A Phase III, Open-Label Study of Maintenance Lurbinectedin in Combination With Atezolizumab Compared With Atezolizumab in Participants With Extensive-Stage Small-Cell Lung Cancer

Summary

Study GO43104 is a Phase III, randomized, open-label, multicenter study of lurbinectedin in combination with atezolizumab compared with atezolizumab alone administered as maintenance therapy in participants with extensive-stage small-cell lung cancer (ES-SCLC) after first-line induction therapy with carboplatin, etoposide, and atezolizumab. The study consists of 2 phases: an induction phase and a maintenance phase. Participants need to have an ongoing response or stable disease per the Response Evaluation Criteria in Solid Tumor (RECIST) v1.1 criteria after completion of 4 cycles of carboplatin, etoposide, and atezolizumab induction treatment in order to be considered for eligibility screening for the maintenance phase. Eligible participants will be randomized in a 1:1 ratio to receive either lurbinectedin plus atezolizumab or atezolizumab in the maintenance phase.

Timeline

Start

2021-11-18

Primary completion

2024-07-29

Completion

2028-02-28

Outcome

Met primary endpoint

registry MEDIAN Atezolizumab: 2.14 (95% Confidence Interval 1.64) months MEDIAN Atezolizumab+ Lurbinectedin: 5.36 (95% Confidence Interval 4.24) months NCT05091567 ↗

registry analysis (superiority test); Atezolizumab vs Atezolizumab+ Lurbinectedin; p < .0001; Hazard Ratio (HR) 0.54 (95% CI 0.43 to 0.67); Log Rank NCT05091567 ↗

registry MEDIAN Atezolizumab: 10.64 (95% Confidence Interval 9.49) months MEDIAN Atezolizumab+ Lurbinectedin: 13.24 (95% Confidence Interval 11.89) months NCT05091567 ↗

registry analysis (superiority test); Atezolizumab vs Atezolizumab+ Lurbinectedin; p = 0.0174; Hazard Ratio (HR) 0.73 (95% CI 0.57 to 0.95); Log Rank NCT05091567 ↗

release “demonstrated a statistically significant improvement in the primary endpoints of overall survival (OS) and progression-free survival (PFS)” jazzpharma.com ↗

release “The sNDA submission is based on results from the Phase 3 IMforte trial of Zepzelca in combination with atezolizumab, which met both primary endpoints” jazzpharma.com ↗

release “Phase 3 IMforte trial ( NCT05091567 ), which showed that the Zepzelca and atezolizumab combination reduced the risk of disease progression or death by 46%” jazzpharma.com ↗

release “Median progression-free survival (PFS) by independent assessment was 5.4 months versus 2.1 months, respectively (stratified HR=0.54, 95% CI: 0.43–0.67; p<0.0001).” jazzpharma.com ↗

Publications

• Paz-Ares L, Borghaei H, Liu SV, Peters S, Herbst RS, Stencel K, Majem M, Sendur MAN, Czyzewicz G, Caro RB, Lee KH, Johnson ML, Karadurmus N, Grohe C, Baka S, Csoszi T, Ahn JS, Califano R, Yang TY, Kemal Y, Ballinger M, Cuchelkar V, Graupner V, Lin YC, Chakrabarti D, Bhatt K, Cai G, Iannone R, Reck M; IMforte investigators. Efficacy and safety of first-line maintenance therapy with lurbinectedin plus atezolizumab in extensive-stage small-cell lung cancer (IMforte): a randomised, multicentre, open-label, phase 3 trial. Lancet. 2025 Jun 14;405(10495):2129-2143. doi: 10.1016/S0140-6736(25)01011-6. Epub 2025 Jun 2.

Drugs

Evaluation	Drug	Modality	Dose	Route
Subject	Atezolizumab	Monoclonal antibody	1200 mg	Intravenous
Subject	Lurbinectedin	Other / unclassified	3.2 mg/m2	Intravenous
Background	Carboplatin	Small molecule	—	—
Background	Etoposide	Small molecule	—	—

Indications