Inex Pharmaceuticals Corp. began the registration process for Onco TCS, its lead product for relapsed, aggressive non-Hodgkin's lymphoma (NHL).

The Vancouver, British Columbia-based company said it began a rolling submission by supplying the first of three major sections of its new drug application to the FDA seeking marketing approval for the product, which is made of the off-patent cancer drug vincristine encapsulated in Inex's TCS (liposomal) drug delivery technology. The TCS technology is designed to provide longer blood circulation, tumor accumulation and extended drug release at the cancer site, potentially increasing the encapsulated drug's effectiveness and reducing its side effects.

Upon disclosing pivotal Phase II/III data in June, the company reiterated prior guidance in forecasting an NDA filing late in the third quarter or early in the fourth. The results showed an overall response rate near 25 percent, including seven patients whose tumors were completely eliminated and 23 whose tumor volume was reduced by more than 50 percent. Another 31 had their disease stabilized while undergoing treatment. (See BioWorld Today, June 26, 2003.)

At the same time, Inex said it was in discussions with several potential partners for the product.

Early results from the studies, reported six months prior, showed an overall response rate of 24 percent. Inex soon after regained full ownership rights to the drug from Dublin, Ireland-based Elan Corp. plc, which said it was no longer focusing on oncology. (See BioWorld Today, Dec. 4, 2002; Aug. 12, 2002; and April 4, 2003.)

Inex said it expects to submit the remaining sections of its application by the end of the year, after which it expects an FDA response within six months, subject to acceptance of the full NDA for review.

The company also is studying the drug in leukemia, lung cancer and lymphoma. Inex's pipeline also features the cancer drugs topotecan TCS and vinorelbine TCS in preclinical development.

On Tuesday, the company's shares (TSX:IEX) gained C8 cents to close at C6.25 (US$4.63).