Zymeworks said its partner Jazz Pharmaceuticals won U.S. FDA approval for two first-line Ziihera regimens in HER2-positive advanced gastroesophageal adenocarcinoma, triggering a $250 million milestone payment to Zymeworks.
The approval covers: Ziihera plus tislelizumab and fluoropyrimidine and platinum-containing chemotherapy for HER2+ IHC 3+ and IHC 2+/ISH+ disease Ziihera plus fluoropyrimidine and platinum-containing chemotherapy for HER2+ IHC 3+ disease
The company said this is the second FDA approval for zanidatamab in less than two years, following its earlier accelerated approval in biliary tract cancer.
Financially, the new approval lifted total upfront and milestone payments Zymeworks has received from Jazz to $650 million, up from $400 million before this latest payment. Zymeworks still can receive up to $1.3 billion more from Jazz in regulatory and commercial milestones, plus tiered royalties of 10% to 20% on Jazz net sales in Jazz’s territories.
Under its separate BeOne collaboration, Zymeworks said it has received $81 million to date and remains eligible for up to $144 million in additional milestones, plus tiered royalties of up to 19.5%.
On the clinical side, the company pointed to the phase 3 HERIZON-GEA-01 trial, which it said showed a median overall survival of more than two years. It also said similar outcomes were seen regardless of PD-L1 status.
Zymeworks said the approval supports its cash flow strategy and its investment in wholly owned programs, including trispecific T-cell engagers and antibody-drug conjugates. The market has reacted to these announcements by moving the company's shares 3.34% to a price of $29.73. For more information, read the company's full 8-K submission here.
