Mirum says brelovitug hits primary endpoint in Phase 3 AZURE-4 trial for hepatitis delta

Mirum Pharmaceuticals announced on November 10, 2026 that the Phase 3 AZURE-4 study evaluating brelovitug, an investigational fully human monoclonal antibody that binds to hepatitis B surface antigen, met its primary endpoint in patients with chronic hepatitis delta virus.¹ The company said AZURE-4 is the second of two Phase 3 studies that will form the basis of its U.S. registration package for brelovitug.¹ Mirum also presented additional data at the AASLD Liver Meeting, which the company said showed deepening viral suppression, increased rates of ALT normalization, and improvements in liver stiffness with longer treatment, including in patients with advanced cirrhosis.¹

The trial randomized 113 treatment-naive patients in a 2:1:1 ratio to brelovitug 300 mg once weekly by subcutaneous injection, brelovitug 900 mg every four weeks by subcutaneous injection, or a delayed-treatment arm starting at Week 12.¹ The enrolled population had notable illness severity, with roughly half of patients carrying high viral loads and over half having cirrhosis, and average liver enzyme levels above normal at baseline.

At Week 24, 59% of patients on 300 mg once weekly and 44% on 900 mg every four weeks achieved the combined endpoint of virologic response and ALT normalization, versus 0% in the delayed-treatment group (p≤0.0001 for both comparisons).¹

On safety, Mirum reported that brelovitug was generally tolerated well across dose groups with no new safety signals, the most frequent side effect being flu-like symptoms in 17.2% and 18.5% of the 300 mg and 900 mg groups respectively, mostly after the first dose, with injection site reactions occurring in 1.7% and 7.4% of patients.¹

Mirum said it intends to submit a Biologics License Application to the FDA in the first half of 2027, with a potential U.S. launch in the fourth quarter of 2027, if approved.¹