Novel agents in development for pediatric sarcomas.

PURPOSE OF REVIEW: The survival curves for many pediatric sarcomas have remained flat for the past 2 decades or more and novel therapeutics - those small molecule medicines that selectively inhibit specific signaling molecules - have been slow to enter into pediatric practice. The preclinical basis for their use is reviewed here. RECENT
FINDINGS: Preclinical and phase I studies showing efficacy of antiinsulin-like growth factor receptor 1 therapies for Ewing sarcoma have led to numerous ongoing clinical trials using these agents for Ewing and other sarcomas. Early studies of ERBB signaling as a target in sarcoma therapy have been tantalizing, but progress in this area has been controversial. In-vitro analysis of Src inhibitors suggested that these agents would prevent metastasis in osteosarcoma, whereas in-vivo analysis showed no effect on metastasis, underscoring the need for thorough preclinical investigations of promising new therapies to guide future clinical trials. Antiangiogenic and immunomodulatory therapies are gaining momentum in the pediatric arena and should be tested in combination with traditional cytotoxic agents for recurrent and high-risk primary pediatric sarcomas.
SUMMARY: Pediatric sarcomas have diverse biology and distinct signaling pathways, making detailed preclinical evaluation of small molecule inhibitors essential to guiding the design of further clinical investigations.