A Phase 3 interventional study of Nemtabrutinib and Venetoclax in Leukemia, Lymphocytic, Chronic, B-Cell, Leukemia, Chronic Lymphocytic and Small-Cell Lymphoma, sponsored by Merck Sharp & Dohme LLC. Recruiting at 106 sites in 23 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-11-06.
Sponsored by Merck Sharp & Dohme LLC (part of Merck & Co., Inc) · Phase 3, Interventional, and Treatment
The purpose of this study is to assess the safety and tolerability and to confirm the dose of nemtabrutinib in combination with venetoclax in participants with R/R CLL/SLL. The primary study hypotheses are that the combination of nemtabrutinib plus venetoclax is superior to VR with respect to progression-free survival (PFS) per 2018 International Workshop on Chronic Lymphocytic Leukemia (iwCLL) criteria as assessed by blinded independent central review (BICR).
2,036 studies on the registry are indexed under Leukemia, Lymphocytic, Chronic, B-Cell; 237 are open to participants now.
This study's planned enrollment of 735 is above the median of 39 across 1,603 interventional studies indexed under Leukemia, Lymphocytic, Chronic, B-Cell.
Browse Leukemia, Lymphocytic, Chronic, B-Cell studies →Merck Sharp & Dohme LLC is the lead sponsor of 2,166 studies on the registry; 132 are open to participants now.
Of its 501 completed or terminated interventional studies of FDA-regulated products, 370 (74%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Relapsed: the illness came back after treatment had worked. Refractory: it did not respond to treatment, or stopped responding while still on it.
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
CYP3A is a group of enzymes, mainly CYP3A4, in the liver and gut that break down many medicines. Some medicines, supplements and foods (grapefruit, St John’s wort) slow them down or speed them up, which changes how much of a study drug stays in the body.
Studies list them so they can be avoided or switched; bring a list of everything you take, including supplements.
Vaccines made with a weakened form of the germ, such as measles–mumps–rubella (MMR), chickenpox and yellow fever. They can be risky when the immune system is weakened. Flu injections are not live; the nasal flu spray is.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Relapsed and refractory
Relapsed: the illness came back after treatment had worked. Refractory: it did not respond to treatment, or stopped responding while still on it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECOG performance status
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Life expectancy
The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis B tests
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis C tests
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Excipients
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
CYP3A (CYP3A4) inhibitors and inducers
CYP3A is a group of enzymes, mainly CYP3A4, in the liver and gut that break down many medicines. Some medicines, supplements and foods (grapefruit, St John’s wort) slow them down or speed them up, which changes how much of a study drug stays in the body.
Studies list them so they can be avoided or switched; bring a list of everything you take, including supplements.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Live vaccines
Vaccines made with a weakened form of the germ, such as measles–mumps–rubella (MMR), chickenpox and yellow fever. They can be risky when the immune system is weakened. Flu injections are not live; the nasal flu spray is.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants will receive nemtrabrutinib oral tablets at specified doses daily starting at Cycle 1 Day 1 (C1D1) and venetoclax oral tablets at doses of 20 mg up to 400 mg daily starting at Cycle 2 Day 1 (C2D1) up to 2 years post C2D1 or until progressive disease (PD) or discontinuation. A cycle = 4 weeks.
Drug: Nemtabrutinib · Drug: Venetoclax
Participants will receive venetoclax oral tablets at doses from 20 mg up to 400 mg daily starting at C1D1 on 4-week cycles up to 2 years and rituximab or biosimilar at 375 mg/m\^2 up to 500 mg/m2 intravenous infusion once per 28-day cycle starting at C2D1, for 6 total cycles. Treatment will continue until progressive disease (PD) or discontinuation.
Drug: Venetoclax · Biological: Rituximab
5, 20, and 45 tablets
Also known as: ARQ 531, MK-1026
10, 50, and 100 mg tablets
Also known as: ABT-199, GDC-0199
100 mg/10 mL, 500 mg/50 mL (10 mg/mL) IV Infusion
Part 1: Number of Participants Experiencing Dose-Limiting Toxicities (DLTs)
DLT evaluation period is defined as 8 weeks after the first dose of the combination treatment of nemtabrutinib plus venetoclax Cycle 2 Day 1 in Part 1 + 4 weeks follow up. Each cycle is 4 weeks. DLTs are: Grade ≥3 nonhematologic toxicity (except Grade 3 nausea, vomiting, diarrhea, rash, fatigue, and uncontrolled hypertension which will not be considered a DLT unless lasting ≥72 hours despite optimal supportive care); Grade 4 hematologic toxicity lasting \>7 days (except Grade 3 lymphocytosis, Grade 4 platelet count decreased of any duration, or Grade 3 platelet count decreased if associated with bleeding); any Grade 3 or Grade 4 nonhematologic laboratory abnormality if values result in drug-induced liver injury, or medical intervention is required, or the abnormality leads to hospitalization, or the abnormality persists for \>1 week (with exceptions); missing \>25% of nemtabrutinib or venetoclax doses as a result of drug-related adverse events during the first 2 cycles; Grade 5 toxicity.
Time frame: Up to approximately 12 Weeks
Part 1: Number of Participants Experiencing Adverse Events (AEs)
An AE is any untoward medical occurrence in a participant, temporally associated with the use of study treatment, whether or not considered related to the study treatment. The number of participants experiencing AEs will be reported for Part 1.
Time frame: Up to approximately 28 months
Part 1: Number of Participants Discontinuing Study Treatment Due to AEs
An AE is any untoward medical occurrence in a participant, temporally associated with the use of study treatment, whether or not considered related to the study treatment. The number of participants discontinuing study treatment due to AEs will be reported for Part 1.
Time frame: Up to approximately 25 months
Part 2: PFS per the 2018 International Workshop on Chronic Lymphocytic Leukemia (iwCLL) Criteria as Assessed by Blinded Independent Central Review (BICR)
PFS is defined as the time from randomization to the first documented disease progression per iwCLL criteria 2018 as accessed by BICR, or death due to any cause, whichever occurs first. PFS will be presented.
Time frame: Up to approximately 71 months
Part 2: Undetectable Minimal Residual Disease (MRD) Rate in Bone Marrow as Assessed by Central Laboratory
Undetectable MRD, defined as \<1 leukemic cell per 10,000 cells (MRD \<10-4) in bone marrow. The MRD rate will be presented.
Time frame: Up to approximately 46 months
Part 2: Overall Survival (OS)
OS, defined as the time from randomization to death due to any cause. OS will be presented.
Time frame: Up to approximately 108 months
Part 2: Objective Response Rate (ORR) per iwCLL Criteria 2018 as Assessed by BICR
OR, defined as complete response/remission (CR), complete response with incomplete count recovery (CRi), nodular partial remission (nPR), or partial remission (PR). 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). CRi is defined as meeting CR criteria but with hypocellular bone marrow. nPR is defined as having features of CR but with lymphoid nodules in the marrow. 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. ORR will be presented.
Time frame: Up to approximately 71 months
Part 2: Duration of Response (DOR) per iwCLL Criteria 2018 as Assessed by BICR
DOR, defined as the time from the first documented evidence of CR, CRi, nPR, or PR that led to response until disease progression 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). CRi is defined as meeting CR criteria but with hypocellular bone marrow. nPR is defined as having features of CR but with lymphoid nodules in the marrow. 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. DOR will be presented.
Time frame: Up to approximately 108 months
Part 2: Number of Participants Experiencing AEs
An AE is any untoward medical occurrence in a participant, temporally associated with the use of study treatment, whether or not considered related to the study treatment. The number of participants experiencing AEs will be reported for Part 2.
Time frame: Up to approximately 28 months
Part 2: Number of Participants Discontinuing Study Treatment Due to AEs
An AE is any untoward medical occurrence in a participant, temporally associated with the use of study treatment, whether or not considered related to the study treatment. The number of participants discontinuing study treatment due to AEs will be reported for Part 2.
Time frame: Up to approximately 25 months
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Plan to share: Yes — https://trialstransparency.msdclinicaltrials.com/pdf/ProcedureAccessClinicalTrialData.pdf
Data sharing details ↗ · externaldatasharing-msd.com
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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Studies of the drug tested here: ARQ531
Leukemia, Lymphocytic, Chronic, B-Cell →