P1.01-76 Randomized Phase II Study of Immunotherapy With or Without Low Dose Chemotherapy for Patients with Performance Status of 2

Abstract

Combination chemo-immunotherapy has become a standard of care for patients with non-small cell lung cancer (NSCLC) who have performance status (PS) of 0-1. Limited information is available regarding optimal immunotherapy treatment options for patients with PS 2. In the current study, we examined the clinical and immunologic effects of immunotherapy alone or in combination with low dose carboplatin and paclitaxel as a potential treatment option for the PS 2 population. This randomized phase II study will enroll 40 patients total with 1:1 randomization to pembrolizumab 200 mg day 1 every 3 weeks or pembrolizumab 200 mg day 1 with carboplatin AUC 1 and paclitaxel 25 mg/m2 days 1, 8, and 15 every 3 weeks. At the time abstract preparation, 36 evaluable patients have been enrolled with 28 patients having completed response evaluation. Blood for circulating immune cell phenotyping, soluble program death ligand 1 (sPD-L1), and immune-modulatory miRs was collected prior to treatment and at weeks 4 and 7. Investigator assessed irRECIST responses were examined at week 8 and every 12 weeks thereafter. Responses have been observed in 6 out of 16 patients (38%) in the control arm and 7 out of 12 patients (58%) in the experimental arm. Treatment related adverse events have been similar between the two arms with increases in infusion reactions in patients receiving low-dose carboplatin and paclitaxel. Interim biomarker analyses indicate circulating myeloid derived suppressor cells numbers decreased in patients receiving pembrolizumab combined with carboplatin and paclitaxel but not in patients receiving pembrolizumab alone. Accrual is expected to complete soon with updated response rates and progression free survival are anticipated to be mature and will be presented at the time of the meeting. The combination of pembrolizumab with low-dose weekly carboplatin and paclitaxel is well-tolerated and active in the PS 2 population. Comparison of this regimen to pembrolizumab alone will be performed once data have matured.