WASHINGTON – U.S. health regulators have approved Endo Pharmaceuticals Holding Inc and ProStrakan Group PLC's Fortesta testosterone gel to treat men with low levels of the hormone.
The gel is applied with one finger to each thigh, an application aimed at preventing it from rubbing off onto other people, such as children and women, which has been a concern of the U.S. Food and Drug Administration.
Endo officials would not estimate potential U.S. sales for its gel.
Shares of Endo, which holds U.S. marketing rights to the gel, were up 3.6 percent at $36.51 in after-hours trading. They had closed at $35.22 on the Nasdaq.
Endo's Fortesta aims to treat low testosterone levels, or hypogonadism, that can be associated with erectile dysfunction, osteoporosis and hair loss. Almost 14 million U.S. men have low testosterone levels but of those, just 9 percent are getting treated, it said.
In May 2009, FDA called for strong warnings on such topical products after reported exposure in children following skin contact that could cause enlarged sex organs, premature pubic hair development and aggressive behavior.
"It's important to do what one can to prevent the transfer from one person to another," Ivan Gergel, Endo's executive vice president of research and development, told Reuters. "Anyone using it would have to be very careful."
Other approved testosterone gels include Abbott's Laboratories' AndroGel and Auxilium Pharmaceuticals Inc's Testim, both of which carry a so-called "black box" warning as well as patient cautions to wash hands and clothe the area where the drug was applied.
Unlike those two rivals, which contain 1 percent of the active ingredient, Fortesta contains 2 percent testosterone.
Rival AndroGel, which is applied to the abdomen, is expected to bring in $633 million in worldwide sales in 2010, consensus forecasts show, according to Thomson Reuters data.
Eli Lilly & Co and Acrux Ltd also won FDA approval in November for Axiron, a testosterone solution applied to the armpits. It is expected to see sales of $105 million by 2015, according to Thomson Reuters data.
Endo's Gergel said while there is no data comparing Fortesta to rivals that get applied to other body parts, "It's our belief that there's a potential advantage to applying it to the thigh."