Children with cancer are less likely than adults to be able to get the latest chemo drugs. Many new forms of chemotherapy are tested only in adults and aren't offered to pediatric patients until years later. But improvements in the laws that govern how pharmaceutical companies run clinical trials could change the situation, according to a recent editorial in Nature.
As the editorial explains, children make up just 1 percent of U.S. cancer patients, and they have unique characteristics that may make pharmaceutical companies reluctant to include them in clinical trials:
Designing a clinical trial is never simple, but adding children to the picture complicates the process immensely. Children are not just ‘small adults’ — they metabolize drugs in very different ways. It is difficult to predict from adult or animal studies whether a chemotherapy drug will be more or less toxic in a child, and at what dose. The process of obtaining informed consent for children participating in a trial can also be more complicated. And companies fear that the death of a child — even if unrelated to the treatment — could bring bad publicity for a new drug.
Lawmakers have tackled this problem before; for example, a 2003 law called the Pediatric Research Equity Act requires companies to plan how they will test experimental medications in children, and it's been helping. But the existing laws still have loopholes:
For instance, therapies for conditions that do not affect children — such as Alzheimer’s disease — are exempt from the PREA. And exemptions intended for such diseases have been broadly applied to cancer. For example, therapies that are being trialled in adults with breast cancer are exempted because children do not get that cancer, even if the drug could treat a childhood cancer in a different organ.
Closing such loopholes is especially important as our fight against cancer changes, the editorial concludes. Cancer used to be classified and treated based its location in the body; today, we can group tumors according to their genetic similarities instead. That advance lets us target chemotherapy drugs to tumors' metabolic weak spots, which may be shared across cancers that affect many different age groups. As the old divisions in how we think about cancer are broken down, we also need to break barriers that prevent the youngest cancer patients from getting help from cutting-edge cures.
Previously: California collaboration focuses on analyzing pediatric cancers, Existing drug shows early promise against deadly childhood brain tumor and A look at the dramatic improvement in pediatric cancer survival rates
Photo by Eleazar Cruz