Dangerous Pfizer drug effective: researcher

ORLANDO (CNNMoney.com) -- A researcher unveiled on Monday the results of a failed Pfizer Inc. study showing that an experimental but dangerous cholesterol drug offers medical benefits too significant to be ignored.

The drug, torcetrapib, which Pfizer discontinued last year because too many patients died in the study, was nonetheless very effective in controlling cholesterol levels, said Dr. Phillip Barter, lead researcher in the study and professor of the Heart Research Institute in Sydney, Australia.

Pfizer released results of a study showing that a dangerous cholesterol drug has significant medical benefits.

The dangers associated with torcetrapib were already well-known, but its benefits had not been disclosed in detail before Monday. The test results could re-ignite interest in this class of drugs, known as cholesterol ester transfer protein inhibitors and is of great significance to other companies as well as Pfizer.

"This class of drugs has the potential to save so many lives," said Barter.

Torcetrapib increased high-density lipoprotein cholesterol, a beneficial type of cholesterol known as HDL, by 72 percent, in a study involving more than 15,000 patients, according to Barter, who spoke about the results at the annual conference of the American Heart Association.

Barter also said the drug decreased a harmful type of cholesterol, known as low-density lipoprotein or LDL, by 25 percent.

Pfizer Inc. (Charts, Fortune 500) had intended to add torcetrapib to the cholesterol treatment Lipitor, the world's top-selling drug with nearly $13 billion in 2006 sales. But of the 7,533 patients who took Lipitor with torcetrapib, 93 died and 464 suffered "major cardiovascular events," said Barter.

Among the nearly identical number of patients who took only Lipitor, 59 died and 373 experienced major cardio events. These events include death from heart disease, as well as non-fatal heart attack, stroke and hospitalization from chest pain.

Pfizer had believed that adding torcetrapib to Lipitor would make it more competitive against low-cost cholesterol drugs that recently lost patent protection, such as Merck's (Charts, Fortune 500) Zocor and Bristol-Myers Squibb's (Charts, Fortune 500) Pravachol. Also, Pfizer hoped that the combo would have kept Lipitor sales from plunging after its patent expires in 2010.

Without torcetrapib, Pfizer now faces an impending sales vacuum when Lipitor becomes open season for generic manufacturers, unless the company can fill its pipeline with potential blockbusters.

Even though the torcetrapib study was dropped last year, the study results were closely watched on Monday because of their potential impact on other drug companies. Analysts and medical experts say that Merck and Roche (Charts) are experimenting with cholesterol drugs from the same class as torcetrapib, and Pfizer's results could determine whether they bother to continue.

"What this study does is it leaves the way open for further exploration," said Barter. "Hopefully the huge public benefit of this drug will be realized."

But for now, researchers aren't even sure what caused the torcetrapib patients to die.

Dr. Steve Ryder, a clinical research executive for Pfizer, said his company has conducted - and suspended - two additional torcetrapib studies, though they were much earlier stage than the large study that was unveiled on Monday.

Les Funtleyder, an analyst for Miller Tabak, said the CETP inhibitors could be lucrative additions to the $20 billion cholesterol market, despite the potential of dangerous side effects.

"The FDA is going to be hyper-sensitive to safety concerns in this class, and that will also be true of prescribing physicians," said Funtleyder. "But if they can find the appropriate population for this class of drugs, you've got a significant commercial opportunity."

In another development announced Monday at the AHA conference, AstraZeneca reported that its cholesterol treatment Crestor reduced cardiovascular death, stroke and heart attack by a mere 8 percent.

The drugmaker's stock slipped 1 percent, but the fallout is minimal. Crestor is already an FDA-approved blockbuster. Sales of the drug soared 42 percent during the first nine months of 2007, reaching nearly $2 billion.

Merck had better luck with its study of the experimental cholesterol drug Cordaptive, which has been submitted to the FDA.

The drugmaker said that Cordaptive, when added to its drug Zocor, lowered harmful types of cholesterol and increased beneficial types with greater effectiveness than Zocor alone. Those taking Cordaptive reduced low density lipoprotein by 48 percent and triglycerides by 33 percent, but raised high density lipoprotein by 28 percent, Merck said.

Zocor, also known by its generic name simvastatin, was a best-seller until its patent expired in 2006. This opened up the drug to generic competition, which caused sales to plunge.