Abemaciclib in Children With DIPG or Recurrent/Refractory Solid Tumors

Stratum A- Appropriate dose RT will be administered in 30-33 fractions over approximately 6 weeks for Stratum A patients. Treatment with abemaciclib (LY2835219) will start on the same day as radiation therapy (RT) and continue twice daily during and after RT for a maximum treatment duration of 2 years. Investigators plan to treat a maximum of 4 cohorts of research participants (dosage levels 1, 2, 3, and 4) with escalating doses of abemaciclib (LY2835219) starting with dose level 1 (80% of adult dose). A cycle is defined as 28 days and the first 6 weeks of therapy will constitute the dose-limiting toxicity (DLT)-evaluation period. Participants must take abemaciclib by mouth as intact capsules. Stratum B (no longer enrolling) - Abemaciclib (LY2835219) will be administered orally on a twice daily basis continuously for 28 days, which defines one cycle. The maximum treatment duration will be 2 years. Investigators plan to treat a maximum of 4 cohorts of research participants (dosage levels 1, 2, 3, and 4) with escalating doses of abemaciclib starting with dose level 1 (80% of adult dose). Dose escalation will be independent of Stratum A escalation. A cycle is defined as 28 days and the first 4 weeks of therapy will constitute the DLT-evaluation period. Participants must take abemaciclib by mouth as intact capsules. Enrollment for Stratum B closed December 27, 2018.