BioWorld International Correspondent

Pharmexa A/S received regulatory approvals in four countries for a pivotal Phase III trial of its peptide-based cancer vaccine, GV1001. The first patients will be recruited in the coming months, CEO Jakob Schmidt told BioWorld International. Over the next couple of years, the trial aims to recruit 520 patients through 60 cancer centers located in 10 European countries and Australia.

"We would expect the results by the end of the decade - that's our goal," Schmidt said.

The study, called PrimoVax, will investigate the efficacy of GV1001 in pancreatic cancer. Trial participants will be assigned randomly to either one of two treatment arms. Half will receive gemcitabine chemotherapy, the current standard treatment for inoperable pancreatic cancer, while the other half will receive GV1001 followed by gemcitabine if or when their cancer progresses. The primary endpoint of the study will be survival, while time to progression will be measured as a secondary endpoint. In a Phase I/II trial of GV1001, 38 evaluable patients in receipt of the vaccine had a median survival time of 8.6 months, vs. about five to six months for current treatment, according to a recent Pharmexa investor presentation.

A second Phase III study of the therapeutic, called TeloVax, also is due to get under way this year. TeloVax, an investigator-sponsored trial funded by the London-based charity Cancer Research UK, will recruit 1,110 pancreatic cancer patients who will receive either gemcitabine alone, gemcitabine in combination with GV1001 or gemcitabine followed by gemcitabine.

Hørsholm, Denmark-based Pharmexa obtained GV1001 when it acquired Oslo, Norway-based GemVax AS in a stock deal then valued at about DKK40 million (US$7 million). The vaccine is based on an immunogenic 16mer peptide, containing both CD4 and CD8 epitopes. It is derived from the telomerase enzyme, which is over-expressed in a variety of cancer cells. (See BioWorld International, April 13, 2005.)

The program is wholly owned by Pharmexa, but Schmidt said the company might be open to entering a partnership.

"If we decide to partner this, it is because we are convinced that a partner could help us to pursue the many other applications of this drug," he said. A Phase II trial of GV1001 in liver cancer is due to commence later this year. However, the company might market the drug itself in its lead indication, he added.

"A lot of cancer doctors in this space will get to know this drug. That could be a starting point for later marketing," he said.

Pharmexa recently received attention from Geron Corp., of Menlo Park, Calif., which issued a press release Feb. 2, setting out its proprietary claims to telomerase-based vaccines. The companies have been engaged in patent opposition proceedings in Europe.

"There are these very standard opposition proceedings going on. They will take several years from now to resolve," Schmidt said. "We are confident we will prevail in both."