FDA Approves Cemiplimab Plus Chemotherapy as First-line NSCLC Treatment

The PD-L1 inhibitor cemiplimab was approved in combination with platinum-based chemotherapy for the first-line treatment of adult patients with advanced non–small cell lung cancer (NSCLC) with no EGFR, ALK or ROS1 aberrations, its drugmaker said Tuesday.

The pivotal trial leading to the approval had been stopped early based on a recommendation by the independent data monitoring committee after the combination demonstrated a significant improvement in overall survival (OS), the primary end point.

Patients must either have metastatic or locally advanced tumors that are not candidates for surgical resection or definitive chemoradiation, according to a statement from Regeneron Pharmaceuticals, and patients may be treated with this combination irrespective of PD-L1 expression or histology.

The approval is based on data from the global phase 3 trial, EMPOWER-Lung 3, which investigated cemiplimab in combination with a physician's choice of platinum-doublet chemotherapy (cemiplimab combination), compared with platinum-doublet chemotherapy alone.

The trial enrolled 466 patients with locally advanced or metastatic NSCLC, irrespective of PD-L1 expression or tumor histology, and with no ALK, EGFR or ROS1 aberrations.

Among those enrolled, 43% had tumors with squamous histology, 67% had tumors with < 50% PD-L1 expression, 15% had inoperable locally advanced disease not eligible for definitive chemoradiation, and 7% had pretreated and clinically stable brain metastases.

Patients were randomized 2:1 to receive either cemiplimab 350 mg (n = 312) or placebo (n = 154) intravenously every 3 weeks, plus histology-specific platinum-doublet chemotherapy.

Efficacy results comparing the combination therapy to chemotherapy alone showed a:

• 22-month median OS versus 13 months, representing a 29% relative reduction in the risk of death (HR, 0.71; 95% CI, 0.53-0.93; P = .014). The 12-month probability of survival was 66% for the cemiplimab combination versus 56% for chemotherapy, per Kaplan-Meier estimates.
• 8-month median PFS versus 5 months, representing a 44% reduction in the risk of disease progression (HR, 0.56; 95% CI, 0.44-0.70; P < .0001). The 12-month probability of PFS for the cemiplimab combination was 38% versus 16% for chemotherapy.
• 43% overall response rate versus 23%.

Cemiplimab previously demonstrated favorable efficacy as monotherapy compared with chemotherapy in the EMPOWER-Lung 1 trial, leading to its 2021 approval for advanced NSCLC with high PD-L1 expression (tumor proportion score ≥ 50%), and with no EGFR, anaplastic ALK or ROS1 aberrations.

Safety was assessed in 312 patients in the cemiplimab combination group (median duration of exposure, 38 weeks) and 153 patients in the chemotherapy group (median duration of exposure, 21 weeks).

The most common adverse reactions occurring in > 15% of patientswere alopecia (37% intervention, 43% placebo), musculoskeletal pain (30% intervention ination, 36% placebo), nausea (25% intervention, 16% placebo), fatigue (23% intervention, 18% placebo), peripheral neuropathy (23% intervention, 19% placebo), and decreased appetite (17% intervention, 12% placebo).

Serious adverse reactions occurred in 25% of patients, with treatment discontinuations due to adverse reactions in 5%, and fatal adverse reactions in 6%.

The trial did not show any new safety signals.