DS3201-324

• Research type

  Research Study

• Full title

  A PHASE 1B, MULTICENTER, OPEN-LABEL STUDY OF VALEMETOSTAT TOSYLATE IN COMBINATION WITH DXd ADCs IN SUBJECTS WITH SOLID TUMORS (STUDY OF VALEMETOSTAT IN COMBINATION WITH DXd ADCs) [SUB-PROTOCOL A: VALEMETOSTAT TOSYLATE IN COMBINATION WITH TRASTUZUMAB DERUXTECAN IN SUBJECTS WITH HER2-LOW, UNRESECTABLE AND/OR METASTATIC BREAST CANCER] [SUB-PROTOCOL B: VALEMETOSTAT TOSYLATE IN COMBINATION WITH T-DXd IN SUBJECTS WITH PREVIOUSLY TREATED ADVANCED OR METASTATIC HER2-POSITIVE GASTRIC OR GASTRO-ESOPHAGEAL JUNCTION ADENOCARCINOMA] [SUB-PROTOCOL C: VALEMETOSTAT TOSYLATE IN COMBINATION WITH DATO-DXD IN SUBJECTS WITH PREVIOUSLY TREATED, LOCALLY ADVANCED, UNRESECTABLE, OR METASTATIC NON-SQUAMOUS NON-SMALL CELL LUNG CANCER WITH OR WITHOUT ACTIONABLE GENOMIC ALTERATIONS]

• IRAS ID

  1011830

• Contact name

  Bettina Steffens

• Contact email

  TBEU-clinicaltrials@daiichi-sankyo.eu

• Sponsor organisation

  Daiichi Sankyo Europe GmbH

• Clinicaltrials.gov Identifier

  NCT06244485

• Research summary

  This trial is a Phase 1b, global, multicenter, open-label, 2-part trial of valemetostat in combination with DXd ADCs in subjects with solid tumour. The Master Protocol trial design contains 3 independent subprotocols (DS3201-324A, DS3201-324B, and DS3201-324C), which have been defined by treatment combination and cancer type. The estimated number of total participants for this trial is approximately 210.
   Subprotocol A: Breast cancer, approximately 70 participants will receive Valemetostat in combination with T-DXd
   Subprotocol B: Gastric cancer, approximately 70 participants will receive Valemetostat in combination with T-DXd
   Subprotocol C: Non-small cell lung cancer, approximately 70 participants will receive Valemetostat in combination with Dato-DXd. The protocol is composed of two parts. The primary objective of the Part 1 Dose-escalation Phase is to determine the maximum tolerated dose (MTD). The Safety Review Committee (SRC) composed of investigators
  and the Sponsor will be responsible for overseeing the safety of the dose-escalation/de-escalation and deciding the next dose level based on review of all safety data, as appropriate. Only 1 dose, less than or at the MTD, may be selected by the SRC for each treatment combination for further evaluation in the Part 2 Dose-expansion Phase. Primary objective in Part 2 Dose expansion phase is to further evaluate the safety and efficacy of combination.

• REC name

  South Central - Oxford A Research Ethics Committee

• REC reference

  25/SC/0143

• Date of REC Opinion

  16 Jul 2025

• REC opinion

  Further Information Favourable Opinion