1171MO PACIFIC-R real-world study: Treatment duration and interim analysis of progression-free survival in unresectable stage III NSCLC patients treated with durvalumab after chemoradiotherapy

Abstract

Durvalumab consolidation therapy for up to 12 months (PACIFIC regimen) is now standard of care in patients (pts) with unresectable Stage III non-small-cell lung cancer (NSCLC) without disease progression after platinum-based chemoradiotherapy (CRT). PACIFIC-R assesses the effectiveness of durvalumab in this pt population in a real-life setting. PACIFIC-R (NCT03798535) is a large international, observational study in pts who received ≥1 dose of durvalumab (10 mg/kg Q2W) as part of an AstraZeneca-initiated expanded access program. Pts had completed platinum-based chemotherapy concurrent or sequential to radiotherapy within the previous 12 weeks without evidence of disease progression. Outcomes were assessed in the full analysis set (N=1155). Median time to durvalumab initiation after the end of RT was 52 days. Overall median durvalumab treatment duration was 337 days (11 months); 232 (20.1%) pts received treatment for >12 months (50 [4.3%] for >14 months). Pts received a median of 22 infusions. Reasons for/median time to treatment discontinuation included completion of treatment (47.6%/11.8 months; investigator decision per country protocol), disease progression (25.8%/5.1 months) and adverse event (AE; 17.5%/2.8 months). Pneumonitis was the most common AE leading to discontinuation (temporary: 5.1%; permanent: 8.7%). 214 (18.5%) pts had any-grade pneumonitis and/or interstitial lung disease (median time from durvalumab start: 74 days [2.4 months]). Of these, most events were moderate (8.8%) in severity; 2 (0.2%) and 1 (0.1%) pts had a life-threatening or fatal event, respectively. Interim analysis (51.8% of events) showed a median real-world PFS (rwPFS) of 22.5 months (95% CI, 19.7–25.5). rwPFS by baseline PD-L1 status and prior CRT will be included in the final presentation. These results demonstrate the effectiveness of consolidation durvalumab after CRT in a real-world cohort of pts with unresectable Stage III NSCLC; pneumonitis events were mostly moderate in severity. Additional data from an externally sponsored study with similar enrolment criteria in Spain will be included in the final presentation.