Safety and feasibility of consolidation pembrolizumab following concurrent chemoradiation for unresectable stage III non-small cell lung cancer: Hoosier Cancer Research Network LUN14-179.
8523 Background: The standard of care for unresectable stage III NSCLC is concurrent chemorad. Following treatment, the risk of radiation pneumonitis is greatest at 1-3 mo. Pneumonitis risk increases with consolidation chemotherapy. A previous trial by our group (Hanna et al, JCO 2008) of consolidation docetaxel showed 80.8% completed 3 planned cycles of chemo with a grade 3-5 pneumonitis rate of 9.6% and 1 death. PD-1 inhibitors are also associated with an increased risk of pneumonitis in the metastatic setting. We conducted a phase II trial of consolidation pembro initiated 1-2 mo after concurrent chemorad, a period during which pts are at high risk of developing pneumonitis. Methods: Pts with stage III NSCLC who completed chemorad with either carbo/paclitaxel, cis/etop, or cis/pemetrexed plus 59-66.6 Gy of radiation and had no PD received pembro 200mg IV q3wk for up to 1 yr. Primary endpoint is time to metastatic disease. The objective of the study is to evaluate both safety and efficacy, and here we report preliminary safety and feasibility results. Evaluable pts for this analysis had ≥3 mo of f/u or went off study due to PD, toxicity, or death < 3 mos after initiation of pembro. Results: 93 pts enrolled. Median age 67 (range 46-84), 59 (63.4%) were male. 87 (93.5%) were former or current smokers. 68 (73.1%) received carbo/pac, 24 (25.8%) received cis/etop, and 1 received cis/pemetrexed. SqCC (n = 41), non-SqCC (n = 43), NSCLC NOS (n = 8), mixed (n = 1). IIIA (n = 56), IIIB (n = 37). At the time of analysis, 83 of 93 pts were evaluable. 66 of 83 (79.5%) received ≥ 3 mo of pembro. 17 (20.5%) pts developed any grade pneumonitis with 14 of 17 occurring in the first 12 wks (median 9 wks). Only 3 (3.6%) pts developed grade 3-5 pneumonitis related to pembro. There was 1 pneumonitis-related death and a second death from respiratory failure possibly related to pembro. Conclusions: This early report indicates that most patients can safely receive consolidation pembro within 1-2 mo of completing chemorad. The incidence of serious pneumonitis during the first 3 mo of treatment appears low. Updated safety data on all 93 pts will be presented at the ASCO meeting. Clinical trial information: NCT02343952.