Comparative Effectiveness of Lurbinectedin for the Treatment of Relapsed Small Cell Lung Cancer in the Post-Platinum Setting: A Real-World Canadian Synthetic Control Arm Analysis.

Background: Based on findings from a single-arm, phase 2 basket trial (NCT02454972), lurbinectedin may be an effective treatment for individuals with small cell lung cancer (SCLC) who progressed on or after platinum-based chemotherapy.

Objective: To estimate the comparative effectiveness of lurbinectedin versus the historical standard of care for relapsed SCLC in Canada.

Methods: A synthetic control arm (SCA) analysis was conducted using real-world data. Population-level data were obtained from real-world databases in Alberta, Canada. Individuals diagnosed with SCLC who initiated post-platinum systemic therapy and met approximated eligibility criteria from the lurbinectedin trial were included in the SCA. Median overall survival (OS) in the SCA was estimated after adjusting for chemotherapy-free interval (CTFI; < 90 versus ≥ 90 days) and stage at initial diagnosis (extensive versus limited). The CTFI-adjusted hazard ratio was estimated using a Cox proportional hazards model.

Results: One hundred seventy-four individuals were included in the SCA and 105 in the lurbinectedin trial. The adjusted median OS in the SCA was 6.1 months (95% CI 5.4-7.7 months; unadjusted: 6.7 months, 95% CI 6.0-7.7 months) versus 9.3 months (95% CI 6.3-11.8 months) in the lurbinectedin trial. The adjusted hazard ratio comparing lurbinectedin with the historical standard of care (referent group) was 0.61 (95% CI 0.45-0.82; unadjusted HR: 0.72; 95% CI 0.54-0.97). The hazard ratio was more pronounced among individuals with CTFI ≥ 90 days (HR: 0.49, 95% CI 0.33-0.73).

Conclusion: These findings suggest improved OS with lurbinectedin monotherapy versus the historical standard of care in Alberta, Canada.