The BioPharm Brief: New Approvals and a Rare-Disease Milestone

Welcome to The BioPharm Brief, your daily snapshot of developments shaping the biopharmaceutical industry.

It’s a busy day for FDA action, with two approvals and a new designation spanning cancer, autoimmune disease, and rare disease. Here’s what we have today.

First, Zymeworks’ Ziihera has won FDA approval for first-line HER2-positive gastroesophageal adenocarcinoma. The approval covers two Ziihera-based regimens for adults with unresectable, locally advanced or metastatic HER2-positive disease. One combines Ziihera with tislelizumab and chemotherapy for HER2-positive tumors regardless of PD-L1 status, while the other combines Ziihera with chemotherapy for HER2 IHC 3+ disease. The decision was supported by Phase 3 HERIZON-GEA-01 data, in which the Ziihera, tislelizumab, and chemotherapy combination reduced the risk of death by 28% compared with trastuzumab plus chemotherapy and produced a median overall survival of 26.4 months. The approval also triggers a $250 million milestone payment to Zymeworks from Jazz Pharmaceuticals.

Next, Johnson & Johnson’s IMAAVY has become the first FDA-approved treatment specifically for warm autoimmune hemolytic anemia. The FcRn-blocking antibody, Imaavy, is approved for adults and patients 12 and older with warm autoimmune hemolytic anemia who are currently or previously treated with corticosteroids. The approval was supported by Phase 2/3 ENERGY data showing durable hemoglobin responses and reduced fatigue compared with placebo. Imaavy works by reducing circulating pathogenic IgG autoantibodies, targeting a key driver of the disease rather than broadly suppressing the immune system.

And Mahzi Therapeutics’ MZ-1866 has received FDA Rare Pediatric Disease Designation for Pitt Hopkins syndrome. The investigational AAV9 gene replacement therapy delivers functional copies of TCF4, the gene underlying the rare neurodevelopmental disorder. The designation comes as Mahzi’s Phase 1/2 UNITE study passes 50% enrollment, with seven of 12 planned participants enrolled. The company says the study is expected to complete enrollment by the end of 2026. If a qualifying therapy ultimately receives approval, the Rare Pediatric Disease designation can make it eligible for a Priority Review Voucher.

That’s The BioPharm Brief for today. For analysis and expert insights, please visit BioPharmInternational.com.

Key takeaways:

• Ziihera gains a first-line FDA approval in HER2-positive gastroesophageal cancer.
• J&J’s IMAAVY becomes the first approved treatment specifically for warm autoimmune hemolytic anemia.
• Mahzi’s MZ-1866 receives Rare Pediatric Disease Designation as its Pitt Hopkins gene therapy advances through Phase 1/2.