OA20.01 Long Term Survival in Operable Stage Iiia Nsclc Patients Treated With Neoadjuvant Nivolumab Plus Chemotherapy - Nadim Study

Introduction: Neoadjuvant chemoimmunotherapy been shown to be highly effective in resectable stage IIIA NSCLC. Now we provide long term survival data Methods: This was an open-label, multicentre, single-arm phase 2 trial in which patients with histologically or cytologically documented stage IIIA NSCLC and Eastern Cooperative Oncology Group performance status of 0 or 1 and who were deemed locally to be surgically resectable by a multidisciplinary clinical team were treated with neoadjuvant intravenous paclitaxel (200 mg/m2) and carboplatin (area under curve 6;6 mg/mL per min) plus nivolumab (360 mg) on day 1 of each 21-day cycle, for three cycles before surgical resection, followed by adjuvant intravenous nivolumab monotherapy for 1 year (240 mg every 2 weeks for 4 months, followed by 480 mg every 4 weeks for 8 months). Here we report progression-free survival (PFS) and Overall survival (OS) at 36 and 42 months, assessed in the modified intention-to-treat population (ITT), which included all patients who received neoadjuvant treatment, and in the per-protocol population (PP), which included all patients who had tumour resection and received at least one cycle of adjuvant treatment. Results: Median follow-up time was 37.9 months (95%CI: 36.7-40.7), with a 94% maturity at 36 months. Among the ITT population (N=46), 37 patients, constituting the PP population, received subsequent adjuvant therapy. Of them, 27 (58.7%) patients completed the adjuvant treatment (16 cycles), 10 (21.7%) patients received between 3 and 15 cycles of adjuvant therapy, and 9 (19.6%) patients did not receive adjuvant therapy. At the time of data cutoff (March 2021), progression disease was diagnosed in 14 patients and 9 deaths were recorded in the ITT population. Of these, three deaths corresponded to patients who did not undergo surgery and had disease progression, four deaths corresponded to patients who underwent surgery and had disease progression, and the two remaining deaths corresponded to patients who were diagnosed as being disease free but died from COVID19 infection. Notably, among patients who could not undergo surgery (N=5), one of them is still alive and with no evidence of disease. PFS at 36 and 42 months in the ITT population were 69.6% (95%CI: 54.1-80.7), in both cases. Similarly, PFS at 36 and 42 in the PP population were 81.1% (95%CI: 64.4-90.5) in both cases. The percentage of patients who were alive at 36 and 42 months in the modified ITT population were 81.86% (95% CI: 66.8-90.6) and 78.94% (95%CI: 63.1-88.6), respectively. Likewise, OS at 36 and 42 months in the PP population was 91.0% (95%CI: 74.2-97.0) and 87.3% (95%CI: 69.3-95.1), respectively. Conclusion: The efficacy of nivolumab in combination with platinum-based chemotherapy in patients with resectable stage IIIA NSCLC is clearly supported by long term survival data. Keywords: NADIM trial, neoadjuvant chemo-therapy, long term survival