By Frances Bishopp

ImmuLogic Pharmaceutical Corp. has reported positive preliminary results from its Phase III Allervax Ragweed clinical trial which indicated the eight-dose 250 microgram group of the product significantly reduced patients' ragweed allergy symptoms and reduced medication use across the ragweed allergy season.

Peter Ginsberg, an analyst with Vector Securities International, of Deerfield, Ill., said the data is quite positive for ImmuLogic. The negative news, however, is because that dosing regimen hasn't been used in previous trials, the company will be required to do another study before filing for approval. There will be most likely a one-year delay, Ginsberg said.

ImmuLogic stock (NASDAQ:IMUL) gained $0.75 Tuesday to close at $6.50.

The 1996 Allervax Ragweed trial of 500 patients was conducted at 22 centers and composed of five patient groups, each made up of 100 patients.

Another objective of the study was to evaluate the efficacy of the Allervax Ragweed four-dose 750 microgram group compared to the four-dose placebo group in reducing the rhinoconjunctival symptom-medication index across the season. The improvement seen in this trial was consistent with the improvement seen in the 1995 Phase II ragweed trial, Joseph Marr, acting president and CEO of ImmuLogic, of Waltham, Mass., told BioWorld Today. However, this improvement was not statistically significant.

The Phase II clinical trial on the four-dose study, Marr said, had more people, 320 vs. 100 in the Phase III study, and showed the same kind of clinical results, but did not achieve statistic significance.

"The 250 dose study showed statistical significance even with a smaller trial," Marr Pointed out.

"Since we had activity in the lower dose, which we didn't expect, we are going to do another trial in the next ragweed season, beginning in July, with the same protocol, prove it again and take it to the FDA for approval," Marr said.

"Our safety profile for Allervax Ragweed is excellent; the side effect increase over placebo in the Phase III study was only 4 percent, " he said.

"We are really happy about this," Marr said. "These Allervax products can be a reality. It is not a question anymore whether or not they are going to work, it is a question of how well they are going to work and how long it is going to take to prove them."

ImmuLogic's Allervax program develops peptide immunotherapeutics that desensitize patients to common allergy-producing substances. When patients are injected subcutaneously with an Allervax product, specific peptides are recognized by their corresponding helper T cells. Because the T cells receive no second signal to confirm the presence of an invader, they become nonresponsive. As a consequence, the patient's T cells do not respond on subsequent exposure to allergen and their allergy symptoms are lessened or eliminated.

A primary efficacy objective of the Phase III study, the rhinoconjunctival symptom-medication index comparison of the eight-dose 250 microgram group to eight-dose placebo group, was statistically significant with an improvement of 17 percent across the season.

In addition, the 250 microgram dose group demonstrated an important objective secondary measurement of efficacy, a 39-percent reduction in decongestant and antihistamine medication use across the season.

Additional secondary endpoint measurements include comparisons between the Allervax Ragweed treated groups and an observational group, which did not receive any treatment. A 31-percent improvement was seen in the rhinoconjunctival symptom-medication index for the eight-dose 250 microgram group compared to the observation group.

Medication use was 54 percent lower in the eight-dose 250 microgram group compared to the observation group. An analysis of the IgE antibody responses across the season, another secondary endpoint, did not show significant differences among groups.

While expressing confidence in the results seen in patients receiving the 250 microgram dosing regimen, Ginsberg said, "we cannot look past the fact that our approval timeline has been extended by a full year, causing our price target to fall significantly to $11 from $17."

Marr said ImmuLogic currently is discussing collaborations with companies to create new partnerships. Hoechst Marion Rousell, of Kansas City, Mo., ended a collaboration with ImmuLogic in 1996, as well as with two other companies, Alteon Inc., of Ramsey, N.J., and Scios Inc., of Mountain View, Calif.

At the time, ImmuLogic's stock fell 22 percent on the news.

"That set us back in the investment community," Marr said, "because they thought something was wrong. There was nothing wrong, Hoechst had reevaluated what areas it wanted to be in and this was not one of them. They sold the stock and made money on it."

In December 1996, ImmuLogic stock plummeted 17 percent after the company revealed the resignation of its president and CEO, Richard Gerety, and the planned departure of its chief financial officer, Richard Small.

Company officials did not reveal the reason for Gerety's resignation, but did say it was not related to Small's departure.

ImmuLogic, Marr said, currently has $70 million in cash, at least "three years of cash." *