Jazz Pharmaceuticals Announces Phase 3 IMforte Trial Results Showing Zepzelca Plus Atezolizumab First-Line Maintenance Therapy Reduces Disease Progression Risk By 46% And Extends Median Overall Survival To 13.2 Months In ES-SCLC; Data Presented At ASCO 2025 And Published In The Lancet, Supporting New Standard Of Care And FDA sNDA Submission

First-line maintenance combination therapy reduced the risk of disease progression or death by 46%, with a median overall survival of 13.2 months vs 10.6 months for atezolizumab alone from the point of randomization

First Phase 3 study to demonstrate statistically significant and clinically meaningful improvements in both progression-free and overall survival in ES-SCLC first-line maintenance

Results presented at the ASCO 2025 Annual Meeting and simultaneously published in The Lancet

Jazz to host investor webcast on Tuesday, June 10 to review Zepzelca data

For U.S. media and investors only

DUBLIN, June 2, 2025 /PRNewswire/ -- Jazz Pharmaceuticals plc (NASDAQ:JAZZ) today announced positive results from the Phase 3 IMforte study of Zepzelca® (lurbinectedin) in combination with atezolizumab (Tecentriq®) as a first-line maintenance treatment for people with extensive-stage small cell lung cancer (ES-SCLC), following induction therapy with carboplatin, etoposide and atezolizumab. The study met both primary endpoints, demonstrating statistically significant improvements in progression-free survival (PFS) and overall survival (OS) compared to atezolizumab alone.

IMforte is the first global Phase 3 trial to demonstrate clinically meaningful PFS and OS benefits in the first-line maintenance setting for ES-SCLC and supports maintenance therapy with Zepzelca plus atezolizumab as a new standard of care for patients. The data were presented today in an oral session at the 2025 American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago and published simultaneously in The Lancet. Data from the trial served as the basis for the supplemental New Drug Application (sNDA) submission to the U.S. Food and Drug Administration (FDA).

Following induction therapy with carboplatin, etoposide and atezolizumab, patients who did not have disease progression were randomized to receive Zepzelca plus atezolizumab or atezolizumab alone. From the point of randomization, the median PFS was 5.4 months for the Zepzelca plus atezolizumab combination versus 2.1 months for atezolizumab alone (stratified HR = 0.54, 95% CI: 0.43–0.67; p < 0.0001), and median OS was 13.2 months versus 10.6 months (stratified hazard ratio [HR] = 0.73; 95% CI: 0.57–0.95; p = 0.0174). The combination reduced the risk of disease progression or death by 46% and the risk of death by 27% compared to atezolizumab alone. The Zepzelca plus atezolizumab combination had no new or unexpected safety signals.