Shares of Gilead Sciences ( GILD) continued to rise Thursday after the company announced that second-quarter profits rose from a year ago, driven by strong sales of its HIV treatment, Viread. After the end of trading on Thursday, Gilead announced second-quarter net income of $111.5 million, or 49 cents a share, up 11% from the $100.4 million, or 46 cents a share, it had a year ago. Analysts expected the company to earn 35 cents a share in the second quarter. Shares closed up $1.25, or 2.2%, to $59.50 and continued to rise, adding another $2.39, or 4%, to $61.89 after hours. Excluding a $50.1 million provision for income taxes, the company said it earned $161.5 million, up 53% from last year's $105.6 million. Revenue came in at $319.7 million, up 34% from the year-ago $238.9 million. Gilead posted product sales of $299.3 million, up 30% year-over-year, driven by record sales of its HIV-fighter Viread, which came in at $197 million, up 18% from last year. The company said currency effects boosted sales of Viread by $5.8 million. Sales of its other drugs continued to grow as well. AmBisome sales were $55 million, up 7%, while sales of Hepsera came in at $28 million, more than double year-ago levels. Expenses rose 20.6% in the quarter, coming in at $119.4 million, up from $99 million last year.