Moleculin Announces Imminent MIRACLE Trial Unblinding as Blinded Data Continue to Significantly Outperform Historical Benchmarks

On May 13, 2026 Moleculin Biotech, Inc., (Nasdaq: MBRX) ("Moleculin" or the "Company"), reported that it is approaching the first unblinding of data from its pivotal Phase 2B/3 "MIRACLE" trial evaluating Annamycin in combination with cytarabine for the treatment of subjects that have been relapsed or refractory to their primary line of treatment for acute myeloid leukemia (R/R AML). The trial incorporates two arms of Annamycin at different doses plus cytarabine compared to the control arm of cytarabine plus a placebo. The Company continues to expect this unblinding to occur prior to June 30, 2026, as previously communicated.

Schedule your 30 min Free 1stOncology Demo!
Discover why more than 1,500 members use 1stOncology™ to excel in:

Early/Late Stage Pipeline Development - Target Scouting - Clinical Biomarkers - Indication Selection & Expansion - BD&L Contacts - Conference Reports - Combinatorial Drug Settings - Companion Diagnostics - Drug Repositioning - First-in-class Analysis - Competitive Analysis - Deals & Licensing

                  Schedule Your 30 min Free Demo!

The Company also reported that preliminary blinded efficacy data for the 45 subjects continue to approximate previously disclosed results, including a composite complete remission rate (CRc) exceeding 40% and a complete remission (CR) rate of approximately 30%. These results compare favorably to historical CR rates from two major trials of approximately 17-18% observed with cytarabine alone in similar patient populations. Cytarabine is a currently approved standard of care for second line treatment of AML. Based on preliminary data, the median age for subjects enrolled is in the mid-60’s, with over 30% entering the trial after becoming relapsed from or refractory (R/R) to a prior venetoclax regimen as first line therapy, which is considered a particularly challenging patient group. As of May 1st, a total of 56 subjects have been recruited in the MIRACLE trial to date keeping the Company on track to recruit the 90th subject in Part A in Q3 2026.

"The data coming from MIRACLE is encouraging" said Walter Klemp, Chairman and CEO of Moleculin. "For decades, cytarabine monotherapy regimens, although one of the current standards of care, have set a relatively low bar in relapsed or refractory AML, with historical complete remission rates hovering around 17-18% in previously referenced clinical trials. With our trial comparing two arms of Annamycin in combination with cytarabine compared to cytarabine with a placebo, we are looking forward to the opportunity of showing Annamycin is additive to cytarabine alone in a head to head trial. Against this backdrop, the data emerging from MIRACLE highlight what could be a substantial advancement, suggesting that we may finally be moving beyond the limitations that have defined standard-of-care outcomes."

MIRACLE Trial Progress and Next Steps

The MIRACLE study (derived from Moleculin R/R AML AnnAraC Clinical Evaluation) is a Phase 2B/3, global multi-center, randomized, double-blind, placebo-controlled, adaptive designed clinical trial whereby data from the 2B (Part A) portion will be combined with the Phase 3 (Part B) portion for purposes of measuring its primary efficacy endpoint. Part A of the MIRACLE trial is designed to evaluate the effectiveness of Annamycin in two dosing arms (190 mg/m² and 230 mg/m²) in combination with cytarabine (also referred to as Ara-C) as compared to a control arm of cytarabine plus placebo. The protocol for the MIRACLE trial allows for the unblinding of preliminary primary efficacy data of the three arms at 45 subjects in Part A, in addition to the conclusion of Part A (at 90 total subjects). The first early unblinding should yield approximately 30 subjects treated with Annamycin (190 mg/m2 and 230 mg/m2) in combination with cytarabine and 15 subjects treated with just cytarabine plus placebo. The MIRACLE trial is being offered only to AML patients who have had a single prior induction therapy (2nd line patients or 2L) including subjects that were treated with a Venetoclax regimen.

The unblinding of the first 45 subjects is on track to occur in late Q2 2026, as the data are subject to final data entry and audit. The second group of 45 subjects in Part A are expected to be fully recruited in the third quarter of 2026 with unblinding expected late in the second half of 2026. Recruitment of the second group of 45 subjects in Part A will continue uninterrupted while the first 45 subjects with efficacy are being unblinded. Unblinding for the full 90 subjects in Part A may require more time than for the first 45 as it involves more data to support the transition from Part A to Part B.

For more information about the MIRACLE trial, visit clinicaltrials.gov and reference identifier NCT06788756. Additionally, the clinical trial in the EU can be found on euclinicaltrials.eu and the reference identifier is 2024-518359-47-00.

Annamycin, also known by its non-proprietary name of naxtarubicin, 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. Annamycin also benefits from composition of matter patent protection through 2040 with the potential to extend that protection as far as 2045. Furthermore, Annamycin has Orphan Drug Designation for the treatment of relapsed or refractory acute myeloid leukemia from the EMA.

(Press release, Moleculin, MAY 13, 2026, View Source [SID1234665635])