Randomized Phase 2 Studies of Checkpoint Inhibitors Alone or in Combination With Pegilodecakin in Patients With Metastatic NSCLC (CYPRESS 1 and CYPRESS 2)

Introduction: Checkpoint inhibitors (CPIs) have been approved to treat metastatic NSCLC. Pegilodecakin + CPI suggested promising efficacy in phase 1 IVY, providing rationale for randomized phase 2 trials CYPRESS 1 and CYPRESS 2.

Methods: CYPRESS 1 (N = 101) and CYPRESS 2 (N = 52) included Eastern Cooperative Oncology Group performance status of 0 to 1 and first-line/second-line metastatic NSCLC, respectively, without known EGFR/ALK mutations. Patients were randomized 1:1; control arms received pembrolizumab (CYPRESS 1) or nivolumab (CYPRESS 2); experimental arms received pegilodecakin + CPI. Patients had programmed death-ligand 1 tumor proportion score of greater than or equal to 50% (CYPRESS 1) or 0% to 49% (CYPRESS 2). Primary end point was objective response rate (ORR) per investigator. Secondary end points included progression-free survival (PFS), overall survival (OS), and safety. Exploratory end points included immune activation biomarkers.

Results: Median follow-up for CYPRESS 1 and CYPRESS 2 was 10.0 and 11.6 months, respectively. Results for pegilodecakin + pembrolizumab versus pembrolizumab were as follows: ORR per investigator 47% versus 44% (OR = 1.1, 95% confidence interval [CI]: 0.5-2.5); median PFS 6.3 versus 6.1 months (hazard ratio [HR] = 0.937, 95% CI: 0.54-1.625); and median OS 16.3 months versus not reached (HR = 1.507, 95% CI: 0.708-3.209). Results per blinded independent central review were consistent. Treatment discontinuation rate owing to adverse events (AEs) doubled in the experimental arm (32% versus 15%). AEs with grade greater than or equal to 3 treatment-related AEs (62% versus 19%) included anemia (20% versus 0%) and thrombocytopenia (12% versus 2%). Results for pegilodecakin + nivolumab versus nivolumab were as follows: ORR per investigator 15% versus 12% (OR = 1.2, 95% CI: 0.3-5.9); median PFS 1.9 versus 1.9 months (HR = 1.006, 95% CI: 0.519-1.951); and median OS 6.7 versus 10.7 months (HR = 1.871, 95% CI: 0.772-4.532). AEs with grade greater than or equal to 3 treatment-related AEs (70.4% versus 16.7%) included anemia (40.7% versus 0%), fatigue (18% versus 0%), and thrombocytopenia (14.8% versus 0%). Biomarker data suggested activation of immunostimulatory signals of interleukin-10R pathway in pegilodecakin-containing arms.

Conclusions: Despite evidence of biological effect in peripheral blood, adding pegilodecakin to CPI did not improve ORR, PFS, or OS, in first-line/second-line NSCLC. Pegilodecakin + CPI has been found to have overall higher toxicity compared with CPI alone, leading to doubling of treatment discontinuation rate owing to AEs.