A Study of Abemaciclib in Combination With Sunitinib in Metastatic Renal Cell Carcinoma

Subjects will by given oral Abemaciclib every 12 hours for 14 days followed by 7 days off (i.e. a 21 day cycle). The initial dose will be 100 mg (Dose level 1) followed by 150 mg (Dose Level 2) depending on tolerability and toxicity assessment of the combination of medications. If at Dose Level 1 subjects cannot tolerate the combination of medications, the Abemaciclib would not be increased, and the dose will remain stable at 100 mg (Dose Level -1).

Subjects will take oral Sunitinib daily for the 21-day cycle. Dosing will be at 50 mg for both Dose Levels 1 and 2. If the combination of the 2 medications is not tolerated by Subjects at Dose Levels 1 a lower dose of Sunitinib (37.5 mg) will be given (Dose Level -1).