Vivus reported positive results from a Phase III study of avanafil for erectile dysfunction, following on the heels of recent positive Phase III data for the company's obesity compound Qnexa.

Both products are headed for back-to-back regulatory filings, with a new drug application slated to be filed this year for Qnexa and late 2010 or early 2011 for avanafil.

"It's amazing to announce Phase III results back to back - Qnexa in September and now this," Vivus CEO Leland Wilson told BioWorld Today. The Phase III data for the obesity and ED compounds, "both knocked the ball out of the park" on safety and on efficacy, he said.

Moving two products through the regulatory process one after the other is a hugely expensive undertaking for a small biotech. But with the Phase III Qnexa studies completed and $227 million in the bank, Vivus looks well funded.

The $227 million is "a nice round number for a small biopharmaceutical company," Wilson said.

Michael King Jr., managing director at Merriman Curhan Ford, stated in a research note, "Two NDA-ready assets make Vivus look all the more attractive to us."

Mountain View, Calif.-based Vivus has said that it plans to secure partners for both products. But after seeing the avanafil data, Wilson said, "It's tempting to want to play a role in selling the product."

As it did with Qnexa, Vivus plans to hold off on any licensing discussions for avanafil until it has all the Phase III data in hand, he said.

There are three remaining Phase III avanafil studies, all of which are relatively small compared to the 694-patient study that was just reported. One of the studies, a one-year long-term safety study, has passed the six-month mark and will report data in the second half of next year. Another will complete enrollment toward the end of this year, and the other is expected to report data in mid-2010.

In the first of four Phase III avanafil studies, the product was shown to work in 30 minutes or less as measured by successful intercourse. Full efficacy was maintained for all doses across multiple time points from 30 minutes to beyond six hours.

It can take 60 minutes with Viagra and two hours with Cialis to reach maximum plasma levels. Though, Cialis' effect can last over a 36-hour period. Avanafil is designed to provide "on-demand" therapy, Wilson said.

In addition to the rapid response, avanafil also was shown to be well tolerated as demonstrated by a high retention rate (85 percent). Study patients had low reports of common side effects with ED drugs that inhibit the enzyme PDE5. "Clearly, there seems to be a differentiation from a safety standpoint, as well," Wilson said. He noted that avanafil is highly specific for the PDE5 enzyme while other isoforms of the enzyme target other parts of the body besides the penis.

Viagra has been associated with a "blue haze" problem in the eye, where PDE6 is found. Patients taking nitrates are restricted from taking drugs like Viagra because of the drug's effect on PDE1, found in the cardiovascular system.

Although avanafil was not studied alongside other ED therapies, the placebo-subtracted basis may provide some sense of relative profile, Wilson explained. For example, he noted that for headaches, avanafil had a lower rate on a placebo-subtracted basis than Viagra, Levitra and Cialis.

And in a separate nitrate interaction study that Vivus conducted in the hospital setting, Viagra had substantially greater ability to lower blood pressure than avanafil in the presence of nitrates.

Wilson said that the company does not expect avanafil to be recommended for use with nitrates, but he said a doctor may prescribe it if there is a potential emergency situation that could arise in which nitrates would need to be used.

Cory Kasimov, an analyst with JMP Securities, said, "There's no question in our mind that these are indeed positive data that reaffirm the drug's differentiating attributes (primarily faster onset of action) relative to other PDE5 inhibitors currently on the market (i.e. Viagra, Cialis and Levitra)."

But Kasimov expressed skepticism about the commercial opportunity for avanafil "given the brand awareness of the entrenched competition," especially with the Viagra patent expiry in 2012.

Like the obesity market, the ED market also is blockbuster opportunity with sales of currently available ED therapies that exceed $3.8 billion a year, according to Vivus.

Shares in Vivus (NASDAQ:VVUS) rose 20 cents to close at $8.77.