Shares of Gilead Sciences fell 9 percent Friday, dragging down the 's health care sector, after reporting weaker-than-expected quarterly results.
Health care fell more than 1.5 percent and was the biggest laggard within the benchmark index. The S&P was about 0.5 percent lower on Friday.
On Thursday, the pharmaceutical giant posted earnings of $3.03 a share, ex-items, on $7.79 billion in revenue. Analysts expected Gilead to report earnings of about $3.15 a share on $8.12 billion in revenue, according to a consensus estimate from Thomson Reuters.
The company also reiterated its full-year guidance and announced that it is raising its dividend by 9.3 percent to 47 cents a share.
Several analyst firms reduced their price targets on the stock, including Leerink, which cut its target to $123 from $127.
Still, the firm said: "It is worth remembering that every 18 months or so, Gilead lays an egg, so to speak, in quarterly results and typically rallies strongly on more favorable results in the following periods."
The stock closed at $88.21 on Friday afternoon.
Gilead shares are down nearly 13 percent year to date, but have rallied about 8 percent in the past three months.
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