Between 13% and 15% of lung cancer diagnoses are SCLC, the most aggressive type of lung cancer. About 70% of people are diagnosed when SCLC has already spread beyond its site of origin. Advances in treatment for extensive-stage SCLC since 2019 have improved outcomes, but it remains difficult to treat, and the five-year relative survival rate is 3%, with a median survival time of 1 year. Current treatment plans include a combined immunotherapy and chemotherapy approach with patients being on maintenance with immunotherapy thereafter. The immunotherapy notably used is TECENTRIQ (atezolizumab). ZEPZELCA (lurbinectedin), a drug approved for use in the treatment of SCLC, is an alkylating agent with a mechanism of action whereby it damages the DNA of cancer cells to hinder proliferation.

Findings from the Phase III IMforte trial, presented at the ASCO Annual Meeting, showed that previously treated patients who received a combined maintenance therapy of ZEPZELCA and TECENTRIQ lived months longer than those on TECENTRIQ alone.  Patients in the IMforte study first completed four cycles of TECENTRIQ combined with chemotherapy, over the course of approximately three months, before being randomized into maintenance treatment. From the point of randomization, the median Overall Survival (OS) for the TECENTRIQ plus ZEPZELCA regimen was 13.2 months versus 10.6 months for TECENTRIQ alone. Median Progression-free Survival (PFS) by independent assessment was 5.4 months versus 2.1 months, respectively. No new safety signals were observed.

KOL insights

“Immunotherapy has improved survival outcomes for patients with extensive-stage SCLC, marking meaningful progress in a historically challenging disease. However, despite these advances, long-term outcomes remain suboptimal, underscoring the need for better strategies. The integration of lurbinectedin—a novel DNA-damaging agent—into the maintenance setting alongside atezolizumab following initial chemoimmunotherapy represents an important next step. This approach offers a way to extend disease control and may signal a shift toward more durable benefit for patients.” – Expert Opinion

Conclusion

The encouraging data not only support the role of this combination as a new first-line maintenance standard for ES-SCLC but also pave the way for strategic regulatory and commercial advances. In May 2025, PharmaMar submitted a Marketing Authorization Application (MAA) to the European Medicines Agency (EMA) for the ZEPZELCA plus TECENTRIQ combination in adult patients whose disease has not progressed after induction therapy with TECENTRIQ, carboplatin, and etoposide. For Roche, the results represent a successful step toward strengthening TECENTRIQ’s standing in a competitive immunotherapy market, particularly against AstraZeneca’s IMFINZI. For Jazz Pharmaceuticals and PharmaMar, the trial could shift ZEPZELCA from its current post-chemotherapy indication into the first-line setting, potentially converting its existing accelerated approval into a full regulatory endorsement. While the IMforte success establishes a new benchmark, it also sets the stage for future innovation to build upon these gains and further improve outcomes in this aggressive cancer type.