A Phase 1 interventional study of Nemtabrutinib in Mature B-cell Neoplasms, sponsored by Merck Sharp & Dohme LLC. Completed at 7 sites in Japan. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-05-13.
Sponsored by Merck Sharp & Dohme LLC · Phase 1, Interventional, and Treatment
The purpose of this study was to evaluate the safety, tolerability, pharmacokinetics (PK), and preliminary efficacy of nemtabrutinib in Japanese participants with mature B-cell neoplasms.
Merck Sharp & Dohme LLC is the lead sponsor of 2,114 studies on the registry; 133 are open to participants now.
Of its 489 completed or terminated interventional studies of FDA-regulated products, 362 (74%) have results posted.
Counted across the registry records on this site, refreshed daily.
The main inclusion and exclusion criteria include but are not limited to the following:
Inclusion Criteria:
Histologically confirmed B-cell malignancy:
Exclusion Criteria:
Participants receive nemtabrutinib at specified dose orally once daily (QD) until progressive disease (PD) or discontinuation
Drug: Nemtabrutinib
Nemtabrutinib tablets will be administered orally QD at dosage of 45 mg or 65 mg
Also known as: MK-1026, ARQ 531
Number of Participants Who Experience Dose Limiting Toxicities (DLTs) Per National Cancer Institute Common Terminology Criteria for Adverse Events (NCI-CTCAE) Version 5.0
A DLT is ≥1 of: Grade ≥3 nonhematologic toxicity with exception of Grade 3 nausea, vomiting, diarrhea, rash, fatigue, and uncontrolled hypertension lasting \>72 hours despite optimal supportive case; Grade 4 hematologic toxicity lasting \>7 days, Grade 4 platelet count decreased of any duration (with exceptions), or Grade 3 platelet count decreased with bleeding (with exceptions), or Grade 3 or higher febrile neutropenia of any duration; Grade 3 or Grade 4 nonhematologic laboratory abnormality, if results in drug induced liver injury (DILI), or medical intervention is required, or the abnormality leads to hospitalization, or the abnormality persists for \>1 week (with exceptions); missing \>25% of nemtabrutinib doses as a result of drug-related AE(s); Grade 5 toxicity. Toxicities will be graded using NCI-CTCAE version 5.0 except hematologic toxicities in participants with chronic lymphocytic leukemia (CLL) assessed according to the International Workshop on CLL (iwCLL) criteria.
Time frame: Up to approximately 4 weeks
Number of Participants Who Experience Adverse Events (AEs)
An AE is any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention.
Time frame: Up to approximately 26 months
Number of Participants Discontinuing Study Treatment Due to AEs
An AE is any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention.
Time frame: Up to approximately 26 months
Area Under the Curve From Dosing to 24 Hours Postdose (AUC0-24) of Nemtabrutinib
AUC0-24 is the area under the curve of plasma concentration of nemtabrutinib from dosing to 24 hours postdose.
Time frame: Day 1: Pre-dose and 1, 2, 4, 6, 8, 10, and 24 hours post-dose
Minimum Concentration (Cmin) of Nemtabrutinib
Cmin is the lowest observed plasma concentration.
Time frame: Day 1: Pre-dose and 1, 2, 4, 6, 8, 10, and 24 hours post-dose
Maximum Concentration (Cmax) of Nemtabrutinib
Cmax is the lowest observed plasma concentration.
Time frame: Day 1: Pre-dose and 1, 2, 4, 6, 8, 10, and 24 hours post-dose
Time to Maximum Concentration (Tmax) of Nemtabrutinib
Tmax is the time to reach Cmax.
Time frame: Day 1: Pre-dose and 1, 2, 4, 6, 8, 10, and 24 hours post-dose
Objective Response Rate (ORR) as Assessed by Investigator
ORR is the proportion of participants in the analysis population with objective response. Objective response is defined as participants who achieve at least a partial response (PR) per disease-specific criteria as assessed by investigator. Data are presented separately for participants with chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL) and non-CLL/SLL participants.
Time frame: Up to approximately 26 months
Duration of Response (DOR) as Assessed by Investigator
For participants who demonstrate an objective response as assessed by investigator, per disease-specific criteria, duration of response is defined as the time from the first documented evidence of an objective response until disease progression or death due to any cause, whichever occurs first.
Time frame: Up to approximately 26 months
| Milestone | Nemtabrutinib 45 mg | Nemtabrutinib 65 mg QD |
|---|---|---|
| Started | 3 | 4 |
| Completed | 0 | 0 |
| Not completed | 3 | 4 |
| Withdrew: Death | 3 | 3 |
| Withdrew: Sponsor decision | 0 | 1 |
AUC0-24 is the area under the curve of plasma concentration of nemtabrutinib from dosing to 24 hours postdose.
| hr*ng/mL | Nemtabrutinib 45 mg | Nemtabrutinib 65 mg |
|---|---|---|
| Area Under the Curve From Dosing to 24 Hours Postdose (AUC0-24) of Nemtabrutinib | 8000 (5470 to 11700) | 9890 (7120 to 13700) |
Cmin is the lowest observed plasma concentration.
| ng/mL | Nemtabrutinib 45 mg | Nemtabrutinib 65 mg |
|---|---|---|
| Minimum Concentration (Cmin) of Nemtabrutinib | 190 (105 to 346) | 218 (130 to 366) |
Cmax is the lowest observed plasma concentration.
| ng/mL | Nemtabrutinib 45 mg | Nemtabrutinib 65 mg |
|---|---|---|
| Maximum Concentration (Cmax) of Nemtabrutinib | 638 (454 to 895) | 917 (638 to 1230) |
Tmax is the time to reach Cmax.
| Hours | Nemtabrutinib 45 mg | Nemtabrutinib 65 mg |
|---|---|---|
| Time to Maximum Concentration (Tmax) of Nemtabrutinib | 1.88 (0.92 to 1.90) | 1.43 (0.92 to 1.92) |
ORR is the proportion of participants in the analysis population with objective response. Objective response is defined as participants who achieve at least a partial response (PR) per disease-specific criteria as assessed by investigator. Data are presented separately for participants with chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL) and non-CLL/SLL participants.
| Percentage of Participants | Nemtabrutinib 45 mg | Nemtabrutinib 65 mg |
|---|---|---|
| CLL/SLL | 100.0 (2.5 to 100.0) | 100.0 (2.5 to 100.0) |
| non-CLL/SLL | 0.0 (0.0 to 84.2) | 0.0 (0.0 to 70.8) |
A DLT is ≥1 of: Grade ≥3 nonhematologic toxicity with exception of Grade 3 nausea, vomiting, diarrhea, rash, fatigue, and uncontrolled hypertension lasting \>72 hours despite optimal supportive case; Grade 4 hematologic toxicity lasting \>7 days, Grade 4 platelet count decreased of any duration (with exceptions), or Grade 3 platelet count decreased with bleeding (with exceptions), or Grade 3 or higher febrile neutropenia of any duration; Grade 3 or Grade 4 nonhematologic laboratory abnormality, if results in drug induced liver injury (DILI), or medical intervention is required, or the abnormality leads to hospitalization, or the abnormality persists for \>1 week (with exceptions); missing \>25% of nemtabrutinib doses as a result of drug-related AE(s); Grade 5 toxicity. Toxicities will be graded using NCI-CTCAE version 5.0 except hematologic toxicities in participants with chronic lymphocytic leukemia (CLL) assessed according to the International Workshop on CLL (iwCLL) criteria.
| Participants | Nemtabrutinib 45 mg | Nemtabrutinib 65 mg |
|---|---|---|
| Number of Participants Who Experience Dose Limiting Toxicities (DLTs) Per National Cancer Institute Common Terminology Criteria for Adverse Events (NCI-CTCAE) Version 5.0 | 0 | 0 |
An AE is any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention.
| Participants | Nemtabrutinib 45 mg | Nemtabrutinib 65 mg |
|---|---|---|
| Number of Participants Who Experience Adverse Events (AEs) | 3 | 4 |
An AE is any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention.
| Participants | Nemtabrutinib 45 mg | Nemtabrutinib 65 mg |
|---|---|---|
| Number of Participants Discontinuing Study Treatment Due to AEs | 0 | 0 |
For participants who demonstrate an objective response as assessed by investigator, per disease-specific criteria, duration of response is defined as the time from the first documented evidence of an objective response until disease progression or death due to any cause, whichever occurs first.
| Months | Nemtabrutinib 45 mg | Nemtabrutinib 65 mg |
|---|---|---|
| Duration of Response (DOR) as Assessed by Investigator | NA (NA to NA) | NA (NA to NA) |
Collected over Up to ~26 months. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Nemtabrutinib 45 mg | 3/3 (100%) | 1/3 (33.3%) | 3/3 (100%) |
| Nemtabrutinib 65 mg | 3/4 (75%) | 1/4 (25%) | 4/4 (100%) |
| Event | Nemtabrutinib 45 mg | Nemtabrutinib 65 mg |
|---|---|---|
| MyelosuppressionBlood and lymphatic system disorders | 1/3 | 0/4 |
| Infusion related reactionInjury, poisoning and procedural complications | 1/3 | 0/4 |
| Tumour lysis syndromeMetabolism and nutrition disorders | 1/3 | 0/4 |
| Interstitial lung diseaseRespiratory, thoracic and mediastinal disorders | 0/3 | 1/4 |
| Event | Nemtabrutinib 45 mg | Nemtabrutinib 65 mg |
|---|---|---|
| ConstipationGastrointestinal disorders | 3/3 | 1/4 |
| Platelet count decreasedInvestigations | 2/3 | 0/4 |
| Oedema peripheralGeneral disorders | 0/3 | 2/4 |
| DysgeusiaNervous system disorders | 0/3 | 2/4 |
| LeukopeniaBlood and lymphatic system disorders | 1/3 | 0/4 |
| NeutropeniaBlood and lymphatic system disorders | 1/3 | 0/4 |
| ThrombocytopeniaBlood and lymphatic system disorders | 1/3 | 0/4 |
| NauseaGastrointestinal disorders | 1/3 | 0/4 |
| MalaiseGeneral disorders | 1/3 | 0/4 |
| PneumoniaInfections and infestations | 1/3 | 0/4 |
| Age, Continuous(Years) | Nemtabrutinib 45 mg | Nemtabrutininb 65 mg | Total |
|---|---|---|---|
| Mean | 71.3 ± 14.4 | 69.8 ± 11.0 | 70.4 ± 11.4 |
| Sex: Female, Male(Participants) | Nemtabrutinib 45 mg | Nemtabrutininb 65 mg | Total |
|---|---|---|---|
| Female | 1 | 1 | 2 |
| Male | 2 | 3 | 5 |
| Ethnicity (NIH/OMB)(Participants) | Nemtabrutinib 45 mg | Nemtabrutininb 65 mg | Total |
|---|---|---|---|
| Hispanic or Latino | 0 | 0 | 0 |
| Not Hispanic or Latino | 3 | 4 | 7 |
| Unknown or Not Reported | 0 | 0 | 0 |
| Race (NIH/OMB)(Participants) | Nemtabrutinib 45 mg | Nemtabrutininb 65 mg | Total |
|---|---|---|---|
| American Indian or Alaska Native | 0 | 0 | 0 |
| Asian | 3 | 4 | 7 |
| Native Hawaiian or Other Pacific Islander | 0 | 0 | 0 |
| Black or African American | 0 | 0 | 0 |
| White | 0 | 0 | 0 |
| More than one race | 0 | 0 | 0 |
| Unknown or Not Reported | 0 | 0 | 0 |
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