Health care stocks rose Tuesday afternoon, with the NYSE Health Care Index adding 0.4% and the Health Care Select Sector SPDR Fund (XLV) up 0.2%.

The iShares Biotechnology ETF (IBB) shed 0.3%.

In corporate news, Arrowhead Pharmaceuticals (ARWR) shares jumped past 16%. The company signed a global licensing and partnership agreement with Sarepta Therapeutics (SRPT) to develop new therapies for genetic diseases of the muscle, central nervous system and lungs. Sarepta shares climbed more than 12%.

Amgen (AMGN) shares tumbled 7.7%. The company said a phase 2 trial showed that its investigational obesity drug MariTide demonstrated up to 20% average weight loss after a year in people living with obesity or overweight without type 2 diabetes. Mizuho said in a note that this efficacy is "on the low end of expectations."

The White House said Tuesday it's proposing a new rule to expand coverage of anti-obesity and diabetes medications made by companies such as Novo Nordisk (NVO) and Eli Lilly (LLY) for Americans with Medicare or Medicaid. Novo shares rose 1.5%, and Eli Lilly popped 5.3%.