Washington Editor

WASHINGTON - The FDA Tuesday posted safety analyses of 24 new drugs and biologics, such as Genzyme Corp.'s Renvela (Sevelamer carbonate), and two vaccines, including CSL Ltd. influenza vaccine Afluria, on its website as part of an effort aimed at informing the public in more detail about the most recently approved medicines.

The summaries, which will be posted quarterly on the agency's website, were mandated under section 915 of the FDA Amendments Act (FDAAA) of 2007, which requires regulators to conduct a comprehensive postmarketing evaluation within 18 months of a medical product's approval or after it has been used by 10,000 patients.

The products posted Tuesday are some of the first affected by the FDAAA statute, Robert Boucher, director of the Division of Pharmacovigilance II in the FDA's Office of Surveillance and Epidemiology, told reporters. He noted that there are about 30 more products currently completing the evaluation process, but summaries for those medicines will not be posted until the next quarterly report.

The summaries are based on information gleaned from adverse event reports from product manufacturers, health care providers and consumers reported to the FDA's MedWatch program and the Centers for Disease Control and Prevention, periodic data reported to regulators from drugmakers, medical literature and ongoing postapproval studies, Boucher said.

"We can't emphasize enough the importance of postmarketing safety reports," he said.

While medical products undergo many years of development and testing, with numerous methodologies applied to determine whether the medicine is safe and effective for a particular indication, "that process, as extensive as it might be, is not sufficient in and of itself to inform use in the real world," Boucher said.

Some adverse effects, he said, may not become apparent until after a medicine becomes available to a larger, more diverse population than the patients who participated in clinical trials that supported the product's approval.

Preapproval study populations, Boucher noted, are "not going to be enough" to identify rare adverse events, such as acute liver failure or a certain type of cancer.

"You would have to have a very extensive clinical trial if you were looking for that," he said.

In addition, preapproval studies tend to use the healthiest volunteers, even for those testing drugs for advanced cancers, Boucher said.

And most trials, unless they are designed to look at a specific population, will not generally include vulnerable groups, such as the elderly, children, or pregnant or lactating women, he added.

Boucher noted that once a drug is approved in the U.S. and enters the "real-world" marketplace, prescribers are permitted to use the products "as they see fit."

"So most approved drugs are used at one time or another for unlabeled indications," he said. "So that changes the whole game; it changes all of the dynamics, because you don't know if the drug is effective in that population, and because that population was not included in safety assessment, you don't have any data on safety either. But that's, in fact, what happens in the real world."

Boucher noted that FDA-approved labeling is designed to capture "everything that is known at the time of approval."

But once the product enters the market, serious safety issues, including life-threatening adverse events or death, often arise that likely would not have been predicted in clinical development, Boucher said.

For its summaries, the FDA is targeting only new molecular entities (NMEs) - those products with active ingredients not previously marketed - and original biologics, he said. The agency also is including non-NMEs, those products whose active ingredients have been previously approved but are now being marketed as a new formulation, new dosing regimen or in combination or for a new or expanded patient population, Boucher added.

The summaries may include information on potentially serious, previously unidentified risks or may state that no unlabeled or unexpected serious adverse events were identified, he explained.

Of the 26 products posted Tuesday, 18 were of the latter category, including Genzyme's Renvela.

"For the most part, we have not been surprised by anything we are seeing" in the first two years of the program, Boucher said.

He emphasized that the quarterly reported summaries of new drugs, biologics and vaccines "do not trump" the FDA's other drug safety communications.

For instance, the FDA in March recommended that clinicians temporarily suspend use of GlaxoSmithKline plc's rotavirus vaccine Rotarix, which appears in the FDA's summaries posted Tuesday. The agency two months later determined it was appropriate for clinicians and health care professionals to resume the use of the vaccine.

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