Moleculin Biotech Publishes Annamycin Cardiac Safety Study

Moleculin Biotech announced the publication of an abstract at the European Hematology Association 2026 Congress highlighting the cardiac safety profile of Annamycin, the Company's next-generation anthracycline currently in late-stage development for the treatment of relapsed/refractory acute myeloid leukemia. The abstract titled, "Cardiac Safety of L-Annamycin Across High Cumulative Anthracycline Exposure: Implications for Relapsed/Refractory AML," will highlight pooled cardiac safety findings from five completed clinical trials evaluating Annamycin in heavily pretreated patients, including those with substantial prior anthracycline exposure. Importantly, the analysis demonstrated no clinically significant treatment-related cardiotoxicity across cumulative anthracycline-equivalent doses that exceeded conventional lifetime exposure limits associated with traditional anthracyclines. Anthracyclines remain among the most effective agents in AML treatment, but their clinical utility is constrained by cumulative cardiac toxicity. This limitation is especially relevant in R/R AML, where patients often have prior anthracycline exposure and where currently available salvage therapies following venetoclax-based treatment have demonstrated limited efficacy. The independent cardiac review, conducted by a cardio-oncology laboratory at the Cleveland Clinic, analyzed comprehensive cardiac monitoring data from 90 patients treated with Annamycin. Among 78 patients with source-data verified pre- and post-treatment ejection fraction assessments, no patients met criteria for clinically significant left ventricular dysfunction. Mean ejection fraction remained stable, and no association was observed between cumulative dose and cardiac function decline. Additional analyses of serial ECGs, troponins, and global longitudinal strain assessments similarly demonstrated no evidence of drug-induced cardiotoxicity. Management believes these findings reinforce Annamycin's potential to address a major unmet need in R/R AML by enabling continued anthracycline-based treatment without the cumulative cardiac limitations commonly associated with conventional agents.