The iShares Global Healthcare ETF (IXJ) is seeing unusually high volume in afternoon trading Monday, with over 290,000 shares traded versus three month average volume of about 31,000. Shares of IXJ were off about 0.9% on the day.

Components of that ETF with the highest volume on Monday were Pfizer (PFE), trading off about 1% with over 12.1 million shares changing hands so far this session, and Merck (MRK), off about 1.5% on volume of over 4.7 million shares. Align Technology (ALGN) is the component faring the best Monday, up by about 1.9% on the day, while Biogen (BIIB) is lagging other components of the iShares Global Healthcare ETF, trading lower by about 5.6%.