09:17 AM EDT, 08/19/2025 (MT Newswires) -- Health care stocks were flat to higher premarket Tuesday, with the iShares Biotechnology ETF (IBB) inactive and the Health Care Select Sector SPDR Fund ( XLV ) up 0.1%.

Medtronic ( MDT ) shares were down more than 5% after the company said its board has appointed two new independent directors and created two new committees following "constructive dialogue" with Elliott Investment Management. Medtronic ( MDT ) also reported higher fiscal Q1 non-GAAP earnings and adjusted revenue, and raised its fiscal 2026 guidance for adjusted earnings per share.

PTC Therapeutics ( PTCT ) shares declined by more than 5% after the company said it had received a Complete Response Letter from the US Food and Drug Administration regarding its New Drug Application for vatiquinone to treat Friedreich's ataxia. The company said the regulator stated in the letter that vatiquinone did not demonstrate substantial evidence of efficacy.

Viking Therapeutics ( VKTX ) stock fell by more than 37% even after the company said its experimental obesity drug VK2735 led to a significant mean weight loss of up to 12.2% from baseline in a 13-week phase 2 study.