West Coast Editor

Cellegy Pharmaceuticals Inc.’s stock tumbled more than 50 percent on news that the company is withdrawing the new drug application for Cellegesic, its nitroglycerin ointment for the treatment of pain from anal fissures.

The FDA has refused to approve the drug without more information.

“Our options were to take an unapprovable letter and launch an appeal or to withdraw and work with the system to better understand and obtain agreement on the issues,” said Michael Forrest, chairman, president and CEO of South San Francisco-based Cellegy.

The company’s shares (NASDAQ:CLGY) ended Friday at $2.90, down $3.70, or 56.1 percent.

Forrest spoke to investors in a conference call, saying the company “does not really have a clear understanding” of what the FDA will require, but the agency’s concerns “seem to center around the magnitude of the pain reduction we’ve received vs. headaches that are often present with any nitrate therapy.”

Those headaches “were quite frequent,” as is normally seen with nitrate treatments. About 50 percent of patients developed headaches, but only 5 percent dropped out of the trial.

“We think the protocol, the conduct of the trials and the data we submitted were highly consistent with what we’ve asserted all along,” Forrest said.

As a major buyer of Cellegy stock himself, Forrest added in the conference call, “I can certainly empathize and sympathize with what you’re going through right now.”

Several years ago, Cellegesic (then known as Anogesic) failed to meet its primary endpoint of complete healing of anal fissures in a Phase III study, but showed positive results in the secondary endpoint of pain reduction. The NDA was submitted in June. (See BioWorld Today, Dec. 17, 1999, and June 27, 2001.)

The firm has “always enjoyed very good relations with the FDA, and the reviewer on the product has not changed,” Forrest said, noting that the agency contact who helped Cellegy design the trial has retired, but that didn’t seem to affect anything.

Forrest told BioWorld Today he “really can’t expatiate further,” but the company will be meeting with the FDA and will have more to say in the next few months.

The worst-case scenario, he said, is a new trial, and the best case is some resubmission of the existing data, which likely would take another six months to review. Cellegy has about a year’s worth of cash, Forrest said, even if the firm must conduct another “minor” trial.

Cellegesic’s name was changed in March, at the advice of the FDA and to avoid confusion with already-marketed products. The company’s transdermal testosterone gel, Tostrex, has completed Phase III trials and Forrest said he expects the NDA to be filed in the next two or three months.