09:10 AM EDT, 05/16/2024 (MT Newswires) -- Health care stocks were steady premarket Thursday, with the iShares Biotechnology ETF ( IBB ) inactive and the Health Care Select Sector SPDR Fund ( XLV ) up 0.1%.

Arvinas ( ARVN ) shares were up more than 6% after the company and Pfizer ( PFE ) said updated data from a phase 1b study evaluating metastatic breast cancer drug candidate vepdegestrant in combination with palbociclib for the treatment of advanced breast cancer demonstrated encouraging clinical activity.

Biogen (BIIB) and Ionis Pharmaceuticals ( IONS ) said they would cease development of BIIB105 after a phase 1/2 study showed the investigational ALS drug did not slow disease progression. Biogen stock was more than 1% lower in recent Thursday premarket activity.

Johnson & Johnson ( JNJ ) said it has signed a definitive agreement to acquire Proteologix, a private biotechnology company, for $850 million in cash. Johnson & Johnson ( JNJ ) shares were up 0.1% in recent Thursday premarket activity.