Study of REGN2810 in Patients With Advanced Cutaneous Squamous Cell Carcinoma

ORR was defined as percentage of participants with best overall response (BOR) of complete response (CR) or partial response (PR). For participants with metastatic disease, Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1 was used to determine BOR. For participants with unresectable locally advanced disease, clinical response criteria were used. RECIST v1.1 Criteria: -CR: Disappearance of all target lesions. Any pathological lymph nodes (whether target or non-target) must have reduction in short axis to <10 millimeter (mm) <1 (centimeter (cm). -PR: At least a 30% decrease in the sum of the diameters of target lesions, taking as reference the baseline sum diameters. Clinical Response Criteria: -CR: All target and nontarget lesion(s) no longer visible, maintained for at least 4 weeks and no new lesions. -PR: Decrease of at least 50% in the sum the products of perpendicular longest dimensions of target lesion(s), maintained for at least 4 weeks and no new lesions.

ORR was defined as percentage of participants with BOR of CR or PR. For participants with metastatic disease, RECIST v1.1 was used to determine BOR. For participants with unresectable locally advanced disease, clinical response criteria were used. RECIST v1.1 Criteria: -CR: Disappearance of all target lesions. Any pathological lymph nodes (whether target or non-target) must have reduction in short axis to <10 mm <1 cm. -PR: At least a 30% decrease in the sum of the diameters of target lesions, taking as reference the baseline sum diameters. Clinical Response Criteria: -CR: All target and nontarget lesion(s) no longer visible, maintained for at least 4 weeks and no new lesions. -PR: Decrease of at least 50% in the sum the products of perpendicular longest dimensions of target lesion(s), maintained for at least 4 weeks and no new lesions.

DOR was measured from the time measurement criteria were first met for CR/PR, whichever was recorded first, until the first date of recurrent or Progressive Disease (PD) or death due to any cause in participants with BOR of CR or PR. For participants with metastatic disease, RECIST v1.1 was used to determine BOR. For participants with unresectable locally advanced disease, clinical response criteria were used. RECIST v1.1 Criteria: -PD: At least a 20% increase in the sum of the diameters of target lesions with the sum demonstrating an absolute increase of at least 5 mm (0.5 cm), or the appearance of one or more new lesions and/or unequivocal progression of existing non-target lesions. Clinical Response Criteria: -PD: increase of ≥ 25% (WHO criteria) in the sum of the products of perpendicular longest dimensions of target lesion(s) and/or the appearance of new lesions.

DOR was measured from the time measurement criteria were first met for CR/PR, as defined in Outcome Measure 1, whichever was recorded first, until the first date of recurrent or Progressive Disease (PD) or death due to any cause in participants with BOR of CR or PR. For participants with metastatic disease, RECIST v1.1 was used to determine BOR. For participants with unresectable locally advanced disease, clinical response criteria were used. RECIST v1.1 Criteria: -PD: At least a 20% increase in the sum of the diameters of target lesions with the sum demonstrating an absolute increase of at least 5 mm (0.5 cm), or the appearance of one or more new lesions and/or unequivocal progression of existing non-target lesions. Clinical Response Criteria: -PD: increase of ≥ 25% (World Health Organization (WHO) criteria) in the sum of the products of perpendicular longest dimensions of target lesion(s) and/or the appearance of new lesions.

PFS was measured from start of treatment until the first date of recurrent or PD, or death due to any cause. For participants with metastatic disease, RECIST v1.1 was used to determine PD. For participants with unresectable locally advanced disease, clinical response criteria were used. RECIST v1.1 Criteria: -PD: At least a 20% increase in the sum of the diameters of target lesions with the sum demonstrating an absolute increase of at least 5 mm (0.5 cm), or the appearance of one or more new lesions and/or unequivocal progression of existing non-target lesions. Clinical Response Criteria: -PD: increase of ≥ 25% (WHO criteria) in the sum of the products of perpendicular longest dimensions of target lesion(s) and/or the appearance of new lesions.

PFS was measured from start of treatment until the first date of recurrent or PD, or death due to any cause. For participants with metastatic disease, RECIST v1.1 was used to determine PD. For participants with unresectable locally advanced disease, clinical response criteria were used. RECIST v1.1 Criteria: -PD: At least a 20% increase in the sum of the diameters of target lesions with the sum demonstrating an absolute increase of at least 5 mm (0.5 cm), or the appearance of one or more new lesions and/or unequivocal progression of existing non-target lesions. Clinical Response Criteria: -PD: increase of ≥ 25% (WHO criteria) in the sum of the products of perpendicular longest dimensions of target lesion(s) and/or the appearance of new lesions.

OS was measured from start of treatment until death due to any cause.

CR rate was defined as percentage of participants with BOR of CR. For participants with metastatic disease, RECIST v1.1 was used to determine BOR. For participants with unresectable locally advanced disease, clinical response criteria were used. RECIST v1.1 Criteria: -CR: Disappearance of all target lesions. Any pathological lymph nodes (whether target or non-target) must have reduction in short axis to <10 mm <1 cm. Clinical Response Criteria: -CR: All target and nontarget lesion(s) no longer visible, maintained for at least 4 weeks and no new lesions.

EORTC QLQ-C30 is a 30-question tool used to assess the overall quality of life (QoL) in cancer participants. Items contributing to the GHS/QoL, were scored 1 ("very poor") to 7 ("excellent"). A linear transformation was applied to the raw scores so that transformed score lies between 0 to 100. A higher score indicates better global health status/functioning and a negative change from baseline indicated less improvement.

An AE was defined as any untoward medical occurrence in a participant who received study drug without regard to possibility of causal relationship. Serious Adverse Events (SAEs) were defined as death, a life-threatening AE, inpatient hospitalization or prolongation of existing hospitalization, persistent or significant disability or incapacity, a congenital anomaly or birth defect, or an important medical event that jeopardized participant and required medical intervention to prevent 1 of the outcomes listed in this definition. Treatment-emergent adverse events (TEAEs) are defined as those not present at baseline or represent the exacerbation of a condition present at baseline during the on-treatment period or follow-up period. A summary of other non-serious AEs and all serious AEs, regardless of causality is located in Reported AE section.

ORR was defined as percentage of participants with BOR of CR or PR. Expression level of PD-L1 was assessed in tumor biopsy samples by immunohistochemistry (IHC). -CR: All target and nontarget lesion(s) no longer visible, maintained for at least 4 weeks and no new lesions. -PR: Decrease of at least 50% in the sum the products of perpendicular longest dimensions of target lesion(s), maintained for at least 4 weeks and no new lesions.

DOR was measured from the time measurement criteria are first met for CR/PR, as defined in Outcome Measure 13, whichever was recorded first, until the first date of recurrent or PD or death due to any cause in participants with BOR of CR or PR. Expression level of PD-L1 was assessed in tumor biopsy samples by IHC. -PD: increase of ≥ 25% (WHO criteria) in the sum of the products of perpendicular longest dimensions of target lesion(s) and/or the appearance of new lesions.

PFS was measured from time of enrollment until the first date of recurrent or progressive disease, or death due to any cause. Expression level of PD-L1 was assessed in tumor biopsy samples. -PD: increase of ≥ 25% (WHO criteria) in the sum of the products of perpendicular longest dimensions of target lesion(s) and/or the appearance of new lesions.