Pfizer heart drug might be next big thing

Pharmaceutical giant Pfizer Inc., in a drug-development slump for the past several years, suddenly has hit the sweet spot.

A study involving thousands of patients taking Pfizer's experimental heart drug apixaban, developed in conjunction with New Jersey-based Bristol-Myers Squibb, has shown that the potential blockbuster is effective against stroke and blood clots in patients with atrial fibrillation, the companies announced.

People with atrial fibrillation, marked by irregular heart rates, have symptoms ranging from poor blood flow and heart palpitations to shortness of breath and general weakness.

New York-based Pfizer said Thursday that it stopped a late-stage clinical trial of apixaban a few months earlier than expected after an independent data monitoring committee indicated the study had "revealed clear evidence of a clinically important reduction in stroke and systemic embolism" in a specific population. The drug was tried on patients considered unsuitable for the standard anti-clotting therapy of wayfarin, a drug whose known side effects include hemorrhages and osteoporosis.

"This announcement is clearly a positive surprise," said New York-based healthcare strategist Les Funtleyder of Miller Tabak & Co. in a note to investors Friday.

He added that a similar blood-clot drug from Johnson and Johnson called Xarelto "was thought to be in the lead" in reaching market for this new class of therapies, but apixaban's success in clinical trials may allow it to "leapfrog" other new remedies to become the first of its kind to win regulatory approval.

In the past two weeks, Pfizer also has announced successes with its hypertension treatment Inspra and lung-cancer drug crizotinib, though none of the drugs was discovered in Groton, where Pfizer has its largest research site worldwide.

But the news on apixaban may be the best yet for Pfizer, because of the drug's huge potential market. The industry blog FiercePharma has said a Barclay's analyst has projected annual sales of the treatment at $3.6 billion in a market expected to hit $12 billion in the coming years.

Pfizer stock rose 55 cents Friday to $15.46 a share, an increase of 3.7 percent. Bristol-Myers stock finished at $25.08, up 1.8 percent.

Three years ago, Pfizer gave Bristol-Myers Squibb $250 million up front and promised up to $750 million in milestone payments to help develop apixaban. Pfizer also agreed to pay 60 percent of the development costs going forward.

It's unknown how the two companies will split profits from the drug, if it is approved by the U.S. Food and Drug Administration.

Pfizer said an interim analysis of apixaban's safety placed it in the "acceptable" category when compared with aspirin. No specific results from the 36-country study, involving 5,600 people, were released.

In a total of nine separate late-phase drug trials, apixaban is being studied for a variety of conditions in about 60,000 patients worldwide, Pfizer said.

l.howard@theday.com