Patients with recurrent or metastatic cervical cancer treated with cemiplimab experienced an improved overall survival, progression-free survival, and overall response rate, leading to priority review from the FDA.
Cemiplimab-rwlc (Libtayo) was granted priority review by the FDA for patients with recurrent or metastatic cervical cancer who have experienced disease progression on or after chemotherapy, according to a press release from Regeneron Pharmaceuticals.1
The clinical decision was based on results of the phase 3 EMPOWER-Cervical 1 trial (NCT03257267). Findings from the overall population highlighted a 31% reduction in the risk of death (HR, 0.69; 95% CI, 0.56-0.84; one-sided P =.00011), as well as a 25% reduction in disease progression (HR, 0.75; 95% CI, 0.63-0.89; one-sided P =.00048) and an overall response rate (ORR) of 16% (n = 50; 95% CI, 13%-21%; one-sided P = .00004). Comparatively, the chemotherapy cohort had an ORR of 6% (n = 19). Patients in the cemiplimab group had a median duration of response of 16 months (95% CI, 12–not yet evaluable) compared with 7 months (95% CI, 5-8) in the chemotherapy group.
A total of 78% of patients had squamous cell carcinoma, 239 of whom were in the cemiplimab group and 238 in the chemotherapy group. These patients notably experienced a 27% reduction in risk of death (HR, 0.73; 95% CI, 0.58-0.91; one-sided P =.00306) and a 29% reduction in disease progression (HR, 0.71; 95% CI, 0.58-0.86; one-sided P =.00026). Additionally, the experimental group achieved an ORR of 18% (n =42; 95% CI, 13%-23%) compared with 7% (n = 16) in the chemotherapy group (95% CI, 4%-11%).
The FDA set a target action date of January 31, 2022.
“In this phase 3 trial, Libtayo demonstrated a significant improvement in overall survival in women with advanced cervical cancer after progression on chemotherapy…” trial investigator Krishnansu S. Tewari, MD, professor and director of the division of gynecologic oncology at the University of California, Irvine, said in a press release.2
Patients who were treated with the cemiplimab monotherapy or investigator’s choice chemotherapy and were enrolled regardless of tumor PD-L1 expression or histology. The end points of the trial was overall survival (OS), which was assessed in patients with squamous cell carcinoma histology, as well as in the total population.
A total of 304 patients were enrolled in the cemiplimab and 304 patients enrolled in the chemotherapy group.
Additional findings from the study indicated that patients in the cemiplimab arm were generally able to improve or maintain their baseline Global Health Status/Quality of Life over time compared with those who were treated with chemotherapy, who experienced clinically meaningful deterioration starting at cycle 8 (P =.00040).
A post-hoc analysis showed that, although assessment of adenocarcinoma was not a prespecified end point, 65 patients treated with cemiplimab and 66 treated with chemotherapy had a 44% reduction in the risk of death (HR, 0.56; 95% CI, 0.36-0.85; nominal one-sided P <.005), as well as a 9% reduction in disease progression (HR, 0.91; 95% CI, 0.62-1.34). Additionally, investigators reported an ORR of 12% (n = 8; 95% CI, 6%-23%) compared with 5% (n = 3; 95% CI, 1%-13%) in the chemotherapy group.
Patients did not experience any new safety signals. Patients who received at least 1 dose of treatment were assessed, including 300 patients in the cemiplimab group and 290 in the chemotherapy group. In 88% of patients in the cemiplimab group and 91% in the chemotherapy group experienced adverse effects (AEs). Some of the most common grade 3 or higher AEs in the cemiplimab and chemotherapy groups, respectively, were asthenia (2% vs 1%) and pyrexia (less than 1% vs, 0%). Patients also experienced immune-related AEs, including 16% of those receiving cemiplimab and less than 1% of those in the chemotherapy group. Additionally, 6% of immune-related AEs were grade 3 or higher in the cemiplimab group, as well as less than 1% in the chemotherapy group. Eight percent of patients in the cemiplimab group and 5% in the chemotherapy group experienced AEs that led to discontinuation.
“Improvements in progression-free survival and objective response rate were also demonstrated in the overall population compared to chemotherapy. Taken together, this landmark trial – which enrolled patients regardless of PD-L1 expression status - helps support the use of Libtayo as a potential new second-line treatment for women with advanced cervical cancer who face a poor prognosis and limited treatment options,” Tewari concluded.