Jazz Pharmaceuticals + PharmaMar announce results of ATLANTIS phase III study of Zepzelca + doxorubicin for small cell lung cancer.

Jazz Pharmaceuticals plc along with its partner, PharmaMar announced results from the ATLANTIS Phase III multicenter, randomized, controlled study evaluating Zepzelca (lurbinectedin) in combination with doxorubicin versus physician's choice of topotecan or cyclophosphamide/doxorubicin/vincristine (CAV) for adult patients with small cell lung cancer (SCLC) whose disease progressed following one prior platinum-containing line. Patients received lurbinectedin at 2.0mg/m2 in the combination arm, which is lower than the FDA approved dose of Zepzelca at 3.2mg/m2. The study did not meet the pre-specified criteria of significance for the primary endpoint of overall survival (OS) in the intent-to-treat (ITT) population comparing lurbinectedin in combination with doxorubicin to the control arm, though there was no adverse effect on OS with the experimental arm. Based on the study design, no additional hypotheses were formally tested. Importantly, key secondary and subgroup analyses favored the lurbinectedin combination arm. Lurbinectedin monotherapy was not tested in ATLANTIS. The safety data in this study was consistent with the known safety profile of lurbinectedin monotherapy with no new safety signals observed. The experimental arm showed favorable safety and tolerability with regard to Grade-3 or greater drug related adverse events (AEs), deaths due to AEs, hematologic toxicity, dose reductions and treatment discontinuations due to AEs, compared to the control arm. The FDA approved Zepzelca under accelerated approval in June 2020 for the treatment of adult patients with metastatic SCLC with disease progression on or after platinum-based chemotherapy. The approval is based on ORR and duration of response demonstrated in an open-label, monotherapy clinical study. The companies will provide the ATLANTIS data to FDA and look forward to working with the agency to determine the confirmatory data that is needed for full approval.