Pediatric Cancer Therapeutics: Letter of Interest
The development of pediatric oncology agents merits special consideration. Compared to adult malignancies, pediatric cancers afflict smaller numbers of patients. Because the majority of patients receive their cancer therapy as participants in clinical research protocols, participation in oncology trials has become the "standard of care" in pediatric oncology. Children with cancer are usually treated at specialized centers by pediatric oncologists who are members of national pediatric cooperative study groups. One of the highest priorities of these groups is to develop improved novel therapies. Early access to new agents is the optimal mechanism to achieve this goal.
Known and potential differences in the biology of pediatric and adult tumors usually will not permit the extrapolation of clinical activity from adults to children. It will therefore usually be impossible to rely on pharmacokinetic and safety data alone to guide use of these agents in children and it will be necessary to evaluate the effectiveness and safety of new agents in pediatric populations. In most cases, in the absence of available therapy to treat refractory stages of most pediatric cancer, the Food and Drug Administration expects to be able to use the regulatory approaches of subpart H and E of our regulations in approving drugs for pediatric tumors, basing approval on an effect on tumor size or other surrogate markers likely to predict clinical benefit or based on safety in smaller numbers of patients.
To encourage the development of treatments for pediatric cancers, FDA expects to make Written Requests to sponsors of new drugs that may qualify a product for an exclusivity extension under the Food and Drug Administration Modernization Act of 1997 (FDAMA). In general, these requests will ask for early phase I studies to assess pediatric tolerability and seek potentially responsive tumors followed, if the drug is tolerated, by appropriate phase II studies in specific populations. If approval is based on surrogate endpoints or smaller safety numbers, subsequent further studies would usually be needed. To expedite this initiative we suggest that sponsors discuss a pediatric development plan with a pediatric cooperative study group to utilize their expertise and resources to optimize study design and patient accrual and to determine which cancers should be studied. Sponsors are encouraged to generate proposals for Written Requests in conjunction with pediatric cooperative groups prior to submission of the proposal to the Division of Oncology Drug Products.
Further information may be obtained at the FDA Internet site or by calling Steven Hirschfeld, MD, PhD in the Oncology Division at 301-827-1532 or the Pediatric Implementation Team at 301-594-7337 or 301-827-2350. With your cooperation we can achieve the goal of improving the treatment of pediatric malignancies.
Richard Pazdur, MD
Division of Oncology Drug Products