By Mary Welch

Valentis Inc. said interim Phase II data showed evidence of blood vessel formation when a non-viral vascular endothelial growth factor (VEGF 165) gene medicine was delivered via its cationic lipid gene delivery system.

"The vector works," said Bennet Weintraub, chief financial officer of the Burlingame, Calif., company. "Not only does it work but there are no adverse side effects."

Valentis presented the results Wednesday at the American Heart Association meeting in Atlanta.

More than 50 patients in Finland with either peripheral vascular disease (PVD) or coronary artery disease have been treated so far with the plasmid-based VEGF 165 therapy. However, the interim results involved only those with PVD.

Patients enrolled in the double-blind, placebo-controlled trial received either a plasmid-based, non-viral VEGF 165 gene medicine, an adenovirus encoding VEGF 165, or a placebo. VEGF 165 is an angiogenic factor, developed by South San Francisco-based Genentech Inc., that has also been shown to inhibit restenosis, or the narrowing of the blood vessels, following angioplasty or stent insertion.

The gene medicine was administered with a catheter to patients with PVD following angioplasty.

The interim results showed there was an increase in the number of blood vessels in both the plasmid and adenovirus groups but not among placebo patients. The trial is expected to last another nine to 12 months.

"It's the first time we've seen a human clinical response using VEGF 165 that is positive and it shows that one of our delivery systems is effective," Weintraub said.

The non-viral system based on Valentis' cationic (positively charged) lipid formulation was as effective as the adenoviral vector, Valentis said. However, the company believes the plasmid-based gene medicine is preferable to the viral vector for chronic indications such as PVD because non-viral gene medicines don't elicit a specific immune response.

"There are problems with the viral vectors because they can cause an immune reaction," Weintraub said. "That's not the case with plasmid-based vectors. You can re-dose with them."

There are two physician-controlled studies being conducted in Finland. The second trial is with patients with coronary artery disease. Both are being conducted by Seppop Yla-Herttuala.

"We don't own VEGF-165; Genentech does in the U.S.," Weintraub said. "But they don't own it in Finland."

Weintraub said that there are two ways the company could market VEGF 165 with its lipid gene delivery system. "Our results could be an incentive for Genentech to do a deal with us," he said. "Or we could replace VEGF 165 with something else. The important thing is that our delivery system is safe."

Valentis' stock (NASDAQ:VLTS) closed Wednesday at $4.375, up 62.5 cents or 17 percent.

In other news from the meeting:

¿ Cell Genesys Inc., of Foster City, Calif., and Mitotix Inc., of Cambridge, Mass., said further preclinical studies of gene therapy with a novel cell cycle inhibitor fusion gene, p27/p16, demonstrated potent inhibition of arterial occlusion associated with restenosis. The studies indicated about a 50 percent reduction in the proliferation of smooth muscle cells following angioplasty in blood vessels compared with untreated control vessels.

¿ Baylor College of Medicine, of Waco, Texas, and the Cleveland Clinic Foundation said bivalirudin, a direct thrombin inhibitor, in combination with a GP IIb/IIIa antagonist in patients undergoing coronary angioplasty, may provide predictable anticoagulation as an alternative to heparin without evidence of clinically significant interactions between bivalirudin and abciximab (ReoPro) in patients receiving abciximab for angioplasty. Bivalirudin is approved for angioplasty patients in New Zealand and is under review in Europe and the U.S. The Medicines Co., of Cambridge, Mass., acquired bivalirudin from Biogen Inc., of Cambridge, Mass.

¿ CV Therapeutics Inc., of Palo Alto, Calif., said it pinpointed a heart disease gene responsible for removing cholesterol from cells. The company also said increasing the amount of this gene, ABC1, in cultured cells in the laboratory resulted in a significant increase in the amount of cholesterol pumped out of these cells.

¿ Pharmacyclics Inc., of Sunnyvale, Calif., said Phase I results of Antrin (motexafin lutetium) injection showed that it was clinically active in patients with peripheral arterial disease. Fifty-one patients were involved in the trial. The company now is conducting a multi-center, controlled, randomized Phase II trial in patients with peripheral arterial disease, evaluating Antrin photangioplasty for atherosclerosis and for prevention of restenosis after balloon angioplasty.