麻豆传媒

MADRID -- Treatment with cemiplimab (Libtayo) followed by surgery showed encouraging survival rates in patients with resectable stage II-IV cutaneous squamous cell carcinoma (SCC), according to follow-up results from a small single-arm phase II study.

Of nearly 80 patients in the study, 14% had an event-free survival (EFS) event over a median follow-up of 18.7 months, reported Neil D. Gross, MD, of the University of Texas MD Anderson Cancer Center in Houston, at the European Society for Medical Oncology (ESMO) annual congress.

Estimated 12-month EFS rates reached 89% overall, and 94.9% in patients who had a pathologic complete response, according to the study, which was published simultaneously in .

"In fact, the EFS of patients who had any pathological response was superior to that of patients who had no surgery or were non-responders," Gross said.

Considering that the cumulative effects of standard treatment (typically surgery and radiation) for advanced, resectable cutaneous SCC can lead to a decrease in patient function and quality of life, Gross and colleagues suggested that neoadjuvant cemiplimab could help to address an unmet need in this patient population.

"These data support the development of a randomized phase III trial, which is underway and set to begin enrollment in 2024," Gross said.

Results from this study presented last year at ESMO showed that 40 of the 79 patients in the study experienced a pathologic complete response with neoadjuvant cemiplimab (51%, 95% CI 39-62), while another 10 had a pathological major response (13.3%, 95% CI 6-22).

ESMO discussant Caroline Robert, MD, PhD, of Gustave Roussy in Villejuif, France, noted that these "impressive" results were achieved despite the fact that most patients did not receive adjuvant radiotherapy or adjuvant cemiplimab. "Do we need adjuvant radiotherapy? Do we need adjuvant treatment?" she asked. "It really needs to be totally reconsidered."

The enrolled 79 patients with resectable stage II-IV cutaneous SCC in Australia, Germany, and the U.S. from March 2020 to July 2021. Median age was 73 years, 85% were men, and 87% were white. Most patients (76%) had an Eastern Cooperative Oncology Group performance status of 0; 48% had stage III disease and 46% had stage IV disease. Sixty percent presented with nodal metastases.

Patients received up to four planned doses of neoadjuvant cemiplimab 350 mg intravenously every 3 weeks, and 70 underwent surgery. The rest withdrew consent or were lost to follow-up.

After surgery, it was left to the investigators' discretion whether the patients received adjuvant cemiplimab for up to 48 weeks, adjuvant radiotherapy, or observation, based on local pathology review.

Of the patients, 17 received adjuvant radiotherapy, 16 received adjuvant cemiplimab, and 32 were only observed.

"In patients who had a pathological complete response by independent pathological review, only one received adjuvant radiation treatment," Gross said. "Notably, there were no recurrences among the 40 patients with pathological complete responses, despite the fact that only one received adjuvant radiation."

Six patients who underwent surgery had a disease-free survival (DFS) event, with an estimated 12-month DFS rate of 92%. Nine of the 79 patients died, with an estimated 12-month overall survival rate of 92%.

Four of 16 patients who received adjuvant cemiplimab had grade 3 adverse events, including one who had increased blood potassium, one who had traumatic limb amputation, and two who had serious adverse events (one cardiomyopathy and one hypophysitis). There were no grade 4 adverse events.

One patient died from an exacerbation of congestive heart failure during neoadjuvant treatment. This was the only death in the study that was possibly treatment related, Gross and team noted.

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