NCT06244485
A Study of Valemetostat Tosylate in Combination With DXd ADCs in Subjects With Solid Tumors
Active, Not Recruiting
PHASE1Ages 18+InterventionalTreatmentDaiichi Sankyo
~98 participants
Updated 2026-07-21 on ClinicalTrials.gov
What's tested:Valemetostat tosylateT-DXdDato-DXd
At a glance
Recruiting sites
0 of 35 listed sites are recruiting right now
RecruitingSuspended, closed, or not yet open
What they're measuring
Number of Participants Reporting Dose-limiting Toxicities (Part 1 Dose Escalation)
Measured over Cycle 1 Day 1 up to Day 21 (each cycle is 21 days)
+2 more outcomes measured
Conditions
Where it's being run
35 sites across 16 statesJapan10
China7
Texas3
California2
New York2
Florida1
Hawaii1
Illinois1
Study leadership
- Global Clinical Leader · STUDY_DIRECTOR · Daiichi Sankyo
Who to contact
This trial hasn't published a contact. View it on ClinicalTrials.gov
Do you actually qualify for this trial?
Add a private profile and we'll compare every criterion below against your situation — and tell you which ones are met, uncertain, or excluding.
Eligibility criteria
Inclusion
At least 18 years or the minimum legal adult age (whichever is greater) at the time the ICF is signed.
Has at least 1 measurable lesion based on investigator imaging assessment (computed tomography or magnetic resonance imaging) using RECIST v 1.1 at Screening.
Is willing to provide an adequate tumor sample.
Eastern Cooperative Oncology Group performance status (ECOG PS) of 0 or 1 at Screening.
Diagnosed with pathologically documented breast cancer that:
Pathologically documented Stage IIIB, IIIC, or IV non-squamous NSCLC with or without AGA at the time of enrollment.
Must meet prior therapy requirements:
Participants without AGA: (a) received platinum-based chemotherapy in combination with α-PD-1/α -PD-L1 mAb as a prior line of therapy or (b) received platinum-based chemotherapy and α -PD-1/ α -PD-L1 mAb (in either order) sequentially as 2 prior lines of therapy.
Participants with AGA: (a) has been treated with at least 1 or 2 prior lines of applicable targeted therapy that is locally approved for participant's genomic alteration at the time of Screening, (b) participants who have received platinum-based chemotherapy as a prior line of cytotoxic therapy, (c) may have received α -PD-1/α -PD-L1 mAb alone or in combination with a cytotoxic agent
Exclusion
Has previously been treated with any enhancer of zeste homolog inhibitors.
Uncontrolled or significant cardiovascular disease.
Has spinal cord compression or clinically active central nervous system metastases, defined as untreated and symptomatic, or requiring therapy with corticosteroids or anticonvulsants to control associated symptoms.
Has leptomeningeal carcinomatosis or metastasis.
Clinically severe pulmonary compromise resulting from intercurrent pulmonary illnesses.
Current use of moderate or strong cytochrome P450 (CYP)3A inducers.
Systemic treatment with corticosteroids (\>10 mg daily prednisone equivalents).
History of severe hypersensitivity reactions to other monoclonal antibodies (mAbs).
Evidence of ongoing uncontrolled systemic bacterial, fungal, or viral infection requiring treatment with intravenous (IV) antibiotics, antivirals, or antifungals.
Female who is pregnant or breastfeeding or intends to become pregnant during the study.
Psychological, social, familial, or geographical factors that would prevent regular follow-up.
Has previously received any anti-HER2 therapy in the metastatic setting.
Has received prior treatment with an antibody-drug conjugate that consists of an exatecan derivative that is a topoisomerase I inhibitor, including either as part of prior treatment history or within prior participation in a clinical study.
What this trial measures
- Number of Participants Reporting Dose-limiting Toxicities (Part 1 Dose Escalation)Cycle 1 Day 1 up to Day 21 (each cycle is 21 days)
- Number of Participants Reporting Treatment-emergent Adverse Events (Part 1 Dose Escalation)Screening up to 40 days after last dose
- Objective Response Rate Based on Investigator Assessment (Part 2 Dose Expansion)Baseline (Screening), at every 6 weeks from Cycle 1 Day 1 in the first year, and every 12 weeks thereafter until disease progression or until the start of a new anticancer treatment, up to approximately 5 years
Objective response rate (ORR) is defined as the proportion of participants with a best overall response of confirmed complete response (CR) or confirmed partial response (PR) according to RECIST v 1.1 criteria. CR is defined as a disappearance of all target lesions and PR is defined as at least a 30% decrease in the sum of diameters of target lesions.