Moleculin Biotech, Inc. (Nasdaq: MBRX) announced on September 28, 2026, the publication of a peer-reviewed analysis regarding the cardiac safety of its drug candidate Annamycin (also known as L-Annamycin or naxtarubicin). The analysis, titled "Cardiac safety of L-Annamycin: a pooled analysis of five clinical trials," was published in the journal Frontiers in Cardiovascular Medicine.
The report details cardiac safety findings from 90 patients treated across five clinical trials focused on acute myeloid leukemia (AML) and metastatic soft tissue sarcoma (STS). The analysis was independently evaluated by a cardio-oncology laboratory at the Cleveland Clinic.
Key findings from the study include:
- Mean LVEF Stability: Mean Left Ventricular Ejection Fraction (LVEF) was 60.6% at baseline and 60.0% following treatment, with no statistically significant difference (p=0.84).
- Dose Independence: There was no association found between cumulative Annamycin exposure and changes in LVEF, nor was patient age associated with changes in cardiac function.
- Biomarker Results: Serial electrocardiograms (ECGs), cardiac biomarkers including troponin I/T, and global longitudinal strain assessments showed no evidence of treatment-related cardiotoxicity.
- High Cumulative Exposure: Patients received a median cumulative Annamycin dose of 660 mg/m². The findings were observed despite cumulative exposures exceeding traditional lifetime limits for conventional anthracyclines.
The authors concluded that Annamycin was not associated with clinical or subclinical evidence of cardiotoxicity at cumulative doses exceeding traditional anthracycline thresholds. The company stated that these findings support the continued clinical evaluation of Annamycin as a potentially safer anthracycline platform.
Annamycin is currently being evaluated in Moleculin’s MIRACLE clinical development program for patients with relapsed or refractory AML.
