Eye on Washington: Focus on pediatric exclusivity and preventing drug abuse

July 1, 2007

Update on pediatric drug exclusivity legislation and report on how adolescent brain scan images can help prevent drug abuse.

• FDA: Let pediatric testing continue

Two-thirds of drugs prescribed for children still have not been tested for use in children. The Food and Drug Administration (FDA) would welcome continuation of the current laws that encourage and sometimes mandate such studies, an FDA representative told members at a Congressional hearing recently.

"We are just getting on a roll," in getting studies done, said Sandra Kweder, MD.

At the House committee hearing, Richard Gorman, MD, chair of the American Academy of Pediatrics pharmacology section, testified that, "in the last decade we have gained more useful information on drugs through BPCA and PREA than we had in the previous 70 years."

As it revamps the two laws, the provision Congress seems most likely to modify is the "exclusivity" clause under BPCA. This has likely been the most effective part of the law in getting research done. For 10 years it has given companies six additional months on a medication's patent if the FDA requests pediatric studies be done on the drug and the company does them.

Those terms have often proved attractive to manufacturers, and there is little question about their positive effect for health. But a number of groups and members of Congress have questioned the monetary gain some manufacturers get in exchange for the studies.

A study in the February 7 Journal of the American Medical Association, looked at nine products that were granted the extra six months and found that manufacturers' return for doing the studies ranged from –0.68 to about 74 times their costs and up to half a billion dollars in extra sales.

On the other hand, studies done under the exclusivity clauses have generated labeling changes for 128 products, including 83 where a product's use was expanded to broader pediatric populations, and 28 that substantiated the products were not safe and effective for children, the FDA said.

The Government Accountability Office calculated that 87% of the drugs granted the pediatric exclusivity have had important labeling changes. Some of the studies showed "that children may have been exposed to ineffective drugs, ineffective dosing, overdosing, or previously unknown side effects."

Kweder stressed that before the FDA requests studies in return for exclusivity, it looks at whether such trials will have "meaningful public health benefit for children."

"It's really difficult to assign a dollar amount to the public health benefit ...We have not been in the position where we have had to make those determinations of what the sponsor is likely to get out of this," Kweder explained.

The Senate passed reauthorization of the laws as part of its Prescription Drug User Fee Amendments on May 9. That version of the legislation scales back to three months the possible extended exclusivity manufacturers may get for a drug with annual earnings of more than $1 billion.

The other law up for renewal, PREA, requires pediatric studies of certain medications and biologics for indications that are approved or for which approval is sought. It has been credited with at least 55 labeling changes. The House Committee on Energy and Commerce approved its version of the legislation on June 21. It is expected to be considered by the House of Representatives in the near future.

• This is your brain on drugs

Brain scan images from drug abuse research have turned out to be wonderful tools to feed back to adolescents about how drugs affect the brain, says a special assistant to the director of the National Institute on Drug Abuse (NIDA).

Scans show, for instance, "lots of red hot activity throughout the cortex," in a normal person. For a marijuana abuser in the same situation, he or she is not able to marshal the same level of frontal or anterior lobe activity, and the colors are subdued.