Dr Gross on Updated Survival Outcomes With Neoadjuvant Cemiplimab in CSCC

Neil D. Gross, MD, FACS, surgeon-scientist, director, Clinical Research, the Department of Head and Neck Surgery, the University of Texas MD Anderson Cancer Center, discusses 1-year follow-up data from a phase 2 study (NCT04154943) of neoadjuvant cemiplimab (Libtayo) in cutaneous squamous cell carcinoma (CSCC).

In part 1 of this non-randomized, multicenter study, patients with stage II-IV CSCC received neoadjuvant cemiplimab followed by surgery with curative intent. Subsequent treatment in part 2 was determined by investigator discretion, and included up to 48 weeks of adjuvant cemiplimab, radiotherapy, or observation only.

Results demonstrated a robust 1-year event-free survival (EFS) rate with the cemiplimab regimen, Gross says. After a median follow-up of 18.7 months, the estimated 12-month EFS was 89.0% (95% CI, 79.1%-94.3%) for patients in the overall population (n = 79), he reports. This included a major pathologic response rate of 88.9% (95% CI, 43.3%-98.4%) and a pathologic partial response rate of 100.0% (95% CI, not evaluable [NE]- NE). Notably, the 40 patients who achieved a pathologic complete response (pCR) had more favorable outcomes, achieving a 12-month EFS of 94.9% (95% CI, 81.0%-98.7%) and experiencing no disease recurrence, Gross adds. Conversely, those who did not undergo surgery or were non-responders demonstrated an estimated 12-month EFS of 72.0% (95% CI, 43.8%-87.7%).

Lastly, the estimated 12-month overall survival (OS) rate for the overall patient cohort was 92%, further emphasizing the clinical benefit of this treatment approach. There were no new safety concerns associated with neoadjuvant cemiplimab, indicating that its use in this setting is well-tolerated.

The absence of disease recurrence among patients who achieved a pCR underscores the potential for cemiplimab to enhance long-term disease control and highlights its role in improving patient outcomes. Overall, these findings support the continued investigation of neoadjuvant cemiplimab in a planned phase 3 trial, Gross concludes.