It's really only in the last decade that clinical trials - even in the U.S. and Europe - have started to focus on children, said Dr. Dianne Murphy, director of the U.S. Food and Drug Administration (FDA) Office of Pediatric Therapeutics.

Since children cannot give informed consent to enter a study (their parents have to do it), kids have historically been left out of clinical trials testing vaccines, drugs and other therapies.

But that's a problem, Murphy explained, because children are not small adults, and study results from adults cannot simply be extended to them.

"We don't know if we're giving them the right dose, or if it's even going to be effective," Murphy explained.

So pediatric clinical trials are necessary. But since most children are, fortunately, healthy, researchers have to cast a wider net for study participants.

"You do have to reach out to more countries and more locations," Murphy said.

And that has led some to question whether there could be an inappropriate shift to countries where ethical guidelines - like making sure parents give truly informed consent - might not be closely monitored.

In the new study, however, Murphy and her colleagues found that the number of pediatric clinical trials in developing countries has actually declined in recent years. And the U.S. remains, by far, the most common trial location.

Of 346 pediatric trials the FDA reviewed, the U.S. participated in 86 percent, providing three-quarters of the patients. Less developed and transitional countries, like Mexico, Brazil and India, took part in 22 percent and accounted for 10 percent of all kids involved.

The figures come from trials submitted to the FDA in support of therapies approved between 2007 and 2010.

Developing nations, the agency found, played a smaller role in those trials than they had just a few years earlier.

In an earlier study of trials submitted between 2002 and 2007, the FDA found that developing countries took part in 38 percent of trials, and accounted for almost one-quarter of patients.

Those numbers will naturally shift depending on the diseases and treatments being studied in a given time period, Murphy noted.

If there are more trials testing vaccines or treatments for infectious disease, developing nations will tend to be more involved. And that's appropriate, Murphy said, because those diseases are a far bigger problem in developing countries.

"Children shouldn't be in a trial unless there's an opportunity for them to benefit," Murphy said.

The researchers didn't find evidence that kids in developing countries were being recruited into trials for diseases that are irrelevant to them. Of children enrolled in Mexico, for example, 97 percent were involved in vaccine trials.

In addition, most trials being done in developing countries (75 percent) were also running in wealthy ones.

Murphy said the FDA is taking steps to ensure that pediatric trials are being done appropriately. "For one," she noted, "everyone should be aware that we're reviewing this. That alone is important."

But she said the agency also offers training to regulators in other countries, and has regular conference calls with officials in developing nations to help them with "in-the-weeds kinds of questions."

"These conversations, particularly for (trials with) children, are very important," Murphy said.

Continuing to do trials involving kids is also vital, according to Murphy.

"If we don't, then your child becomes an experiment of one," she said, noting that research suggests that products that work for adults' ills do not work for children about one-fifth of the time.

SOURCE: bit.ly/UwOXbC Pediatrics, online November 5, 2012.

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