Paclitaxel, Pembrolizumab and Olaparib in Previously Treated Advanced Gastric Adenocarcinoma

"1. Patients will receive treatment on Day 1 and 8 starting with cycle 2.~2. Paclitaxel (80 mg) will be administered IV on days 1 and 8 starting with cycle 2 (every 21 days).~3. Drug - Paclitaxel - 80mg IV"

"1. Olaparib will be taken by mouth daily for 3 weeks (every 21 days).~2. Drug - 100 mg or 300mg"

"1. Patients will receive treatment every 21 days.~2. Pembrolizumab (200 mg) will be administered IV on day 1 (every 21 days).~3. Drug - 200mg IV"