Arvinas, Pfizer Plan To Broaden Development Of Breast Cancer Candidate

Arvinas Inc ARVN and Pfizer Inc PFE released clinical data for vepdegestrant (ARV-471) in combination with palbociclib (IBRANCE). 

Interim results from the Phase 1b combination cohort demonstrate encouraging clinical activity in heavily pre-treated patients with a median of four lines of therapy across disease settings with locally advanced or metastatic ER positive/human epidermal growth factor 2 (HER2) negative (ER+/HER2-) breast cancer. 

A clinical benefit rate (CBR) of 63% or 29/46 patients; at the RP3D of 200 mg (n=21), the CBR was 67% or 14/21 patients.

An objective response rate (ORR) in evaluable patients with measurable disease at baseline (n=31) of 42% or 13/31 patients; at the RP3D of 200 mg (n=15), the ORR was 53%.

Median progression-free survival (PFS) of 11.1 months; 22 of 46 patients across all doses had progression events by the time of data cutoff.

Pending additional data and agreement with regulatory authorities, Arvinas and Pfizer plan to broaden the development of vepdegestrant to include new combinations with cyclin-dependent kinase (CDK) inhibitors in both the first- and second-line settings. 

The companies plan to initiate a new second-line Phase 3 trial of vepdegestrant in combination with palbociclib and potentially other CDK4/6 inhibitors and a new first-line Phase 3 trial of vepdegestrant plus Pfizer's CDK4 inhibitor (PF-07220060).

Price Action: PFE stock is up 0.28% at $29.17 during the premarket session on the last check Wednesday. ARVN shares are up 3.63% at $24.01.