Pembrolizumab in Treating Patients With Relapsed or Refractory Stage IB-IVB Mycosis Fungoides or Sezary Syndrome

This phase 2 single arm clinical trial assessed the efficacy of pembrolizumab in patients with previously treated mycosis fungoides or Sezary syndrome. Pembrolizumab was found to have a 38% overall response rate, and a 27% overall response rate in subjects with Sezary syndrome. We performed single-cell RNA-sequencing on samples collected before the first treatment and after 3 weeks of pembrolizumab treatment. Sequencing was performed on cryopreserved peripheral blood T-lymphocytes isolated from 6 trial participants, including 3 patients who responded to pembrolizumab treatment and 3 patients who did not respond. A total of 118,961 peripheral blood T-cells are included in this data set.