The U.S. Food and Drug Administration said it approved the drug, a protease inhibitor that blocks a protein needed by the virus to replicate.
The Johnson & Johnson drug, named Olysio, is designed to eliminate hepatitis C, the most common form of the liver-destroying virus. It is a daily pill taken in combination with the long-established drug cocktail used to treat the most common form of the virus.
The FDA's decision comes less than a month after an FDA advisory panel voted unanimously in favor of approving the treatment.
Olysio is the third FDA-approved protease inhibitor for treatment of hepatitis C, the FDA said.
More than 3 million people in the U.S. have hepatitis C, a blood-borne disease that is blamed for 15,000 deaths a year.
Johnson & Johnson is one of a half-dozen companies working to develop more effective treatments for the virus as it threatens to become a major health epidemic among baby boomers and middle-age Americans.
People born between 1945 and 1965 are five times more likely to have the virus than people of other age groups. Many of them contracted the virus by sharing needles or having sex with an infected person in their youth. The disease was also spread by blood transfusions before 1992, when blood banks began testing for the virus.
For the last 20 years, the standard treatment for hepatitis C has involved a grueling one-year regimen of pills and injections. These two antiviral drugs, known as ribavirin and interferon-alpha, cause flu-like side effects including nausea, diarrhea and muscle achiness. The introduction of new drugs from Merck and Vertex Pharmaceuticals in 2011 helped shorten the treatment period and boost cure rates as high as 75 percent.
Olysio appears to be slightly more effective than the standard of care, curing 80 percent of patients who had not previously been treated for the disease, according to studies submitted to the FDA.
More significantly, the drug helped most patients cut the amount of time they had to take the traditional drug cocktail, with its unpleasant side effects, to six months rather than one year.
Additionally, members of the FDA's advisory panel said the drug's once-a-day dosage should be far more manageable for patients than the current drugs from Merck and Vertex, which require taking 12 pills or six pills a day, respectively.