying base prospectus and the reports incorporated by reference herein and therein contain forward-looking statements within the meaning of the federal securities laws, including the Private Securities Litigation Reform Act of 1995. In some cases, you can identify forward-looking statements by the following words: “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “ongoing,” “plan,” “potential,” “predict,” “project,” “should,” or the negative of these terms or other comparable terminology, although not all forward-looking statements contain these words. Forward-looking statements are not a guarantee of future performance or results, and will not necessarily be accurate indications of the times at, or by, which such performance or results will be achieved. Forward-looking statements are based on information available at the time the statements are made and involve known and unknown risks, uncertainties and other factors that may cause our results, levels of activity, performance or achievements to be materially different from the information expressed or implied by the forward-looking statements in this prospectus supplement and the accompanying prospectus. These factors include, but are not limited to, the risk factors included under or incorporated by reference in, “Risk Factors” above and under “Risk Factors” in the accompanying prospectus and filings incorporated by reference herein and therein.

You should read this prospectus supplement, the accompanying base prospectus and the reports incorporated by reference herein and therein, completely and with the understanding that our actual future results may be materially different from any future results expressed or implied by these forward-looking statements.

Forward-looking statements speak only as of the date of this prospectus supplement, the accompanying base prospectus and the reports incorporated by reference herein and therein, as applicable and any free writing prospectus, as applicable. Except to the extent required by applicable law or regulation, we do not undertake any obligation to update forward-looking statements to reflect events or circumstances after the date of this prospectus supplement, any accompanying prospectus or any free writing prospectus or to reflect the occurrence of unanticipated events.

You should also consider carefully the statements under and incorporated by reference in “Risk Factors” in this prospectus supplement, the accompanying base prospectus and the reports incorporated by reference herein and therein and any free writing prospectus, which address additional facts that could cause our actual results to differ from those set forth in the forward-looking statements. We caution investors not to place significant reliance on the forward-looking statements contained in this prospectus supplement, the accompanying base prospectus and the reports incorporated by reference herein and therein and any free writing prospectus. We undertake no obligation to publicly update or review any forward-looking statements, whether as a result of new information, future developments or otherwise, except as otherwise required by law.

You should read this prospectus supplement, the accompanying base prospectus and the reports incorporated by reference herein and therein and any free writing prospectus, and those documents we have filed as exhibits to the registration statement, of which this prospectus is a part, completely and with the understanding that our actual future results may be materially different from what we expect. We qualify all of our forward-looking statements by these cautionary statements.

USE OF PROCEEDS

We estimate that the net combined proceeds from this offering and the concurrent private placement will be approximately $7,289,988, after deducting fees payable to the placement agent and other offering expenses payable by us. This estimate excludes the proceeds, if any, from the exercise of the private placement warrants sold in the concurrent private placement. If all of the private placement warrants sold in the concurrent private placement were exercised for cash, we would receive additional net proceeds of approximately $10,556,759. We cannot predict when or if these private placement warrants will be exercised. It is possible that these private placement warrants may never be exercised.

We expect to use the net proceeds from this offering for working capital and general corporate purposes. This represents our best estimate of the manner in which we will use the net proceeds we receive from this offering based upon the current status of our business, but we have not reserved or allocated amounts for specific purposes and we cannot specify with certainty how or when we will use any of the net proceeds. The amounts and timing of our actual use of the net proceeds from this offering will vary depending on numerous factors, including the factors described under “Risk Factors” located elsewhere in this prospectus supplement, the accompanying base prospectus or in the information incorporated by reference herein or therein. As a result, our management will have broad discretion in the application of the net proceeds, and investors will be relying on our judgment regarding the application of the net proceeds from this offering.

DILUTION

If you invest in our common stock, you will experience immediate dilution to the extent of the difference between the price per share you pay in this offering and the net tangible book value per share of our common stock after this offering.

Our net tangible book value as of September 30, 2025 was approximately ($9,800,000), or approximately ($0.26) per share. Net tangible book value is determined by subtracting our total liabilities from our total tangible assets, and net tangible book value per share is determined by dividing our net tangible book value by the number of outstanding shares of our common stock. After giving further effect to the sale and issuance of 4,063,290 shares of common stock in this offering, at a public offering price of $1.58 per share and 1,000,000 pre-funded warrants at a public offering price of $1.57999 per pre-funded warrant, and deducting placement agent fees and estimated offering expenses payable by us, our pro forma as adjusted net tangible book value as of September 30, 2025, would have been approximately ($2,510,012), or ($0.06) per share of our common stock (assuming the exercise for cash of all pre-funded warrants issued in this offering). This represents an immediate increase in net tangible book value of approximately $0.20 per share to our existing stockholders and an immediate dilution in net tangible book value of approximately $1.64 per share to investors participating in this offering.

The number of shares of common stock to be outstanding is based on 37,765,589 shares of common stock outstanding as of September 30, 2025, and excludes the following:

DESCRIPTION OF SECURITIES WE ARE OFFERING

We are offering 4,063,290 shares of our common stock to investors pursuant to this prospectus supplement and the accompanying base prospectus. We are also offering up to 1,000,000 pre-funded warrants to those purchasers whose purchase of shares of common stock in this offering would result in the purchaser, together with its affiliates and certain related parties, beneficially owning more than 4.99% (or, at the election of the purchaser, 9.99%) of our outstanding shares of common stock following the consummation of this offering in lieu of the shares of common stock that would result in such excess ownership. Each pre-funded warrant will be exercisable for one share of common stock. We are also registering the shares of common stock issuable from time to time upon exercise of the pre-funded warrants offered hereby.

Common Stock

The material terms and provisions of our common stock are described under the caption “Description of Common Stock” in the accompanying base prospectus.

Pre-funded Warrants

The following summary of certain terms and provisions of the pre-funded warrants that are being offered hereby is not complete and is subject to, and qualified in its entirety by, the provisions of the pre-funded warrant, the form of which is filed as an exhibit to the registration statement of which this prospectus forms a part. Prospective investors should carefully review the terms and provisions of the form of pre-funded warrant for a complete description of the terms and conditions of the pre-funded warrants.

Duration and Exercise Price

Each pre-funded warrant offered hereby will have an initial exercise price per warrant share equal to $0.00001. The pre-funded warrants will be immediately exercisable and will expire when exercised in full. The exercise price and number of shares of common stock issuable upon exercise is subject to appropriate adjustment in the event of share dividends, share splits, reorganizations or similar events affecting our shares of common stock.

Exercisability

The pre-funded warrants will be exercisable, at the option of each holder, in whole or in part, by delivering to us a duly executed exercise notice accompanied by payment in full for the number of shares of common stock purchased upon such exercise (except in the case of a cashless exercise as discussed below). A holder (together with its affiliates) may not exercise any portion of the pre-funded warrant to the extent that the holder would own more than 4.99% (or, at the election of the holder, 9.99%) of the outstanding shares of common stock immediately after exercise. However, upon notice from the holder to us, the holder may decrease or increase the holder’s beneficial ownership limitation, which may not exceed 9.99% of the number of outstanding shares of common stock immediately after giving effect to the exercise, as such percentage ownership is determined in accordance with the terms of the pre-funded warrants, provided that any increase in the beneficial ownership limitation will not take effect until 61 days following notice to us.

Cashless Exercise

In lieu of making the cash payment otherwise contemplated to be made to us upon such exercise in payment of the aggregate exercise price, the holder may elect instead to receive upon such exercise (either in whole or in part) the number of shares of common stock determined according to a formula set forth in the pre-funded warrants.

Fractional Shares

No fractional shares of common stock will be issued upon the exercise of the pre-funded warrants. Rather, at our election, the number of shares of common stock to be issued will be rounded up to the nearest whole number or we will pay a cash adjustment in an amount equal to such fraction multiplied by the exercise price.

Transferability

Subject to applicable laws, a pre-funded warrant may be transferred at the option of the holder upon surrender of the pre-funded warrants to us together with the appropriate instruments of transfer.

Trading Market

There is no established trading market for the pre-funded warrants, and we do not expect an active trading market to develop. We do not intend to list the pre-funded warrants on any securities exchange or other trading market. Without a trading market, the liquidity of the pre-funded warrants will be extremely limited. The shares of common stock issuable upon exercise of the pre-funded warrants are currently traded on Nasdaq.

Rights as a Stockholder

Except as otherwise provided in the pre-funded warrants or by virtue of such holder’s ownership of shares of common stock, the holders of the pre-funded warrants do not have the rights or privileges of holders of our shares of common stock, including any voting rights, until such holder exercise their pre-funded warrants. The pre-funded warrants provide that holders have the right to participate in distributions or dividends paid on our shares of common stock.

PRIVATE PLACEMENT TRANSACTION

Concurrently with the sale of securities in this offering, we will issue and sell to the investors in this offering the private placement warrants to purchase up to an aggregate of 7,594,935 shares of common stock at an exercise price equal to $1.39 per warrant share.

The private placement warrants and the shares of common stock issuable upon the exercise of such warrants are not being registered under the Securities Act, are not being offered pursuant to this prospectus supplement and the accompanying base prospectus and are being offered pursuant to the exemption provided in Section 4(a)(2) under the Securities Act and/or Rule 506(b) promulgated thereunder. Accordingly, purchasers may only sell shares of common stock issued upon exercise of the private placement warrants pursuant to an effective registration statement under the Securities Act covering the resale of those shares, an exemption under Rule 144 under the Securities Act or another applicable exemption under the Securities Act.

The following sets forth the material terms of the private placement warrants.

Exercisability

The private placement warrants will be immediately exercisable and will expire five (5) years from the issuance date. Each of the private placement warrants will be exercisable, at the option of each holder, in whole or in part by delivering to us a duly executed exercise notice, accompanied by payment in full in immediately available funds for the number of shares of common stock purchased upon such exercise (except in the case of a cashless exercise as discussed below). If a registration statement registering the issuance of the shares of common stock underlying the private placement warrants under the Securities Act is not effective or available, the holder may, in its sole discretion, beginning 30 days from the issuance date, elect to exercise the private placement warrants through a cashless exercise, in which case the holder would receive upon such exercise the net number of shares of common stock determined according to the formula set forth in the warrant.

No fractional shares of common stock will be issued in connection with the exercise of a private placement warrant. In lieu of fractional shares, we will pay the holder an amount in cash equal to the fractional amount multiplied by the exercise price or round down to the next whole share.

Exercise Limitation

A holder will not have the right to exercise any portion of the private placement warrants if the holder (together with its affiliates) would beneficially own in excess of 4.99% (or, upon election of the holder, 9.99%) of the number of shares of our common stock outstanding immediately after giving effect to the exercise, as such percentage ownership is determined in accordance with the terms of the private placement warrants. However, any holder may increase or decrease such percentage, provided that any increase will not be effective until the 61st day after such election.

Exercise Price Adjustment

The exercise price of the private placement warrants is subject to appropriate adjustment in the event of certain stock dividends and distributions, stock splits, stock combinations, reclassifications or similar events affecting our common stock and also upon any distributions of assets, including cash, stock or other property to our stockholders.

Exchange Listing

There is no established trading market for the private placement warrants and we do not expect a market to develop. In addition, we do not intend to apply for the listing of the private placement warrants on any national securities exchange or other trading market.

Fundamental Transactions

If a fundamental transaction occurs, then the successor entity will succeed to, and be substituted for us, and may exercise every right and power that we may exercise and will assume all of our obligations under the private placement warrants with the same effect as if such successor entity had been named in the warrant itself. If holders of our common stock are given a choice as to the securities, cash or property to be received in a fundamental transaction, then the holder shall be given the same choice as to the consideration it receives upon any exercise of the private placement warrants following such fundamental transaction.

Rights as a Stockholder

Except as otherwise provided in the private placement warrants or by virtue of such holder’s ownership of shares of our common stock, the holder of private placement warrants will not have the rights or privileges of a holder of our common stock, including any voting rights, until the holder exercises the warrant.

Resale/Registration Rights

We are required to file a registration statement on Form S-1 or another appropriate form providing for the resale of the shares of common stock issued and issuable upon the exercise of the private placement warrants (the “Resale Registration Statement”). We are required to use commercially reasonable efforts to file such registration statement within thirty (30) calendar days following the close of this offering and to cause such registration statement to become effective within sixty (60) calendar days following the closing date (or, in the event of a full review by the SEC, ninety (90) calendar days following the filing date). We must also keep such registration statement effective at all times until no investor owns any warrants or shares issuable upon exercise thereof. 

PLAN OF DISTRIBUTION

Aegis Capital Corp., or Aegis, has agreed to act as our sole placement agent in connection with this offering subject to the terms and conditions of a placement agency agreement, dated January 5, 2026, between Aegis and us. Aegis is not purchasing or selling any securities offered by this prospectus supplement, nor is the placement agent required to arrange the purchase or sale of any specific number or dollar amount of the securities offered. The placement agent has agreed to use best efforts to arrange for the sale of all of the securities offered hereby. Therefore, we may not sell the entire amount of the securities offered pursuant to this prospectus supplement. The placement agent may engage one or more sub-agents or selected dealers in connection with this offering.

In connection with the offering, we entered into a securities purchase agreement with each purchaser. This agreement includes representations and warranties by us and each purchaser. The public offering price of the securities in this offering has been determined based upon arm’s-length negotiations between the purchasers and us. Our obligation to issue and sell the securities to the investors is subject to the closing conditions set forth in the securities purchase agreement, including the absence of any material adverse change in our business and the receipt of certain opinions, letters and certificates from us or our counsel, which may be waived by the respective parties. All of the securities will be sold at the offering price specified in this prospectus supplement and, we expect, at a single closing.

The securities being offered pursuant to this prospectus supplement and the accompanying prospectus are being bought by certain accredited investors pursuant to the securities purchase agreement, with Aegis Capital Corp. acting as placement agent in connection with this offering.

Commissions and Expenses

We have agreed to pay the placement agent an aggregate cash placement fee equal to six percent (6.0%) of the gross proceeds in this offering. We have also agreed to reimburse the Placement Agent for reasonable legal fees and disbursements incurred by the placement agent not to exceed an aggregate of $80,000. We estimate that the total expenses payable by us in connection with this offering, other than the placement agent fees referred to above, will be approximately $230,000.

Discretionary Accounts

Aegis has informed us that it does not expect to make sales to accounts over which it exercises discretionary authority in excess of five percent (5%) of the securities being offered in this offering.

Indemnification

We have agreed to indemnify Aegis, its affiliates, and each person controlling Aegis against any losses, claims, damages, judgments, assessments, costs, and other liabilities, as the same are incurred (including the reasonable fees and expenses of counsel), relating to or arising out of the offering, undertaken in good faith.

Lock-Up Agreements

Pursuant to certain “lock-up” agreements, our executive officers, directors, and holders of at least 10% of our Company’s Common Stock and securities exercisable for or convertible into its Common Stock outstanding immediately upon the closing of this offering, have agreed, subject to certain exceptions, not to offer, sell, assign, transfer, pledge, contract to sell, or otherwise dispose of or announce the intention to otherwise dispose of, or enter into any swap, hedge or similar agreement or arrangement that transfers, in whole or in part, the economic risk of ownership of, directly or indirectly, engage in any short selling of any shares of Common Stock or securities convertible into or exchangeable or exercisable for any shares of Common Stock (“Lock-Up Securities”), whether currently owned or subsequently acquired, without the prior written consent of the placement agent, for a period of sixty (60) days after the effective date of the Resale Registration Statement.

The placement agent, in its sole discretion, may release the Common Stock and other securities subject to the lock-up agreements described above in whole or in part at any time. When determining whether or not to release Common Stock and other securities from lock-up agreements, the placement agent will consider, among other factors, the holder’s reasons for requesting the release, the number of shares of Common Stock and other securities for which the release is being requested and market conditions at the time.

Company Standstill

In connection with the Placement, without the prior written consent of the investors, we will not, for a period of forty-five (45) days after the effectiveness of the registration statement (the “Standstill Period”), (a) offer, sell, issue, or otherwise transfer or dispose of, directly or indirectly, any equity of our Company or any securities convertible into or exercisable or exchangeable for equity of our Company; (b) file or cause to be filed any registration statement with the Commission relating to the offering of any equity of our Company or any securities convertible into or exercisable or exchangeable for equity of our Company; or (c) enter into any agreement or announce the intention to effect any of the actions described in subsections (a) or (b) hereof (all of such matters, the “Standstill Restrictions”). So long as none of such equity securities shall be saleable in the public market until the expiration of the Standstill Period, the following matters shall not be prohibited by the Standstill Restrictions: (i) the adoption of an equity incentive plan and the grant of awards or equity pursuant to any equity incentive plan, and the filing of a registration statement on Form S-8; (ii) securities issued pursuant to agreements, options, restricted share units or convertible securities existing as of the date hereof provided the terms are not modified; and (iii) securities issued pursuant to acquisitions or strategic transactions (whether by merger, consolidation, purchase of equity, purchase of assets, reorganization or otherwise) approved by a majority of the disinterested directors of our Company, provided that such securities are issued as “restricted securities” (as defined in Rule 144) and carry no registration rights that require or permit the filing of any registration statement in connection therewith during the Standstill Period, and provided that any such issuance shall only be to a person or entity (or to the equityholders of an entity) which is, itself or through its subsidiaries, an operating company or an owner of an asset in a business synergistic with the business of our Company and shall provide to our Company additional benefits in addition to the investment of funds, but shall not include a transaction in which our Company is issuing securities primarily for the purpose of raising capital or to an entity whose primary business is investing in securities. In no event should any equity transaction during the Standstill Period result in the sale of equity at an offering price to the public less than that of this offering.

Tail Financing

Aegis shall be entitled to compensation with respect to any public or private offering or other financing or capital raising transaction of any kind (“Tail Financing”) to the extent that such financing or capital is provided to us by investors Aegis has introduced to us and/or contacted on our behalf through an in-person, electronic or telephonic communication or investors that Aegis had “wall-crossed” in connection with this offering (or any entity under common management or having a common investment advisor), if such Tail Financing is consummated at any time within the twelve (12) months period beginning on the Closing or the expiration or termination of engagement letter between Aegis and us dated December 9, 2025.

Other Relationships

The placement agent is a full service financial institution engaged in various activities, which may include sales and trading, commercial and investment banking, advisory, investment management, investment research, principal investment, hedging, market making, brokerage and other financial and non-financial activities and services. The placement agent may in the future provide various investment banking, commercial banking and other financial services for us and our affiliates for which they may in the future receive customary fees.

In the ordinary course of its business activities, the placement agent and its affiliates, officers, directors and employees may purchase, sell or hold a broad array of investments and actively traded securities, derivatives, loans, commodities, currencies, credit default swaps and other financial instruments for their own account and for the accounts of their customers, and such investment and trading activities may involve or relate to assets, securities and/or instruments of the issuer (directly, as collateral securing other obligation or otherwise) publish or express independent research views in respect of such assets, securities or instruments and may at any time hold, or recommend to clients that they should acquire, long and/or short positions in such assets, securities and instruments.

Determination of Offering Price

The public offering price of the securities we are offering was negotiated between us and the investors, in consultation with the placement agent based on the trading of our Common Stock prior to the offering, among other things. Other factors considered in determining the public offering price of the securities we are offering include our history and prospects, the stage of development of our business, our business plans for the future and the extent to which they have been implemented, an assessment of our management, general conditions of the securities markets at the time of the offering and such other factors as were deemed relevant.

Regulation M

The placement agent may be deemed to be an underwriter within the meaning of Section 2(a)(11) of the Securities Act, and any commissions received by it and any profit realized on the resale of the securities sold by it while acting as principal might be deemed to be underwriting discounts or commissions under the Securities Act. As an underwriter, the placement agent would be required to comply with the requirements of the Securities Act and the Securities Exchange Act of 1934, as amended (the “Exchange Act”), including, without limitation, Rule 415(a)(4) under the Securities Act and Rule 10b-5 and Regulation M under the Exchange Act. These rules and regulations may limit the timing of purchases and sales of shares of Common Stock by the placement agent acting as principal. Under these rules and regulations, the placement agent:

Indemnification

We have agreed to indemnify the placement agent against certain liabilities, including liabilities under the Securities Act, and liabilities arising from breaches of representations and warranties contained in the placement agency agreement, or to contribute to payments that the placement agent may be required to make in respect of those liabilities.

Potential Conflicts of Interest

The placement agent and its affiliates may, from time to time, engage in transactions with and perform services for us in the ordinary course of their business for which it may receive customary fees and reimbursement of expenses. In the ordinary course of its various business activities, the placement agent and its affiliates may make or hold a broad array of investments and actively trade debt and equity securities (or related derivative securities) and financial instruments (including bank loans) for its own accounts and for the accounts of its customers and such investment and securities activities may involve securities and/or instruments of our Company. The placement agent and its affiliates may also make investment recommendations and/or publish or express independent research views in respect of such securities or instruments and may at any time hold, or recommend to clients that they acquire, long and/or short positions in such securities and instruments.

Electronic Distribution

This prospectus may be made available in electronic format on websites or through other online services maintained by the placement agent or by an affiliate. Other than this prospectus, the information on the placement agent’s website and any information contained in any other website maintained by the placement agent is not part of this prospectus supplement and the accompanying base prospectus or the registration statement of which this prospectus supplement and the accompanying base prospectus forms a part, has not been approved and/or endorsed by us or the placement agent, and should not be relied upon by investors.

Offer Restrictions Outside the United States

Other than in the United States, no action has been taken by us or the placement agent that would permit a public offering of the securities offered by this prospectus in any jurisdiction where action for that purpose is required. The securities offered by this prospectus may not be offered or sold, directly or indirectly, nor may this prospectus or any other offering material or advertisements in connection with the offer and sale of any such securities be distributed or published in any jurisdiction, except under circumstances that will result in compliance with the applicable rules and regulations of that jurisdiction. Persons who come into possession of this prospectus are advised to inform themselves about and to observe any restrictions relating to the offering and the distribution of this prospectus. This prospectus does not constitute an offer to sell or a solicitation of an offer to buy any securities offered by this prospectus in any jurisdiction in which such an offer or a solicitation is unlawful.

Transfer Agent and Registrar

The transfer agent and registrar for our Common Stock is VStock Transfer, LLC.

Trading Market

Our Common Stock Common Stock is listed on the Nasdaq Capital Market under the symbol “ESLA.” We do not intend to apply for listing of the Pre-funded Warrants on any securities exchange or other nationally recognized trading system.

LEGAL MATTERS

The validity of the securities offered by this prospectus supplement will be passed upon for us by Winston & Strawn LLP, Houston, Texas. Sichenzia Ross Ference Carmel LLP, New York, New York is acting as counsel for the placement agent in connection with this offering.

EXPERTS

The consolidated financial statements of Estrella Immunopharma, Inc. as of and for the transition period ended December 31, 2024, and for the fiscal year ended June 30, 2024, have been audited by Macias Gini & O’Connell LLP, an independent registered public accounting firm, as set forth in their report thereon, included in our Transition Report and Annual Report on Form 10-K for the fiscal year ended June 30, 2024, respectively, and incorporated herein by reference. Such consolidated financial statements have been incorporated herein by reference in reliance upon such report given on the authority of such firm as experts in accounting and auditing. The report of Macias Gini & O’Connell LLP contains an explanatory paragraph regarding substantial doubt about our ability to continue as a going concern.

The financial statements of Estrella Biopharma, Inc. (now known as Estrella Immunopharma, Inc.) as of June 30, 2023 and for the year ended June 30, 2023, appearing in the Annual Report on Form 10-K of Estrella Immunopharma, Inc. for the year ended June 30, 2024, have been audited by Marcum LLP, independent registered public accountants, as set forth in their report dated October 5, 2023 (except for the sixth paragraph of Note 3, as to which the date is September 26, 2024), which includes an explanatory paragraph as to the Company’s ability to continue as a going concern. Such financial statements are incorporated herein by reference in reliance upon such report given on the authority of such firm as experts in accounting and auditing. Marcum LLP was dismissed as auditors on January 30, 2024 and, accordingly, has not performed any audit or review procedures with respect to any financial statements appearing in such Prospectus for the periods after the date of their dismissal.

WHERE YOU CAN FIND MORE INFORMATION

We have filed with the SEC a registration statement under the Securities Act (SEC File No. 333-283770) that registers the securities offered hereby. The registration statement, including the exhibits and schedules attached thereto and the information incorporated by reference therein, contains additional relevant information about the securities and our Company, which we are allowed to omit from this prospectus supplement pursuant to the rules and regulations of the SEC. In addition, we file annual, quarterly and current reports and proxy statements and other information with the SEC. Our SEC filings are available on the SEC’s website at www.sec.gov. Copies of certain information filed by us with the SEC are also available free of charge on our website at www.estrellabio.com/investors. We have not incorporated by reference into this prospectus supplement the information on our website and it is not a part of this document.

PROSPECTUS

Estrella Immunopharma, Inc.

$100,000,0000
Common Stock

Warrants

We may offer and sell up to $100,000,000 of the securities described in this prospectus from time to time in one or more transactions. This prospectus describes the general terms of these securities and the general manner in which these securities will be offered. We will provide the specific terms of these securities in supplements to this prospectus. The prospectus supplements will also describe the specific manner in which these securities will be offered and may also supplement, update, or amend information contained in this prospectus. You should read this prospectus and any applicable prospectus supplement, as well as the documents incorporated or deemed to be incorporated by reference herein or therein, before you invest. We may offer these securities in amounts, at prices, and on terms determined at the time of offering.

Our common stock (“Common Stock”) is traded on the Nasdaq Capital Market (“Nasdaq”) under the symbol “ESLA.” On December 3, 2024, the closing price of our Common Stock was $1.27 per share. Each prospectus supplement will indicate whether the securities offered thereby will be listed on any securities exchange.

The address of our principal executive offices is 5858 Horton Street, Suite 370, Emeryville, CA 94608. Our phone number is (510) 318-9098.

The aggregate market value of the outstanding shares of our Common Stock held by non-affiliates is approximately $12,949,121.93, which was calculated in accordance with General Instruction I.B.6 of Form S-3 and is based on 10,196,159 shares outstanding held by non-affiliates as of December 4, 2024, and a price per share of $1.27, which was the last reported sale price of our Common Stock on the Nasdaq Capital Market on December 3, 2024. Pursuant to General Instruction I.B.6 of Form S-3, in no event will the aggregate market value of securities sold by us or on our behalf in a primary offering pursuant to the registration statement of which this prospectus forms a part during any 12-calendar-month period exceed one-third of the aggregate market value of our Common Stock held by non-affiliates, so long as the aggregate market value of our Common Stock held by non-affiliates is less than $75.0 million. During the 12 calendar months prior to and including the date of this prospectus, we have not offered or sold any securities pursuant to General Instruction I.B.6 of Form S-3.

We are an emerging growth company and a smaller reporting company as defined under federal securities laws and, as such, may elect to comply with certain reduced public company reporting requirements for future filings. Investing in our securities involves certain risks. See “Risk Factors” on page 1 of this prospectus, contained in any applicable prospectus supplement, and in the documents incorporated by reference herein and therein for a discussion of the factors you should carefully consider before deciding to purchase our securities.

NEITHER THE SECURITIES AND EXCHANGE COMMISSION NOR ANY STATE SECURITIES COMMISSION HAS APPROVED OR DISAPPROVED OF THESE SECURITIES OR PASSED UPON THE ADEQUACY OR ACCURACY OF THIS PROSPECTUS. ANY REPRESENTATION TO THE CONTRARY IS A CRIMINAL OFFENSE.

The date of this prospectus is December 12, 2024.

TABLE OF CONTENTS

RISK FACTORS

Investing in our securities involves significant risks. Please see the risk factors under the heading “Risk Factors” in any prospectus supplement as well as in our most recent Annual Report on Form 10-K and in our Quarterly Reports on Form 10-Q filed subsequent to the Annual Report on Form 10-K, which are on file with the Securities and Exchange Commission, or the SEC, and are incorporated by reference in this prospectus and any prospectus supplement in their entirety, as the same may be amended, supplemented, or superseded from time to time by our filings under the Securities Exchange Act of 1934, as amended, or the Exchange Act. Before making an investment decision, you should carefully consider these risks as well as other information we include or incorporate by reference in this prospectus and any prospectus supplement. The risks and uncertainties we have described are not the only ones facing our company. These risks, and additional risks not known to us or that we currently believe are immaterial, could materially and adversely affect our business, operating results, cash flows, financial condition, or prospects, and the securities offered by means of this prospectus, and could result in a partial or complete loss of your investment.

CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus contains “forward-looking statements” within the meaning of Section 27A of the Securities Act, and Section 21E of the Exchange Act, with respect to our financial condition, results of operations and business, plans, objectives and strategies. We intend such forward-looking statements to be covered by the safe harbor provisions for forward-looking statements contained in the Private Securities Litigation Reform Act of 1995 and include this statement for purposes of complying with these safe harbor provisions.

This prospectus contains forward-looking statements. All statements other than statements of historical facts contained in this prospectus are forward-looking statements. This includes, without limitation, statements regarding our vision and business strategy, including the plans and objectives of management for our future operations; our market opportunities, our future revenue opportunities, performance of our partnerships, and our future performance and financial condition. Such statements can be identified by the fact that they do not relate strictly to historical or current facts. When used in this prospectus, words such as “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “expected to,” “intend,” “may,” “might,” “plan,” “possible,” “potential,” “predict,” “project,” “should,” “strive,” “would,” and similar expressions may identify forward-looking statements, but the absence of these words does not mean that a statement is not forward-looking. Forward-looking statements are predictions, projections, and other statements about future events that are based on current expectations and assumptions and, as a result, are subject to risks and uncertainties. Many factors could cause actual future events to differ materially from the forward-looking statements in this prospectus, including, but not limited to:

These forward-looking statements are based on information available as of the date of this prospectus and current expectations, forecasts, and assumptions, and involve a number of judgments, risks, and uncertainties. Accordingly, forward-looking statements should not be relied upon as representing our views as of any subsequent date, and we do not undertake any obligation to update forward-looking statements to reflect events or circumstances after the date they were made, whether as a result of new information, future events, or otherwise, except as may be required under applicable securities laws. We intend the forward-looking statements contained in this prospectus to be covered by the safe harbor provisions for forward-looking statements contained in Section 27A of the Securities Act of 1933, as amended, or the “Securities Act”, and Section 21E of the Securities Exchange Act of 1934, as amended, or the “Exchange Act”.

As a result of a number of known and unknown risks and uncertainties, our actual results or performance may be materially different from those expressed or implied by these forward-looking statements. You should not place undue reliance on these forward-looking statements.

ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement on Form S-3 that we filed with the Securities and Exchange Commission, or the “SEC,” using a “shelf” registration process for the delayed offering and sale of securities pursuant to Rule 415 under the Securities Act. Under this shelf process, we may offer and sell any combination of the securities described in this prospectus in one or more offerings up to a total dollar amount of $100,000,000. Specific information about the terms of an offering will be included in a prospectus or a prospectus supplement relating to each offering of securities. That prospectus supplement may include a discussion of any risk factors or other special considerations that apply to those securities. The prospectus supplement may also add, update, or change information included in this prospectus. You should carefully read both this prospectus, any prospectus supplement, any free writing prospectus that we authorize to be distributed to you, and any information incorporated by reference into the foregoing, together with additional information described under the headings “Incorporation of Certain Documents by Reference” and “Where You Can Find More Information” before investing in any of the securities offered under this prospectus.

We have not authorized anyone to give you any additional information different from that contained in this prospectus, any accompanying prospectus supplement or any free writing prospectus provided in connection with an offering. We take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. We are not making an offer to sell these securities in any jurisdiction where the offer is not permitted.

This prospectus contains summaries of certain provisions contained in some of the documents described herein, but reference is made to the actual documents for complete information. All of the summaries are qualified in their entirety by reference to the actual documents.

The information contained in this prospectus is accurate only as of the date on the front cover of this prospectus or prospectus supplement, or that the information contained in any document incorporated by reference into this prospectus or any prospectus supplement, regardless of when this prospectus is delivered or when any sale of our securities occurs. Our business, financial condition, results of operations, cash flows, and prospects may have changed since that date. If there is any inconsistency between the information in this prospectus or any information incorporated by reference herein and in a prospectus supplement, you should rely on the information in that prospectus supplement with the most recent date.

This prospectus is not an offer to sell or solicitation of an offer to buy our securities in any circumstances under which or jurisdiction in which the offer or solicitation is unlawful. Unless the context otherwise indicates, the terms “the Company,” “we,” “our,” “ours,” and “us” refer to Estrella Immunopharma, Inc. The phrase “this prospectus” refers to this prospectus and any applicable prospectus supplement, unless the context otherwise requires. In this prospectus, we sometimes refer to the Common Stock and warrants collectively as the “securities.”

Estrella Immunopharma, Inc.

Estrella Immunopharma, Inc. is a clinical-stage biopharmaceutical company developing T-cell therapies with the capacity to address treatment challenges for patients with cancers and autoimmune diseases. Our mission is to harness the evolutionary power of the human immune system to transform the lives of patients fighting cancer and autoimmune disease with safe, effective therapies. To accomplish this mission, our lead product candidate, EB103, which is a T-cell therapy we also call “CD19-Redirected ARTEMIS^® T-Cell Therapy,” utilizes Eureka Therapeutics, Inc.’s (“Eureka”) ARTEMIS^® technology to target CD19. Unlike a traditional CAR-T cell, the unique design of an ARTEMIS^® T-Cell, like EB103 T-cells, allows it to be activated and regulated upon engagement with cancer targets that use a cellular mechanism more closely resembling the one from the endogenous T-cell receptor (TCR). EB103 is currently undergoing a Phase I/II clinical trial (STARLIGHT-1) to assess safety and determine the Recommended Phase II Dose (RP2D) in patients with relapsed/refractory B-cell Non-Hodgkin’s Lymphomas. As of September 2024, two patients have been treated in the STARLIGHT-1 clinical trial.

We are also developing EB104, a T-cell therapy we also call “CD19/22 Dual-Targeting ARTEMIS^® T-Cell Therapy.” Like EB103, EB104 utilizes Eureka’s ARTEMIS^® technology to target not only CD19, but also CD22, a protein that, like CD19, is expressed on the surface of most B-cell malignancies. EB104’s dual-targeting strategy has the potential to more effectively treat patients with lower surface CD19 density or a greater prevalence of CD22, and reduce relapse due to CD19 antigen loss.

Solid tumors represent approximately 90% of all cancers. To date, T-cell therapy such as CAR-T has demonstrated limited success treating solid tumors. One major barrier limiting the potential of T-cell therapy is the lack of tumor-specific targets. We believe that, in collaboration with Imugene and Imugene’s product candidate, CF33-CD19t, an oncolytic virus, EB103 T-cells have the potential to overcome this barrier using a “mark and kill” strategy. This “mark and kill” strategy entails using CF33-CD19t, to induce solid tumor cells into expressing the CD19 protein on the cell surface. Our EB103 T-cells can then pursue and kill the now CD19-expressing solid tumor cells, offering a potential treatment to cancers that lack solid tumor-specific targets.

Our Common Stock trades on the Nasdaq Capital Market under the stock ticker symbol “ESLA.”

USE OF PROCEEDS

We intend to use the net proceeds from the sale of any securities offered by us under this prospectus for general corporate purposes unless otherwise indicated in the applicable prospectus supplement. General corporate purposes may include, but are not limited to, the acquisition of companies or businesses, repayment and refinancing of debt, investments in existing or future projects, repurchasing or redeeming securities, working capital, and capital expenditures. We may temporarily invest the net proceeds in investment-grade, interest-bearing securities until they are used for their stated purpose. We have not determined the amount of net proceeds to be used specifically for such purposes or the timing of these expenditures, and the net proceeds from the sale of the securities have not been accounted for in our normal budgeting process. The amounts actually expended for these purposes may vary significantly and will depend on a number of factors, including the amount of cash we generate from future operations, the actual expenses of operating our business, and opportunities that may be or become available to us. As a result, management will retain broad discretion over the allocation of net proceeds. Additional information on the use of net proceeds we receive from the sale of securities covered by this prospectus may be set forth in the prospectus supplement relating to the specific offering.

GENERAL DESCRIPTION OF SECURITIES

We may offer under this prospectus:

The following description of the terms of these securities sets forth some of the general terms and provisions of securities that may be offered. The particular terms of securities offered by any prospectus supplement and the extent, if any, to which the general terms set forth below do not apply to those securities, will be described in the related prospectus supplement. Any prospectus supplement may add, change, update, or supersede the information contained in this prospectus. The prospectus supplement will also contain information, where applicable, about material U.S. Federal income tax considerations relating to the offered securities, and the securities exchange, if any, on which the offered securities will be listed. The descriptions herein and in the applicable prospectus supplement do not contain all of the information that you may find useful or that may be important to you. You should refer to the provisions of the actual documents whose terms are summarized herein and in the applicable prospectus supplement, because those documents, and not the summaries, define your rights as holders of the relevant securities. For more information, please review the forms of these documents, which are or will be filed with the SEC and will be available as described under the heading “Where You Can Find More Information,” below. If the information contained in the prospectus supplement differs from the following description, you should rely on the information in the prospectus supplement.

Whenever references are made in this prospectus to information that will be included in a prospectus supplement, to the extent permitted by applicable law, rules, or regulations, we may instead include such information or add, update, or change the information contained in this prospectus by means of a post-effective amendment to the registration statement of which this prospectus is a part, through filings we make with the SEC that are incorporated by reference in this prospectus, or by any other method as may be permitted under applicable law, rules, or regulations.

DESCRIPTION OF COMMON STOCK AND WARRANTS

The following summary sets forth the material terms of our securities. The following summary is not intended to be a complete summary of the rights and preferences of such securities, and is qualified by reference to our second amended and restated certificate of incorporation (“Amended Charter”) and our amended and restated bylaws (“Bylaws”), a copy of each of which is included as exhibits to the registration statement of which this prospectus forms a part. We urge you to read the Amended Charter and our Bylaws in their entirety for a complete description of the rights and preferences of our securities.

Authorized and Outstanding Stock

The Amended Charter authorizes the issuance of 260,000,000 shares, consisting of 250,000,000 shares of Common Stock, and 10,000,000 shares of preferred stock, par value of $0.0001 per share. As of September 20, 2024, there were 36,190,896 shares of Common Stock issued and outstanding. No shares of preferred stock are currently outstanding.

Voting Power

Each holder of the Common Stock is entitled to one vote per share on matters to be voted on by stockholders. The holders of the Common Stock possess all voting power for the election of Estrella’s directors and all other matters requiring stockholder action.

Dividends

Holders of the Common Stock will be entitled to receive dividends when, as, and if declared by the Estrella Board in accordance with applicable law, in its discretion, out of funds legally available therefor. Estrella has not historically paid any cash dividends on its Common Stock to date and does not intend to pay cash dividends in the foreseeable future. Any payment of cash dividends in the future will be dependent upon Estrella’s revenues and earnings, if any, capital requirements, and general financial conditions. In no event will any stock dividends, stock splits, or combinations of shares be declared or made on the Common Stock unless the shares of the Common Stock at the time outstanding are treated equally and identically.

Liquidation, Dissolution, and Winding Up

In the event of a voluntary or involuntary liquidation, dissolution, or winding up of Estrella, the funds and assets of Estrella that may be legally distributed to Estrella’s stockholders shall be distributed among the holders of then outstanding the Common Stock pro rata in accordance with the number of shares of the Common Stock held by each such holder.

Preemptive or Other Rights

There are no sinking fund provisions applicable to the Common Stock.

Certain Anti-Takeover Provisions of Delaware Law; Amended Charter and Bylaws

The Amended Charter and Bylaws contain, and the General Corporate Law of the State of Delaware (“DGCL”) contains provisions, as summarized in the following paragraphs, that are intended to enhance the likelihood of continued stability in the composition of the Estrella Board and its policies and to discourage coercive takeover practices and inadequate takeover bids. These provisions are also designed to reduce Estrella’s vulnerability to hostile takeovers and to discourage certain tactics that may be used in proxy fights. However, such provisions could have the effect of discouraging others from making tender offers for Estrella’s shares and may have the effect of delaying changes in our control or management. As a consequence, these provisions may also inhibit fluctuations in the market price of Estrella’s securities.

Certain Anti-Takeover Provisions of Delaware Law

Estrella is currently subject to the provisions of Section 203 of the DGCL. This statute prevents certain Delaware corporations, under certain circumstances, from engaging in a “business combination” with:

A “business combination” includes a merger or sale of more than 10% of a corporation’s assets. However, the above provisions of Section 203 would not apply if:

These provisions may have the effect of delaying, deferring, or preventing changes in control of Estrella.

Special Meetings

The Amended Charter provides that special meetings of the stockholders may be called only by or at the direction of the Board, the Chairperson of the Board or the Chief Executive Officer. The Bylaws prohibit the conduct of any business at a special meeting other than as specified in the notice for such meeting. These provisions may have the effect of deferring, delaying or discouraging hostile takeovers or changes in control or management of the Company.

Advance Notice of Director Nominations and New Business

The Bylaws state that in order for a stockholder to propose nominations of candidates to be elected as directors or any other proper business to be considered by stockholders at the annual meeting, such stockholder must, among other things, provide notice thereof in writing to the secretary at the principal executive offices of Estrella within the time periods set forth in the Bylaws. Such notice must contain, among other things, certain information about the stockholder giving the notice (and the beneficial owner, if any, on whose behalf the nomination or proposal is made) and certain information about any nominee or other proposed business. Stockholder proposals of business other than director nominations cannot be submitted in connection with special meetings of stockholders.

The Bylaws allow the Board to adopt by resolution such rules, regulations and procedures for the conduct of any meeting of stockholders which may have the effect of precluding the conduct of certain business at a meeting if such rules, regulations and procedures are not followed. These provisions may also defer, delay or discourage a potential acquirer from conducting a solicitation of proxies to elect the acquirer’s own slate of directors or otherwise attempting to influence or obtain control of the Company.

Supermajority Voting for Amendments to Our Governing Documents

The Amended Charter requires the affirmative vote of at least 66⅔% of the voting power of all shares of Common Stock then outstanding. The Amended Charter provides that the Board is expressly authorized to adopt, amend or repeal the Bylaws and that our stockholders may amend certain provision of the Bylaws only with the approval of at least 66⅔% of the voting power of all shares of our Common Stock then outstanding. These provisions make it more difficult for stockholders to change the Amended Charter or Bylaws and may, therefore, defer, delay or discourage a potential acquirer from conducting a solicitation of proxies to amend the Amended Charter or Bylaws or otherwise attempting to influence or obtain control of the Company.

No Cumulative Voting

The DGCL provides that a stockholder’s right to vote cumulatively in the election of directors does not exist unless the certificate of incorporation specifically provides otherwise. The Amended Charter does not provide for cumulative voting. The prohibition on cumulative voting has the effect of making it more difficult for stockholders to change the composition of the Board.

Classified Board of Directors

The Amended Charter provides that the Board is divided into three classes of directors, with the classes to be as nearly equal in number as possible, designated Class I, Class II and Class III. The terms of Class I, Class II and Class III directors end at our 2024, 2025 and 2026 annual meetings of stockholders, respectively. Directors of each class the term of which shall then expire shall be elected to hold office for a three-year term. The classification of directors has the effect of making it more difficult for stockholders to change the composition of our Board and require a longer time period to do so. The Amended Charter provides that the number of directors will be fixed from time to time exclusively pursuant to a resolution adopted by the Board. The classification of directors has the effect of making it more difficult for stockholders to change the composition of our Board. As a result, in most circumstances, a person can gain control of the Board only by successfully engaging in a proxy contest at two or more meetings of stockholders at which directors are elected.

Removal of Directors; Vacancies

The Amended Charter and Bylaws provide that, so long as the Board is classified, directors may be removed only for cause and only upon the affirmative vote of holders of at least 66 and 2/3% of the voting power of all the then outstanding shares of stock entitled to vote generally in the election of directors, voting together as a single class. Therefore, because stockholders cannot call a special meeting of stockholders, as discussed above, stockholders may only submit a stockholder proposal for the purpose of removing a director at an annual meeting. The Amended Charter and Bylaws provide that vacancies and newly created directorships resulting from any increase in the authorized number of directors shall be filled only by a majority of the directors then in office or by a sole remaining director. Therefore, while stockholders may remove a director, stockholders are not able to elect new directors to fill any resulting vacancies that may be created as a result of such removal.

Stockholder Action by Written Consent

The DGCL permits any action required to be taken at any annual or special meeting of the stockholders to be taken without a meeting, without prior notice and without a vote if a consent in writing, setting forth the action so taken, is signed by the holders of outstanding stock having not less than the minimum number of votes that would be necessary to authorize or take such action at a meeting at which all shares of stock entitled to vote thereon were present and voted, unless the certificate of incorporation provides otherwise. The Amended Charter and Bylaws preclude stockholder action by written consent. This prohibition, combined with the fact stockholders cannot call a special meeting, as discussed above, means that stockholders are limited in the manner in which they can bring proposals and nominations for stockholder consideration, making it more difficult to effect change in our governing documents and the Board.

Warrants

As of the date of this prospectus, 2,214,993 Public Warrants (which means the warrants sold in TradeUP Acquisition Corp.’s IPO as part of the units, whether they were purchased in the IPO or thereafter in the open market) are outstanding. Each whole Public Warrant entitles the registered holder to purchase one share of Common Stock at a price of $11.50 per share, subject to adjustment as discussed below, at any time commencing on the completion of the business combination. However, no Public Warrants will be exercisable for cash unless we have an effective and current registration statement (including a current prospectus) covering the shares of Common Stock issuable upon exercise of the Public Warrants. Notwithstanding the foregoing, during any period when we shall have failed to maintain an effective registration statement, warrant holders may exercise, subject to the terms of the Warrant Agreement, Public Warrants on a cashless basis pursuant to an available exemption from registration under the Securities Act. The Public Warrants will expire on the fifth anniversary of our completion of the business combination, at 5:00 p.m., New York City time, or earlier upon redemption or liquidation.

Redemption

We may call the outstanding Public Warrants for redemption, in whole and not in part, at a price of $0.01 per warrant:

The right to exercise will be forfeited unless the warrants are exercised prior to the date specified in the notice of redemption (the “Redemption Date”). On and after the Redemption Date, a record holder of a Public Warrant will have no further rights except to receive the redemption price for such holder’s Public Warrant upon surrender of such Public Warrant.

The redemption criteria for our Public Warrants have been established at a price which is intended to provide warrant holders a reasonable premium to the initial exercise price and provide a sufficient differential between the then-prevailing share price and the warrant exercise price so that if the share price declines as a result of our redemption call, the redemption will not cause the share price to drop below the exercise price of the Public Warrants. Redemption may occur at a time when the redeemable warrants are “out-of-the-money,” in which case you would lose any potential embedded value from a subsequent increase in the value of our Common Stock had your Public Warrants remained outstanding. Historical trading prices for our Common Stock have not exceeded the $16.50 per share threshold at which the Public Warrants would become redeemable. However, this could occur in the future.

In the event we elect to redeem our Public Warrants, we will notify holders of Public Warrants of such redemption as described in the Warrant Agreement, and we will fix the Redemption Date. Notice of redemption will be mailed by first class mail, postage prepaid, by us not less than 30 days prior to the Redemption Date to the registered holders of the Public Warrants to be redeemed at their last addresses as they appear on the books maintained by the warrant agent, VStock Transfer, LLC. Any notice mailed in the manner provided in the Warrant Agreement will be conclusively presumed to have been duly given whether or not the registered holder received such notice. In addition, beneficial owners of the Public Warrants will be notified of such redemption via posting of the redemption notice to DTC.

If we call the Public Warrants for redemption as described above, our management will have the option to require all holders that wish to exercise warrants to do so on a “cashless basis.” In such event, each holder would pay the exercise price by surrendering the Public Warrants for that number of shares of Common Stock equal to the quotient obtained by dividing (x) the product of the number of shares of Common Stock underlying the Public Warrants, multiplied by the difference between the exercise price of the Public Warrants and the “fair market value” by (y) the fair market value. The “fair market value” shall mean the average reported last sale price of our Common Stock for the 10 trading days ending on the third trading day prior to the date on which the notice of redemption is sent to the holders of Public Warrants. If our management takes advantage of this option, the notice of redemption will contain the information necessary to calculate the number of shares of Common Stock to be received upon exercise of the warrants, including the “fair market value” in such case. Requiring a cashless exercise in this manner will reduce the number of shares of Common Stock to be issued and thereby lessen the dilutive effect of a warrant redemption.

Whether we will exercise our option to require all holders to exercise their Public Warrants on a “cashless basis” will depend on a variety of factors including the price of our common shares at the time the Public Warrants are called for redemption, our cash needs at such time and concerns regarding dilutive share issuances. We believe this feature is an attractive option to us if we do not need the cash from the exercise of the Public Warrants.

The Public Warrants were issued in registered form under the Warrant Agreement which provides that the terms of the Public Warrants may be amended without the consent of any holder to, among other things, cure any ambiguity or correct any defective provision that is not inconsistent with the Warrant Agreement, but requires the approval, by written consent or vote, of the holders of a majority of the then outstanding warrants in order to make any change not permitted by Section 9.8 of the Warrant Agreement, including any amendment to increase the exercise price of the Warrants or shorten the exercise period.

The exercise price and number of shares of Common Stock issuable on exercise of the Warrants may be adjusted in certain circumstances including in the event of a share dividend, extraordinary dividend or our recapitalization, reorganization, merger or consolidation.

The Warrants may be exercised upon surrender of the warrant certificate on or prior to the expiration date at the offices of the warrant agent, with the exercise form on the reverse side of the warrant certificate completed and executed as indicated, accompanied by full payment of the exercise price, by certified or official bank check payable to us, for the number of warrants being exercised. The warrant holders (who are not stockholders of the Company) do not and will not have the rights or privileges of holders of shares of Common Stock, including, without limitation, any voting rights, unless and until they exercise their warrants and receive shares of Common Stock. After the issuance of shares of Common Stock upon exercise of the Warrants, each holder will be entitled to one vote for each share held on all matters to be voted on by stockholders.

Except as described above, no Public Warrants will be exercisable for cash, and we will not be obligated to issue shares of Common Stock unless, at the time a holder seeks to exercise such warrant, a prospectus relating to the shares of Common Stock issuable upon exercise of the Warrants is current and the shares of Common Stock have been registered or qualified or deemed to be exempt under the securities laws of the state of residence of the holder of the Warrants. Under the terms of the Warrant Agreement, we have agreed to use our best efforts to meet these conditions and to maintain a current prospectus relating to the shares of Common Stock issuable upon exercise of the Warrants until the expiration of the Warrants. However, we cannot assure you that we will be able to do so and, if we do not maintain a current prospectus relating to the shares of Common Stock issuable upon exercise of the Warrants, holders will be unable to exercise their Warrants, and we will not be required to settle any such warrant exercise. If the prospectus relating to the shares of Common Stock issuable upon the exercise of the warrants is not current or if the Common Stock is not qualified or exempt from qualification in the jurisdictions in which the holders of the Warrants reside, we will not be required to net cash settle or cash settle the warrant exercise, the Warrants may have no value, the market for the Warrants may be limited, and the Warrants may expire worthless.

A holder of a Warrant may notify us in writing in the event it elects to be subject to a requirement that such holder will not have the right to exercise such Warrant, to the extent that after giving effect to such exercise, such person (together with such person’s affiliates), to the warrant agent’s actual knowledge, would beneficially own in excess of 9.8% (or such other amount as a holder may specify) of Common Stock outstanding.

No fractional shares will be issued upon exercise of the Warrants. If, upon exercise of the Warrants, a holder would be entitled to receive a fractional interest in a share, we will, upon exercise, round down to the nearest whole number the number of shares of Common Stock to be issued to the warrant holder.

We have agreed that, subject to applicable law, any action, proceeding or claim against us arising out of or relating in any way to the Warrant Agreement will be brought and enforced in the courts of the State of New York or the United States District Court for the Southern District of New York, and we irrevocably submit to such jurisdiction, which jurisdiction will be the exclusive forum for any such action, proceeding or claim. This provision applies to claims under the Securities Act but does not apply to claims under the Exchange Act or any claim for which the federal district courts of the United States of America are the sole and exclusive forum.

Our Transfer Agent and Warrant Agent

The transfer agent for our Common Stock and warrant agent for our warrants is VStock Transfer, LLC, 18 Lafayette Place, Woodmere, New York 11598.

Listing of Securities

Our Common Stock and Public Warrants are listed on the Nasdaq Capital Market under the symbols “ESLA” and “ESLAW,” respectively.

DESCRIPTION OF WARRANTS

Set forth below is a description of the general terms and conditions of the warrants that may be offered under this prospectus. The specific terms and conditions of the warrants will be described in a supplement to this prospectus. Any prospectus supplement may add, change, update, or supersede the terms and conditions of the warrants as described in this prospectus. To the extent the information contained in the applicable prospectus supplement differs from the description set forth below, you should rely on the information in the applicable prospectus supplement, warrant agreement, and warrant certificate.

General

We may issue warrants to purchase shares of our Common Stock in one or more series together with other securities or separately, as described in each applicable prospectus supplement. Below is a description of certain general terms and provisions of the warrants that we may offer. Particular terms of the warrants will be described in the applicable warrant agreements and the applicable prospectus supplement for the warrants.

Terms of Warrants

The applicable prospectus supplement will contain, where applicable, the following terms of and other information relating to the warrants:

Exercise of Warrants

Each warrant will entitle the holder of the warrant to purchase at the exercise price set forth in the applicable prospectus supplement the number of shares of Common Stock being offered. Holders may exercise warrants at any time up to the close of business on the expiration date set forth in the applicable prospectus supplement. After the close of business on the expiration date, unexercised warrants will be void. Holders may exercise warrants as described in the prospectus supplement relating to the warrants being offered.

Until a holder exercises the warrants to purchase shares of our Common Stock, the holder will not have any rights as a holder of shares of our Common Stock, as the case may be, by virtue of ownership of the warrants.

Transfer Agent and Registrar

The transfer agent and registrar for any warrants will be set forth in the applicable prospectus supplement.

PLAN OF DISTRIBUTION

We may sell the securities offered through this prospectus or any applicable prospectus supplement in any one or more of the following ways:

We reserve the right to sell securities directly to investors on our own behalf in those jurisdictions where we are authorized to do so.

The securities may be distributed at a fixed price or prices, which may be changed, market prices prevailing at the time of sale, prices related to the prevailing market prices, or negotiated prices. Any of the prices may represent a discount from the prevailing market prices. In the sale of the securities, underwriters, dealers, or agents may receive compensation from us or from purchasers of the securities, for whom they may act as agents, in the form of discounts, concessions, or commissions. Underwriters may sell the securities to or through dealers, and such dealers may receive compensation in the form of discounts, concessions, or commissions from the underwriters and/or commissions from the purchasers for whom they may act as agents. Underwriters, dealers, and agents that participate in the distribution of the securities may be deemed to be underwriters under the Securities Act and any discounts or commissions they receive from us and any profit on the resale of securities they realize may be deemed to be underwriting discounts and commissions under the Securities Act. The prospectus supplement will, where applicable, describe, disclose, or identify:

Any underwritten offering may be on a best efforts or a firm commitment basis. If underwriters are used in the sale, the underwriters will acquire the securities for their own account, including through underwriting, purchase, security lending or repurchase agreements with us. The underwriters may resell the securities from time to time in one or more transactions, including negotiated transactions. Underwriters may sell the securities in order to facilitate transactions in any of our other securities (described in this prospectus or otherwise), including other public or private transactions and short sales. Underwriters may offer securities to the public either through underwriting syndicates represented by one or more managing underwriters or directly by one or more firms acting as underwriters. Unless otherwise indicated in the prospectus supplement, the obligations of the underwriters to purchase the securities will be subject to certain conditions, and the underwriters will be obligated to purchase all the offered securities if they purchase any of them. The underwriters may change from time to time any initial public offering price and any discounts or concessions allowed or re-allowed or paid to dealers.

If dealers are used in the sale of securities offered through this prospectus, we will sell the securities to them as principals. They may then resell those securities to the public at varying prices determined by the dealers at the time of resale. The prospectus supplement will include the names of the dealers and the terms of the transaction.

We may sell the securities offered through this prospectus directly or through agents designated from time to time. The prospectus supplement will name any agent involved in the offer or sale of the offered securities and will describe any commissions payable to the agent. Unless otherwise indicated in the prospectus supplement, any agent will agree to use its reasonable best efforts to solicit purchases for the period of its appointment.

We may sell the securities directly to institutional investors or others who may be deemed to be underwriters within the meaning of the Securities Act with respect to any sale of those securities. The terms of any such sales will be described in the prospectus supplement.

We may also make direct sales through subscription rights distributed to our stockholders on a pro rata basis, which may or may not be transferable. In any distribution of subscription rights to stockholders, if all of the underlying securities are not subscribed for, we may then sell the unsubscribed securities directly to third parties or may engage the services of one or more underwriters, dealers or agents, including standby underwriters, to sell the unsubscribed securities to third parties.

If indicated in the applicable prospectus supplement, securities may also be offered or sold by a “remarketing firm” in connection with a remarketing arrangement contemplated by the terms of the securities. Remarketing firms may act as principals for their own accounts or as agents. The applicable prospectus supplement will identify any remarketing firm and the terms of its agreement, if any, with us. It will also describe the remarketing firm’s compensation. Remarketing firms may be deemed to be underwriters in connection with the remarketing of the securities.

If the prospectus supplement indicates, we may authorize agents, underwriters or dealers to solicit offers from certain types of institutions to purchase securities at the public offering price under delayed delivery contracts. These contracts would provide for payment and delivery on a specified date in the future. The contracts would be subject only to those conditions described in the prospectus supplement. The applicable prospectus supplement will describe the commission payable for solicitation of those contracts.

We may from time to time engage a firm or firms to act as our agent for one or more offerings of our securities. We sometimes refer to any such agent as our “offering agent.” If we reach agreement with an offering agent with respect to a specific offering, including the number of securities and any minimum price below which sales may not be made, then the offering agent will try to sell such securities on the agreed terms. The offering agent could make sales in privately negotiated transactions or any other method permitted by law, including sales deemed to be an “at the market” offering as defined in Rule 415 promulgated under the Securities Act, including sales made directly on an exchange, or sales made to or through a market maker other than on an exchange. Any such offering agent will be deemed to be an “underwriter” within the meaning of the Securities Act with respect to any sales effected through an “at the market” offering.

Unless the applicable prospectus supplement states otherwise, each series of offered securities will be a new issue and will have no established trading market, other than shares of our Common Stock, which are listed on the Nasdaq Capital Market. We may elect to list any series of offered securities on an exchange. Any underwriters that we use in the sale of offered securities may make a market in such securities, but may discontinue such market making at any time without notice. Therefore, we cannot assure you that the securities will have a liquid trading market.

Any underwriter may also engage in stabilizing transactions, syndicate covering transactions and penalty bids in accordance with Rule 104 under the Exchange Act. Stabilizing transactions involve bids to purchase the underlying security in the open market for the purpose of pegging, fixing or maintaining the price of the securities. Syndicate covering transactions involve purchases of the securities in the open market after the distribution has been completed in order to cover syndicate short positions.

Penalty bids permit the underwriters to reclaim a selling concession from a syndicate member when the securities originally sold by the syndicate member are purchased in a syndicate covering transaction to cover syndicate short positions. Stabilizing transactions, syndicate covering transactions and penalty bids may cause the price of the securities to be higher than it would be in the absence of the transactions. The underwriters may, if they commence these transactions, discontinue them at any time.

We, the underwriters, dealers, or other agents may engage in derivative transactions involving the securities. These derivatives may consist of short sale transactions and other hedging activities. The underwriters, dealers, or agents may acquire a long or short position in the securities, hold or resell securities acquired and purchase options or futures on the securities and other derivative instruments with returns linked to or related to changes in the price of the securities. In order to facilitate these derivative transactions, we may enter into security lending or repurchase agreements with the underwriters, dealers, or agents. The underwriters, dealers, or agents may effect the derivative transactions through sales of the securities to the public, including short sales, or by lending the securities in order to facilitate short sale transactions by others. The underwriters, dealers, or agents may also use the securities purchased or borrowed from us or others (or, in the case of derivatives, securities received from us in settlement of those derivatives) to directly or indirectly settle sales of the securities or close out any related open borrowings of the securities.

We may also make sales through the Internet or through other electronic means. Since we may from time to time elect to offer securities directly to the public, with or without the involvement of agents, underwriters, or dealers, utilizing the Internet or other forms of electronic bidding or ordering systems for the pricing and allocation of such securities, you will want to pay particular attention to the description of that system we will provide in a prospectus supplement.

Such electronic system may allow bidders to directly participate, through electronic access to an auction site, by submitting conditional offers to buy that are subject to acceptance by us, and which may directly affect the price or other terms and conditions at which such securities are sold. These bidding or ordering systems may present to each bidder, on a so-called “real-time” basis, relevant information to assist in making a bid, such as the clearing spread at which the offering would be sold, based on the bids submitted, and whether a bidder’s individual bids would be accepted, prorated or rejected.

Upon completion of such an electronic auction process, securities will be allocated based on prices bid, terms of bid or other factors. The final offering price at which securities would be sold and the allocation of securities among bidders would be based in whole or in part on the results of the Internet or other electronic bidding process or auction.

Agents, underwriters, and dealers may be entitled, under agreements entered into with us, to indemnification by us against certain liabilities, including liabilities under the Securities Act. Our agents, underwriters, and dealers, or their affiliates, may be customers of, engage in transactions with or perform services for us, in the ordinary course of business.

To comply with applicable state securities laws, the securities offered by this prospectus will be sold, if necessary, in such jurisdictions only through registered or licensed brokers or dealers. In addition, securities may not be sold in some states unless they have been registered or qualified for sale in the applicable state or an exemption from the registration or qualification requirement is available and is complied with.

WHERE YOU CAN FIND MORE INFORMATION

We are currently subject to the information requirements of the Exchange Act and in accordance therewith file periodic reports, proxy and information statements, and other information with the SEC. This prospectus, which constitutes a part of the registration statement, does not contain all of the information set forth in the registration statement, some of which is contained in exhibits to the registration statement as permitted by the rules and regulations of the SEC. For further information with respect to us and our Common Stock, we refer you to the SEC’s website at www.sec.gov and our website at www.estrellabio.com. Information on our website is not incorporated into this prospectus or our other securities filings and is not a part of this prospectus or any prospectus supplement.

Statements contained in this prospectus concerning the contents of any contract or any other document is not necessarily complete. If a contract or document has been filed as an exhibit to the registration statement, please see the copy of the contract or document that has been filed. Each statement is this prospectus relating to a contract or document filed as an exhibit is qualified in all respects by the filed exhibit.

If you make a request for such information in writing or by telephone, we will provide you, without charge, a copy of any or all of the information incorporated by reference into this prospectus. Any such request should be directed to:

Estrella Immunopharma, Inc.

5858 Horton Street, Suite 370

Emeryville, California 94608

[email protected]

(510) 318-9098

INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE

The SEC allows us to “incorporate by reference” certain information into this prospectus, which means that we can disclose important information about us by referring you to another document filed separately with the SEC. The information incorporated by reference is considered to be a part of this prospectus. Because we are incorporating by reference future filings with the SEC, this prospectus is continually updated and those future filings may modify or supersede some of the information included or incorporated in this prospectus. This means that you must carefully review all of the SEC filings that we incorporate by reference to determine if any of the statements in this prospectus or in any document previously incorporated by reference have been modified or superseded. However, we undertake no obligation to update or revise any statements we make, except as required by law.

This prospectus incorporates by reference the documents listed below (in each case, other than those documents or the portions of those documents not deemed to be filed, including information furnished under Item 2.02 or Item 7.01 of Form 8-K and any corresponding information furnished with respect to such Items under Item 9.01 or as an exhibit):

We also incorporate by reference into this prospectus all reports and documents that we may file with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act after the date of the initial registration statement and prior to effectiveness of the registration statement and after the date of this prospectus but prior to the termination of the offering of the securities hereunder, but excluding any information deemed furnished and not filed with the SEC.

LEGAL MATTERS

The validity of the securities offered by this prospectus has been passed upon for us by Winston & Strawn LLP. Certain legal matters in connection with the securities offered hereby may be passed upon for any underwriters, dealers or agents by counsel that will be named in the applicable prospectus supplement.

EXPERTS

The consolidated financial statements of Estrella Immunopharma, Inc. as of June 30, 2024 and for the year then ended incorporated by reference in this prospectus have been so included in reliance on the report of Macias Gini & O’Connell LLP, an independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting. The report on the consolidated financial statements contains an explanatory paragraph regarding the Company’s ability to continue as a going concern.

The financial statements of Estrella Biopharma, Inc. (now known as Estrella Immunopharma, Inc.) as of June 30, 2023 and for the year then ended incorporated by reference in this prospectus have been so included in reliance on the report of Marcum LLP, an independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting. The report on the financial statements contains an explanatory paragraph regarding the Company’s ability to continue as a going concern.

ESTRELLA IMMUNOPHARMA, INC.

4,063,290 Shares of Common Stock
1,000,000 Pre-Funded Warrants to Purchase Shares of Common Stock
1,000,000 Shares of Common Stock Underlying Pre-Funded Warrants

PROSPECTUS SUPPLEMENT

Aegis Capital Corp.

January 6, 2026.