8-K: Moleculin Biotech Reports 60% Enrollment in AML Trial

Moleculin Biotech announced 60% enrollment for the first interim unblinding of its pivotal Phase 2B/3 MIRACLE study of Annamycin for relapsed/refractory AML, with initial data expected in Q1 2026.

Summary

• Moleculin Biotech, Inc. (MBRX) reported 60% enrollment for the first planned interim unblinding of data in its pivotal Phase 2B/3 MIRACLE study.
• The study evaluates Annamycin in combination with cytarabine for adult patients with acute myeloid leukemia (AML) who are refractory to or relapsed after induction therapy (R/R AML).
• The target for the first unblinding is 45 subjects, with 60% (27 subjects) having consented as of November 4, 2025.
• Completion of treatment for the first 45 subjects is expected in the first quarter of 2026, with initial unblinding of data thereafter.
• Blinded response activity is tracking within the expected range based on historical responses of the trial arm equivalents.
• The MIRACLE study is a global multi-center, randomized, double-blind, placebo-controlled, adaptive designed clinical trial.
• The first early unblinding will involve 30 subjects treated with Annamycin (190mg/m2 and 230 mg/m2) plus HiDAC and 15 subjects treated with HiDAC plus placebo.
• A second unblinding is expected in the first half of 2026.
• Annamycin has Fast Track Status and Orphan Drug Designation from the FDA for R/R AML and Orphan Drug Designation for soft tissue sarcoma.
• Annamycin also has Orphan Drug Designation for R/R AML from the EMA.
• Composition of matter patent protection for Annamycin extends through 2040, with potential to extend that protection as far as 2045.

Sentiment

Score: 6

Explanation: The progress in enrollment and positive blinded response activity are encouraging, and the accelerated timeline for the second unblinding is a positive. However, the mention of bed shortages, holiday-related slowdowns, and the explicit need for significant, uncommitted additional financing introduce notable caution and risk.

Positives

• 60% of the target 45 subjects for the first interim unblinding have consented, indicating strong recruitment momentum.
• Blinded response activity is tracking within the expected range, suggesting potential efficacy.
• Annamycin has Fast Track Status and Orphan Drug Designation from the FDA and EMA for R/R AML, which can accelerate development and market access.
• Composition of matter patent protection for Annamycin extends through 2040, with potential to 2045, providing long-term market exclusivity.
• The accelerated estimated timeline for the second unblinding (first half of 2026) is due to positive investigator response.

Negatives

• Enrollment at some sites in Europe has been impacted by bed shortages, which could potentially slow overall progress.
• Upcoming holidays are expected to slow treatment of enrolled subjects, pushing completion of the first 45 subjects into Q1 2026.
• The company will require significant additional financing, for which it has no commitments, to conduct its clinical trials as described.

Risks

• The company will require significant additional financing, for which it has no commitments, to conduct its clinical trials.
• Expectations regarding forward-looking statements may prove to be materially different from actual results due to known and unknown risks and uncertainties.
• Enrollment at some sites in Europe has been impacted by bed shortages, which could affect recruitment timelines.
• Upcoming holidays are expected to slow treatment of enrolled subjects.

Future Outlook

Moleculin Biotech expects to complete treatment of the first 45 subjects in its MIRACLE study in the first quarter of 2026, with initial unblinding of data thereafter. A second unblinding is anticipated in the first half of 2026. The company believes Annamycin has the potential to offer a safer and more effective treatment option for R/R AML patients. However, significant additional financing is required to conduct clinical trials, for which there are no current commitments.

Management Comments

• "We're very encouraged by the strong momentum in recruitment and enthusiasm I've personally heard from investigators around Europe and the US." Walter Klemp, Chairman and CEO.
• "To date, we are seeing blinded response activity tracking within our expected range, based on historical responses of the trial arm equivalents." Walter Klemp, Chairman and CEO.
• "Although enrollment at some sites in Europe has been impacted by bed shortages, the MIRACLE study continues to progress as planned." Walter Klemp, Chairman and CEO.
• "As we move toward our first unblinding milestone, we are excited about Annamycin's potential to fill a major gap in AML treatment." Walter Klemp, Chairman and CEO.
• "We believe we're well on our way to determining if Annamycin has the potential to offer a much-needed, safer, and more effective option for patients facing this devastating disease." Walter Klemp, Chairman and CEO.

Industry Context

The development of Annamycin addresses a critical unmet need in the treatment of relapsed or refractory acute myeloid leukemia (AML), a devastating disease. The drug's design to avoid multidrug resistance and lack cardiotoxicity positions it as a potentially differentiated option compared to existing anthracyclines. Its Fast Track and Orphan Drug designations highlight the significant medical need and potential for expedited regulatory review, which is common for therapies targeting rare or severe conditions with limited treatment options.

Comparison to Industry Standards

• Annamycin is designed to avoid multidrug resistance mechanisms and lack the cardiotoxicity common with currently prescribed anthracyclines, potentially offering a safer profile compared to standard chemotherapy agents like doxorubicin or daunorubicin.
• The MIRACLE trial's adaptive design, combining Phase 2B and Phase 3 data, is a modern approach to clinical development, aiming for efficiency in bringing new therapies to market, similar to strategies employed by other oncology drug developers.
• The Fast Track and Orphan Drug Designations from the FDA and EMA for Annamycin for R/R AML are comparable to designations received by other innovative oncology drugs addressing high unmet needs, such as venetoclax (Venclexta) for AML, which also received similar designations.

Stakeholder Impact

• Shareholders: Potential for increased value if Annamycin's trial results are positive, but also risk from the need for significant additional financing and potential dilution.
• Patients (R/R AML): Potential for a new, safer, and more effective treatment option for a devastating disease with high unmet need.
• Investigators/Clinical Sites: Continued engagement in a pivotal trial, contributing to medical advancement.
• Employees: Continued work on a promising drug candidate, but also potential uncertainty related to future financing.

Next Steps

• Continue identification and recruitment of subjects for the MIRACLE study.
• Complete treatment of the first 45 subjects in the MIRACLE study (expected Q1 2026).
• Conduct initial unblinding of data for the first 45 subjects (expected after Q1 2026).
• Conduct the second unblinding of data (expected in the first half of 2026).
• Audit, lock, and review unblinded data prior to release.
• Secure significant additional financing to fund ongoing clinical trials.

Key Dates

Recommendation

While the clinical trial progress with 60% enrollment and positive blinded response activity is encouraging for Annamycin's potential, the explicit disclosure of a need for significant, uncommitted additional financing introduces a material risk of dilution or operational delays. The minor delays due to bed shortages and holidays, while not critical, add to the uncertainty. Investors should hold to await the initial unblinded data in Q1 2026 and further clarity on the company's financing strategy before making further investment decisions.

Keywords

Moleculin Biotech, MBRX, Annamycin, AML, Acute Myeloid Leukemia, MIRACLE study, Phase 2B/3, Clinical Trial, Oncology, Hematology, Orphan Drug, Fast Track, Cytarabine, R/R AML