Trimeris (Nasdaq: TRMS) and Roche took the next step in bringing their new AIDS drug Fuzeon to market by filing a new drug application with the Federal Drug Administration on Tuesday.

Fuzeon, formerly known as T-20, is the frontrunner in a new class of anti-HIV drugs called “fusion inhibitors,” developed for the treatment of HIV-1 infection in combination with other antiretroviral agents. Roche and Trimeris have requested priority review status from the FDA, which if granted would enable Fuzeon to be reviewed within six months.

Robin Fastenau, a spokesperson for Trimeris, says the Durham-based company is in a “quiet period”, and no further comment would be made beyond those included in a press release. Fastenau referred all inquiries to Roche.

The announcement included additional good news for the two firms.

Roche, based in Nutley, NJ, confirmed the successful completion of the next major manufacturing milestone at its Colorado manufacturing facility … validation of the first three commercial batches of active ingredient for Fuzeon. Some concern haad been raised as to whether the plant could meet demand for Fuzeon.

Roche and Trimeris say they also plan to file for Fuzeon approval in Europe before the end of September.

The announcements sent shares of TRMS as high as $47.65 for the day before closing at $46.18. That was still 35 cents more than the previous day’s close.

Fuzeon, unlike existing anti-HIV drugs that work inside the cell, has a unique mode of action that is designed to block HIV from entering the human immune cell, Trimeris says. Consequently, Fuzeon is active against HIV that is resistant to the currently available classes of anti-HIV drugs.

The regulatory submissions for Fuzeon are based on 24-week data from two large, international Phase III trials, which Trimeris says indicate that patients on Fuzeon plus an individualized background regimen of other antiretroviral drugs were twice as likely to achieve undetectable levels of HIV in the blood as compared to patients who received an individualized background regimen alone. Fuzeon also provided a significant increase in immune cells at 24 weeks.

“Fuzeon was designed from the outset to block HIV replication in a completely different manner than current antiretroviral drugs, while not substantially adding to the toxicity of other agents,” Dani Bolognesi, chief executive officer of Trimeris, said in a statement. “Fuzeon’s unique mode of action is designed to block HIV before entering the human cell and if approved, it will represent the first of a new class of anti-HIV drug in seven years.”