The results from Phase 1 of the Troculeucel Clinical Trial demonstrated stable/improved outcomes in 90% of subjects, with no drug-related adverse events following troculeucel therapy.

Troculeucel therapy was well-tolerated and resulted in beneficial effects on protein aggregate levels and neuroinflammatory biomarkers in the cerebrospinal fluid, with decreases in pTau181 and GFAP appearing to be dose dependent.

A larger trial with a higher dosing/duration has been initiated in the U.S. and is on-going.

SANTA ANA, Calif., Feb. 13, 2025 (GLOBE NEWSWIRE) -- NKGen Biotech, Inc. (NASDAQ:NKGN) ("NKGen" or the "Company"), a clinical-stage biotechnology company focused on the development and commercialization of innovative autologous and allogeneic natural killer ("NK") cell therapeutics, today announced the publication of results from the Company's initial dose escalation Phase 1 clinical trial of troculeucel, an expanded autologous NK cell therapy, for the treatment of Alzheimer's disease ("AD") in the journal Alzheimer's Research & Therapy, an international peer-reviewed journal with a translational research focus in AD and other neurodegenerative diseases.

The publication showcases important context and further validation of the findings from the Company's Phase 1 clinical study, which evaluated its expanded autologous NK cell therapy, troculeucel, in subjects with either mild, moderate, or severe AD (median CDR-SB 10.0). The clinical trial information in this publication includes comprehensive details on troculeucel preparation, preclinical studies elucidating the mechanism of action, clinical trial design, and trial results (safety assessment, efficacy assessment, and biomarkers). Final Results of the Phase 1 trial were previously disclosed at the Alzheimer's Association International Conference (AAIC 2024).

"We are excited to have our Phase 1 clinical trial published in Alzheimer's Research & Therapy," said Paul Y. Song, MD, Chairman and Chief Executive Officer of NKGen. "Previously presenting our positive findings at major medical conferences has been a great way to share our progress with the medical community, but having these data published in such a respected, peer-reviewed journal certainly elevates the credibility of our work and the importance of having a therapy such as troculeucel. The rigorous peer-review process gives our research further validation, as it has been thoroughly evaluated by experts in the field, which not only strengthens the foundation of our early research but also highlights our potential to shape the future of AD treatment. Additionally, this is an important step towards advancing the scientific understanding of troculeucel as a potential treatment option for AD and other neurodegenerative diseases."

Publication Highlights:

11 subjects (5 males and 6 females) enrolled.
- 10 subjects were evaluable.
- Median age was 79 years (56 to 85 years).
Using a 3 + 3 design to identify the maximum tolerated dose ("MTD") and/or the recommended phase 2 dose ("RP2D"), three dose cohorts (1 × 10⁹ cells, 2 × 10⁹ cells, and 4 × 10⁹ cells) were enrolled, each receiving a total of four doses at three-week intervals.
Despite 70% of subjects being treated at relatively low doses of troculeucel, 90% of all evaluable subjects had either stable or improved (±0.1) composite ADCOMS scores at week 11 (one-week after the final dose), as previously disclosed.
The study demonstrated that adoptive NK cell therapy was well-tolerated.
Treatment with troculeucel reduced neuroinflammation and had a positive effect on brain protein aggregates (as suggested by CSF biomarker levels), which appeared to translate into a stabilization or even an improvement in cognitive function.
Given the role of the innate immune system in AD pathology, a reduction in neuroinflammation as a therapeutic strategy may complement the current available anti-Aβ antibodies.
Since AD is a complex disease, it stands to reason that a multi-pronged approach to treatment, which includes NK cell adoptive therapy, and potentially other anti-inflammatory therapeutic agents, may be able to stabilize or even improve this disease beyond the effect on slowing progression seen with the anti-Aβ antibodies.
The additional ability of NK cell therapy to potentially cause degradation of protein aggregates suggests that this treatment on its own may have therapeutic and/or disease-modifying benefits.

The full publication entitled "Treatment of Alzheimer's Disease subjects with expanded non-genetically modified autologous natural killer cells (SNK01): a phase I study" is available at the following link:

https://alzres.biomedcentral.com/articles/10.1186/s13195-025-01681-2

NKGen's follow-up Phase 1/2a trial on troculeucel in moderate AD is currently enrolling patients for the Phase 2 cohort. For more information, please visit the ClinicalTrials.gov website at https://clinicaltrials.gov/study/NCT06189963.

About Troculeucel

Troculeucel is a novel cell-based, patient specific, ex vivo expanded autologous NK cell immunotherapeutic drug candidate. NKGen is developing troculeucel for the treatment of neurodegenerative disorders and a broad range of cancers. Troculeucel is the International Nonproprietary Name ("INN") for SNK01 assigned by the World Health Organization ("WHO"). The WHO INN approval of troculeucel establishes a universally recognized nonproprietary drug name for SNK01 and marks a significant step on NKGen's journey toward bringing this therapy to market.

About NKGen Biotech

NKGen is a clinical-stage biotechnology company focused on the development and commercialization of innovative autologous and allogeneic NK cell therapeutics. NKGen is headquartered in Santa Ana, California, USA. For more information, please visit www.nkgenbiotech.com.

Forward-Looking Statements

Statements contained in this press release may contain "forward-looking statements" within the meaning of Section 27A of the Securities Act and Section 21E of the Securities Exchange Act of 1934, as amended. Forward-looking statements may be identified by the use of words such as "anticipate", "believe", "could", "continue", "expect", "estimate", "may", "plan", "outlook", "future" and "project" and other similar expressions that predict or indicate future events or trends or that are not statements of historical matters. Because such statements are subject to risks and uncertainties, many of which are outside of the Company's control, actual results may differ materially from those expressed or implied by such forward-looking statements. Such statements include, but are not limited to, statements regarding the Company's plans and expected timing for developing troculeucel and SNK02, including the expected timing of completing and announcing further results from its ongoing clinical studies; and the Company's expected timing for developing its product candidates and potential benefits of its product candidates. Risks that contribute to the uncertain nature of the forward-looking statements include: the Company's ability to execute its plans and strategies; risks related to performing clinical studies; the risk that initial and interim results of a clinical study do not necessarily predict final results and that one or more of the clinical outcomes may materially change as patient enrollment continues, following more comprehensive reviews of the data, and as more patient data become available; potential delays in the commencement, enrollment and completion of clinical studies and the reporting of data therefrom; the risk that studies will not be completed as planned; the risk that the abstract will not be published as planned including delays in timing, format, or accessibility; and NKGen's ability to raise additional funding to complete the development of its product candidates. These and other risks and uncertainties are described more fully under the caption "Risk Factors" and elsewhere in the Company's filings and reports, which may be accessed for free by visiting the Securities and Exchange Commission's website at www.sec.gov and on the Company's website under the subheading "Investors—Financial and Filings". Investors should take such risks into account and should not rely on forward-looking statements when making investment decisions. All forward-looking statements contained in this press release speak only as of the date on which they were made. The Company undertakes no obligation to update such statements to reflect events that occur or circumstances that exist after the date on which they were made, except as required by law.

Internal Contact:

Denise Chua, MBA, CLS, MLS (ASCP)

SVP, Corporate Affairs

949-396-6830

dchua@nkgenbiotech.com

External Contacts:

Chris Calabrese

Managing Director

LifeSci Advisors, LLC

ccalabrese@lifesciadvisors.com

Kevin Gardner

Managing Director

LifeSci Advisors, LLC

kgardner@lifesciadvisors.com

NKGen Biotech Announces Publication of Phase 1 Troculeucel Clinical Trial Results for the Treatment of Alzheimer's Disease