Pembrolizumab and Anlotinib in the Treatment of High-Grade Serous Ovarian Cancer

This is an open label Phase II study of anti-PD1 antibody pembrolizumab, in combination with anlotnib in patients with recurrent platinum sensitive, resistant or refractory. The study will enroll approximately 40 evaluable patients in total. Accrual is expected to take 18 months. Disease Evaluation: CT at Baseline, after 3rd cycle, after 6th cycle then, after every 6th cycle (or sooner if disease progression) Adverse Events: Day 1 of each cycle, end of treatment, safety follow-up. Hematology: Baseline, Day 1 of each cycle, end of treatment, safety follow-up . Chemistry: Baseline, Day 1 of each cycle, end of treatment, safety follow-up Performance Status: Baseline, Day 1 of each cycle, end of treatment, post treatment evaluations Full Physical Examination (including basic neurological examination, vital signs, and body weight): Baseline, Day 1 Cycle 1, Day 1 of every 3rd cycle, end of treatment, post treatment evaluations Directed Physical Examination (including basic neurological exam, vital signs, and body weight): On cycles not requiring a full physical examination (e.g. cycles 2 and 3, cycles 5 and 6) Vital Signs: Baseline, Day 1 of each cycle, end of treatment evaluations Pregnancy test: Within 72 hours prior to receiving first dose of study treatment in patients of childbearing potential post treatment PT/INR and APTT: Baseline, Cycle 6 Day 1, Cycle 12 Day 1, end of treatment, safety follow-up. Urinalysis: Baseline, Cycle 1Day 1, every 2nd cycle after Cycle 1, end of treatment. UPCR Ratio: Baseline, Cycle 1Day 1 and, Day 1 of every 2nd cycle. T3, FT4, and TSH: Baseline, Cycle 3 Day 1 then Day 1 of every 3rd cycle, end of treatment, safety follow-up Tissue Biopsy: Baseline, 2-3 weeks after Cycle 3, end of treatment (optional) Blood Collection (correlative studies): Baseline (within 2 weeks prior to treatment initiation), Cycle 2 - Day 1, Cycle 4- Day 1, Cycle 7- Day 1, Cycle 10 -Day 1, and at the end of study treatment or at time of discontinuation (within two weeks after the last treatment cycle is completed) or, at the time of disease progression or for any other reason that requires study treatment termination, whichever occurs sooner. On those patients, who have already completed 10 cycles, the one additional correlative blood sample will be collected at the time of their next cycle. Safety Analysis: The frequency of toxicities will be tabulated by grade across all dose levels and cycles. Toxicity rates will be estimated using 90% confidence intervals, which will be obtained using Jeffreys prior method. All participants who receive any study treatment will be considered evaluable for toxicity. The overall and progression free survival will be summarized using standard Kaplan-Meier methods, with estimates of median survival and given survival rates will be obtained with 90% confidence intervals. Efficacy Analysis: The overall and progression free survival will be summarized using standard Kaplan-Meier methods, with estimates of median survival and given survival rates will be obtained with 90% confidence intervals. Objective tumor response will be tabulated for all patients that completed at least three cycles of the proposed treatment Correlative Data Analysis: The blood and tumor samples will be collected as biomarkers and will be reported using the appropriate descriptive statistics depending on clinical outcome. Associations between these markers and PFS will be evaluated using Cox regression models; while associations with tumor response will be evaluated using logistic regression models.