Metaphore Pharmaceuticals Inc reported successful Phase IIa clinical trial results of their lead compound, M40403, a small molecule that mimics the activity of superoxide dismutase, in a model of dental pain designed to validate its potential as a safe and active therapeutic compound.

The clinical trial compared three doses of M40403 (5 mg, 10 mg, and 20 mg via 30 minute intravenous infusion) to placebo in a single dose, randomized, double-blind, placebo-controlled parallel group study in 250 patients with moderate to severe pain following dental extractions. An intravenous bolus dose of 30 mg ketorolac, a powerful non-steroidal anti-inflammatory drug, was used as a positive control.

This concept validation study demonstrated that at peak plasma levels after administration of 20 mg M40403, statistically significant pain relief was achieved compared to placebo (p<0.05). The results also confirmed that M40403 has an acceptable safety profile with no serious adverse events reported, thus validating the potential of the compound as an active therapeutic drug.

Metaphore is also currently conducting a Phase I clinical trial to evaluate the safety, tolerability and pharmacokinetics of M40419, another superoxide dismutase mimetic product candidate, in healthy subjects, and expects to announce data in the third quarter of this year.

Pre-clinical studies of Metaphore's lead product candidates, M40403 and M40419, demonstrated several properties that may make them attractive candidates for the treatment of pain, including evidence of synergistic pain relief with opioids, the apparent ability to reverse or prevent tolerance to the analgesic effects of opioids, and lack of sedating side effects.

The medical community recognizes a growing need for new stable, non-narcotic pain therapeutics that can reduce pain, both chronic and acute, without efficacy limits or significant side effects. Metaphore's proprietary superoxide dismutase mimetics have demonstrated utility in a variety of in vivo pain models, including acute post-surgical pain, dental pain, and chronic neuropathic pain, where current treatments have significant limitations.