GlaxoSmithKline Plc and Bayer AG won US approval on Tuesday to sell impotence drug Levitra, the first rival to the popular Viagra in the world's most profitable drug market. The announcement, from the US Food and Drug Administration, means that Levitra, an orange pill, will give men an alternative to Pfizer Inc.'s famous diamond-shaped blue pill Viagra, the drug that transformed impotence treatment after its 1998 debut as the first oral therapy for the condition.
Viagra gained instant success as the first oral therapy for impotence, but Levitra's makers are aiming to lure many of the millions of men who have not sought treatment. An estimated 30 million US men experience some level of erectile dysfunction.
"We know, from considerable market research, that the market is ready for new options," said Lawson Macartney, head of strategic management of GlaxoSmithKline's cardiovascular, metabolic and urology drugs.
Another competitor, a pill called Cialis, also may hit the US market later this year.
Levitra, Viagra and Cialis all work by blocking an enzyme called PDE-5, which affects blood flow to the penis, but the potency, speed and duration of each drug are hotly disputed.
Levitra's makers say a major plus is that it works quickly. Men taking Levitra can have an erection in 16 minutes, and any time after that, up to five hours later.
Pfizer has responded with studies showing half of men taking Viagra were able to have sex within 20 minutes.
Trials of Cialis, from Eli Lilly and Co. and ICOS Corp., shows it gives patients a window of up to 36 hours in which to have sex. The window is about four hours for most men taking Viagra.
Levitra's most common side effects include headache, flushing and nasal congestion.
The most common side effects from Viagra are headaches, flushing and stomach upset. Bureau Report