A Phase 1/2 interventional study of Nemtabrutinib in Lymphoma, B-Cell, Small Lymphocytic Lymphoma and Chronic Lymphocytic Leukemia, sponsored by ArQule, Inc., a subsidiary of Merck Sharp & Dohme LLC, a subsidiary of Merck & Co., Inc. (Rahway, NJ USA). Active, not recruiting at 10 sites in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-06-12.
Sponsored by ArQule, Inc., a subsidiary of Merck Sharp & Dohme LLC, a subsidiary of Merck & Co., Inc. (Rahway, NJ USA) · Phase 1/2, Interventional, and Treatment
This study aims to evaluate the safety, tolerability, pharmacodynamic, and pharmacokinetic (PK) of nemtabrutinib (formerly ARQ 531) tablets in selected participants with relapsed or refractory hematologic malignancies. No formal hypothesis testing will be performed for this study.
This study includes 2 parts: Phase 1 (dose escalation) and Phase 2 (dose expansion). In Phase 1, participants will enroll using 3+3 dose escalation design. The starting dose of nemtabrutinib in oral tablet form was 5mg/day continuously. Dose escalation will continue until the maximum tolerated dose (MTD) and/or recommended Phase 2 dose (RP2D) and dosing schedule is reached based on protocol-defined dose limiting toxicity (DLT). After the determination of the RP2D, 9 expansion cohorts will be initiated to evaluate the safety, tolerability, and efficacy of nemtabrutinib at RP2D in participants with specifically defined disease.
1,411 studies on the registry are indexed under Lymphoma, B-Cell; 329 are open to participants now.
This study's planned enrollment of 190 is above the median of 36 across 1,218 interventional studies indexed under Lymphoma, B-Cell.
Browse Lymphoma, B-Cell studies →ArQule, Inc., a subsidiary of Merck Sharp & Dohme LLC, a subsidiary of Merck & Co., Inc. (Rahway, NJ USA) is the lead sponsor of 32 studies on the registry; none are open to participants now.
Counted across the registry records on this site, refreshed daily.
Each prospective participant must meet ALL of the following inclusion criteria in order to be eligible for this study:
For the expansion cohorts, the following criteria must be met:
Disease status requirement:
Exclusion Criteria
Potential participants who meet ANY of the following exclusion criteria are not eligible for enrollment into this study:
Participants currently being treated with the following drugs:
Phase I: Dose Escalation and determination of RP2D, multiple dose levels of nemtabrutinib to be evaluated (Up to approximately 22 months).
Drug: Nemtabrutinib
Relapsed/Refractory chronic lymphocytic leukemia/small lymphocytic lymphoma (R/R CLL/SLL) participants with at least 2 prior systemic therapies and previously treated with a covalent Bruton's tyrosine kinase inhibitor (BTKi) who must have a documented BTK mutation on C481 residue receive up to 65 mg of nemtabrutinib per day orally in each cycle (Cycle length = 28 days) until progressive disease (PD), unacceptable adverse events (AEs), or discontinuation at investigator's discretion (up to approximately 64 months).
Drug: Nemtabrutinib
R/R CLL/SLL participants who have failed or were intolerant to a BTKi with documentation of the absence of BTK mutation on C481 residue receive up to 65 mg of nemtabrutinib per day orally in each cycle (Cycle length = 28 days) until PD, unacceptable AEs, or discontinuation at investigator's discretion (up to approximately 64 months).
Drug: Nemtabrutinib
Richter's transformation (RT) participants who have failed at least one prior therapy receive up to 65 mg of nemtabrutinib per day orally in each cycle (Cycle length = 28 days) until PD, unacceptable AEs, or discontinuation at investigator's discretion (up to approximately 64 months).
Drug: Nemtabrutinib
Follicular Lymphoma (FL) participants who have failed at least 2 prior systemic therapies and are histology grade 1, 2, or 3A receive up to 65 mg of nemtabrutinib per day orally in each cycle (Cycle length = 28 days) until PD, unacceptable AEs, or discontinuation at investigator's discretion (up to approximately 64 months).
Drug: Nemtabrutinib
Mantle Cell Lymphoma (MCL) participants who have failed at least 2 prior systemic therapies receive up to 65 mg of nemtabrutinib per day orally in each cycle (Cycle length = 28 days) until PD, unacceptable AEs, or discontinuation at investigator's discretion (up to approximately 64 months).
Drug: Nemtabrutinib
Marginal Zone Lymphoma (MZL) participants who have failed at least 2 prior systemic therapies receive up to 65 mg of nemtabrutinib per day orally in each cycle (Cycle length = 28 days) until PD, unacceptable AEs, or discontinuation at investigator's discretion (up to approximately 64 months).
Drug: Nemtabrutinib
High-grade B-cell lymphoma (BCL) participants who have failed at least 2 prior systemic therapies and have known MYC and BCL2 and/or BCL6 translocations confirmed by flourescence in situ hybridization (FISH) or overexpression by immunohistochemistry (IHC) receive up to 65 mg of nemtabrutinib per day orally in each cycle (Cycle length = 28 days) until PD, unacceptable AEs, or discontinuation at investigator's discretion (up to approximately 64 months).
Drug: Nemtabrutinib
Waldenström macroglobulinemia (WM) participants who have failed at least 2 prior systemic therapies receive up to 65 mg of nemtabrutinib per day orally in each cycle (Cycle length = 28 days) until PD, unacceptable AEs, or discontinuation at investigator's discretion (up to approximately 64 months).
Drug: Nemtabrutinib
B-cell Non-Hodgkin's lymphoma (NHL), CLL/SLL and WM participants receive up to 65 mg of nemtabrutinib fasted (1 hour prior to or 2 hours after meal) and non-fasted per day orally in each cycle (Cycle length = 28 days) until PD, unacceptable AEs, or discontinuation at investigator's discretion (up to approximately 64 months).
Drug: Nemtabrutinib
Nemtabrutinib will be orally administered once per day under fasted conditions (1 hour prior to or 2 hours after a meal) and is available in tablets in strengths of 5 mg or 20 mg. For Expansion Food Effect Cohort I, nemtabrutinib will be orally administered once per day under fasted and non-fasted condition.
Also known as: ARQ 531, MK-1026
Phase 1: Number of Participants Experiencing Dose Limiting Toxicity (DLT)
DLT is defined by the occurrence of any of the following treatment emergent adverse event (TEAE) unless unequivocally due to the underlying malignancy or an extraneous cause within the first 28 days of study treatment (for dose escalation only) and graded according to National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE) version 4.03. Any Grade 5 TEAE, any Grade 3 nonhematological TEAE except alopecia, nausea, vomiting, diarrhea, and transient Grade 3 laboratory abnormalities which recover within 1 week without intervention, any Grade 3 hematological TEAE that does not recover to Grade 1 or baseline within 7 days with the exception of Grade 3 lymphocytosis, which is considered to be an expected outcome of BTK inhibition, any Grade 4 nonhematological and hematological TEAE, or any other toxicity that in the view of the investigator represents a clinically significant hazard to the participant.
Time frame: Cycle 1 (up to 28 days)
Phase 1: Number of Participants Who Experienced an Adverse Event (AE)
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. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of a study intervention. The number of participants who experienced an AE will be reported.
Time frame: Up to approximately 86 months
Phase 1: Number of Participants Who Discontinued Study Treatment Due to an AE
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. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of a study intervention. The number of participants who discontinued study treatment due to an AE will be reported.
Time frame: Up to approximately 86 months
Phase 2: Expansion Cohorts A, B & C: Objective Response Rate (ORR) per International Workshop on Chronic Lymphocytic Leukemia (iwCLL) Criteria as Assessed by the Investigator
ORR is defined as the percentage of participants achieving a best overall response of complete response (CR), partial response (PR) or partial response with lymphocytosis (PRL). iwCLL criteria as assessed by the investigator. CR is defined as meeting the following criteria: no lymph nodes \>1.5 cm, spleen size \<13 cm, liver normal; no constitutional symptoms, normal lymphocyte count, platelets ≥100 x 10\^9/L; hemoglobin ≥11 g/dL; and normocellular marrow (no CLL cells or B lymphoid nodules). PR is defined as ≥50% decrease in ≥2 of the following: lymph nodes, liver and/or spleen size, lymphocytes PLUS ≥1 of the following met: platelets ≥100 x 10\^9/L or ≥50% increase from screening, hemoglobin \>11 g/dL or ≥50% increase from screening, CLL cells or B lymphoid nodules in marrow.
Time frame: Up to approximately 64 months
Phase 2: Expansion Cohorts A, B, C: ORR per Lugano Classification as Assessed by the Investigator
ORR is defined as percentage of participants achieving best overall response of CR/PR per Lugano classification as assessed by investigator. CR defined as EITHER CR by imaging (computed tomography \[CT\]): all lymph nodes normal (none ≥15 mm) \& normal liver, spleen OR complete metabolic response (CMR): score of 1, 2 or3 on 5-point scale assessing fluorodeoxyglucose (FDG) metabolic activity in lymphomatous lesions (range: 1=no uptake above background to 5=uptake markedly higher than liver) AND bone marrow (BM) normal by morphology. PR defined as EITHER PR by imaging (CT) with ≥50% decrease in sum of product of diameters \[SPD\] of target lesions, no worsening of nontarget lesions, no new lesions and ≥50% spleen abnormal portion OR Partial Metabolic Response (PMR) with score of 4/5 on FDG 5-point scale (with no new lesions) \& decreased overall uptake AND residual BM abnormalities; OR CR by imaging with residual BM abnormalities; OR PR by imaging without residual BM abnormalities.
Time frame: Up to approximately 64 months
Phase 2: Number of Participants Who Experienced an AE
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. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of a study intervention. The number of participants who experienced an AE will be reported.
Time frame: Up to approximately 64 months
Phase 2: Number of Participants Who Discontinued Study Treatment Due to an AE
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. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of a study intervention. The number of participants who discontinued study treatment due to an AE will be reported.
Time frame: Up to approximately 64 months
Time to Maximum Concentration (Tmax) of Nemtabrutinib
Blood samples will be collected at prespecified time points to determine Tmax of nemtabrutinib.
Time frame: Cycles 1-92: Days 1, 2: Predose and up to 16 hours postdose (each cycle length = 28 days, up to approximately 86 months)
Maximum Concentration (Cmax) of Nemtabrutinib
Blood samples will be collected at prespecified time points to determine Cmax of nemtabrutinib.
Time frame: Cycles 1-92: Days 1, 2: Predose and up to 16 hours postdose (each cycle length = 28 days, up to approximately 86 months)
Area Under the Concentration-Time Curve From Time Zero to 24 Hours (AUC 0-24hrs)of Nemtabrutinib
Blood samples will be collected at prespecified time points to determine AUC 0-24hrs of nemtabrutinib.
Time frame: Cycles 1-92: Days 1, 2: Predose and up to 24 hours postdose (each cycle length = 28 days, up to approximately 86 months)
Terminal Elimination Half-Life (t1/2) of Nemtabrutinib
t1/2 is the time it takes for the concentration of nemtabrutinib in the body to decrease by half during the elimination phase.
Time frame: Cycles 1-92: Days 1, 2: Predose and up to 16 hours postdose (each cycle length = 28 days, up to approximately 86 months)
Phase 2: Expansion Cohorts D-H: ORR per iwCLL Criteria as Assessed by the Investigator
ORR is defined as the percentage of participants achieving a best overall response of complete response (CR), partial response (PR) or partial response with lymphocytosis (PRL). iwCLL criteria as assessed by the investigator. CR is defined as meeting the following criteria: no lymph nodes \>1.5 cm, spleen size \<13 cm, liver normal; no constitutional symptoms, normal lymphocyte count, platelets ≥100 x 10\^9/L; hemoglobin ≥11 g/dL; and normocellular marrow (no CLL cells or B lymphoid nodules). PR is defined as ≥50% decrease in ≥2 of the following: lymph nodes, liver and/or spleen size, lymphocytes PLUS ≥1 of the following met: platelets ≥100 x 10\^9/L or ≥50% increase from screening, hemoglobin \>11 g/dL or ≥50% increase from screening, CLL cells or B lymphoid nodules in marrow.
Time frame: Up to approximately 64 months
Phase 2: Expansion Cohorts D-H: ORR per Lugano classification as Assessed by the Investigator
ORR is defined as percentage of participants achieving best overall response of CR/PR per Lugano classification as assessed by investigator. CR defined as EITHER CR by imaging (computed tomography \[CT\]): all lymph nodes normal (none ≥15 mm) \& normal liver, spleen OR complete metabolic response (CMR): score of 1, 2 or3 on 5-point scale assessing fluorodeoxyglucose (FDG) metabolic activity in lymphomatous lesions (range: 1=no uptake above background to 5=uptake markedly higher than liver) AND bone marrow (BM) normal by morphology. PR defined as EITHER PR by imaging (CT) with ≥50% decrease in sum of product of diameters \[SPD\] of target lesions, no worsening of nontarget lesions, no new lesions and ≥50% spleen abnormal portion OR Partial Metabolic Response (PMR) with score of 4/5 on FDG 5-point scale (with no new lesions) \& decreased overall uptake AND residual BM abnormalities; OR CR by imaging with residual BM abnormalities; OR PR by imaging without residual BM abnormalities.
Time frame: Up to approximately 64 months
Phase 2: Expansion Cohorts A, B, H: Duration of Response (DOR) per iwCLL Criteria as Assessed by the Investigator
DOR is defined as the time from the first documented evidence of CR or PR (or PRL for CLL/SLL participants) until progressive disease or death due to any cause, whichever occurs first. CR is defined as meeting the following criteria: no lymph nodes \>1.5 cm, spleen size \<13 cm, liver normal; no constitutional symptoms, normal lymphocyte count, platelets ≥100 x 10\^9/L; hemoglobin ≥11 g/dL; and normocellular marrow (no CLL cells or B lymphoid nodules). PR is defined as ≥50% decrease in ≥2 of the following: lymph nodes, liver and/or spleen size, lymphocytes PLUS ≥1 of the following met: platelets ≥100 x 10\^9/L or ≥50% increase from screening, hemoglobin \>11 g/dL or ≥50% increase from screening, CLL cells or B lymphoid nodules in marrow.
Time frame: Up to approximately 64 months
Phase 2: Expansion Cohorts C-G: DOR per Laguna Classification As Assessed by Investiigator
DOR is defined as time from first documented evidence of CR/PR (or PRL for CLL/SLL participants) until progressive disease or death due to any cause, whichever occurs first. CR defined as EITHER CR by imaging (computed tomography \[CT\]): all lymph nodes normal (none ≥15 mm) \& normal liver, spleen OR complete metabolic response (CMR): score of 1, 2 or3 on 5-point scale assessing FDG metabolic activity in lymphomatous lesions (range: 1=no uptake above background to 5=uptake markedly higher than liver) AND BM normal by morphology. PR defined as EITHER PR by imaging (CT) with ≥50% decrease in SPD of target lesions, no worsening of nontarget lesions, no new lesions and ≥50% spleen abnormal portion OR PMR with score of 4/5 on FDG 5-point scale (with no new lesions) \& decreased overall uptake AND residual BM abnormalities; OR CR by imaging with residual BM abnormalities; OR PR by imaging without residual BM abnormalities.
Time frame: Up to approximately 64 months
Plan to share: Yes — https://trialstransparency.msdclinicaltrials.com/pdf/ProcedureAccessClinicalTrialData.pdf
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ArQule, Inc., a subsidiary of Merck Sharp & Dohme LLC, a subsidiary of Merck & Co., Inc. (Rahway, NJ USA)