By Debbie Strickland

Cor Therapeutics Inc. lost half its share value Thursday in the wake of an FDA advisory panel's limited recommendation for approval of Integrilin, an anti-clotting agent that targets the same biological receptor as Centocor Inc.'s blockbuster drug ReoPro.

Cor's stock closed Thursday at $9.438, down 53 percent from Wednesday's $20 close (trading was halted Wednesday for the FDA hearing). Integrilin partner Schering Plough Corp.'s shares (NYSE:SGP) closed at $75, up $1.25.

"While we had expected a recommendation from the advisory committee for a broader indication, the fact remains that the committee has unanimously recommended approval for Integrilin in angioplasty and we look forward to FDA approval in the near future," said Vaughn Kailian, president and CEO of South San Francisco-based Cor.

Both Kailian and his company's spokeswoman, Laura Brege, were traveling Thursday and unavailable for additional comment.

Schering-Plough, meanwhile, is optimistic about Integrilin, despite the "disappointing" decision, said Ron Asinari, spokesman for the Madison, N.J., pharmaceutical firm.

The companies will seek "optimal labeling" in their upcoming discussions with FDA officials, he told BioWorld Today, and will continue to pursue "broader indications, including acute coronary syndromes."

Integrilin, an inhibitor of platelet aggregation, is a synthetic peptide derived from the venom of the Southeastern pygmy rattlesnake. The drug specifically blocks the GPIIb-IIIa receptor, which binds fibrinogen and mediates platelet aggregation.

With the backing of a successful 11,000-patient Phase III trial, Cor and Schering-Plough had sought approval of Integrilin as a treatment for unstable angina, a broad indication that could generate sales upwards of $300 million, according to analysts. Instead, Cor won the Cardiovascular and Renal Drugs Advisory Committee's unanimous endorsement for use of Integrilin in a much smaller segment of the market: patients undergoing balloon angioplasty.

After the committee decision Wednesday, analyst Matt Geller revised his projections for the company. With an unstable angina approval Cor could have attained profitability in 1999, but now, Geller predicted, it looks like the firm will continue to lose money into 2000.

Geller, who covers Cor for CIBC Oppenheimer, in New York, expressed surprise over the panel outcome, but added that "this particular FDA panel, [along with] the Cardio-Renal division headed by Raymond Lipicky, firmly believes that two successful trials are necessary for product approval."

Cor did conduct two Phase III Integrilin trials, but the first examined the drug only in patients undergoing balloon angioplasty. Cor attempted in early 1997 to win approval for that indication on the strength of the lone Phase III trial, but failed to gain the advisory panel's backing.

Though the committee is now satisfied the drug works in angioplasty, it declined to recommend the drug for unstable angina on the basis of results from a single pivotal trial.

Agency officials could still defy the committee's advice and approve Integrilin for unstable angina, but Geller said the likelihood of such an event is only 20 percent.

Regardless of the fate of its lead product, Cor has enough cash -- $82.6 million as of Dec. 31, 1997 -- to last through 1999, thanks to a $55 million public offering that closed in October, the same month the company's shares hit their highest level of the year, $25.50.

The stock hovered mostly in the $20 to $23 range during the three months leading up to the panel meeting.

With Centocor's ReoPro "well established as the anti-clotting agent of choice" for angioplasty patients, Geller estimates the "fair value" of Cor's stock at $10, a price with which the market apparently concurs.

Centocor Inc.'s stock surged $5, or 14.5 percent, to $39.375 Wednesday on news of its rival's misfortune, but gave back $1 of the gain Thursday, the same day it released its 1997 earnings report touting sharp ReoPro gains.

A monoclonal antibody drug marketed by Indianapolis-based Eli Lilly and Co., ReoPro sales shot up 70 percent to $254 million in 1997, with Centocor realizing $158.4 million on ReoPro sales to Lilly.

Driven by its lead product, Centocor, of Malvern, Pa., recorded its first full year of profitability in 1997, with earnings of $11.1 million on revenues of $200.8 million.

Centocor won a label expansion in November, allowing the marketing of the drug for prevention of cardiac ischemic complications in a broad range of patients undergoing percutaneous coronary intervention

The product's original, December 1994, approval was for use in high-risk angioplasty patients. *