Danny Rischin, MD, MBBS, FRACP
If approved by the FDA, the PD-1 inhibitor cemiplimab may become a standard of care for select patients with metastatic and locally advanced cutaneous squamous cell carcinoma (CSCC), said Danny Rischin, MD, MBBS, FRACP, as there are currently no available agents in the landscape.
In April 2018, cemiplimab was granted a priority review by the FDA for the treatment of patients with metastatic CSCC and locally advanced CSCC who are not eligible for surgery. The priority review was based on phase I/II findings from the EMPOWER-CSCC 1 study (NCT02760498), which showed an overall response rate (ORR) of 46.3% in patients with advanced CSCC.1
In data from a phase II study presented at the 2018 ASCO Annual Meeting and published in the New England Journal of Medicine
, cemiplimab induced an ORR of 47.5% in patients with metastatic CSCC.2,3
Also in the phase II study presented at ASCO, 28 of 59 patients had a response at a median follow-up of 7.9 months, including 4 (6.8%) partial responses and 24 (40.7%) complete responses. Of the 28 responders, 57% had responses over 6 months, and 82% had an ongoing response and continued to receive cemiplimab. The FDA is scheduled to make its decision on the cemiplimab application by October 28, 2018.
“These patients often have advanced disease with limited treatment options, and are often elderly with comorbidities,” said Rischin. “Some patients on the trial were only estimated to live for a few months, and are back to living normal lives at nearly 2 years now. It’s quite remarkable compared with the options previously.”
In an interview with OncLive®
, Rischin, director, Division of Cancer Medicine, head, Department of Medical Oncology, Peter MacCallum Cancer Centre, Melbourne, Australia, discussed the potential for cemiplimab as a novel PD-1 inhibitor for patients with metastatic and locally advanced CSCC.
OncLive: Can you share the background of this study?
: There are no approved agents for metastatic CSCC. CSCC is a common disease, but there is a group of patients who progress after standard treatment of surgery, and up to now, there have not been any treatments for these patients. There are a couple of features of CSCC that led us to believe that it might be particularly responsive to immunotherapy. This tumor has one of the highest tumor mutational burdens and it is associated with immunosuppression. These 2 features have led us to believe immune checkpoint inhibitors were worth exploring. That was the background hypothesis that led to the phase II study.
What is the design of the study?
This was a single-arm, phase II study for patients with metastatic CSCC with distant metastases or with metastases to lymph nodes that were no longer amenable to any curative surgery or radiotherapy. The eligibility was restricted to immune-competent patients, so those on immunosuppressive therapy, with chronic lymphocytic leukemia, or transplant recipients were eligible. We enrolled 59 patients on this trial. Typical for a CSCC population, they were elderly with a median age of 71—in fact, the oldest patient on the trial was 93. Most of these patients had been heavily pretreated; 85% had previously received radiotherapy and 56% had previous systemic therapy of some kind.
What was the activity reported with cemiplimab?
The primary objective was to determine the response rate, which was evaluated using RECIST v1.1 criteria and independent central review. The ORR was 47.5%, so just under half of patients had a response. We also found that more than 60% of patients had what we call durable disease control—so either a response or lack of progression for over 105 days. A large proportion of patients derived significant benefit.