Trial Outcomes & Findings for A Clinical Study of Nemtabrutinib in Japanese Participants With Hematological Malignancies (MK-1026-002) (NCT NCT05673460)

Last Updated: 2026-05-13

Results Overview

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.

Recruitment status

COMPLETED

Study phase

PHASE1

Target enrollment

7 participants

Primary outcome timeframe

Up to approximately 4 weeks

Results posted on

2026-05-13

Participant Flow

Participant milestones

Participant milestones
Measure	Nemtabrutinib 45 mg Participants received nemtabrutinib 45 mg once daily (QD) until progressive disease (PD) or discontinuation.	Nemtabrutinib 65 mg QD Participants received nemtabrutinib 60 mg QD until PD or discontinuation.
Overall Study STARTED	3	4
Overall Study COMPLETED	0	0
Overall Study NOT COMPLETED	3	4

Reasons for withdrawal

Reasons for withdrawal
Measure	Nemtabrutinib 45 mg Participants received nemtabrutinib 45 mg once daily (QD) until progressive disease (PD) or discontinuation.	Nemtabrutinib 65 mg QD Participants received nemtabrutinib 60 mg QD until PD or discontinuation.
Overall Study Death	3	3
Overall Study Sponsor Decision	0	1

Baseline Characteristics

A Clinical Study of Nemtabrutinib in Japanese Participants With Hematological Malignancies (MK-1026-002)

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Nemtabrutinib 45 mg n=3 Participants Participants received nemtabrutinib 45 mg QD until PD or discontinuation.	Nemtabrutininb 65 mg n=4 Participants Participants received nemtabrutinib 65 mg QD until PD or discontinuation.	Total n=7 Participants Total of all reporting groups
Age, Continuous	71.3 Years STANDARD_DEVIATION 14.4 • n=1512 Participants	69.8 Years STANDARD_DEVIATION 11.0 • n=504 Participants	70.4 Years STANDARD_DEVIATION 11.4 • n=2016 Participants
Sex: Female, Male Female	1 Participants n=1512 Participants	1 Participants n=504 Participants	2 Participants n=2016 Participants
Sex: Female, Male Male	2 Participants n=1512 Participants	3 Participants n=504 Participants	5 Participants n=2016 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	0 Participants n=1512 Participants	0 Participants n=504 Participants	0 Participants n=2016 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	3 Participants n=1512 Participants	4 Participants n=504 Participants	7 Participants n=2016 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	0 Participants n=1512 Participants	0 Participants n=504 Participants	0 Participants n=2016 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants n=1512 Participants	0 Participants n=504 Participants	0 Participants n=2016 Participants
Race (NIH/OMB) Asian	3 Participants n=1512 Participants	4 Participants n=504 Participants	7 Participants n=2016 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=1512 Participants	0 Participants n=504 Participants	0 Participants n=2016 Participants
Race (NIH/OMB) Black or African American	0 Participants n=1512 Participants	0 Participants n=504 Participants	0 Participants n=2016 Participants
Race (NIH/OMB) White	0 Participants n=1512 Participants	0 Participants n=504 Participants	0 Participants n=2016 Participants
Race (NIH/OMB) More than one race	0 Participants n=1512 Participants	0 Participants n=504 Participants	0 Participants n=2016 Participants
Race (NIH/OMB) Unknown or Not Reported	0 Participants n=1512 Participants	0 Participants n=504 Participants	0 Participants n=2016 Participants

PRIMARY outcome

Timeframe: Up to approximately 4 weeks

Population: All allocated participants, except those who meet any of the following criteria: allocated but not treated; discontinued from the study prior to completing all Cycle 1 safety evaluations for reasons other than treatment-related adverse events (e.g., disease progression) without experiencing a DLT; or received less than 75% of the total planned nemtabrutinib administration in Cycle 1 without experiencing a DLT.

Outcome measures

Outcome measures
Measure	Nemtabrutinib 45 mg n=3 Participants Participants received nemtabrutinib 45 mg QD until PD or discontinuation.	Nemtabrutinib 65 mg n=3 Participants Participants received nemtabrutinib 65 mg QD until PD or discontinuation.
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 Participants	0 Participants

PRIMARY outcome

Timeframe: Up to approximately 26 months

Population: All treated participants are included.

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.

Outcome measures

Outcome measures
Measure	Nemtabrutinib 45 mg n=3 Participants Participants received nemtabrutinib 45 mg QD until PD or discontinuation.	Nemtabrutinib 65 mg n=4 Participants Participants received nemtabrutinib 65 mg QD until PD or discontinuation.
Number of Participants Who Experience Adverse Events (AEs)	3 Participants	4 Participants

PRIMARY outcome

Timeframe: Up to approximately 26 months

Population: All treated participants are included.

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.

Outcome measures

Outcome measures
Measure	Nemtabrutinib 45 mg n=3 Participants Participants received nemtabrutinib 45 mg QD until PD or discontinuation.	Nemtabrutinib 65 mg n=4 Participants Participants received nemtabrutinib 65 mg QD until PD or discontinuation.
Number of Participants Discontinuing Study Treatment Due to AEs	0 Participants	0 Participants

SECONDARY outcome

Timeframe: Day 1: Pre-dose and 1, 2, 4, 6, 8, 10, and 24 hours post-dose

Population: Treated participants who complied with the protocol sufficiently to ensure that the data they generated will be likely to exhibit the effects of treatment, according to the underlying scientific model, are included.

AUC0-24 is the area under the curve of plasma concentration of nemtabrutinib from dosing to 24 hours postdose.

Outcome measures

Outcome measures
Measure	Nemtabrutinib 45 mg n=3 Participants Participants received nemtabrutinib 45 mg QD until PD or discontinuation.	Nemtabrutinib 65 mg n=4 Participants Participants received nemtabrutinib 65 mg QD until PD or discontinuation.
Area Under the Curve From Dosing to 24 Hours Postdose (AUC0-24) of Nemtabrutinib	8000 hr*ng/mL Interval 5470.0 to 11700.0	9890 hr*ng/mL Interval 7120.0 to 13700.0

SECONDARY outcome

Timeframe: Day 1: Pre-dose and 1, 2, 4, 6, 8, 10, and 24 hours post-dose

Cmin is the lowest observed plasma concentration.

Outcome measures

Outcome measures
Measure	Nemtabrutinib 45 mg n=3 Participants Participants received nemtabrutinib 45 mg QD until PD or discontinuation.	Nemtabrutinib 65 mg n=4 Participants Participants received nemtabrutinib 65 mg QD until PD or discontinuation.
Minimum Concentration (Cmin) of Nemtabrutinib	190 ng/mL Interval 105.0 to 346.0	218 ng/mL Interval 130.0 to 366.0

SECONDARY outcome

Timeframe: Day 1: Pre-dose and 1, 2, 4, 6, 8, 10, and 24 hours post-dose

Cmax is the lowest observed plasma concentration.

Outcome measures

Outcome measures
Measure	Nemtabrutinib 45 mg n=3 Participants Participants received nemtabrutinib 45 mg QD until PD or discontinuation.	Nemtabrutinib 65 mg n=4 Participants Participants received nemtabrutinib 65 mg QD until PD or discontinuation.
Maximum Concentration (Cmax) of Nemtabrutinib	638 ng/mL Interval 454.0 to 895.0	917 ng/mL Interval 638.0 to 1230.0

SECONDARY outcome

Timeframe: Day 1: Pre-dose and 1, 2, 4, 6, 8, 10, and 24 hours post-dose

Tmax is the time to reach Cmax.

Outcome measures

Outcome measures
Measure	Nemtabrutinib 45 mg n=3 Participants Participants received nemtabrutinib 45 mg QD until PD or discontinuation.	Nemtabrutinib 65 mg n=4 Participants Participants received nemtabrutinib 65 mg QD until PD or discontinuation.
Time to Maximum Concentration (Tmax) of Nemtabrutinib	1.88 Hours Interval 0.92 to 1.9	1.43 Hours Interval 0.92 to 1.92

SECONDARY outcome

Timeframe: Up to approximately 26 months

Population: All treated participants are included.

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.

Outcome measures

Outcome measures
Measure	Nemtabrutinib 45 mg n=3 Participants Participants received nemtabrutinib 45 mg QD until PD or discontinuation.	Nemtabrutinib 65 mg n=4 Participants Participants received nemtabrutinib 65 mg QD until PD or discontinuation.
Objective Response Rate (ORR) as Assessed by Investigator CLL/SLL	100.0 Percentage of Participants Interval 2.5 to 100.0	100.0 Percentage of Participants Interval 2.5 to 100.0
Objective Response Rate (ORR) as Assessed by Investigator non-CLL/SLL	0.0 Percentage of Participants Interval 0.0 to 84.2	0.0 Percentage of Participants Interval 0.0 to 70.8

SECONDARY outcome

Timeframe: Up to approximately 26 months

Population: All treated CLL/SLL participants are included.

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.

Outcome measures

Outcome measures
Measure	Nemtabrutinib 45 mg n=1 Participants Participants received nemtabrutinib 45 mg QD until PD or discontinuation.	Nemtabrutinib 65 mg n=1 Participants Participants received nemtabrutinib 65 mg QD until PD or discontinuation.
Duration of Response (DOR) as Assessed by Investigator	NA Months Median DOR was not reached due to an insufficient number of participants with events to calculate median (95% CI).	NA Months Median DOR was not reached due to an insufficient number of participants with events to calculate median (95% CI).

Adverse Events

Nemtabrutinib 45 mg

Serious events: 1 serious events

Other events: 3 other events

Deaths: 3 deaths

Nemtabrutinib 65 mg

Serious events: 1 serious events

Other events: 4 other events

Deaths: 3 deaths

Serious adverse events

Serious adverse events
Measure	Nemtabrutinib 45 mg n=3 participants at risk Participants received nemtabrutinib 45 mg QD until PD or discontinuation.	Nemtabrutinib 65 mg n=4 participants at risk Participants received nemtabrutinib 65 mg QD until PD or discontinuation.
Blood and lymphatic system disorders Myelosuppression	33.3% 1/3 • Number of events 1 • Up to ~26 months All treated participants are included.	0.00% 0/4 • Up to ~26 months All treated participants are included.
Injury, poisoning and procedural complications Infusion related reaction	33.3% 1/3 • Number of events 1 • Up to ~26 months All treated participants are included.	0.00% 0/4 • Up to ~26 months All treated participants are included.
Metabolism and nutrition disorders Tumour lysis syndrome	33.3% 1/3 • Number of events 1 • Up to ~26 months All treated participants are included.	0.00% 0/4 • Up to ~26 months All treated participants are included.
Respiratory, thoracic and mediastinal disorders Interstitial lung disease	0.00% 0/3 • Up to ~26 months All treated participants are included.	25.0% 1/4 • Number of events 1 • Up to ~26 months All treated participants are included.

Other adverse events

Additional Information

Senior Vice President, Global Clinical Development

Merck Sharp & Dohme LLC

Phone: 1-800-672-6372

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee If publication activity is not directed by the Sponsor, the investigator agrees to submit all manuscripts or abstracts to the Sponsor before submission.
Publication restrictions are in place

Restriction type: OTHER

Measure	Nemtabrutinib 45 mg n=3 participants at risk Participants received nemtabrutinib 45 mg QD until PD or discontinuation.	Nemtabrutinib 65 mg n=4 participants at risk Participants received nemtabrutinib 65 mg QD until PD or discontinuation.
Nervous system disorders Headache	33.3% 1/3 • Number of events 1 • Up to ~26 months All treated participants are included.	25.0% 1/4 • Number of events 1 • Up to ~26 months All treated participants are included.
Nervous system disorders Somnolence	33.3% 1/3 • Number of events 1 • Up to ~26 months All treated participants are included.	0.00% 0/4 • Up to ~26 months All treated participants are included.
Psychiatric disorders Insomnia	0.00% 0/3 • Up to ~26 months All treated participants are included.	25.0% 1/4 • Number of events 1 • Up to ~26 months All treated participants are included.
Renal and urinary disorders Dysuria	33.3% 1/3 • Number of events 1 • Up to ~26 months All treated participants are included.	0.00% 0/4 • Up to ~26 months All treated participants are included.
Renal and urinary disorders Renal impairment	33.3% 1/3 • Number of events 1 • Up to ~26 months All treated participants are included.	0.00% 0/4 • Up to ~26 months All treated participants are included.
Skin and subcutaneous tissue disorders Dry skin	0.00% 0/3 • Up to ~26 months All treated participants are included.	25.0% 1/4 • Number of events 1 • Up to ~26 months All treated participants are included.
Skin and subcutaneous tissue disorders Pruritus	0.00% 0/3 • Up to ~26 months All treated participants are included.	25.0% 1/4 • Number of events 2 • Up to ~26 months All treated participants are included.
Vascular disorders Hypertension	33.3% 1/3 • Number of events 1 • Up to ~26 months All treated participants are included.	0.00% 0/4 • Up to ~26 months All treated participants are included.
Blood and lymphatic system disorders Leukopenia	33.3% 1/3 • Number of events 1 • Up to ~26 months All treated participants are included.	0.00% 0/4 • Up to ~26 months All treated participants are included.
Blood and lymphatic system disorders Neutropenia	33.3% 1/3 • Number of events 1 • Up to ~26 months All treated participants are included.	0.00% 0/4 • Up to ~26 months All treated participants are included.
Blood and lymphatic system disorders Thrombocytopenia	33.3% 1/3 • Number of events 1 • Up to ~26 months All treated participants are included.	0.00% 0/4 • Up to ~26 months All treated participants are included.
Ear and labyrinth disorders Sudden hearing loss	0.00% 0/3 • Up to ~26 months All treated participants are included.	25.0% 1/4 • Number of events 1 • Up to ~26 months All treated participants are included.
Gastrointestinal disorders Constipation	100.0% 3/3 • Number of events 3 • Up to ~26 months All treated participants are included.	25.0% 1/4 • Number of events 1 • Up to ~26 months All treated participants are included.
Gastrointestinal disorders Nausea	33.3% 1/3 • Number of events 1 • Up to ~26 months All treated participants are included.	0.00% 0/4 • Up to ~26 months All treated participants are included.
General disorders Malaise	33.3% 1/3 • Number of events 1 • Up to ~26 months All treated participants are included.	0.00% 0/4 • Up to ~26 months All treated participants are included.
General disorders Mucosal inflammation	0.00% 0/3 • Up to ~26 months All treated participants are included.	25.0% 1/4 • Number of events 1 • Up to ~26 months All treated participants are included.
General disorders Oedema peripheral	0.00% 0/3 • Up to ~26 months All treated participants are included.	50.0% 2/4 • Number of events 2 • Up to ~26 months All treated participants are included.
General disorders Pyrexia	0.00% 0/3 • Up to ~26 months All treated participants are included.	25.0% 1/4 • Number of events 2 • Up to ~26 months All treated participants are included.
General disorders Thirst	0.00% 0/3 • Up to ~26 months All treated participants are included.	25.0% 1/4 • Number of events 1 • Up to ~26 months All treated participants are included.
Infections and infestations Oral candidiasis	0.00% 0/3 • Up to ~26 months All treated participants are included.	25.0% 1/4 • Number of events 1 • Up to ~26 months All treated participants are included.
Infections and infestations Paronychia	0.00% 0/3 • Up to ~26 months All treated participants are included.	25.0% 1/4 • Number of events 1 • Up to ~26 months All treated participants are included.
Infections and infestations Pneumonia	33.3% 1/3 • Number of events 1 • Up to ~26 months All treated participants are included.	0.00% 0/4 • Up to ~26 months All treated participants are included.
Injury, poisoning and procedural complications Arthropod sting	0.00% 0/3 • Up to ~26 months All treated participants are included.	25.0% 1/4 • Number of events 1 • Up to ~26 months All treated participants are included.
Injury, poisoning and procedural complications Fall	0.00% 0/3 • Up to ~26 months All treated participants are included.	25.0% 1/4 • Number of events 1 • Up to ~26 months All treated participants are included.
Investigations Alanine aminotransferase increased	33.3% 1/3 • Number of events 1 • Up to ~26 months All treated participants are included.	0.00% 0/4 • Up to ~26 months All treated participants are included.
Investigations Aspartate aminotransferase increased	33.3% 1/3 • Number of events 1 • Up to ~26 months All treated participants are included.	0.00% 0/4 • Up to ~26 months All treated participants are included.
Investigations Blood creatine phosphokinase increased	0.00% 0/3 • Up to ~26 months All treated participants are included.	25.0% 1/4 • Number of events 1 • Up to ~26 months All treated participants are included.
Investigations Blood creatinine increased	0.00% 0/3 • Up to ~26 months All treated participants are included.	25.0% 1/4 • Number of events 1 • Up to ~26 months All treated participants are included.
Investigations Blood pressure decreased	33.3% 1/3 • Number of events 1 • Up to ~26 months All treated participants are included.	0.00% 0/4 • Up to ~26 months All treated participants are included.
Investigations Haemoglobin decreased	33.3% 1/3 • Number of events 1 • Up to ~26 months All treated participants are included.	0.00% 0/4 • Up to ~26 months All treated participants are included.
Investigations Lymphocyte count increased	33.3% 1/3 • Number of events 1 • Up to ~26 months All treated participants are included.	25.0% 1/4 • Number of events 1 • Up to ~26 months All treated participants are included.
Investigations Pancreatic enzymes increased	0.00% 0/3 • Up to ~26 months All treated participants are included.	25.0% 1/4 • Number of events 2 • Up to ~26 months All treated participants are included.
Investigations Platelet count decreased	66.7% 2/3 • Number of events 2 • Up to ~26 months All treated participants are included.	0.00% 0/4 • Up to ~26 months All treated participants are included.
Metabolism and nutrition disorders Decreased appetite	33.3% 1/3 • Number of events 1 • Up to ~26 months All treated participants are included.	0.00% 0/4 • Up to ~26 months All treated participants are included.
Musculoskeletal and connective tissue disorders Myalgia	0.00% 0/3 • Up to ~26 months All treated participants are included.	25.0% 1/4 • Number of events 1 • Up to ~26 months All treated participants are included.
Nervous system disorders Dysgeusia	0.00% 0/3 • Up to ~26 months All treated participants are included.	50.0% 2/4 • Number of events 2 • Up to ~26 months All treated participants are included.