Libtayo som monoterapi ökar totalöverlevnaden i första linjens behandling av avancerad NSCLC

• In the overall trial population, Libtayo reduced risk of death by 32% compared to chemotherapy
• In a prespecified analysis of patients with confirmed PD-L1 expression of ≥50%, Libtayo reduced risk of death by 43%

PARIS and TARRYTOWN, N.Y. – September 21, 2020 – Positive pivotal trial data for the investigational use of PD-1 inhibitor Libtayo^® (cemiplimab) in first-line locally advanced or metastatic non-small cell lung cancer (NSCLC) were shared in a presentation at the European Society for Medical Oncology (ESMO) Virtual Congress 2020.

The trial compared cemiplimab monotherapy to platinum-doublet chemotherapy in patients whose tumor cells expressed PD-L1, including those whose cancers had confirmed PD-L1 expression of ≥50%. These results form the basis of regulatory submissions, including in the U.S. and European Union.

In the overall trial population (n=710), the median follow-up was 13 months for both cemiplimab (n=356; range: <1-32 months) and chemotherapy (n=354; range: <1-32 months). Among these patients, cemiplimab demonstrated the following results compared to chemotherapy:

• 32% reduced risk of death (hazard ratio [HR]=0.68; 95% confidence interval [CI]: 0.53-0.87; p=0.0022).
• 22-month median overall survival (OS; 95% CI: 18 months to not yet evaluable) compared to 14 months (95% CI: 12-19 months).
• 41% reduced risk of disease progression (HR=0.59; 95% CI: 0.49-0.72; p<0.0001). The median progression-free survival (PFS) was 6.2 months (95% CI: 4.5-8.3 months) compared to 5.6 months (95% CI: 4.5-6.1 months).
• 37% objective response rate (ORR; 95% CI: 32-42%; 3% complete response [CR] and 33% partial response [PR] rate) compared to 21% ORR (95% CI: 17-25%; 1% CR and 20% PR rate).

A prespecified analysis of data from patients whose cancers had confirmed PD-L1 expression ≥50% (n=563) was also conducted. In this group, the median follow-up was 11 months for both cemiplimab (n=283; range: <1-32 months) and chemotherapy (n=280; range: <1-30 months), and cemiplimab demonstrated the following results compared to chemotherapy:

• 43% reduced risk of death (HR=0.57; 95% CI: 0.42-0.77; p=0.0002).
• Median OS was not yet reached (95% CI: 18 months to not yet evaluable) compared to 14 months (95% CI: 11-18 months).
• 46% reduced risk of disease progression (HR=0.54; 95% CI: 0.43-0.68; p<0.0001). The median PFS was 8 months (95% CI: 6-9 months) compared to 6 months (95% CI: 5-6 months).
• 39% ORR (95% CI: 34-45%; 2% CR and 37% PR rate) compared to 20% ORR (95% CI: 16-26%; 1% CR and 19% PR rate).

The trial also found a direct correlation between tumor response and PD-L1 expression level in cemiplimab-treated patients. The ORR was highest (46%; range: 36-56%) in tumors with ≥90% PD-L1 expression, with target tumors shrinking by more than 40% after 6 months of treatment on average (per last observation carried forward method). This correlation with PD-L1 expression level was not observed with chemotherapy.

In the overall trial population, the median duration of exposure to cemiplimab was 27 weeks (range: <1-115 weeks) and 18 weeks for chemotherapy (range: <1-87 weeks). Overall adverse events (AEs) occurred in 88% of cemiplimab patients and 94% of chemotherapy patients. Grade 3 or higher AEs occurred in 37% of cemiplimab patients and 49% of chemotherapy patients. Immune-mediated AEs were reported in 17% of cemiplimab patients and included hypothyroidism (6%), hyperthyroidism (4%), pneumonitis (2%), hepatitis (2%), skin adverse reaction (2%), arthritis, increased blood thyroid stimulating hormone, thyroiditis, colitis, nephritis and peripheral neuropathy (each 1%). Treatment discontinuation due to an AE occurred in 6% of cemiplimab patients and 4% of chemotherapy patients. No new cemiplimab safety signals were observed.

Cemiplimab is being jointly developed by Regeneron and Sanofi under a global collaboration agreement. The use of cemiplimab to treat advanced NSCLC is investigational and has not been fully evaluated by any regulatory authority.

About the Phase 3 trial

The open-label, randomized, multi-center Phase 3 trial investigated the first-line treatment of cemiplimab monotherapy compared to platinum-doublet chemotherapy in squamous or non-squamous advanced NSCLC that tested positive for PD-L1 in ≥50% of tumor cells but not ALK, EGFR or ROS1. PD-L1 expression was confirmed using the PD-L1 IHC 22C3 pharmDx kit. The trial included 712 patients with either locally advanced NSCLC (Stage IIIB/C), who were not candidates for surgical resection or definitive chemoradiation or had progressed after treatment with definitive chemoradiation, or previously untreated metastatic NSCLC (Stage IV).

Patients were randomized 1:1 to receive either cemiplimab 350 mg administered intravenously every three weeks for up to 108 weeks or an investigator-selected, standard-of-care, platinum-based, doublet chemotherapy regimen for 4 to 6 cycles (with or without histology relevant maintenance pemetrexed chemotherapy). The co-primary endpoints are OS and PFS, and secondary endpoints include overall response rate, duration of response and quality of life.

The trial was designed to reflect current and emerging treatment paradigms. Inclusion criteria allowed patients with NSCLC who had: controlled hepatitis B, hepatitis C or HIV; pre-treated and stable brain metastases; and/or locally advanced disease that had progressed after definitive chemoradiation. Patients whose disease progressed in the trial were able to change their therapy: those in the chemotherapy arm were allowed to crossover into the cemiplimab arm, while those in the cemiplimab arm were allowed to combine cemiplimab treatment with 4 to 6 cycles of chemotherapy.

A prespecified interim analysis was performed after 50% of OS events. Due to a highly significant improvement in OS at the interim analysis, the trial was modified to allow all patients to receive cemiplimab based on an Independent Data Monitoring Committee recommendation.