Cemiplimab ( Libtayo ) monotherapy achieves clinically meaningful activity in patients with advanced cutaneous squamous cell carcinoma ( CSCC ) ( metastatic [ mCSCC ] or locally advanced [ laCSCC ] not amenable to curative surgery or curative radiation ) and has a safety profile consistent with other anti-PD-1 agents.
Based on initial data ( median follow-up of 9.4 months in the pivotal study ), Cemiplimab was approved for the treatment of patients with advanced CSCC.
Historical data shows median overall survival ( OS ) of approximately 15 months with conventional chemotherapy or EGFR inhibitors ( ASCO 2019, e21033 ).
Researchers have presented approximately 1-year additional follow-up from the largest prospective data set in advanced CSCC.
Patients received Cemiplimab 3 mg/kg Q2W ( Group [Gp] 1; mCSCC; Gp 2, laCSCC ) or Cemiplimab 350 mg Q3W ( Gp 3, mCSCC ).
The primary endpoint was objective response rate ( ORR; complete response + partial response ) per independent central review ( ICR ).
Data are presented per investigator review ( INV ).
193 patients were enrolled ( Gp 1, n = 59; Gp 2, n = 78; Gp 3, n = 56 ). 128 patients had received no prior anti-cancer systemic therapy, 65 patients were previously treated.
As of Oct 11, 2019 ( data cut-off ), median duration of follow-up was 15.7 months ( range: 0.6–36.1 ) among all patients; 18.5 months ( range: 1.1–36.1 ) for Gp 1, 15.5 months ( range: 0.8–35.0 ) for Gp 2, and 17.3 months ( range: 0.6–26.3 ) for Gp 3.
ORR per investigator review was 54.4% ( 95% CI: 47.1–61.6 ) for all patients; 50.8% ( 95% CI: 37.5–64.1 ) for Gp 1, 56.4% ( 95% CI: 44.7–67.6 ) for Gp 2, and 55.4% ( 95% CI: 41.5–68.7 ) for Gp 3.
ORR per investigator review was 57.8% ( 95% CI: 48.8–66.5 ) among treatment-naïve patients and 47.7% ( 95% CI: 35.1–60.5 ) among previously treated patients.
Median duration of response ( DOR ) has not been reached ( observed DOR range: 1.8–34.2 months ).
In responding patients, estimated proportion of patients with ongoing response at 24 months was 76.0% ( 95% CI: 64.1–84.4 ).
Median overall survival has not been reached. Estimated OS at 24 months was 73.3% ( 95% CI: 66.1–79.2 ).
The most common treatment-emergent adverse events ( TEAEs ) by any grade were fatigue ( 34.7% ), diarrhea ( 27.5% ), and nausea ( 23.8% ).
The most common grade 3 TEAEs or more were hypertension ( 4.7% ) and anemia and cellulitis ( each 4.1% ).
In conclusion, for patients with advanced cutaneous squamous cell carcinoma, Cemiplimab achieves ORRs, DOR and survival superior to what has been reported with other agents. ( Xagena )
Source: American Society of Clinical Oncology ( ASCO ) Virtual Meeting, 2020