By Randall Osborne

Nearing the finish line of its three-year, 2,500-patient Phase III trial of Remune, a therapeutic vaccine for HIV, Immune Response Corp. raised $10 million in a private placement.

"The trial is officially over at the first quarter of next year," said Charles Cashion, chief financial officer of Carlsbad, Calif.-based Immune Response. Interim analyses are slated for June and November.

Meanwhile, the company is conducting talks with potential collaborators on all of its programs. The placement "gives us a little bit of insurance and breathing room, and allows us to negotiate with greater strength," Cashion said.

In the financing, Immune Response placed $10 million of Series F convertible preferred shares, which are convertible during the first year at a fixed price of $14.07, which is a 20 percent premium over the average closing market bid price during the five days before the transaction was completed.

Maturity date for the shares, which bear a 7.5 percent annual dividend payable quarterly, is April 2001.

Prudential Securities Inc., of New York, served as advisor for the placement.

Remune Expected To Complement Existing Drugs

Remune is inactivated HIV combined with a mineral oil-based adjuvant and is designed to stimulate a patient's own immune defenses to fight the virus. Through purification, the killed HIV loses glycoprotein (gp) 120, an envelope protein that helps the virus infect cells.

"We are confident it will complement [existing] drugs," Cashion said. "They drive down the viral load, but they don't boost the immune system."

Another Immune Response product is IR501, a T cell receptor peptide vaccine for rheumatoid arthritis, which performed favorably in its first Phase II trial. (See BioWorld Today, Jan. 8, 1997, p. 1.)

"Results were better than statisticians expected when the study was designed," Cashion said. A second Phase II trial is under way to confirm the results, and is expected to finish by the end of the year.

The HIV and the arthritis drugs contrast with other drugs for the conditions, which must be taken more regularly and entail severe side effects. Remune is injected once every three months. IR501 is injected once per month for three months, and once every three months after that.

IR502, a compound similar to the arthritis drug but designed for use against psoriasis, failed to show a difference between control and treated groups in a Phase II study. Another Phase II trial of IR502 is ongoing.

"The protocol was redesigned," Cashion said. "There was a belief that, as a result of the first Phase II ending during the summer, there may have been a greater impact from the sun [exposure to which may ameliorate psoriasis]. This trial was recruited after the summer and conducted in the winter."

Immune Response has earlier stage products in cancer vaccines and gene therapy. With its partner Sidney Kimmel Cancer Center, of San Diego, the company has tested a vaccine for colon cancer in a Phase I trial.

"We're in the process of conducting a second Phase I in colon cancer with an improved compound," Cashion said.

The company has a collaboration with Vyrex Corp., of La Jolla, Calif., for development and discovery of proteins and small molecules involved in nerve growth and repair. (See BioWorld Today, March 10, 1997, p. 1.)

That deal focuses on spinal cord injury, Cashion said. "It's probably the earliest-stage program we have under way," he added. Another collaboration is with Bayer AG, of Leverkusen, Germany, in a gene therapy program for hemophilia.

At the end of last year, Immune Response had $30.4 million in cash, with a net loss of $33.5 million for 1997.

The company's stock (NASDAQ:IMNR) closed Thursday at $12.187, down $0.562. *