FOSTER CITY, Calif. (AP) — Gilead Sciences has acquired about 95 percent of the outstanding shares in Pharmasset as it draws closer to closing its $11 billion deal for the drug developer.

Gilead, based in Foster City, Calif., said about 72 million Pharmasset shares have been tendered. Gilead announced in November that it would pay $137 per share in cash for the, a Princeton, N.J. drug developer.

Pharmasset Inc. has three potential hepatitis C treatments in clinical testing, including a candidate labeled PSI-7977 in late-stage testing. Analysts see promise in the drug because doctors may be able prescribe the pill in a combination with other treatments that does not involve interferon, an injection that comes with rough side effects.

Hepatitis C is a virus that can lead to life-threatening liver damage and is the main cause of liver transplants in the United States. Analysts expect it to become a bigger health problem as baby boomers ages.

Gilead Sciences Inc. plans to buy additional shares of Pharmasset directly from the company, which has no drugs on the market. The acquisition is expected to close in the first quarter.