Otsuka Pharmaceutical Co., Ltd.

March 22, 2021

Otsuka Has Filed an Application in Japan for Regulatory Approval of OPC-61815, a V2 -Receptor Antagonist for the Treatment of Cardiac Edema

Otsuka Pharmaceutical Co., Ltd. (Otsuka) announces that an NDA (New Drug Application) has been submitted to the Pharmaceuticals and Medical Devices Agency in Japan to seek manufacturing and marketing approval of OPC-61815 for the treatment of cardiac edema.

OPC-61815 is a prodrug of oral tolvaptan (tolvaptan sodium phosphate). A prodrug is a medication that is converted into an active drug in the human body following administration. Tolvaptan, discovered by Otsuka, is a novel compound that is as an orally available antagonist of the vasopressin V2-receptor. It inhibits water reabsorption at the renal collecting duct, thereby enhancing water diuresis (aquaresis) without depletion of electrolytes.

In non-clinical studies OPC-61815 has been rapidly hydrolyzed to tolvaptan after intravenous administration, and shown effects. In the clinical phase 3 trial in Japan, the efficacy and safety of this compound were compared with 15 mg tolvaptan tablets in 294 patients with cardiac edema.

The phase 3 trial outcomes showed non-inferiority of OPC-61815 versus tolvaptan 15mg tablet in the primary endpoint of change in body weight from baseline at the final dose. In addition, the main secondary endpoints were not significantly different from tolvaptan tablets. No safety issues were identified during the trial.

If this drug candidate is approved for use, as an intravenous diuretic it would provide a new treatment option for patients with cardiac edema who cannot take tolvaptan orally.