BioWorld International Correspondent

LONDON - Ark Therapeutics Group plc is ahead in the race to be first with an approved gene therapy product outside China, after Cerepro, for treating glioma, was accepted for review in Europe.

The news followed approval a week earlier for the company's facility in Finland to manufacture the product for commercial supply, and the release of positive Phase IIb data for a second gene therapy product, Trinam, in preventing vascular access grafts blocking in kidney dialysis patients.

Nigel Parker, CEO, told BioWorld International: "We're delighted really. If you had asked us four years ago when you look at all the money going into this field in the U.S. if Ark would be the first, we would not have thought it likely."

Ark's filing on Cerepro, containing data from a Phase I safety study and two Phase II studies, was filed under an "exceptional approval" route. Parker said that would not expedite the review process, which he expects to take 10 to 14 months, but allowed the company to file before completing a large-scale corroborative study. The expectation is that approval will be received by the end of 2006.

The corroborative study now has begun, and will recruit around 250 patients in 40 centers in Europe. Half will receive standard care, and half standard care plus Cerepro. The product has Orphan Drug status in Europe and the U.S. Parker said the company will discuss Cerepro with the FDA "in due course."

At the same time, the London-based company announced positive preliminary results in a Phase III study of Vitor in the treatment of cancer cachexia.

"This has been a tremendous two weeks at Ark," Parker said. "The company ends an intense period of news-flow in exceptional shape."

Erling Refsum, analyst at Nomura in London, concurred. "These are all major valuation-changing events. They increase the chances of Cerepro [and] Vitor reaching the market."

Cerepro uses an adenovirus to deliver the gene for the enzyme thymidine kinase, which converts the prodrug ganciclovir into a form that is cytotoxic to dividing cells. The product is injected into healthy tissue after surgery to remove a tumor, and subsequently ganciclovir is administered intravenously. Unlike tumor cells, healthy neurones are not dividing, and thus are unaffected.

In the Phase IIb trial of Cerepro involving 36 patients, there was an 81 percent increase in mean survival time from 39 weeks to 71 weeks, compared to standard care. Taken with the robust safety data, that raises the question of whether it is ethical not to administer Cerepro to all patients in the corroborative trial.

Parker said the protocol for the corroborative study was determined by the regulators, but noted that similar "non-interventional" gene therapy products (where the gene is not integrated in the genome) have been in more than 600 trials. "The safety database is now huge, and I do think the regulators are getting more relaxed," he said.

Overall, gene therapy is showing clinical benefits with good safety profiles in hitherto difficult to treat diseases, Parker said. "I think the world must start to understand that gene therapy has come of age. Getting the [Cerepro] file accepted for review is a hell of an announcement."