How effective is lurbinectedin compared to standard chemo?
Lurbinectedin (Zepzelca), approved for relapsed small cell lung cancer (SCLC) after platinum chemotherapy, showed noninferior overall survival to the standard topotecan regimen in the phase 3 ATLANTIS trial. Median overall survival was 9.3 months with lurbinectedin plus irinotecan versus 8.6 months with topotecan (HR 0.95, 95% CI 0.83-1.10; p=0.17 for noninferiority).[1][2] Progression-free survival was similar at 4.8 months versus 4.1 months (HR 0.92).[1]
Patients on lurbinectedin reported better quality of life, with less worsening in physical functioning and fewer severe hematologic toxicities like anemia and neutropenia compared to topotecan.[2][3]
What were the response rates in the ATLANTIS trial?
Overall response rate was 22% for lurbinectedin/irinotecan (complete response 4%) versus 17% for topotecan (complete response 1%). Median duration of response was 4.5 months versus 3.3 months.[1][2]
How does lurbinectedin perform as monotherapy?
In the earlier phase 2b trial supporting FDA approval, single-agent lurbinectedin achieved a 35% overall response rate in sensitive relapsed SCLC (median duration 5.3 months) and 22% in resistant cases.[4] This outperformed historical topotecan monotherapy rates of 15-24%.[5]
Why do some patients prefer lurbinectedin over topotecan?
Topotecan causes more grade 3/4 adverse events (febrile neutropenia 25% vs 8%; anemia 51% vs 22%). Lurbinectedin monotherapy has myelosuppression but lower rates of severe fatigue and nausea.[3][6] Real-world data confirm better tolerability, with fewer dose reductions.[7]
When is lurbinectedin used instead of chemo standards?
It's standard for platinum-sensitive relapsed SCLC after immunotherapy, per NCCN guidelines, as second- or third-line therapy. Topotecan remains an option for resistant disease or when lurbinectedin is unavailable.[8]
Are there ongoing trials comparing it to other treatments?
Phase 3 trials test lurbinectedin with atezolizumab (IMforte) or doxorubicin (LAGOON) in frontline and relapsed SCLC, aiming to improve on chemo-alone benchmarks.[9]
[1]: JAMA Oncology - ATLANTIS trial
[2]: ESMO 2023 presentation
[3]: FDA approval summary
[4]: Lancet Oncology - phase 2b
[5]: Annals of Oncology - topotecan meta-analysis
[6]: Supportive Care in Cancer - toxicity comparison
[7]: Lung Cancer - real-world Zepzelca
[8]: NCCN SCLC guidelines v2.2024
[9]: ClinicalTrials.gov - IMforte (NCT04787991), LAGOON (NCT05164169)