Zymeworks Inc. — Form 8-K

Jazz Pharmaceuticals received FDA approval for Ziihera (zanidatamab) in first-line HER2+ gastroesophageal adenocarcinoma, both with and without tislelizumab plus chemotherapy. Zymeworks receives a $250M milestone payment from Jazz (total upfront+milestones: $650M) and remains eligible for up to $1.3B additional milestones plus 10–20% tiered royalties. This is zanidatamab's second FDA approval in less than two years; separately, BeOne collaboration has yielded $81M to date with up to $144M additional milestones plus up to 19.5% royalties.