UPDATE 1-U.S. FDA approves AbbVie all-oral hepatitis C treatment

(Adds no price available yet, details on hepatitis c)

Dec 19 (Reuters) - U.S. health regulators on Friday approved AbbVie's all-oral treatment for hepatitis C, providing the first competition for Gilead Sciences huge selling and expensive medicine for the liver-destroying virus.

The AbbVie regimen consists of four different anti-viral drugs to be taken as three pills in the morning and one in the evening. The U.S. Food and Drug Administration approved the regimen, which will be sold under the brand name Viekira Pak, for patients with genotype 1 form of the virus, the most common type of hepatitis C and the most difficult to treat.

Gilead's Sovaldi, which was approved a year ago, had been selling at the rate of about $3 billion per quarter due to huge pent up demand. Sovaldi is now combined with another Gilead drug and sold as Harvoni, which is taken as one pill once a day for 12 weeks at a cost of about $94,500. Some patients can take it for just eight weeks, which costs about $63,000.