MIRM · Mirum Pharmaceuticals, Inc.

This 8-K discloses statistically and clinically meaningful topline efficacy and safety results from the Phase 2b portion of the AZURE-1 study evaluating brelovitug in chronic hepatitis delta virus (HDV), a severe, life-threatening liver disease with no approved therapies. The primary composite endpoint—virologic response plus ALT normalization—was met in 45% and 35% of patients receiving brelovitug 300 mg weekly and 900 mg every four weeks, respectively, compared to zero in the delayed-treatment control group. Virologic response alone reached 100% in the higher-frequency dosing arm, underscoring dose-dependent antiviral potency. Safety data show no treatment-related serious adverse events, Grade 3+ events, or discontinuations, with only mild, transient injection site reactions and flu-like symptoms reported. These results de-risk the ongoing Phase 3 program and materially advance brelovitug’s development path: topline data from both Phase 3 trials (AZURE-1 and AZURE-4) are expected in the second half of 2026, positioning Mirum for a Biologics License Application submission in the U.S. in 2027. Given the absence of approved HDV therapies and the high unmet medical need, successful execution of this development plan could establish brelovitug as a foundational monotherapy and represent a major inflection point for Mirum’s valuation and commercial trajectory.