Healthcare stocks edged down Thursday afternoon, with the NYSE Healthcare Index easing 0.1% and the State Street Healthcare Select Sector SPDR ETF (XLV) fractionally lower.
The iShares Biotechnology ETF (IBB) decreased 0.6%.
In corporate news, Biogen (BIIB) shares fell about 5% after the firm said Thursday that a phase 2 trial of diranersen in people with early Alzheimer's disease did not meet its primary endpoint.