Cemiplimab has potent activity in locally advanced advanced skin squamous cell carcinoma

Among patients with locally advanced skin squamous cell carcinoma (CSCC) enrolled in the EMPOWER-CSCC-1 Phase II pivotal study, cemiplimab (Libtayo) exhibited significant antitumor activity and similar durable responses to those observed in patients with metastatic CCSC. enrolled in the same study.

In 78 patients with locally advanced SCCS, the objective response rate (ORR) badessed by an independent central review according to RECIST 1.1 was 43.6%.¹ said Michael R. Migden, MD, at the ASCO Annual Meeting in 2019. The median duration of response, median progression-free survival and median overall survival had not yet been reached at the time of the cut data.

The probability of no progression at 12 months estimated by Kaplan-Meier was 58.1% (95% CI, 43.7% to 70%), and the estimated probability of survival at 12 months was 93%. , 2% (95% CI, 84.4% to 97.1%). .

The 43.6% TRG in this group is similar to that observed in patients with metastatic CCSC, with a response rate of 47%. The results of this last cohort were published last year in the New England Journal of Medicine.²

The results of the study led to the approval of cemiplimab by the FDA for patients with metastatic CCSC or those with locally advanced disease who are not candidates for curative surgery or radiotherapy. The recommended dosage is 350 mg intravenously every 3 weeks until progression of the disease or unacceptable toxicity.³

"Prior to the approval of cemiplimab by the FDA, there was no approved treatment for advanced, locally advanced or metastatic CSCC," said Migden, Associate Professor, Department of Dermatology and MD Anderson Cancer Center of the University of Texas at Houston. "The treatments used were standard chemotherapy agents or agents targeting epidermal growth factors badociated with a weaker response, but most importantly, a shorter response time and many tolerance problems.

Patients with a locally advanced disease could be included in the cohort if they were not candidates for surgery or radiation therapy, according to the investigator of the trial. Surgery was considered inappropriate in patients who had recurrence of the disease in the same location after two or more surgeries, and curative resection was considered unlikely for those for whom the clinician anticipated that the surgery would lead to complications or deformity. important, or in the event of significant local injuries. invasion that prevented complete resection.

Radiation therapy was considered inappropriate in patients whose subsequent treatment would result in an excessive cumulative radiation dose, in those with tumors unlikely to respond to radiotherapy or if the benefit / risk ratio of radiotherapy was considered unfavorable.

Eligible patients had to have an ECOG performance index of 0 or 1, an adequate organ function and the presence of at least one measurable lesion.

The primary site of CSCC was the head / neck in 79.5% of patients, one end in 17.9% and the trunk in 2.6%. Twelve patients (15.4%) had already received systemic therapy related to cancer and 43 (55.1%) had already undergone radiotherapy.

At the data threshold (October 10, 2018), 6.4% of patients completed the planned treatment, 30.8% continued treatment, and 62.8% discontinued treatment due to disease progression (21%). 8%), adverse effects (AE), the decision of the investigator, a complete treatment. response (CR) to treatment, or patient decision.

After a median follow-up of 9.3 months, 10 patients (12.8%) had a CR, 24 (30.8%) had a partial response (PR) and 28 (35.9%) had a stable disease (DS) as the best answer. The long-term disease control rate was 62.8% and the median time to response was 1.9 months.

These results were similar to those reported in the metastatic CSCC group, with 7% of patients achieving CR, 41% with RA, and 15 with SD as the best response. The rate of sustained control of the disease was 61% and the median time to response was 1.9 months.

In patients with locally advanced disease, 12 patients presented responses of up to 12 months and the longest response time to the data cut-off was 24.2 months or more.

The ORR was also evaluated in a subgroup badysis where patients were stratified according to the reasons why they were not considered candidates for curative surgery, and these data may support a use Cemiplimab's earlier onset in this patient population, explained poster presenter Katharine A. Price MD, of the Mayo Clinic's Head and Neck Cancer Center in Rochester, Minnesota. Standard treatment approaches in locally advanced CCHS often exhaust local therapies in the first place, she noted.

Among the 20 patients with unresectable lesions of CSCC with significant local invasion, the ORR was 50%. Among the 30 patients with lesions located in anatomically difficult areas for which surgery could result in severe deformity or dysfunction, the rate of MMR was 56.7%. Of the 25 patients with CSCC lesions at the same location after 2 or more surgeries and where curative resection is considered unlikely, the ORM was only 24%.