LIBTAYO achieved rapid, substantial, and durable responses1,2,*

Median time to tumor response was 1.9 months.
Time to response1,2

Median time to response was rapid (1.9 months), based on 2 open-label, single-arm trials that did not include comparisons to other treatments (first assessment was performed at 8 weeks; range: 1.7-7.6 months)

47.2% of patients received an objective response.
Objective response rate1,2

47.2% ORR (51 of 108 patients;
95% Cl, 37.5%, 57.1%)

43.5% PR (47 of 108 patients);
3.7% CR (4 of 108 patients)

61% of responders reached a DoR of greater than or equal to 6 months.
Duration of response

61% of responders (31 of 51) reached
a DoR of ≥6 months1,2

Median DoR was not reached
(range: 1-15.2+ months)1-3

80% of responses (41 of 51) were ongoing at last response assessment2

  • * Results as of data cutoff. Group 2 patients (laCSCC; cemiplimab-rwlc 3 mg/kg Q2W) who started treatment less than 9 months prior to the data cutoff date and all Group 3 patients (mCSCC; cemiplimab-rwlc 350 mg Q3W) from Study 1540 are excluded from the efficacy analysis set.2
  • Partial response is defined as a decrease of 30% or greater in the sum of the diameters of target lesions, taking as reference the baseline sum of diameters, per RECIST 1.1. Partial response of externally visible disease is defined as a decrease of 50% or greater in the sum of products of perpendicular longest dimensions of target lesions, per WHO Criteria. Responses had to be maintained for at least 4 weeks.2
  • Only includes patients with complete healing of prior cutaneous involvement; locally advanced CSCC patients in Study 1540 required biopsy to confirm CR.1
  • "+" denotes ongoing at last assessment.1
  • CI, confidence interval; CR, complete response; CSCC, cutaneous squamous cell carcinoma; DoR, duration of response; laCSCC, locally advanced cutaneous squamous cell carcinoma; mCSCC, metastatic cutaneous squamous cell carcinoma; ORR, objective response rate; PR, partial response; Q2W, every 2 weeks; Q3W, every 3 weeks; RECIST, Response Evaluation Criteria in Solid Tumors; WHO, World Health Organization.


Best percent change in target lesions as determined by independent central review2,*

Chart showing the best percent change in target lesions from baseline during the clinical trials.

Each bar in the figure represents best percent change from baseline in the sum of target lesions based on RECIST 1.1 (bars without a dot) or the sum of products of externally visible target lesions based on WHO Criteria (bars with a dot) during the study period in the 87 patients with at least 1 evaluable tumor assessment. Lesion measurements after progression are excluded. Increases in the sum of target lesions greater than 100% are reported as 100%.

  • * Results as of data cutoff. Group 2 patients (laCSCC; cemiplimab-rwlc 3 mg/kg Q2W) who started treatment less than 9 months prior to the data cutoff date and all Group 3 patients (mCSCC; cemiplimab-rwlc 350 mg Q3W) from Study 1540 are excluded from the efficacy analysis set.2
  • a Complete response is defined as disappearance of all target lesions for at least 4 weeks. Any pathological lymph nodes (whether target or nontarget) must have reduction in short axis to <10 mm (<1 cm). Only includes patients with complete healing of prior cutaneous involvement; locally advanced CSCC patients in Study 1540 required biopsy to confirm complete response.1,2
  • b Partial response is defined as a decrease of 30% or greater in the sum of the diameters of target lesions, taking as reference the baseline sum of diameters, per RECIST 1.1. Partial response of externally visible disease is defined as a decrease of 50% or greater in the sum of products of perpendicular longest dimensions of target lesions, per WHO Criteria. Responses had to be maintained for at least 4 weeks.2
  • c Progressive disease is defined as an increase of 20% or greater in the sum of the diameters of target lesions, per RECIST 1.1, taking as reference the smallest sum on study (this includes the baseline sum if that is the smallest on study). In addition to the relative increase of 20%, the sum must also demonstrate an absolute increase of at least 5 mm (0.5 cm). Progression of externally visible disease is defined as an increase of 25% or greater in the sum of products of perpendicular longest dimensions of target lesions, per WHO Criteria. (Note: the appearance of 1 or more new lesions is also considered progression.)2
  • d Other nonresponders are defined as all other lesions that do not meet the criteria for complete response, partial response, or progressive disease, including those without sufficient shrinkage to qualify for partial response or sufficient increase to qualify for progressive disease, taking as reference the smallest sum of diameters on study.2
  • CSCC, cutaneous squamous cell carcinoma; laCSCC, locally advanced cutaneous squamous cell carcinoma; mCSCC, metastatic cutaneous squamous cell carcinoma; Q2W, every 2 weeks; Q3W, every 3 weeks; RECIST, Response Evaluation Criteria in Solid Tumors; WHO, World Health Organization.
  1. LIBTAYO (cemiplimab-rwlc) injection full U.S. prescribing information. Regeneron Pharmaceuticals, Inc., and sanofi-aventis U.S. LLC.
  2. Data on file. Regeneron Pharmaceuticals Inc.
  3. Migden MR et al. N Engl J Med. 2018;379(4):341-351.