UPDATE 1-Gilead Sciences quarterly results beat Wall Street estimates

(Adds details of results, analyst comment, byline)

July 26 (Reuters) - Gilead Sciences Inc said on Wednesday its second-quarter profit fell 12 percent as use of its flagship hepatitis C drugs continued to decline, but the results beat Wall Street estimates and the company raised its full-year sales outlook.

Shares of Gilead, which closed at $74.19 on Nasdaq, rose 1.7 percent to $75.44 after hours.

After one-time items, Gilead earned $2.56 a share. Wall Street analysts, on average, had forecast adjusted earnings of $2.15 a share, according to Thomson Reuters I/B/E/S.

"People had a sense they were going to beat on the HCV (hepatitis C) side and that's where most of it came from," said Leerink analyst Geoffrey Porges. Still, with a competing drug from AbbVie Inc likely to be approved by regulators next month, the sales trend is unlikely to maintain the current rate, he said.

Quarterly sales of hepatitis C drugs Sovaldi, Harvoni and Epclusa totaled $2.9 billion, down from $4 billion a year earlier. Analysts had forecast $2.23 billion.

Gilead warned earlier this year that sales of the high-priced drugs were declining due to a combination of fewer patients being deemed eligible for treatment and growing competition from other drugmakers.

Sales of other antiviral products, including Gilead's other main franchise of HIV drugs, rose to $3.6 billion from $3.1 billion for the same period in 2016.

Gilead raised its full-year 2017 product sales estimate to between $24 billion and $25.5 billion, up from a previous range of $22.5 billion to $24.5 billion.

The company's first-quarter net income fell to $3.1 billion from $3.5 billion a year earlier. Overall revenue fell to $7.14 billion from $7.78 billion. (Reporting by Deena Beasley; Editing by Richard Chang)