The European Commission (EC) has granted conditional approval to Jazz Pharmaceuticals’ Ziihera (zanidatamab) to treat a subset of advanced biliary tract cancer (BTC) patients.
The human epidermal growth factor receptor 2 (HER2)-targeted bispecific antibody has been authorised for use as a monotherapy in adults with unresectable locally advanced or metastatic HER2-positive (IHC 3+) BTC who have received at least one prior line of systemic therapy.
The EC’s decision was supported by results from the phase 2b HERIZON-BTC-01 trial, which included a cohort of 80 BTC patients with centrally confirmed HER2-positive tumours (cohort one).
The study met its primary endpoint of confirmed objective response rate (cORR) in cohort one, with Ziihera demonstrating a cORR of 41.3%, including two complete responses, at a median follow-up of 21.9 months. The median duration of response (DoR) was 14.9 months, and the median overall survival (OS) was 15.5 months.
Data from a pre-specified subgroup analysis in 62 patients with IHC 3+ tumours also showed that Ziihera demonstrated a cORR of 51.6%, with a median DoR of 14.9 months and median OS of 18.1 months.
BTCs, including gallbladder cancer and cholangiocarcinoma, are a rare and aggressive group of cancers that are often diagnosed at an advanced stage, when curative surgery is no longer an option.
Approximately 26% of BTC patients globally have HER2-positive disease, which is associated with poorer outcomes compared to HER2-negative disease.
Robert Iannone, executive vice president, global head of research and development, and chief medical officer of Jazz Pharmaceuticals, said the conditional approval “represents significant progress” for patients with advanced HER2-positive BTC.
“Ziihera is the first HER2-targeted therapy authorised in the EU specifically for this population, and the EC’s decision reflects both the strength of the HERIZON-BTC-01 data and the urgency for innovation in rare gastrointestinal cancers,” Iannone said.
In line with EC’s conditional approvals pathway, continued authorisation for Ziihera in this indication is contingent on the verification of clinical benefit in the ongoing phase 3 HERIZON-BTC-302 trial, which is evaluating the drug in combination with standard-of-care therapy in the first-line setting for patients with HER2-positive BTC.
