Pharmaceutical companies have trouble making the drugs into liquids that are palatable. While McKinney thinks some drug companies drag when it comes to work on pediatric formulations, he said low economic incentive isn't the only barrier to development. There's a market factor, of course, but there are some companies that have legitimately tried. Merck has probably spent millions trying to develop a pediatric version of their drug. Burroughs Wellcome also moved AZT to the pediatric arena relatively early, Katz added.
Sheer numbers play another part in the slow move of medications from adult to pediatric trials.
The pool of infected children remains comparatively small at tens of thousands worldwide. With fewer patients, there are fewer eligible for studies, and even those available can pose problems. With adults fighting HIV and AIDS, there's an eager population ready to try new drugs and get involved in studies, Katz said. With children, getting permission for their participation in trial treatments and getting the patients enrolled is more complex. The youngsters have sick parents, or overburdened relatives or foster parents, who must deal with regulations.