Roberts' propiram betters tramadol in Phase III

Roberts Pharmaceutical may have a gem tucked away in its productpipeline, if new data from a Phase III trial are borne out by further study. Preliminary results from the study show that Dirame (propiram), an orally-administered mu opioid receptor agonist/antagonist, achieved superior dental pain control to Johnson & Johnson's $350 million-product Ultram (tramadol).

The study involved 350 patients who had two or more molars extracted, and compared four doses of propiram (25mg, 50mg, 100mg and 150mg) with the maximum recommended dose of tramadol (100mg), as well as placebo. Propiram was significantly more effective than placebo in reducing pain intensity at doses above 50mg but, more importantly, also outperformed the mainstay opioid agonist tramadol.

Propiram has had a long and convoluted route through to development, having originally been discovered in the 1970s by Bayer. It was taken right through to the registration stage by Bayer and partner Schering-Plough in their ill-fated joint venture in the mid-1980s, but once this was dissolved the rights transferred to S-P, which considered propiram maverick to the rest of its portfolio and killed the project, even though approvals had been granted in some European countries. Roberts acquired the product in the late-1980s, but it languished in the pipeline until a review a couple of years ago drew attention to its potential in the $3.5 billion US opioid analgesia market.