Reference: August 2025 | Issue 8 | Vol 11 | Page 6
Results from a global phase 3 clinical trial found that maintenance therapy with a combination of lurbinectedin and atezolizumab helped some patients with extensive-stage small cell lung cancer (ES-SCLC) live longer compared to maintenance therapy with atezolizumab alone.
The IMforte trial included 660 patients with previously untreated ES-SCLC, no history of metastases to the brain or spinal cord, and good performance status. Participants were enrolled at 91 study sites in 13 different countries.
All patients enrolled in the study received standard of care induction therapy of atezolizumab, carboplatin, and etoposide in four cycles. After induction therapy, patients were eligible to continue in the study if they had an ongoing tumour response or stable disease after four cycles. A total of 483 patients went on to receive maintenance therapy, either lurbinectedin and atezolizumab (n=242) or atezolizumab alone (n=241).
After a median follow-up of 15 months, the median progression-free survival (PFS) was 5.4 months in the lurbinectedin and atezolizumab arm versus 2.1 months in the atezolizumab alone arm. Patients treated with lurbinectedin and atezolizumab had a 46 per cent lower risk of cancer progression than those treated with atezolizumab alone. The median overall survival was 13.2 months with the combination and 10.6 months with atezolizumab monotherapy. Patients treated with lurbinectedin and atezolizumab had a 27 per cent lower risk of death.
There was a noted difference in adverse events between the two groups. Treatment-related adverse events (TRAE) occurred in 83.5 per cent of patients in the combination arm, compared to 40 per cent in the atezolizumab alone arm. In the lurbinectedin and atezolizumab arm, 25.6 per cent of patients experienced a grade ≥3 adverse event and 0.8 per cent experienced a grade 5 adverse event.
In the atezolizumab alone arm, 5.8 per cent experienced a grade ≥3 adverse event and 0.4 per cent experienced a grade 5 adverse event. In the combination arm, 6.2 per cent of patients discontinued treatment due to side effects compared to 3.3 per cent in the atezolizumab alone arm.
Commenting on the study, lead author, Luis Paz Ares, from 12 de Octubre University Hospital in Madrid, Spain, said: “While the introduction of immunotherapy in first-line treatment has improved outcomes, advanced small cell lung cancer remains difficult to treat.
“The phase 3 IMforte trial shows that the new treatment combination of lurbinectedin and atezolizumab given as maintenance therapy after first-line treatment helps people live longer and reduces the risk of disease progression or death. This outcome represents a major milestone and could provide a much-needed option for advancing the treatment of this aggressive disease.”
Reference
Paz-Ares L, Borghaei H, Liu S, et al. Lurbinectedin (lurbi) + atezolizumab (atezo) as first-line (1L) maintenance treatment (tx) in patients (pts) with extensive-stage small cell lung cancer (ES-SCLC): Primary results of the phase 3 IMforte trial. Abstract #8006. American Society of Clinical Oncology Annual Meeting. May 30-June 3, 2025. Chicago, US.
