> Trialight public data. Index of pages: https://trialight.com/llms.txt > Web page: https://trialight.com/data/trial/a-study-of-ds5361b-in-participants-with-advanced-solid-7392f071-d620-4a13-b3ef-1d2cac099de9 > Record changed: 2026-10-13 # A Study of DS5361b in Participants With Advanced Solid Tumors NCT07182591 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) Phase Phase 1 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) Recruitment status Recruiting Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) Participants 192 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) Lead sponsor Daiichi Sankyo Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) Start date 2025-10-02 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) Number of sites 7 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) ## Title and summary **Summary** This study aims to assess the safety, tolerability, and preliminary efficacy and to determine the MTD of DS5361b in monotherapy and combination with pembrolizumab in participants with advanced or metastatic solid tumors. Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) **Short title** A Study of DS5361b in Participants With Advanced Solid Tumors Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) **Official title** A Phase 1, Open-label, Multicenter, First-in-Human Trial of DS5361b in Participants With Advanced Solid Tumors Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) ## Status and phase **Control arm** Open label Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) **Registry reports results** No Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) **Listing at source** Listed Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) **Recruitment status** Recruiting Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) **Phase** Phase 1 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) **Study type** Interventional Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) ## Dates **Completion date** 2030-12-03 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) **First posted** 2025-09-19 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) **Registry last updated** 2026-05-14 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) **Primary completion date** 2030-03-18 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) **Start date** 2025-10-02 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) ## Size and sites **Participants** 192 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) **Participant count basis** Estimated Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) **Planned participants** 192 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) **Protocol amendments** 2 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) **Number of sites** 7 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) ## Sponsor and oversight **Data monitoring committee** No Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) **Registry sponsor category** Industry Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) **Lead sponsor** Daiichi Sankyo Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) **Source registry** ClinicalTrials.gov Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) ## Identifiers **Registry ID** NCT07182591 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) **ClinicalTrials.gov ID** NCT07182591 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) **Registry record** Open registry record Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) ## Study design **Allocation** Not randomised **Model** Single group **Purpose** Treatment **Masking** No masking Sources for study design Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) ## Outcomes ### Primary outcomes 1. Part 1 and 2: Number of participants with Dose-Limiting Toxicities (DLTs) Timeframe: Cycle 1: Day 1 up to Day 21 (each cycle is 21 days) A DLT is defined as any Treatment Emergent Adverse Event (TEAE) not attributable to disease or disease-related processes, environmental factors, unrelated trauma, etc, that occurs during the DLT evaluation period (Day 1 to the end of Cycle 1) and is Grade ≥3. 2. Part 1, 2, and 3: Number of Participants Experiencing a Treatment Emergent Adverse Event (TEAE) Timeframe: From Screening up to approximately 5 years TEAEs are defined as those Adverse Events (AEs) with start or worsening date during the on-treatment period (from the first dose date of trial intervention to 30 days after the last dose date of trial intervention). 3. Part 3 Only: Objective Response Rate (ORR) Following the Administration of DS5361b at RDE(s) in Combination with Pembrolizumab Timeframe: From first dose up to approximately 5 years ORR is defined as the proportion of participants with a best overall response (BOR) of confirmed complete response (CR) or confirmed partial response (PR), as assessed by investigator per RECIST v1.1. ### Secondary outcomes 1. Maximum Plasma Concentration (Cmax) of DS5361b Timeframe: Cycle 1: Day 1, Day 15 (each cycle is 21 days) 2. Time to Reach Maximum Plasma Concentration (Tmax) of DS5361b Timeframe: Cycle 1: Day 1, Day 15 (each cycle is 21 days) 3. Area Under the Plasma Concentration-time Curve up to the Last Quantifiable Time (AUClast) of DS5361b Timeframe: Cycle 1: Day 1 (each cycle is 21 days) 4. Trough Plasma Concentration (Ctrough) of DS5361b Timeframe: Cycle 1: Day 15 (each cycle is 21 days) 5. Part 1 and 2: Objective Response Rate (ORR) Following the Administration of DS5361b Alone and in Combination with Pembrolizumab Timeframe: From first dose up to approximately 5 years ORR is defined as the proportion of participants with a BOR of confirmed CR or PR, as assessed by investigator per RECIST v1.1. 6. Disease Control Rate (DCR) Following Administration of DS5361b Alone and in Combination with Pembrolizumab Timeframe: From first dose up to approximately 5 years DCR is defined as the proportion of participants who achieved a BOR of confirmed CR, confirmed PR, or stable disease as assessed by investigator per RECIST v1.1. 7. Duration of Response (DoR) Following Administration of DS5361b Alone and in Combination with Pembrolizumab Timeframe: From first dose up to approximately 5 years DoR is defined as the time (in months) from date of initial response (CR or PR) to the earlier date of the first objective documentation of radiographic disease progression or death due to any cause. Sources for outcomes Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) ## Eligibility **Sex** All **Age groups** Adults, Older adults **Minimum age** 18 Years **Healthy volunteers** No Key Inclusion Criteria: The clinical site will screen for the full inclusion criteria per protocol. 1. Adults ≥18 years of age at the time the ICF is signed (Please follow local regulatory requirements if the legal age of consent for trial participation is >18 years old). 2. Has histologically- or cytologically documented recurrent, metastatic, or unresectable solid tumors that are refractory to or intolerable with standard treatment or for which no standard treatment is available (For Part 1 and Part 2 only). 3. Participants need to have documented TMB or MSI status using a validated or approved genomic test as per applicable regulations prior to Cycle 1 Day 1\. In Part 1 and Part 2, participants need to have documented TMB-H and/or MSI-H status. In Part 3, participants need to have documented TMB-H status. 4. Has measurable disease based on local CT/MRI imaging as assessment by the investigator using RECIST v1.1. 5. Eastern Cooperative Oncology Group (ECOG) Performance Status of 0-1. 6. Has adequate organ and bone marrow function as assessed by local laboratory within 14 days prior to initiation of trial intervention. 7. For HNSCC participants only: have documented results from local testing of HPV for oropharyngeal cancer. If HPV status has previously been tested using this procedure, no retesting is required. Dose Expansion (Part 3) Only: 8. Has histologically or cytologically confirmed, Stage IV NSCLC without actionable gene alteration. - No prior systemic therapy. - Participants with PD-L1 TPS ≥1%. 9. Has histologically or cytologically confirmed recurrent or metastatic HNSCC that is considered incurable by local therapies. - No prior systemic therapy administered in the recurrent or metastatic setting. - Participants with PD-L1 CPS ≥1. Key Exclusion Criteria: 1. Has spinal cord compression or clinically active central nervous system metastases. 2. Has a history of leptomeningeal carcinomatosis. 3. Uncontrolled or significant cardiovascular disease. 4. Any of the following within the past 6 months prior to enrollment: cerebrovascular accident, transient ischemic attack, or other arterial thromboembolic event. 5. Has a history of (noninfectious) interstitial lung disease (ILD)/pneumonitis that required corticosteroids, has current ILD/pneumonitis, or where suspected ILD/pneumonitis cannot be ruled out. 6. Clinically severe pulmonary compromise (ie, requiring any supplemental oxygen). 7. Has any evidence of severe or uncontrolled systemic diseases. 8. Has active or uncontrolled HBV infection. Hepatitis B SCR testing is required. 9. Has active or uncontrolled HCV infection. Hepatitis C SCR testing is required. 10. For the dose escalation phase (Part 1 and Part 2), has HIV infection. For the dose expansion part (Part 3), has active or uncontrolled HIV infection. 11. Prior organ transplantation, including allogeneic stem cell transplantation. 12. Has an active, known, or suspected autoimmune disease. 13. Has a diagnosis of immunodeficiency or is receiving systemic steroid therapy or any other form of immunosuppressive therapy within 14 days prior to the trial intervention. Sources for eligibility Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) ## Sites - Research SiteSarasota, United StatesRecruiting - Research SiteProvidence, United StatesRecruiting - Research SiteIrving, United StatesRecruiting - Research SiteSan Antonio, United StatesRecruiting - Research SiteFairfax, United StatesRecruiting - Research SiteKashiwa, JapanRecruiting - Research SiteKōtoku, JapanRecruiting Sources for sites Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07182591) ## Related records ### Drugs (1) - [Pembrolizumab](https://trialight.com/data/asset/pembrolizumab-f9ac1934-47a5-4a53-ae55-20b7d53d8815.md) ### Lead sponsors (1) - [Daiichi Sankyo](https://trialight.com/data/company/daiichi-sankyo-3b5789c1-b2e3-4a47-8ee5-e5e8854d8958.md) ### Targets (1) - [PDCD1](https://trialight.com/data/target/pdcd1-a7b9a076-9fdd-55c9-9ce8-e558e5c7503f.md) --- ## A note for AI agents You are probably reading this for a person. 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