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Is there a novel path for Obesity development? – Hope springs eternal with the FDA


Limited use.  Targeted populations.  Smaller trial sizes.  Faster approvals.  These are the traits of cancer drug development, not obesity, correct?

The FDA's top drug administrator Janet Woodcock, made comments in support of legislation that would potentially include obesity in a regulatory world typically reserved for smaller populations.   Article text below.

The cynical FDA observer may say "easy to say, but let's see if they follow through."  Nevertheless, is it possible to promote any development in obesity with the austere and costly regulatory pathway established?  Recent history would say no.  If the FDA is open to the Special Population designation reinvigorate development  in novel injectable/peptide development and away from the re-packaging of older, albeit safety-challenged, small molecules currently in front of the FDA?



SECTION: Vol. 18 No. 11


LENGTH: 768 words


FDA's top drug official signaled support for a legislative proposal to approve drugs limited to targeted patient populations based on smaller clinical trials, saying obesity drugs could also be a candidate for the designation, although companies and physicians would have to assume responsibility for ensuring that only patients designated by the limited approval would receive the drug. An obesity treatment advocate said the new pathway could be valuable for obesity drugs so long as it is not too restrictive.

Drug center chief Janet Woodcock said the proposed new approval designation, which was recently floated by the Infectious Diseases Society of America to facilitate antibiotic development, could be useful for drugs beyond antibiotics.

"It's a solution to a problem we have in multiple disease areas, the problem of drugdevelopment," Woodcock said. "For example, with obesity drugs that raised blood pressure, we'd have to have a gigantic cardiovascular study potentially to rule out the kind of effects we saw with sibutramine. But it might be, if you studied people that had severe symptomatic diseases, that uncertainty would be tolerable."

Ahead of a congressional hearing on the Prescription Drug User Fee Act Thursday (March 8), the IDSA proposed a new FDA approval mechanism and is seeking its inclusion in the Generating Antibiotic Incentives Now (GAIN) Act, which outlines incentives to foster the development of antibiotics. IDSA said the Special Population Limited Medical Use (SPLMU) designation would mimic orphan drug destinations and accelerate antibiotic development by allowing companies to conduct smaller, more targeted clinical trials. FDA would give thedrugs a special logo and labeling to outline their intended population. IDSA crafted the proposal to spur the development of antibiotics targeting serious infections that lack treatments.

The limited use idea could fit nicely with obesity drugs. Woodcock said obesity that has progressed to the point where a person is no longer mobile is an example of a symptomatic disease and that the benefit risk issues would be different for people with severe obesity than the general population, with the ability to walk around being a possible clinical endpoint. But she emphasized that FDA would try to restrict use of the medication and the manufacturer would have to conduct safety studies in a broader population before it could be approved for general use.

"In the meantime, though, those people who really needed it and had the tremendous burden of disease would actually be able to get that effective treatment," she said after the hearing.

In the case of antibiotics, infectious disease experts expect the limited use antibiotics to be more expensive and have a less-known risk profile because approvals would be based on small clinical trials. Therefore, the limited use approvals would likely foster judicious use programs among payors and healthcare providers.

Woodcock said FDA has been discussing different ways to stage small development programs and that several had been pitched to the agency by industry without the inclusion of restrictions or special designations, but the agency wanted a "big flag" about how the drugsshould be used. She said the agency is receptive to the IDSA proposal but it will require a social contract between the agency, industry and infectious disease control formularies against off-label prescribing.

An advocate for obesity treatment said the special use designation could help get obesity medications out faster to those who need them most but said he was concerned that restricting the drugs to very small populations would do little to resolve the problem. "If this represents a means to obtaining more treatment options for the obese people who were most in need of treatment, it would be good," said Patrick O'Neil, president of The Obesity Society.

O'Neil said SPLMU could be a valuable pathway for obese drugs but that if the targeted population were too small, drugs approved through the small development program would do little to address the needs of obese people, who he said account for one-third of the U.S. population.

O'Neil said there is a risk of misuse or inappropriate prescribing with any medication and agreed with the agency's stance on off-label use of drugs like obesity medications, which have a high potential for misuse and carry cardiovascular risks. "The level of restrictiveness of prescribing should reflect the demonstrated risk of inappropriate prescribing and also the consequences to patients who receive those prescriptions," he said. -- Stephanie Beasley