Jazz secures FDA approval for Ziihera in first-line HER2-positive GEA

Jazz Pharmaceuticals has been granted US approval for two combinations of its cancer drug Ziihera for people with advanced HER2-positive gastroesophageal adenocarcinoma.

The FDA’s decision clears Ziihera for use as a first-line treatment in combination with BeOne Medicines’ PD-1 inhibitor Tevimbra (tislelizumab-jsgr) and fluoropyrimidine- and platinum-based chemotherapy for patients with HER2-positive tumours that are IHC 3+ or IHC 2+/ISH+. Ziihera can also be used with chemotherapy alone in patients with IHC 3+ disease.

"This approval is a major step forward for people with HER2+ advanced GEA. Ziihera is now the first and only bispecific HER2-targeted antibody combined with a PD-1 inhibitor and chemotherapy approved for all HER2+ advanced GEA patients, regardless of PD-L1 status, establishing a new standard of care in first-line treatment," said Rob Iannone, MD, MSCE, executive vice president, global head of research and development, and chief medical officer of Jazz Pharmaceuticals.

He added: "The HERIZON-GEA-01 results include the longest median overall survival reported in a Phase 3 trial in this setting, at 26.4 months. We are grateful to the gastric cancer community, including patients, caregivers, investigators, and advocacy organisations, whose partnership made this possible."

Support for the approval was based on results from the Phase 3 HERIZON-GEA-01 trial, which compared the Ziihera combinations with the existing standard of care – HER2-targeted treatment trastuzumab plus chemotherapy.

Results of the study showed that both Ziihera regimens improved progression-free survival, cutting the risk of disease progression or death by 35%. Median progression-free survival was 12.4 months, compared with 8.1 months for patients receiving trastuzumab and chemotherapy.

The Ziihera, Tevimbra, and chemotherapy combination also delivered an overall survival benefit. Median overall survival reached 26.4 months, compared with 19.2 months for the trastuzumab regimen, translating into a 28% reduction in the risk of death.

The results were broadly consistent across several groups of patients, including those whose tumours were positive or negative for PD-L1.

The FDA clearance adds another approved use for Ziihera, which was first approved in the US in 2024 for previously treated, unresectable locally advanced or metastatic HER2-positive biliary tract cancer.

The HERIZON-GEA-01 trial is continuing, with further analyses planned.