AlphaRx Inc (MARKHAM, Ontario, Canada), an emerging drug delivery company, and Proprius Pharmaceuticals (SAN DIEGO, California), a specialty pharmaceutical and diagnostic services company that focuses on the area of rheumatology and autoimmune diseases, announced that results from the Indaflexâ„¢ 2.5% Topical Indomethacin Cream exploratory phase II clinical trial for osteoarthritis (OA) of the knee (INDF-200) did not achieve its primary endpoints. The proof-of-concept study was initiated in September 2005 by AlphaRx and was performed in Canada. The companies plan to discuss study findings with the US FDA and to advance Indaflex to registration trials.

The randomized double-blind placebo- and vehicle-controlled trial, which included a 6-week treatment period, was conducted in 233 patients with OA of the knee. The primary endpoints were the change from baseline to week 6 in the global Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score and the subject's global assessment of efficacy. Although the trial did not meet its primary endpoints, subgroup analyses of patients with moderate-to-severe pain and more impaired physical function at baseline showed positive trends when treated with Indaflex, compared with patients treated with either placebo or vehicle. Indaflex was demonstrated to be safe and well tolerated.

Indaflex is a topical NSAID (nonsteroidal anti-inflammatory drug) formulation in clinical development for the reduction of signs and symptoms associated with OA of the knee. The active ingredient in Indaflex, indomethacin, has a longstanding and proven clinical treatment record. Delivered through the skin using AlphaRx's nanoparticle technology, the companies believe Indaflex will have an attractive efficacy, safety, and tolerability profile in comparison with oral nonselective NSAIDs or COX-2 selective inhibitors for the treatment of OA of the knee, as well as other diseases and disorders associated with localized pain and inflammation. Indaflex was shown to be superior to other topical preparations and to oral indomethacin in a nonclinical study. In addition, phase I study data on Indaflex showed negligible concentrations of circulating indomethacin when applied to human volunteers, suggesting a very low probability of systemic adverse events, such as gastrointestinal or cardiovascular complications.

Proprius acquired the exclusive global rights, except for Asia and Mexico, to Indaflex from AlphaRx in April 2006. Under the terms of the agreement, AlphaRx received an up-front payment of $1 million and will be eligible to receive additional milestone payments of up to $116 million for the successful development and commercialization of Indaflex, as well as double-digit royalties on worldwide sales. In addition, Proprius has assumed the clinical development costs.

—A. Techman

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