By Randall Osborne

Granted a patent for its angiogenic genes to treat heart disease, Collateral Therapeutics Inc. (CTI) is poised to capitalize on a technology that once seemed all but unworkable.

"Four years ago, delivering genes non-surgically to the heart sounded like something that wasn't feasible," said Christopher Reinhard, chief operating officer and chief financial officer of San Diego-based CTI. "People thought cancer was where gene therapy was most likely to surface as a product."

CTI's lead product, Generx, uses the FGF-4 gene to restore blood flow and heart function in patients with stable exertional angina due to coronary artery disease. The treatment is in Phase I/II trials in six different dosage levels at 10 medical centers.

Unlike a cardiac gene-delivery therapy developed by Rockville, Md.-based GenVec Inc., CTI's Generx is designed for delivery by way of a one-time injection through a catheter in outpatient angioplasty patients.

"GenVec's is a surgical procedure," Reinhard said. "To us, the promise of gene therapy is a better, faster, cheaper way, and if you open the chest up, you still have all the trauma of surgery."

BioBypass, as GenVec's product is known, is a modified, replication-deficient adenoviral vector that injects the vascular endothelial growth factor gene VEGF 121 into cells of heart muscle to promote blood vessel growth around blockages. (See BioWorld Today, Aug. 4, 1998, p. 1.)

Genes delivered by catheter are taken up quickly and abundantly, Reinhard said. "The heart is like a sponge," he added. "We know it is very responsive to growth factors."

Schering Deal Keeps Burn Rate Down

Formed in 1995, CTI partnered with Schering AG, of Berlin, in May 1996 to develop the angiogenesis gene therapy technology, licensed from the Regents of the University of California, in Oakland.

"We were able to put together a strong relationship with Schering," Reinhard said, a relationship that meant no reliance by CTI on venture capital and kept its burn rate at less than $1.8 million per year.

"Thirty-seven months from the day we started the company, we had this product in [trials with] people," Reinhard said.

Another CTI gene therapy program covers heart muscle regeneration as a treatment for heart attack, and the company's collaboration with Targeted Genetics Corp., of Seattle, is testing a recombinant adeno-associated viral vector for delivering the adenylycyclase gene to treat congestive heart failure.

CTI's stock (NASDAQ:CLTX) closed Tuesday at $5.875, down $0.125. *