* What: Q1 results
* When: Monday, May 11
* Q1 expected to top estimates
* Doryx sales to drive results
* Oral contraceptives sales to slow down
By Vidya L Nathan
BANGALORE, May 8 (Reuters) - Higher sales of Doryx, an acne product, are expected to push specialty pharmaceutical company Warner Chilcott Ltd's WCRX.O first-quarter results above market expectations.
Increasing prescriptions of Doryx will likely more than offset slowing sales of the company's oral contraceptives, such as Loestrin 24 Fe and Ovcon 50, which have been trying to stave off competition from cheaper generics.
"I think Doryx is a source of upside because they have been shifting to the 150 milligram dose, which has a higher value per prescription," Leerink Swann analyst Gary Nachman said.
Roth Capital Partners analyst Scott Henry expects the acne product to generate first-quarter sales of about $44.4 million.
The company, which makes dermatology and women's healthcare products, markets Doryx in 75 mg, 100 mg and 150 mg doses, which together account for about 20 percent of its total revenue.
Nachman expects Doryx to replace Loestrin 24 Fe as Warner Chilcott's key revenue driver in the quarter. He sees sales of Doryx climbing to 25 percent of the company's total sales by the end of the year.
For the first quarter, the consensus view is for the drug maker to earn 39 cents a share, before special items, on revenue of $249.7 million, according to Reuters Estimates.
While generic competition for Doryx's 75 mg and 100 mg doses looms large, analysts see the company retaining most of its franchise on the acne drug.
Some analysts expect the generic versions of the 75 mg and 100 mg doses to hit the market as early as the third quarter.
However, analysts remain confident that Warner Chilcott will be able to defend its patent on the 150 mg dose, which would help maintain the company's top-line growth.
"(Warner Chilcott) has effectively switched almost 80 percent of Doryx users to 150 mg strength. So the 75 mg and the 100 mg franchise, which could go generic any day, is only 20 percent of the (Doryx) business," Roth Capital's Henry said. (Editing by Anne Pallivathuckal)