Moleculin Doses First Patient in Pivotal Adaptive Phase 3 MIRACLE Trial

Moleculin Biotech, Inc. recently announced the first patient has been dosed in its Phase 3 pivotal trial evaluating Annamycin in combination with Cytarabine (also known as Ara-C and for which the combination of Annamycin and Ara-C is referred to as AnnAraC) for the treatment of AML patients who are refractory to or relapsed after induction therapy (R/R AML). This Phase 3 MIRACLE trial (derived from Moleculin R/R AML AnnAraC Clinical Evaluation) is a global approval trial, including sites in the US, Europe, and the Middle East.

“The start of patient dosing represents a huge milestone for Moleculin and importantly, the AML community,” commented Walter Klemp, Chairman and Chief Executive Officer of Moleculin. “Our team remains focused on bringing clinical sites online in the U.S., Europe and Middle East and enrolling patients to build on this momentum. With the progress made to date, we expect to unblind preliminary data from the first 45 subjects in the second half of this year, a near-term, potentially value-driving milestone that will provide key insight as we continue to advance Annamycin’s development towards approval.”

The MIRACLE study is a Phase 2B/3 clinical trial whereby data from the 2B portion will be combined with the Phase 3 portion for purposes of measuring its primary endpoint. MIRACLE is subject to appropriate future filings with and potential additional feedback from the FDA and their foreign equivalents, utilizes an adaptive design whereby the first 75 to 90 subjects will be randomized (1:1:1) in Part A of the trial to receive high dose cytarabine (HiDAC) combined with either placebo, 190 mg/m2 of Annamycin, or 230 mg/m2 of Annamycin, which Annamycin doses were specifically recommended by the FDA in the Company’s end of Phase 1B/2 meeting.

The protocol for the MIRACLE trial allows for the unblinding of preliminary primary efficacy data (Complete Remission or CR) and safety/tolerability of the three arms at 45 subjects, in addition to the conclusion of Part A (at 75 to 90 subjects). The first early unblinding will yield 30 subjects treated with Annamycin (190mg/m2 and 230/m2) and HiDAC and 15 subjects treated with just HiDAC. The Company expects to reach the first unblinding (45 subjects) in the second half of 2025, in addition to the second unblinding, which is expected in the first half of 2026. This accelerated estimated timeline is due in part to the positive response the Company received in meetings during December with potential investigators regarding recruitment for the trial.

For Part B of the trial, approximately 220 additional subjects will be randomized to receive either HiDAC plus placebo or HiDAC plus the optimum dose of Annamycin (randomized 1:1). The selection of the optimum dose will be based on the overall balance of safety, pharmacokinetics and efficacy, consistent with the FDA’s new Project Optimus initiative.

For more information about the MIRACLE trial, visit clinicaltrials.gov and reference identifier NCT06788756.

Annamycin currently has Fast Track Status and Orphan Drug Designation from the FDA for the treatment of relapsed or refractory acute myeloid leukemia, in addition to Orphan Drug Designation for the treatment of soft tissue sarcoma. Furthermore, Annamycin has Orphan Drug Designation for the treatment of relapsed or refractory acute myeloid leukemia from the European Medicines Agency (EMA).

Moleculin Biotech, Inc. is a Phase 3 clinical stage pharmaceutical company advancing a pipeline of therapeutic candidates addressing hard-to-treat tumors and viruses. The Company’s lead program, Annamycin, is a next-generation anthracycline designed to avoid multidrug resistance mechanisms and to eliminate the cardiotoxicity common with currently prescribed anthracyclines. Annamycin is currently in development for the treatment of relapsed or refractory acute myeloid leukemia (AML) and soft tissue sarcoma (STS) lung metastases.

The Company is initiating the MIRACLE (Moleculin R/R AML AnnAraC Clinical Evaluation) Trial (MB-108), a pivotal, adaptive design Phase 3 trial evaluating Annamycin in combination with cytarabine, together referred to as AnnAraC, for the treatment of relapsed or refractory acute myeloid leukemia. Following a successful Phase 1B/2 study (MB-106), with input from the FDA, the Company believes it has substantially de-risked the development pathway towards a potential approval for Annamycin for the treatment of AML. This study is subject to appropriate future filings with potential additional feedback from the FDA and their foreign equivalents.

Additionally, the Company is developing WP1066, an Immune/Transcription Modulator capable of inhibiting p-STAT3 and other oncogenic transcription factors while also stimulating a natural immune response, targeting brain tumors, pancreatic and other cancers. Moleculin is also engaged in the development of a portfolio of antimetabolites, including WP1122 for the potential treatment of pathogenic viruses, as well as certain cancer indications. For more information, visit www.moleculin.com.