Health care stocks were flat to higher premarket Tuesday, with the iShares Biotechnology ETF (IBB) inactive and the State Street Health Care Select Sector SPDR ETF (XLV) advancing by 0.7%.

Amylyx Pharmaceuticals (AMLX) shares rose more than 34% after the company said its investigational post-bariatric hypoglycemia treatment Avexitide met its primary endpoint in a phase 3 clinical trial.

Immatics (IMTX) stock was down more than 4% after the company reported a wider-than-expected Q2 net loss, as revenue also missed analysts' estimates.

BlossomHill Therapeutics (BLSM) shares were up more than 3% after the company said the US FDA has granted fast track designation for BH-30643 in advanced or metastatic non-small cell lung cancer following prior treatment with a third-generation EGFR tyrosine kinase inhibitor.