UPDATE 2-Mexico watchdog finds big pharma faces no competition on some drugs

(Adds Janssen no comment)

MEXICO CITY, Aug 9 (Reuters) - Major drugmakers including GlaxoSmithKline Plc, Pfizer Inc and Sanofi SA use legal ways to stifle competition in Mexico from generics that are readily available elsewhere, a senior Mexican antitrust official said on Wednesday.

The companies have done nothing illegal, Juan Manuel Espino, Cofece's director of economic studies, said at a presentation of the body's probe into the Mexican drugs market, which found regulatory failings contributed to a lack of competition.

The report, released by Cofece on Wednesday, found that pharmaceutical firms use legal strategies to extend drug exclusivity after patents expire.

According to a document seen by Reuters, Cofece also identified other pharmaceutical companies, including AstraZeneca Plc, Merck & Co Inc, Novartis AG, Janssen-Cilag SA, Abbott Laboratories, Roche Holdings AG and Eli Lilly and Co.

Resolving the situation could save Mexican consumers 2.5 billion pesos ($139 million) a year, Cofece said.

"The cost of medicines for Mexican families is onerous," Cofece President Alejandra Palacios said at the event in Mexico City.

A Janssen-Cilag SA spokesperson declined to comment until the company had a chance to read the report. None of the other firms identified by Cofece immediately responded to requests for comment.

($1 = 17.9630 Mexican pesos) (Additional reporting by Gabriel Stargardter; Editing by Chizu Nomiyama and Richard Chang)