BioWorld International Correspondent

LONDON - Ark Therapeutics plc got the go-ahead from U.S. and European regulators to move Vitor, its treatment for cancer cachexia, into Phase III, meaning the company now boasts three products in the final stages of development.

Both regulators said existing Phase II/III data from a trial completed in 2006 are sufficient to proceed, and with fast-track status from the FDA, the London-based company expects to start the trial in the second half of 2007. There is a choice of going for approval based either on Vitor's ability to restrict weight loss, or to improve functional measurements such as muscle loss.

CEO Nigel Parker said the outcome of the latest meetings with regulators represented more good news for the company. "We now have three products at the Phase III development stage, which gives us one of the strongest late-stage pipelines in the small cap biotechnology sector."

Sam Fazeli, senior analyst at Piper Jaffray in London, said in a research note he had been concerned that Ark would be asked to conduct another Phase II, "so this is positive news."

The Phase III study will involve up to 250 patients to assess the safety and efficacy of Vitor in non-small-cell lung cancer patients. The first four weeks will be a lead in to confirm weight loss is occurring, after which subjects will be randomized into the study. The U.S. and European study is expected to take 18 months to complete.

The earlier Phase II/III study was first in man in cachexia, but Vitor, an orally administered angiotensin converting enzyme (ACE) inhibitor, is marketed in Japan and certain countries in Europe as a treatment for hypertension. Ark in-licensed it from the Japanese pharmaceutical company Tanabe for development in cachexia, based on insights into the role of the renin-angiotensin system in controlling the ability of mitochondria to generate energy.

Cancer cachexia is caused when cytokines are released that interfere with energy production by mitochondria. Ark discovered that the subsequent breakdown of actin and myosin in muscle cells is mediated by angiotensin II.

In the Phase II/III study Vitor significantly reduced the rate of cachexia in patients with non-small-cell lung and colorectal cancer, but not in pancreatic cancer. In the combined analysis treated patients on average lost 29 percent less weight, but because of the results in pancreatic cancer the difference did not reach significance.

Vitor now joins Ark's two other products in Phase III - Cerepro, a gene therapy treatment for brain cancer and Trinam, a locally-delivered gene therapy for preserving the access grafts of kidney dialysis patients. "Only one of these products needs to make it for Ark to join the ranks of successful biotech companies," said Fazeli.