Poster Presentation Clinical Oncology Society of Australia Annual Scientific Meeting 2022

Phase 3 study of Pembrolizumab as adjuvant treatment in high-risk locally advanced (LA) Cutaneous Squamous Cell Carcinoma (cSCC) (#454)

Jenny Lee 1 , Marcin Dzienis 2 , Chrysalyne Schmults 3 , Michael Schneker 4 , Åse Bratland 5 , Mikhail Klochikhin 6 , Markus Gifoni 7 , Dmitry Kirtbaya 8 , Julian Rivera-Diaz 9 , Mitchell Chipman 10 , Jessica L. Geiger 11 , Anne L. S. Chang 12 , Gregory A. Daniels 13 , Ezra E. W. Cohen 13 , Lili Yao 14 , Burak Gumuscu 14 , Jianda Yuan 14 , Alexander Guminski 15 , Elani Bowers 16
  1. Chris O’Brien Lifehouse, Camperdown, NSW, Australia
  2. Gold Coast University Hospital, Southport, QLD, Australia
  3. Dana-Farber Cancer Institute, Boston, MA, USA
  4. University of Medicine & Pharmacy of Craiova, Craiova, Romania
  5. Olso University Hospital, Olso, Norway
  6. Yaroslavl Regional SBIH Clinical Oncology Hospital, Yaroslavl, Russia
  7. Oncocentro Ceara, Fortalez, Brazil
  8. Oncological Dispensary #2 of Ministry of Health of Krasnodar region, Sochi, Russia
  9. Oncologos del Occidente S.A.S, Pereira, Colombia
  10. Alfred Health, Melbourne, VIC, Australia
  11. Cleveland Clinic, Cleveland, OH, USA
  12. Stanford University Medical Center, Stanford, CA, USA
  13. UC San Diego, La Jolla, CA, USA
  14. Merck & Co., Inc., Rahway, NJ, USA
  15. Royal North Shore Hospital, St Leonards, NSW, Australia
  16. MSD, Melbourne, VIC, Australia

Aims: Treatment options are needed for patients with high-risk, LA cSCC who experience recurrence after surgery. Durable antitumor activity has been observed with cemiplimab and pembrolizumab in advanced metastatic cSCC. The double-blind, phase 3 KEYNOTE-630 study (NCT03833167) is designed to evaluate adjuvant pembrolizumab in resectable, high-risk, LA cSCC.

Methods: Eligibility criteria include LA cSCC with ≥1 high-risk feature: histologically involved nodal disease with extracapsular extension, with ≥1 lymph node >2 cm in diameter or ≥2 lymph nodes involved; any index tumor with ≥2 of the following: tumor ≥4 cm with >6-mm depth or invasion beyond subcutaneous fat, multifocal perineural invasion for nerves <0.1 mm in diameter (≥3 foci) or any involved nerve ≥0.1 mm in diameter, poor differentiation and/or sarcomatoid and/or spindle cell histology, recurrent disease, satellite lesions and/or in-transit metastases, lymphatic or vascular involvement; any gross cortical bone, skull base, and/or skull base foramen invasion. Patients must have undergone complete macroscopic resection, have ECOG PS 0/1, received adequate postoperative dose of hypofractionated or conventional RT, including BED EQD2 >48 Gy, and completed adjuvant RT ≥4 and ≤16 weeks from randomization. Approximately 570 patients will be randomly assigned 1:1 to pembrolizumab 400 mg IV Q6W or placebo for ≤9 cycles (1 year) and stratified by extracapsular extension, cortical bone invasion, and prior systemic therapy (all, yes vs no). Patients receiving placebo may be eligible to cross over to receive pembrolizumab (≤18 cycles) if first biopsy-proven recurrence occurs ≤5 years. In the pembrolizumab arm, eligible patients may receive pembrolizumab retreatment (≤18 cycles). Primary end point: RFS. Secondary end points include OS, HRQoL, and safety.

Results: Enrollment is ongoing at sites in Asia, Australia, Europe, and North and South America.

Conclusions: Results will provide clarity on efficacy and safety of adjuvant pembrolizumab in patients with high-risk, LA cSCC.

Clinical Trial registration: NCT03833167