By Kim Coghill

Washington Editor

Atrix Laboratories Inc. said it successfully completed Phase III trials of Leuprogel 1-month 7.5 mg for the treatment of advanced prostate cancer and expects to file a new drug application early next year.

In the study, the once-a-month Leuprogel treatment suppressed serum testosterone to therapeutically desired levels without testosterone breakthrough, the company said.

Danette Meyer, director of investment relations for Fort Collins, Colo.-based Atrix, said the study exceeded the company's expectations because "we got very low testosterone levels and the lower the testosterone level, the lower the incidence of growth, we hope."

Mean testosterone levels for Leuprogel 1-month were below the National Comprehensive Cancer Network recommendations and the FDA's required level for chemical castration, Atrix said. Mean PSA levels also were decreased to low single-digit levels in the study and no serious treatment-related adverse events were recorded.

The 90-day trial was an open-label, multicenter study of 117 patients.

The Leuprogel 1-month formulation, based on Atrix's proprietary Atrigel drug delivery system, is injected into the body subcutaneously as a liquid, where it solidifies and releases a predetermined systemic dose of leuprolide continuously as it is bioabsorbed. Atrigel is a biodegradable system for local or systemic delivery of drugs.

Atrix also has finished enrollment for the 110-patient, multicenter Phase III Leuprogel 3-month 22.5 mg study, and Meyer said Phase III studies should be complete by the end of the second quarter of 2001. Subsequently, the NDA is expected to be filed in the third quarter.

Meanwhile, enrollment for Leuprogel 4-month 30 mg is expected to begin early next year.

Meyer said the difference in the products is the length of time that Leuprogel is released. "This is how urologists normally treat patients," she said. "They will start a patient off on a 30-day course to see how well they react to it, and make sure they tolerate any side effects - then they will go to the longer treatment."

The company has other products, including Atridox, a dental product used to treat periodontal disease. The product combines Atrigel delivery system with an antibiotic, doxycycline, to destroy bacteria over a period of about seven days.

In late October, Atrix signed a collaborative agreement with Geneva Pharmaceuticals Inc., of Denver, to develop and manufacture prescription generic dermatology products during the next 10 years. The company also has an agreement with Pfizer Inc., of New York, granting Pfizer worldwide licensing and research rights to newly developed products utilizing Atrix's proprietary parenteral, transmucosal and topical drug delivery systems.

Also in October, Atrix entered an agreement with Elan Pharmaceuticals, of San Francisco, to develop fentanyl using Atrix's bioerodible mucoadhesive system for breakthrough cancer pain and management of chronic pain.

Atrix's stock (NASDAQ:ATRX) closed Tuesday at $17.06, up 25 cents.