By Karen Young

IntraBiotics Pharmaceuticals Inc. began enrollment in the third and final pivotal Phase III trial of its iseganan antibiotic to prevent and treat oral mucositis in chemotherapy patients.

The trial follows a similar Phase III study that failed earlier this year due to an error by a third-party vendor. A dosing error by the vendor spoiled data on 102 patients in the 323-patient study, IntraBiotics said. Although the trial missed its primary endpoint of reducing ulceration, it hit on its secondary endpoint of reducing pain. (See BioWorld Today, April 27, 2001.)

With the new trial, IntraBiotics plans to enroll about 500 patients in a randomized, double-blind, placebo-controlled study at about 30 cancer centers in the U.S. The trial will be conducted in high-dose chemotherapy patients undergoing either high-dose myeloablative chemotherapy with a bone marrow or peripheral blood stem cell transplant or patients receiving such chemotherapy for leukemia.

¿We have enrolled two patients as of Tuesday,¿ said Gary Titus, director of investor relations for Mountain View, Calif.-based IntraBiotics.

Titus said the trial entails six daily doses for 21 days, which corresponds to the time at which chemotherapy is administered, Titus said.

The primary endpoint for this trial has changed from the original Phase III trial.

¿We¿re using a severity scale for this trial,¿ Titus said. ¿In the first trial, it was ulceration or no ulceration. We felt that this was not the way to determine the efficacy of the drug, so we¿re looking at it a little bit differently.¿

The goal is to reduce disease severity, and IntraBiotics and its steering committee have designed the trial to have statistical power of greater than 85 percent of hitting the endpoint.

In June, IntraBiotics cut its staff by 70 percent, or about 90 people, consolidated its facilities and terminated certain collaborations to save around $7 million to $8 million per quarter. All of these actions were taken so it could focus full force on the completion of iseganan trials. (See BioWorld Today, June 1, 2001.)

IntraBiotics also is conducting a Phase III trial of iseganan oral rinse in patients undergoing radiotherapy for head and neck cancers, making them likely to suffer from oral mucositis. The company expects to conclude enrollment in this trial by year¿s end and to present results in the second quarter of 2002.

Titus said the company also is encouraged about iseganan for ventilator-associated pneumonia, which is in Phase II trials.

¿If we are able to obtain funding, we would like to begin a Phase III trial next year,¿ he said.

IntraBiotics also has ramoplanin topical for Staphylococcal infections in Phase II trials, studies that earlier this year were delayed a year or more due to enrollment problems and other issues associated with the disease. (See BioWorld Today, March 13, 2001.)

IntraBiotics¿ stock (NASDAQ:IBPI) fell 6 cents Wednesday to close at $1.35.