Moleculin Reports 43% And 36% Complete Remission Rates In Annamycin Phase 2/3 Trial For Relapsed Or Refractory AML

First interim results from pivotal Phase 2/3 trial highlight encouraging remission rates in patients with relapsed or refractory AML

Moleculin Biotech, Inc. (NASDAQ:MBRX) ("Moleculin" or the "Company") today announced that an abstract highlighting data from its lead drug candidate, Annamycin, has been accepted for presentation at the 2026 American Society of Hematology (ASH) Annual Meeting, taking place December 12-15, 2026 in New Orleans, Louisiana.

The abstract, titled "A Pivotal Phase 2/3 Study of Naxtarubicin as Second Line Therapy in Patients with AML," presents results from the first prespecified interim analysis of the Company's pivotal MB-108 Phase 2/3 trial evaluating Annamycin in combination with cytarabine (Ara-C) in patients with relapsed or refractory (R/R) acute myeloid leukemia (AML).

Among the first 45 randomized patients evaluated, complete remission rates were 43% and 36% in the two Annamycin treatment arms, respectively, compared to 12% in the placebo arm. Consistent with findings across Annamycin's clinical development program to date, no signs, symptoms or echocardiographic findings suggestive of cardiotoxicity were observed through the data cutoff. All cardiac safety data will undergo independent expert and independent Data Monitoring Committee review at the second interim analysis. Following its review, the independent Data Monitoring Committee recommended that the study continue without amendment, with all three treatment arms maintained.

"We are encouraged by these initial findings from our pivotal Phase 2/3 trial, particularly the remission rates observed in the Annamycin treatment arms. The independent Data Monitoring Committee's recommendation to continue the study without modification represents an important milestone for the program. We look forward to sharing these findings with the broader hematology community at ASH as we continue advancing Annamycin's development for patients facing this challenging disease," commented Walter Klemp, Chairman and Chief Executive Officer of Moleculin.

The MIRACLE Trial (MB-108) is designed to confirm the efficacy and safety findings observed in the Company's completed MB-106 Phase 1/2 trial and, if successful, could support a New Drug Application submission, consistent with the Company's agreement with the U.S. Food and Drug Administration. As previously announced, the second interim analysis is expected in early 2027.