Moleculin Achieves 45-Subject Enrollment Milestone in MIRACLE Trial Ahead of June Interim Unblinding

Moleculin Biotech's MIRACLE trial is approaching its first interim unblinding in June 2026, a checkpoint that will give formulation and clinical development teams their earliest unblinded signal on whether Annamycin's cardiotoxicity profile holds in a relapsed/refractory AML population. The 45-subject enrollment threshold triggering that analysis has been confirmed, with the 90th subject expected in Q3 2026.

The blinded composite complete remission rate has held at 40% across both the 30-subject and 45-subject marks, a consistency that, while still blinded, sustains the efficacy hypothesis for AnnAraC (Annamycin plus cytarabine) in adult patients who have exhausted standard anthracycline-based options. For development teams tracking next-generation anthracyclines, the cardiotoxicity angle carries direct formulation implications: if unblinded data confirm reduced cardiac burden, the compound's lifetime dose ceiling would differ materially from doxorubicin-class agents, altering both dosing regimen design and the patient eligibility criteria written into future protocols.

Moleculin's development timeline projects Part B enrollment beginning in 2H 2026, primary efficacy data for second-line AML subjects in 2028, and the start of a rolling NDA submission targeting accelerated approval on complete remission as the primary endpoint, also in 2028. Regulatory affairs teams monitoring the accelerated approval pathway will note that the adaptive Phase 2B/3 design means interim data packages will accumulate incrementally, each requiring contemporaneous documentation discipline consistent with 21 CFR Part 312 IND maintenance obligations.

R&D expenditure rose to $5.4 million in Q1 2026 from $3.4 million in Q1 2025, with $1.4 million of the $2.0 million increase attributable to European MIRACLE trial operations, a geographic expansion that introduces multi-site GMP comparability considerations for Annamycin supply and investigational product release. Moleculin raised approximately $8.3 million in gross proceeds during the quarter to sustain near-term operating runway through these milestones.

The June interim unblinding will be the first opportunity to assess whether the blinded efficacy trend survives statistical scrutiny, setting the trajectory for Part B design decisions and the eventual NDA package.

Source: Moleculin Biotech, Inc. via GlobeNewswire, May 15, 2026.