By Kim Coghill

Washington Editor

The Immune Response Corp. (IRC) likely will find a new partner to help develop Remune following Agouron Pharmaceuticals Inc.¿s decision to terminate its collaboration on the HIV product.

Jim Glavin, chairman of Carlsbad, Calif.-based IRC, said IRC Thursday afternoon received notification via registered mail that Agouron intends to end its three-year-old development and commercialization deal for Remune (HIV- Immunogen).

IRC will regain full rights in the U.S., Europe, Japan and certain other countries and Agouron has said it will cooperate with IRC for an orderly transition.

Remune is currently the subject of several clinical trials, including a Phase III study sponsored by Agouron to evaluate the product¿s effect on viral load when administered in combination with potent antiviral drug therapy. The study should be unblinded sometime next year.

Agouron, of La Jolla, Calif., entered the collaboration with IRC back in 1998, six months before it was acquired by Warner-Lambert in a $2.1 billion deal. Warner-Lambert later merged with American Home Products Corp. and was acquired by Pfizer Inc., of New York. (See BioWorld Today, Jan. 27, 1999,and June 12, 1998.)

¿We haven¿t had a chance to meet with them and to define what cooperative transfer of development responsibilities mean,¿ Glavin told BioWorld Today. ¿Obviously, the continued funding of the Phase III trial through the middle of next year will be one of the things that I will want to talk to them about as part of this cooperative transfer. But fair is fair, the way I see it. We have responsibilities and they have responsibilities to patients, physicians and the product itself, and that will be part of the discussions as we move away from each other.¿

Glavin said IRC is committed to continuing development of Remune, ¿but we have to find the wherewithal to do so. We clearly are going to need funding to continue this development, but it is too early to discuss this now. ¿

In addition to conducting the Phase III study, Glavin said Pfizer has paid IRC about $47 million in quarterly payments, with the last payment occurring about six months ago.

Under terms of the original deal, IRC was scheduled to receive up to $77 million over two years, including a $10 million up-front licensing fee and another $35 million in milestone payments, plus $18 million in support development. (See BioWorld Today, June 12, 1998.)

Agouron would not comment beyond its written statement that said the decision to withdraw was based on review of data from several clinical trials.

¿The safety profile of Remune was not a factor in our decision to withdraw from its development program,¿ the statement said. ¿The decision to withdraw from Remune¿s development program should not be interpreted to mean that immune-based therapies, as a class, do not merit further investigation.¿

Remune has had a fairly rocky history that has caused IRC¿s stock to yo-yo. Friday the stock (NASDAQ:IMNR) closed at $2.58, down $2.01, or 43.8 percent.

For example, in early June, IRC¿s stock dropped 55.5 percent to close at $2.18, down $2.72, when a Phase II study of Remune in Spain failed to meet its primary endpoint. An independent data safety monitoring review board found no significant difference for the Remune group. The primary endpoint was time to increase to 5,000 copies/ml of viral load (the amount of HIV detected in the blood) or a 50 percent decrease in CD4+ T cells/ml or a decrease to less than 250 CD4+ T cells/ml while on antiretroviral therapy. (See BioWorld Today, June 4, 2001.)

But in mid-June, IRC¿s stock jumped 155 percent, from $2.43 to $4, when Trinity Medical Group USA Inc., of Rancho Santa Margarita, Calif., presented data at the Eleventh Symposium of HIV Infection, held in Toulon, France, showing that long-term Remune treatment is safe and resulted in increased CD4 and CD8 T-cell count and body weight.

And in April, the stock jumped 58 percent to close at $2.58, up 95 cents, on publication of data in a European journal showing patients treated with Remune had a reduction in viral load regardless of concomitant antiretroviral drug therapy. The study showed that Remune induces HIV-specific, T-helper-cell immune responses that correlate with the amount of HIV in the bloodstream. The data were in the April edition of HIV Medicine, the journal of the European AIDS Clinical Society and the British HIV Association. (See BioWorld Today, April, 24, 2001).

A Phase III trial of Remune was halted in May 1999 when an independent data safety monitoring board determined that the 2,500-patient, 120-week study could not meet its primary endpoint of reducing the rate of disease progression. (See BioWorld Today, May 18, 1999.)

A year later, the company stopped enrollment in a 472-patient Phase III trial of the drug with highly active antiretroviral therapy in order to adjust the protocol. (See BioWorld Today, June 22, 2000.)