Staff Writer

At first glance, any correlation between biotechnology and auto parts would likely go unnoticed. But such an indirect relationship is integral to GTx Inc., a five-year-old company developing products primarily to treat men's health disorders, in large part with funding from an auto parts scion.

Working in the shadows for much of its existence, the Memphis, Tenn.-based company has developed a robust pipeline that includes two programs that have entered clinical trials as well as a virus-based technology program. The latter is the subject of GTx's first deal: It is teaming with Wyeth in an effort to further develop its vesicular stomatitis virus (VSV)-based technologies. GTx is developing VSV technologies for use as targeted viral cytolytic agents against HIV-infected cells and cancers.

Wyeth exclusively sublicensed to GTx patents covering VSV as cytolytic agents for use with GTx's VSV-based products. In return, Wyeth has an option to commercially license GTx's VSV-based anti-HIV product, GTx-v311. The preclinical candidate is a specially engineered VSV designed to target and eliminate HIV-infected cells.

"We've been operating under the radar, and now we're ready to come out," GTx CEO Mitchell Steiner told BioWorld Today. "We have proof-of-concept data in primates, and we're getting ourselves positioned by working out a deal with Wyeth, which is working in this area in vaccines. Together, their intellectual property and ours gives us full freedom to operate in this area."

GTx also granted to Madison, N.J.-based Wyeth a nonexclusive license to its VSV vaccine technology, in which recombinant VSV is used as a vector for delivery of vaccine antigens.

"This is a novel approach in that these viruses would seek out - almost surgically - these cells that contain HIV," Steiner said. "We're planning to meet with the FDA later this year and hope to be in Phase I/II, targeting drug-resistant HIV patients, by the beginning of next year."

VSV, a rhabdovirus, has been adapted for use as a cytolytic agent and gene delivery vector.

Specific financial terms of the deal were not disclosed, though the deal's value is very tangible to the 37-person, privately held company.

"As a small company, we're looking for capital, and we have invested so much in the technology we see that we can use it for other things as well that we have not licensed away," Steiner said. "For us to have bought all the intellectual property, it would have been very expensive. But licensing an option for our first product allows us access to that intellectual property and at the same time gives us full freedom to develop other aspects of the technology."

Founded in September 1997, much of GTx's private funding has come from both New York-based Oracle Partners LP and J.R. Hyde III, GTx's chairman who in 1979 founded AutoZone, also in Memphis. Steiner, who also is a urologist and molecular biologist, treated Hyde's prostate cancer and from that the two developed a relationship and eventually the company.

In addition to GTx-v311, GTx is developing VSV-based viral cytolytic agents against prostate and brain tumors. Preclinical rat studies are evaluating the technology's ability to remove tumors and their roots.

"We are going after pretty difficult tumors - metastatic prostate cancer and glioma," Steiner said. "To be able to have something that selectively removes tumors, in addition to surgery and hopefully one day replace surgery, would be pretty exciting."

Outside of its VSV technologies, GTx features a number of small-molecule programs in clinical development - selective androgen receptor modules (SARMs) and selective estrogen receptor modules (SERMs).

GTx's most advanced product, Acapodene (toremifene), is a SERM being studied in a U.S. multicenter, 500-patient Phase IIb/III trial to treat the premalignant region of prostate cancer. The drug could supplant the repetitive biopsy process that sometimes catches cancer too late.

"The time is perfect to come up with non-steroidal molecules that have very selective effects on tissues," Steiner said. "When we had the compound in preclinical studies, which we published in Cancer Research, we showed in animal models that we prevent this premalignant region and decrease the incidence of cancer."

He said GTx expects to receive data from the trial next year. At the same time, Acapodene studies continue in treating the complications of androgen deprivation - osteoporosis, hot flashes and the gynecomastic enlargement of breasts. Two Phase II trials, one for prevention and another for treatment, are completely enrolled. GTx expects data this quarter, with Phase III trials anticipated to begin in September.

GTx licensed Acapodene from Orion Pharma, the pharmaceutical division of Espoo, Finland-based Orion Corp., but it has yet to outlicense any of its small molecules.

In its SARM program, GTx's Andarine is entering Phase Ib trials to treat muscle wasting. The drug is designed to stimulate muscle and bone growth while inhibiting prostate cancer. Other products in development include Prostarine to treat benign prostatic hyperplasia and Libidarine to treat loss of libido.

GTx, which also has three anticancer programs in preclinical development, is involved in talks with potential partners interested in its SARM products. But Steiner said the company does not need to leap at its first opportunity.

"We've been fortunate, because if you're out of cash and desperate you can get taken advantage of," he said. "But we've done everything in a very deliberate way. We're not your typical company with 100 venture capital firms driving the story. We're just doing quality science and letting that science move the company forward."