*2.2.2.2 Methods*

All subjects enrolled had cancer that was refractory to prior lines of treatment. Specifically, patients were required to already be at least three cycles into nivolumab treatment and must be planning to continue this treatment throughout the trial period. Thirty patients in total were enrolled, ten of which were in part 1 of this study, where they were treated with apatinib using a classic 3 + 3 dose escalation method in order to determine the maximum tolerated dose. Part 2 of this study included twenty subjects and was an expansion phase using the MTD. The percent of change in tumor responses and amount of time until progression were measured and analyzed using RECIST v1.1 and iRECIST criteria.
