Pfizer Gives Up Testing Viagra on Women

Women, the maker of Viagra has found, are a lot more complicated than men.

After eight years of work and tests involving 3,000 women, Pfizer Inc. announced yesterday that it was abandoning its effort to prove that the impotence drug Viagra improves sexual function in women. The problem, Pfizer researchers found, is that men and women have a fundamentally different relationship between arousal and desire.

For men, arousal almost always leads to desire. So by improving a man's ability to have erections, Viagra measurably affects his sexual function. But arousal and desire are often disconnected in women, the researchers found, to their consternation.

Although Viagra can indeed create the outward signs of arousal in many women, that seems to have little effect on a woman's willingness, or desire, to have sex, the researchers said.

"There's a disconnect in many women between genital changes and mental changes," said Mitra Boolel, leader of Pfizer's sex research team. "This disconnect does not exist in men. Men consistently get erections in the presence of naked women and want to have sex. With women, things depend on a myriad of factors."

Dr. Boolel said that he and his team were continuing their research. But he said the researchers were changing their focus from a woman's genitals to her head. The brain is the crucial sexual organ in women, he said.

Drugs that affect brain chemistry "could be an extremely interesting area of investigation," he said.

NYTimes