The drug business is good, even forinvestors. (Photo: Getty)

(Bloomberg) –A boom in major U.S. pharmaceutical stocks iscreating a swarm of activity around an exchange-traded fundtracking the massive drugmakers.

The $8.2 billion Vanguard Health Care ETF, known by its tickerVHT, had 1.6 million shares worth $272 million trade Monday, recordone-day turnover for the fund. It also hasn't seen a day ofoutflows in August, with $145 million of net inflows putting theETF on track for its best month since June 2017.

U.S. drugmakers are hot, with Pfizer Inc., Eli Lilly & Co.and Merck & Co. soaring to 16-year highs after reportingstronger than expected second-quarter results and the S&P 500Index pharmaceuticals industry group hitting an all-time highMonday. Together, Pfizer and Merck make up more than 10 percent ofthe fund's exposure. Its largest holding is industry bellwetherJohnson & Johnson, which is heading for its best four-day runsince early 2016.

A smaller health-care fund, BlackRock Inc.'s $850 millioniShares U.S. Healthcare Providers ETF, or IHF, saw $48 million ofinflows Monday, the most in almost two months. Trading volume inthe fund hit $54 million Monday, more than eight times its averageover the past year.

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