A Phase 2 interventional study of Nemtabrutinib in Hematologic Malignancies, Waldenstroms Macroglobulinaemia and Non-Hodgkins Lymphoma, sponsored by Merck Sharp & Dohme LLC. Recruiting at 121 sites in 22 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-10-27.
Sponsored by Merck Sharp & Dohme LLC (part of Merck & Co., Inc) · Phase 2, Interventional, and Treatment
The purpose of this study is to evaluate the safety and efficacy of nemtabrutinib (formerly ARQ 531) in participants with hematologic malignancies of chronic lymphocytic leukemia (CLL)/ small lymphocytic lymphoma (SLL), Richter's transformation, marginal zone lymphoma (MZL), mantle cell lymphoma (MCL), follicular lymphoma (FL), and Waldenström's macroglobulinemia (WM).
This study will be performed in 2 parts: Dose Escalation and Confirmation (Part 1) and Cohort Expansion (Part 2). Following determination of the recommended phase 2 dose (RP2D) in Part 1, the study plans to proceed with Part 2 using 8 disease-specific expansion cohorts (Cohorts A to H).
1,444 studies on the registry are indexed under Hematologic Neoplasms; 420 are open to participants now.
This study's planned enrollment of 490 is above the median of 46 across 1,044 interventional studies indexed under Hematologic Neoplasms.
Browse Hematologic Neoplasms 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.
Part 1 and Part 2 (Cohorts A to C and J)
Has a confirmed diagnosis of Chronic lymphocytic leukemia/ Small lymphocytic lymphoma (CLL/SLL) with
Part 2 (Cohorts D to G)
- Has a confirmed diagnosis of and meets the following prior therapy requirements:
Part 2 (Cohort H): confirmed diagnosis of Waldenström's macroglobulinemia (WM); participants who are relapsed or refractory to standard therapies for WM including chemoimmunotherapy and a covalent irreversible BTKi
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.
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.
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.
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.
The number of CD4 cells, a type of white blood cell, in a given amount of blood. It is used to follow how well the immune system is doing in HIV.
A line of therapy is one course of treatment, which may combine several drugs. First-line is the first course given; second-line follows when that stops working or is not tolerated.
“Two prior lines” means two courses that count separately under the study’s rules — not simply two drugs. Ask the study team if you are unsure how yours are counted.
Relapsed: the illness came back after treatment had worked. Refractory: it did not respond to treatment, or stopped responding while still on it.
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).
Your pathology report is the document that shows this.
The amount of disease can be tracked with a defined measurement, so the study can see whether it shrinks or grows. It might be a tumour measured on a scan or, in some blood cancers such as myeloma, a marker measured in blood or urine.
The criteria or the study team say which measurement counts — having no tumour visible on a scan does not by itself rule you out.
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.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
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.
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.
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.
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.
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.
CD4 count
The number of CD4 cells, a type of white blood cell, in a given amount of blood. It is used to follow how well the immune system is doing in HIV.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Line of therapy
A line of therapy is one course of treatment, which may combine several drugs. First-line is the first course given; second-line follows when that stops working or is not tolerated.
“Two prior lines” means two courses that count separately under the study’s rules — not simply two drugs. Ask the study team if you are unsure how yours are counted.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Biopsy and archival tissue
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Histologically or cytologically confirmed
The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).
Your pathology report is the document that shows this.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Measurable disease
The amount of disease can be tracked with a defined measurement, so the study can see whether it shrinks or grows. It might be a tumour measured on a scan or, in some blood cancers such as myeloma, a marker measured in blood or urine.
The criteria or the study team say which measurement counts — having no tumour visible on a scan does not by itself rule you out.
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.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
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.
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.
Participants receive nemtabrutinib orally once daily (QD) until progressive disease (PD) or discontinuation.
Drug: Nemtabrutinib
Nemtabrutinib tablets administered orally QD.
Also known as: ARQ 531, MK-1026
Part 1: Number of participants experiencing dose-limiting toxicities (DLTs)
DLTs will be defined as toxicities observed during the first 2 cycles (8 weeks) of Part 1 and include: 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 doses as a result of drug-related adverse events (AEs) during the first 2 cycles (8 weeks); Grade 5 toxicity.
Time frame: Up to ~56 days (Cycles 1-2, cycle = 28 days)
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 ~71 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 an AE will be reported for Part 1.
Time frame: Up to ~42 months
Part 2: Objective Response Rate (ORR) per International Workshop on Chronic Lymphocytic Leukemia (iwCLL) criteria 2018 as assessed by independent central review (ICR)
ORR per iwCLL 2018 criteria is defined as the percentage of participants achieving a complete response (CR), complete response with incomplete bone marrow recovery (CRi), nodular partial response (nPR), or partial response (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.
Time frame: Up to ~61 months
Part 2: ORR per Lugano criteria 2014 as assessed by ICR
ORR per Lugano criteria 2014 is defined as the percentage of participants achieving a CR or PR. CR defined as EITHER CR by imaging (computed tomography \[CT\]): all lymph nodes normal (none ≥15 mm) and normal liver and spleen OR complete metabolic response (CMR): score of 1, 2 or 3 on the 5-point scale assessing fluorodeoxyglucose (FDG) metabolic activity in lymphomatous lesions (ranging from 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 the sum of the 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 or 5 on the FDG 5-point scale (with no new lesions) and 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 ~61 months
Part 2: ORR per International Workshop on Waldenström's Macroglobulinemia (IWWM) criteria 2014 as assessed by ICR
ORR per IWWM criteria 2014 is defined as the percentage of participants achieving a CR, very good partial response (VGPR), or PR. CR is defined as all lymph nodes are normal in size (none ≥15 mm), liver and spleen normal in size, serum immunoglobulin M (IgM) values in the normal range, disappearance of monoclonal protein by immunofixation (confirmation needed with a second immunofixation at any subsequent timepoint), and no histological evidence of BM involvement. VGPR is defined as ≥50% decrease from baseline in SPD of lymph nodes (if abnormal at baseline), ≥50% decrease from baseline in the abnormal portion of the spleen (if previously abnormal), and ≥90% decrease from baseline in serum IgM, or serum IgM values in normal range. PR is defined as ≥50% decrease from baseline in SPD of lymph nodes (if abnormal at baseline), ≥50% decrease from baseline in serum IgM, and ≥50% decrease from baseline in the abnormal portion of the spleen (if previously abnormal).
Time frame: Up to ~71 months
Part 1: Area Under the Curve (AUC) of Nemtabrutinib
Blood samples will be obtained at designated time points during Part 1 for the assessment of nemtabrutinib AUC (Day 1 of Cycles 1 and 2: Pre-dose, 2, 4, 6, 8, and 24 hours post-dose; Day 1 of Cycle 3: pre-dose and 2, 4, and 6 hours post-dose \[up to \~57 days\]). Each cycle is 28 days.
Time frame: At designated time points (up to ~57 days)
Part 1: Minimum Concentration (Cmin) of Nemtabrutinib
Blood samples will be obtained at designated time points during Part 1 for the assessment of nemtabrutinib Cmin (Day 1 of Cycles 1 and 2: Pre-dose, 2, 4, 6, 8, and 24 hours post-dose; Day 1 of Cycle 3: pre-dose and 2, 4, and 6 hours post-dose \[up to \~57 days\]). Each cycle is 28 days.
Time frame: At designated time points (up to ~57 days)
Part 1: Maximum Concentration (Cmax) of Nemtabrutinib
Blood samples will be obtained at designated time points during Part 1 for the assessment of nemtabrutinib Cmax (Day 1 of Cycles 1 and 2: Pre-dose, 2, 4, 6, 8, and 24 hours post-dose; Day 1 of Cycle 3: pre-dose and 2, 4, and 6 hours post-dose \[up to \~57 days\]). Each cycle is 28 days.
Time frame: At designated time points (up to ~57 days)
Part 1: ORR per iwCLL criteria 2018 as assessed by ICR
ORR per iwCLL 2018 criteria is defined as the percentage of participants achieving a CR, CRi, nPR, or 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.
Time frame: Up to ~71 months
Part 1: Duration of Response (DOR) per iwCLL criteria 2018 as assessed by ICR
For participants with CR, CRi, nPR, or PR per iwCLL 2018 criteria, DOR is defined as the time from the first documented evidence of objective response until PD 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.
Time frame: Up to ~71 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 ~61 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 an AE will be reported for Part 2.
Time frame: Up to ~42 months
Part 2: AUC of Nemtabrutinib
Blood samples will be obtained at designated time points during Part 2 for the assessment of nemtabrutinib AUC (Day 1 of Cycles 1, 2, and 3: Pre-dose, 2, 4, 6, hours post-dose \[up to \~57 days\]). Each cycle is 28 days.
Time frame: At designated time points (up to ~57 days)
Part 2: Cmin of Nemtabrutinib
Blood samples will be obtained at designated time points during Part 2 for the assessment of nemtabrutinib Cmin (Day 1 of Cycles 1, 2, and 3: Pre-dose, 2, 4, 6, hours post-dose \[up to \~57 days\]). Each cycle is 28 days.
Time frame: At designated time points (up to ~57 days)
Part 2: Cmax of Nemtabrutinib
Blood samples will be obtained at designated time points during Part 2 for the assessment of nemtabrutinib Cmax (Day 1 of Cycles 1, 2, and 3: Pre-dose, 2, 4, 6, hours post-dose \[up to \~57 days\]). Each cycle is 28 days.
Time frame: At designated time points (up to ~57 days)
Part 2: DOR per iwCLL criteria 2018 as assessed by ICR
For participants with CR, CRi, nPR, or PR per iwCLL 2018 criteria, DOR is defined as the time from the first documented evidence of objective 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.
Time frame: Up to ~61 months
Part 2: DOR per Lugano criteria 2014 as assessed by ICR
For participants with CR or PR per Lugano criteria 2014, DOR is defined as the time from the first documented evidence of objective response until PD or death due to any cause, whichever occurs first. CR defined as EITHER CR by imaging (CT): all lymph nodes normal (none ≥15 mm) and normal liver and spleen OR CMR: score of 1, 2 or 3 on the 5-point scale assessing FDG metabolic activity in lymphomatous lesions (ranging from 1=no uptake above background to 5=uptake markedly higher than liver and/or new lesions) AND BM normal by morphology. PR defined as EITHER PR by imaging (CT) with ≥50% decrease in the SPD of target lesions, no worsening of nontarget lesions, no new lesions and ≥50% spleen abnormal portion OR PMR with score of 4 or 5 on the FDG 5-point scale (with no new lesions) and 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 ~61 months
Part 2: DOR per IWWM criteria 2014 as assessed by ICR
For participants with CR, VGPR, or PR per IWWM criteria 2014, DOR defined as the time from first documented evidence of objective response until PD or death due to any cause, whichever occurs first. CR defined as all lymph nodes normal in size (none ≥15 mm), liver and spleen normal in size, serum IgM values in normal range, disappearance of monoclonal protein by immunofixation (confirmation needed with second immunofixation at any subsequent timepoint), and no histological evidence of BM involvement. VGPR defined as ≥50% decrease from baseline in SPD of lymph nodes (if abnormal at baseline), ≥50% decrease from baseline in abnormal portion of the spleen (if previously abnormal), and ≥90% decrease from baseline in serum IgM, or serum IgM values in normal range. PR is defined as ≥50% decrease from baseline in SPD of lymph nodes (if abnormal at baseline), ≥50% decrease from baseline in serum IgM, and ≥50% decrease from baseline in abnormal portion of the spleen (if previously abnormal).
Time frame: Up to ~61 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 ↗
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
Contact study teamGet an email when the registry record changes — status, dates, results — or when someone posts here.
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Studies of the drug tested here: ARQ531