Metabolic pain drug meets trial milestones

Melbourne-based Metabolic Pharmaceuticals (ASX:MBP) has received a go-ahead to progress its painkiller ACV1 to the second part of its phase I clinical trial dosing in humans.

Thirty patients in total have been administered with all of the planned single subcutaneous doses of ACV1 escalating in six steps from 5 to 400 micrograms per kg body weight.

Each of the six groups contained four treated patients and one placebo, with a very low single dose or placebo administered first. The blinded data was reviewed by an independent safety monitoring committee, which then approved the progression to the next dose administration. This process continued up to dose number six.

ACV1 is a 16-amino acid peptide, alpha-conotoxin, derived from the venom of the Australian marine cone shell Conus Victoria. The peptide specifically blocks nictonic acetylcholine receptors to provide relief from chronic neuropathic pain.

The safety committee has reviewed the blinded results of the first part of the ACV1 dosing study and approval has been granted by the human research ethics committee to start the multiple dose part of the study.

"Putting a brand new drug into humans is always an interesting experience, so it's very exciting to have got through this first phase of the safety study," said Metabolic's CEO Roland Scollay.

The first patient in the second part of the study will be dosed tomorrow, said Scollay. Dosing will start at 100 micrograms per kg per day for seven days, with the intention of escalating to 200 and finally 400 micrograms per kg per day for seven days, with five patients per dose.

"Once that's complete, then all the formal unblinding will happen and the final detailed analysis of the data. Then we'll be announcing the formal technical outcome well before the end of the year," said Scollay.

Based on the encouraging results of the first part of the trial, and assuming all goes well, Metabolic expects ACV1 to enter phase II human clinical trials in the first half of 2006, he said.

While the phase I study is designed to test safety rather than efficacy, Scollay said that: "The data in animals looked really good, and in particular this drug is interesting because not only does it give acute pain relief but it seems to in some way repair damaged nerves."

Scollay said the neuropathic pain market was underserved, with a projected global market estimated at being worth $US5.5 billion by 2010.