Imago BioSciences Presents Data From Ongoing Phase 2 Study Of Bomedemstat In Advanced Myelofibrosis At ASH 2022

Imago BioSciences, Inc. (“Imago”) (NASDAQ:IMGO), a clinical-stage biopharmaceutical company discovering and developing new medicines for the treatment of myeloproliferative neoplasms (MPNs) and other bone marrow diseases, today presented positive data from its ongoing global Phase 2 clinical study evaluating bomedemstat in patients with advanced myelofibrosis (MF).

The data were presented in a poster presentation session during the 64th American Society of Hematology Annual Meeting and Exposition (ASH) taking place 10-13 December 2022. A Phase 2 data set with a cut-off date of 29 April 2022 was previously presented at the 30th European Hematology Association Annual Meeting and congress (EHA) in June 2022.

Updated Highlights (available data as of 18 October 2022)

• Of evaluable patients at 24 weeks:
  • 65% (17/26) showed a decrease in Total Symptom Score (TSS).
  • 19% (5/26) showed a ≥ 50% decrease in TSS.
  • 66% (33/50) showed spleen volume reductions from baseline.
  • 28% (14/50) showed a ≥ 20% spleen volume reduction.
• The majority of patients had a decrease in mutant allele frequencies (MAF) including driver mutations (e.g., JAK2) and high molecular risk (HMR) mutations (e.g., ASXL1).
• 90% (37/41) of transfusion-independent patients had stable (19/41) or improved (18/41) hemoglobin at Week 12.
• 85% (50/59) of patients had an improved (19/59) or stable (31/59) bone marrow fibrosis score post-baseline.
• No new mutations or transformations to acute myeloid leukemia (AML) while on treatment, even in patients with a high-risk of progression.

“Bomedemstat continues to demonstrate its potential as a monotherapy for patients suffering from advanced myelofibrosis, highlighted by the data presented at ASH showing improvements in patient symptom scores, spleen volumes, fibrosis, and anemia,” said Hugh Young Rienhoff, Jr., M.D., Chief Executive Officer of Imago BioSciences. “I am also delighted we continue to see the majority of patients experience a decrease in mutant allele frequencies and no progression to AML, even in patients with ASXL1 mutations known to confer a high-risk of transformation. We are further exploring the use of bomedemstat in myelofibrosis in an investigator-sponsored Phase 2 combination study with ruxolitinib; patients are currently being screened.”

Safety and Tolerability

• Bomedemstat was generally safe and well-tolerated in patients with myelofibrosis.
• The most common non-hematologic adverse event (AE) related to bomedemstat was dysgeusia (altered taste), which occurred in 33% (30/90) of patients and led to discontinuation of the study in 1 patient.
• There were 44 patients who reported a total of 86 serious adverse events (SAEs), 16% of which were deemed drug-related by the investigator.

Details on the Imago ASH Poster Presentation

Poster Presentation Title: “A Phase 2 Study of the LSD1 Inhibitor Bomedemstat (IMG-7289) for the Treatment of Advanced Myelofibrosis (MF): Updated Results and Genomic Analyses”
Session Name: Myeloproliferative Syndromes: Clinical and Epidemiological: Poster III
Presentation Date/Time: Monday, December 12, 2022, at 7:00 PM ET
Location: Ernest N. Morial Convention Center, Hall D
Presenting Author: Kristen Pettit, University of Michigan

For further details, please see the ASH 2022 abstract and presentation on the Imago website here.