Win For Pfizer? Seagen's Cancer Combo Therapy Hits Primary Goal In Late-Stage Breast Cancer Study

Seagen Inc SGEN announced that the Phase 3 HER2CLIMB-02 clinical trial of Tukysa (tucatinib) in combination with the antibody-drug conjugate ado-trastuzumab emtansine (Kadcyla) met its primary endpoint of progression-free survival (PFS). 

Patients in the trial had unresectable locally advanced or metastatic human epidermal growth factor receptor 2-positive (HER2-positive) breast cancer and had received previous treatment with a taxane and trastuzumab.​ 

Overall survival (OS) data, a secondary endpoint, are not yet mature. Discontinuations due to adverse events were more common in the combination arm of the trial, but no new safety signals emerged for the combination.

Pfizer Inc PFE has agreed to acquire Seagen in a $43 billion deal to gain access to its targeted cancer therapies.

Tukysa is currently approved in the U.S. in combination with trastuzumab and capecitabine for adult patients with advanced unresectable or metastatic HER2-positive breast cancer, including patients with brain metastases, who have received one or more prior anti-HER2-based regimens in the metastatic setting. 

Price Action: SGEN shares are down 0.11% at $193.98 on the last check Wednesday.