SUMMARY: The FDA on November 8, 2022, approved LIBTAYO® (Cemiplimab-rwlc) in combination with platinum-based chemotherapy for adult patients with advanced Non-Small Cell Lung Cancer (NSCLC) with no EGFR, ALK, or ROS1 aberrations. The American Cancer Society estimates that for 2022, about 236,740 new cases of lung cancer will be diagnosed and 135,360 patients will die of the disease. Lung cancer is the leading cause of cancer-related mortality in the United States. Non-Small Cell Lung Cancer (NSCLC) accounts for approximately 85% of all lung cancers and Adenocarcinoma now is the most frequent histologic subtype of lung cancer.
Immune checkpoints are cell surface inhibitory proteins/receptors that are expressed on activated T cells. They harness the immune system and prevent uncontrolled immune reactions by switching off the T cells of the immune system. Immuno-Oncology (IO) therapies unleash the T cells by blocking the Immune checkpoint proteins, thereby resulting in T cell proliferation, activation, and a therapeutic response. Immunotherapy with PD-1 (Programmed cell Death 1) and PD-L1 (Programmed cell Death Ligand 1) inhibitors have demonstrated a clear survival benefit both as a single agent or in combination, compared with standard chemotherapy, in both treatment-naive and previously treated patients for advanced NSCLC. It is now standard therapy for patients with lung cancer.
KEYTRUDA® (Pembrolizumab; anti PD-1) and TECENTRIQ® (Atezolizumab; anti PD-L1) are both approved in combination with platinum-based chemotherapy for the first-line treatment of patients with metastatic NSCLC. The FDA approval of TECENTRIQ® with platinum-doublet chemotherapy is however limited to non-squamous histology.
LIBTAYO® is a fully human monoclonal antibody targeting the immune checkpoint receptor PD-1. LIBTAYO® monotherapy was approved by the FDA in 2021 after it demonstrated significantly improved Overall Survival and Progression Free Survival compared with chemotherapy, in patients with advanced Non-Small Cell Lung Cancer with PD-L1 of at least 50%. The researchers in EMPOWER-Lung 3 evaluated the efficacy of first line LIBTAYO® in combination with investigator’s choice of platinum-doublet chemotherapy, among patients with advanced NSCLC, with either squamous or non-squamous histology, and any level of PD-L1 expression.
EMPOWER-Lung 3 is a randomized, multicenter, multinational, double-blind, active-controlled Phase III trial in which 466 patients with advanced NSCLC who had not received prior systemic treatment were randomized (2:1) to receive either Cemiplimab 350 mg IV once every 3 weeks (N=312) or placebo (N=154) every 3 weeks, in combination with four cycles of chemotherapy. Investigators’ choice of histology-specific chemotherapy options included Paclitaxel plus Carboplatin, Paclitaxel plus Cisplatin, Pemetrexed plus Carboplatin and Pemetrexed plus Cisplatin. Patients were treated for a maximum of 108 weeks, or until disease progression or unacceptable toxicity. For patients with non-squamous histology assigned to a Pemetrexed-containing regimen, maintenance Pemetrexed was mandatory. Patients were enrolled irrespective of PD-L1 expression or tumor histology and had advanced or metastatic NSCLC, with no ALK, EGFR or ROS1 aberrations. Among those enrolled, 43% had tumors with squamous histology, 67% had tumors with less than 50% PD-L1 expression, 15% had inoperable locally advanced disease not eligible for definitive chemoradiation, and 7% had pretreated and clinically stable brain metastases. The Primary endpoint was Overall Survival (OS). Secondary endpoints included Progression Free Survival (PFS) and Overall Response Rate (ORR) as assessed by Blinded Independent Central Review (BICR).
The trial was stopped early upon recommendation by the Independent Data Monitoring Committee (IDMC) after the LIBTAYO® combination demonstrated a statistically significant and clinically meaningful improvement in Overall Survival, compared to placebo plus chemotherapy. The median OS was 21.9 months in the LIBTAYO® plus chemotherapy group and 13.0 months in the placebo plus chemotherapy group (HR=0.71; P=0.0140). This represented a 21% relative reduction in the risk of death in the LIBTAYO® plus chemotherapy group. The 12-month probability of survival was 66% for the LIBTAYO® combination versus 56% for chemotherapy.
The median PFS per BICR was 8.2 months in the LIBTAYO® plus chemotherapy group and 5.0 months in the placebo plus chemotherapy group (HR=0.56; p<0.0001). This represented a 44% reduction in the risk of disease progression in the LIBTAYO® plus chemotherapy group. The 12-month probability of PFS for the LIBTAYO® combination was 38%, versus 16% for chemotherapy. The confirmed ORR per BICR was 43% and 23% in the respective treatment groups and the median Duration of Response was 16 months versus 7 months respectively. The most common (15% or more) adverse reactions were alopecia, musculoskeletal pain, nausea, fatigue, peripheral neuropathy, and decreased appetite.
It was concluded that LIBTAYO® is only the second anti-PD-1/PD-L1 agent to show efficacy in advanced Non-Small Cell Lung Cancer either as monotherapy in those with PD-L1 expression 50% or more, or in combination with chemotherapy, irrespective of PD-L1 expression or tumor histology.
Cemiplimab plus chemotherapy versus chemotherapy alone in non-small cell lung cancer: a randomized, controlled, double-blind phase 3 trial. Gogishvili M, Melkadze T, Makharadze T, et al. Nature Medicine 2022;(28):2374-2380.