By Mary Welch

Vivus Inc. said it will submit a new drug application (NDA) within the next several weeks for Alibra, its second-generation treatment for erectile dysfunction.

"We haven't released a lot of information about Alibra but we have just completed our Phase III trial and expect to file the NDA this fall," said Terry Nida, vice president of worldwide sales, marketing, licensing and corporate development. "Alibra overcomes all the difficulties of MUSE, which is our best-selling treatment of erectile dysfunction."

MUSE is a non-injectable delivery system for alprostadil, which is chemically identical to the naturally occurring eicosanoid, prostaglandin E1 (PGE1). Prior to sex a man inserts a small tip applicator into the urethra and gently pushes a button on top of the applicator, releasing an effective dose of alprostadil directly to the urethral mucosa.

"It's like a suppository, except its inserted into the penis," Nida said.

Alibra is a mixture of alprostadil and praxosin, an alpha blocker with a high safety profile.

"Thirty percent of American men reported some pain when using MUSE but only 6 percent of European men did," Nida said. 'We think it's because American doctors asked about pain in particular while European doctors didn't. Of course, European men reported that the difference was that American men were wimps. However, we have redesigned the dose to further eliminate any side effects. Few Americans stopped using MUSE because of the pain."

Another difference between Alibra and MUSE is that Alibra will come in one single dose rather than the four dose options available with MUSE.

"A doctor prescribing MUSE to a patient must start a trial-and-error process to see which dosage is the most effective," Nida said. "We've found that at the 125 mcg dose, only between 5 percent to 10 percent of the men had successful erections and about 25 percent had erections at 250 mcg. But at the 500 mcg or 1,000 mcg dose, there was a 50 percent success rate."

Until New York-based Pfizer Inc.'s Viagra hit the market, MUSE was a leading treatment for erectile dysfunction. MUSE was the 13th most successful launch and reported 1997 sales of $130 million - the first year it was on the market, Nida said.

"We had back orders of five months when it first became available. It was the No. 1 treatment and then Viagra came and we got killed. We lost 80 percent of our business to Viagra," he said. "Men would rather pop a pill and started believing that Viagra was the cure for death. But the safety profile is disturbing."

Nida said Viagra isn't as effective with men who are organically dysfunctional, such as those who are diabetic or had prostate surgery. "We figure we have a real opportunity with Alibra to pick up all the Viagra failures."

Alibra will continue to have MUSE's ease of delivery, Nida said. A doctor instructs the man how to insert the application tip and activate the drug. Eighty percent of the drug is absorbed within three minutes and it takes about 10 minutes for a man to get an erection that will last anywhere from 30 minutes to an hour, he said.

"So for 10 minutes you have to sort of walk around and let the drug absorb - clinically speaking," said Nida. "Our partner has told us that in Sweden, that 10 minutes is considered foreplay. The Swedish couple will insert the drug, massage the penis. In America, the man walks around in the bathroom while his wife waits in bed."

As the population ages, Nida said Mountain View, Calif.-based Vivus will be well prepared to attend to accompanying sexual problems. In addition to Alibra, the company has a male premature ejaculation product that should begin Phase II trials this year and a female sexual dysfunction product slated to enter trials next year.

"It'll happen to all men," Nida said. "You don't get the erections you had in your 20s. You don't realize it's happening over time but it is. It's like your eyesight. It slowly goes but you don't really notice it. Then someone gives you a pair of glasses and you go, 'Whoa!'"

Vivus is "actively" seeking a corporate partner for Alibra. MUSE is partnered with AstraZeneca plc in Europe and Johnson & Johnson everywhere else except Japan and the U.S. The company is in discussions with potential partners in those countries. n