Eisai Submits New Drug Application in Japan for DENILEUKIN DIFTITOX (Recombinant) for Relapsed or Refractory CTCL and PTCL

TOKYO, April 8, 2020 /PRNewswire/ --Eisai Co., Ltd. (Headquarters: Tokyo; CEO: Haruo Naito; “Eisai”) recently announced that it has submitted a marketing authorization application in Japan for DENILEUKIN DIFTITOX (recombinant) (generic name; development code: E7777) for the treatment of relapsed or refractory cutaneous T-cell lymphoma (CTCL) and peripheral T-cell lymphoma (PTCL).

This application is based on data from a multicenter, open-label, single-arm Phase II clinical study (Study 205) conducted in Japan in patients with relapsed or refractory CTCL or PTCL, which evaluated the efficacy and safety of the drug.

This study met the primary endpoint, surpassing the prespecified threshold with statistical significance: the objective response rate (ORR) in patients with CTCL and PTCL (n = 36) was 36.1%.%（95%Confidence interval (CI): 20.8–53.8). For patients with CTCL subtypes (n = 19), the ORR was 31.6%（95%CI: 12.6-56.6); for patients with PTCL subtypes (n = 17), the ORR was 41.2%%（95%CI：18.4-67.1）。

The five most common adverse events observed in this study were elevated aspartate aminotransferase (AST) levels (89.2%), elevated alanine aminotransferase (ALT) (86.5%), hypoalbuminemia (70.3%), lymphopenia (70.3%), and fever (51.4%).

Denileukin diftitox (recombinant) is a fusion protein of interleukin-2 (IL-2) and the receptor-binding domain of diphtheria toxin, which specifically binds to IL-2 receptors on the surface of tumor lymphocytes. The antitumor effect of denileukin diftitox depends on the intracellular delivery of diphtheria toxin, which inhibits protein synthesis and induces cell death. This drug has been evaluated by the "Study Group on Unapproved Drugs/Off-label Drugs with High Medical Needs" as a drug with high medical needs, and the Ministry of Health, Labour and Welfare has requested Eisai to develop this drug.

Eisai positions oncology as a key therapeutic area, aiming to discover revolutionary new drugs with the potential to cure cancer. We seek to further meet the diverse needs of cancer patients, their families, and healthcare providers, contributing to the enhancement of their well-being.