Key takeaways
Tecentriq plus Zepzelca significantly improved both PFS and OS in ES-SCLC maintenance therapy versus Tecentriq alone.
IMforte's design showcases the value of seamless transition from induction to maintenance therapy in advanced lung cancer.
The study reinforces the importance of robust global trial infrastructure to execute large, multi-phase oncology protocols efficiently.
Genentech has shared positive data from a Tecentriq (atezolizumab) and Zepzelca (lurbinectedin) combination therapy for the first-line treatment of patients with extensive-stage small cell lung cancer (ES-SCLC) following induction therapy with carboplatin, etoposide, and Tecentriq. These new data are being presented at the 2025 American Society of Clinical Oncology (ASCO) Annual Meeting, as well as published in The Lancet.1
Promising Phase III IMforte trial results for ES-SCLC
In the Phase III IMforte clinical trial (NCT05091567), the combination therapy reduced the risk of disease progression or death by 46% and the risk of death by 27% compared to Tecentriq maintenance therapy alone. Safety in the study was consistent with the known profiles of both Tecentriq and Zepzelca.
In a press release, Luis Paz-Ares, MD, PhD, head of medical oncology at the Hospital Universitario 12 de Octubre in Madrid, Spain, and IMforte trial principal investigator, said: “Small cell lung cancer is an aggressive and devastating disease. At the time of diagnosis, the large majority of patients have already progressed to extensive-stage disease and only one out of five survive longer than two years. The IMforte results are very encouraging showing a potentially practice-changing option that could improve survival for patients with a very high unmet need.”
Tecentriq and Zepzelca show survival advantage over Tecentriq alone
The IMforte study had patients first complete four cycles of Tecentriq combined with chemotherapy over approximately three months prior to randomization for maintenance treatment. From the point of randomization, the Tecentriq-Zepzelca combination demonstrated a median overall survival (OS) of 13.2 months versus 10.6 months for Tecentriq alone.
Additionally, median progression-free survival (PFS) by independent assessment was 5.4 months for the combination regimen versus 2.1 months for Tecentriq alone. There were no new safety signals observed in the trial.
Study design supports new maintenance standard for small cell lung cancer
In the press release, Levi Garraway, MD, PhD, Genentech’s chief medical officer and head of global product development, added: “In the IMforte study, the Tecentriq and lurbinectedin maintenance regimen significantly extended survival for people living with extensive-stage small cell lung cancer. This study builds on Tecentriq’s well-established safety and efficacy profile as the first immunotherapy for this cancer type and may provide another approach to help physicians and patients better manage this aggressive disease.”
IMforte is a Phase III, open-label, randomized trial. In the study, patients first received Tecentriq with carboplatin and etoposide as induction therapy for four 21-day cycles. Those without disease progression were randomized 1:1 in the next portion of the study to receive maintenance therapy with either the Tecentriq-Zepzelca combination or Tecentriq alone until disease progression or unacceptable toxicity.
A total of 660 patients were enrolled into the induction portion of the study and 483 were randomized in the maintenance phase. The primary endpoints were independent review facility-assessed PFS and OS from randomization into the maintenance phase.
Ongoing research expands Tecentriq’s role in SCLC maintenance therapy
Tecentriq is also being evaluated alongside Reqorsa (quaratusugene ozeplasmid) as a combination maintenance therapy for the treatment of ES-SCLC. Earlier in January, Genprex announced the first patient had been dosed in the Phase II expansion portion of its Acclaim-3 study (NCT05703971) evaluating the Tecentriq-Reqorsa combination.2
This expansion portion of the open-label, multi-center Acclaim-3 trial expects to enroll 50 patients across 10-15 sites in the US. The primary endpoint is to determine the 18-week PFS rate from the time of the start of maintenance therapy with Reqorsa and Tecentriq. Patients will be treated with the combination regimen until disease progression or unacceptable toxicity is experienced. Once the 25th patient is enrolled, treated, and reaches 18 weeks of follow up, an interim analysis, expected in the second half of 2025, will be performed.
References
1. Genentech’s Tecentriq Combined with Lurbinectedin Shows Significant Survival Benefit in Extensive-Stage Small Cell Lung Cancer. News release. Genentech. June 2, 2025. Accessed June 3, 2025. https://www.businesswire.com/news/home/20250602872233/en/Genentechs-Tecentriq-Combined-with-Lurbinectedin-Shows-Significant-Survival-Benefit-in-Extensive-Stage-Small-Cell-Lung-Cancer
2. First Patient Dosed in Phase II Expansion Portion of Acclaim-3 Trial of Reqorsa in Combination With Tecentriq. Applied Clinical Trials. January 23, 2025. Accessed June 3, 2025. https://www.appliedclinicaltrialsonline.com/view/first-patient-dosed-phaseii-expansion-acclaim3-trial-reqorsa-tecentriq