A Phase 2/3 interventional study of MK-1045 and Blinatumomab in B-cell Acute Lymphoblastic Leukemia, sponsored by Merck Sharp & Dohme LLC. Recruiting at 30 sites in 10 countries. Open to participants aged 12 Years and older. Per ClinicalTrials.gov, last updated 2026-11-10.
Sponsored by Merck Sharp & Dohme LLC (part of Merck & Co., Inc) · Phase 2/3, Interventional, and Treatment
Researchers are looking for new ways to treat people with relapsed or refractory B-cell acute lymphoblastic leukemia (R/R B-ALL) that is CD19 positive using a medicine called MK-1045. MK-1045 is an immunotherapy, which is a treatment that helps the immune system fight cancer. This trial will compare MK-1045 to a standard immunotherapy called blinatumomab. The goals of this trial are to learn if more people who receive MK-1045 have no cancer cells in their bone marrow compared to people who receive blinatumomab and if people who receive MK-1045 live longer compared to people who receive blinatumomab.
This study has 2 parts: Part 1 is a dose optimization phase of MK-1045. Part 2 is a randomized phase comparing the efficacy and safety of MK-1045 versus blinatumomab and will use the recommended dose of MK-1045 determined in Part 1
976 studies on the registry are indexed under Burkitt Lymphoma; 159 are open to participants now.
This study's planned enrollment of 340 is above the median of 36 across 765 interventional studies indexed under Burkitt Lymphoma.
Browse Burkitt Lymphoma 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.
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.
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.
After a transplant from a donor, the donor’s immune cells attack the recipient’s body, often the skin, gut or liver.
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.
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
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.
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
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.
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.
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.
GVHD (graft-versus-host disease)
After a transplant from a donor, the donor’s immune cells attack the recipient’s body, often the skin, gut or liver.
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.
Immunosuppression
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
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.
Autoimmune disease
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants will receive a lower MK-1045 dose once weekly for up to 13 cycles (two 28-day and eleven 42-day cycles). Participants will have the option to change treatment at the end of Part 1.
Biological: MK-1045 · Drug: Acetaminophen · Drug: Diphenhydramine · Drug: Dexamethasone · Drug: Tocilizumab · Drug: Siltuximab · Drug: Avtozma · Drug: Tyenne
Participants will receive a larger MK-1045 dose once weekly for up to 13 cycles (two 28-day and eleven 42-day cycles). Participants will have the option to change treatment at the end of Part 1.
Biological: MK-1045 · Drug: Acetaminophen · Drug: Diphenhydramine · Drug: Dexamethasone · Drug: Tocilizumab · Drug: Siltuximab · Drug: Avtozma · Drug: Tyenne
Participants will receive blinatumomab on days 1, 8, 15, and 22 of each 42-day cycle
Biological: Blinatumomab · Drug: Dexamethasone · Drug: Tocilizumab · Drug: Siltuximab · Drug: Avtozma · Drug: Tyenne
Intravenous administration
Intravenous administration
Oral administration as a premedication
Intravenous administration as a premedication
Intravenous administration as a premedication
Intravenous administration as a rescue medication
Intravenous administration as a rescue medication
Intravenous administration as a rescue medication
Intravenous administration as a rescue medication
Percentage of Participants with Complete Remission (CR) in Study Part 1 and Part 2
CR is defined as: * No circulating lymphoblasts * Extramedullary disease negative * Trilineage hematopoiesis (TLH) and \<5% leukemic blasts * Absolute neutrophil count (ANC) ≥1000/μL * Platelets ≥100,000/μL * No platelet transfusions in the last 7 days * No administration of short-acting granulocyte colony-stimulating factor (G-CSF) and long-acting G-CSF in the last 3 and 14 days, respectively
Time frame: 3 treatment cycles (up to approximately 126 days; each cycle is up to 42 days; cycle lengths vary between cycle and arm)
Percentage of Participants Who Experience an Adverse Event (AE) in Study Part 1
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. The percentage of participants with at least 1 AE will be presented.
Time frame: 3 treatment cycles (up to approximately 126 days; each cycle is up to 42 days; cycle lengths vary between cycle and arm)
Percentage of Participants Who Discontinue Study Intervention Due to an AE in Study Part 1
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. The percentage of participants who discontinue study intervention due to an AE will be presented.
Time frame: 3 treatment cycles (up to approximately 126 days; each cycle is up to 42 days; cycle lengths vary between cycle and arm)
Overall Survival (OS) in Study Part 2
OS is the time from randomization to death due to any cause.
Time frame: Up to approximately 7 years
Overall survival (OS) in Study Part 1
OS is the time from randomization to death due to any cause.
Time frame: Up to approximately 7 years
Percentage of Participants that achieve Minimal Residual Disease (MRD) in Study Part 1 and Part 2
MRD is defined as no detectable leukemia cells below a threshold of at least 10\^-4.
Time frame: 3 treatment cycles (up to approximately 126 days; each cycle is up to 42 days; cycle lengths vary between cycle and arm)
Percentage of Participants that achieve CR/CR with partial hematologic recovery (CRh)/CR with incomplete count recovery (CRi) in Study Part 1 and Part 2
For participants who demonstrate CR or CRh or CRi, duration of remission is defined as the time from the first documented evidence of CR or CRh or CRi (whichever is earlier) until disease progression, relapse, or death due to any cause, whichever occurs first. CR is defined as: * No circulating lymphoblasts * Extramedullary disease negative * Trilineage hematopoiesis (TLH) and \<5% leukemic blasts * Absolute neutrophil count (ANC) ≥1000/μL * Platelets ≥100,000/μL * No platelet transfusions in the last 7 days * No administration of short-acting granulocyte colony-stimulating factor (G-CSF) and long-acting G-CSF in the last 3 and 14 days, respectively CRh is the same as CR but with less stringent requirements for platelet count (≥50,000/μL) and ANC (≥500/μL). CRi is the same as CR but without recovery of platelet count or without recovery of ANC (platelets \<100,000/μL and ANC ≥1000/μL or platelets ≥100,000/μL and ANC \<1000/μL.
Time frame: 3 treatment cycles (up to approximately 126 days; each cycle is up to 42 days; cycle lengths vary between cycle and arm)
Percentage of Participants with CR or CRh in Study Part 2
The percentage of participants who meet either CR or CRh requirements will be presented. CR is defined as: * No circulating lymphoblasts * Extramedullary disease negative * Trilineage hematopoiesis (TLH) and \<5% leukemic blasts * Absolute neutrophil count (ANC) ≥1000/μL * Platelets ≥100,000/μL * No platelet transfusions in the last 7 days * No administration of short-acting granulocyte colony-stimulating factor (G-CSF) and long-acting G-CSF in the last 3 and 14 days, respectively CRh is the same as CR but with less stringent requirements for platelet count (≥50,000/μL) and ANC (≥500/μL).
Time frame: 3 treatment cycles (up to approximately 126 days; each cycle is up to 42 days; cycle lengths vary between cycle and arm)
Duration of CR (DOR-CR) in Study Part 2
For participants who demonstrate CR, duration of remission is defined as the time from the first documented evidence of CR until disease progression, relapse, or death due to any cause, whichever occurs first. CR is defined as: * No circulating lymphoblasts * Extramedullary disease negative * Trilineage hematopoiesis (TLH) and \<5% leukemic blasts * Absolute neutrophil count (ANC) ≥1000/μL * Platelets ≥100,000/μL * No platelet transfusions in the last 7 days * No administration of short-acting granulocyte colony-stimulating factor (G-CSF) and long-acting G-CSF in the last 3 and 14 days, respectively
Time frame: Up to approximately 7 years
Duration of CR/CRh (DOR-CR/CRh) in Study Part 2
For participants who demonstrate CR or CRh, duration of remission is defined as the time from the first documented evidence of CR or CRh (whichever is earlier) until disease progression, relapse, or death due to any cause, whichever occurs first. CR is defined as: * No circulating lymphoblasts * Extramedullary disease negative * Trilineage hematopoiesis (TLH) and \<5% leukemic blasts * Absolute neutrophil count (ANC) ≥1000/μL * Platelets ≥100,000/μL * No platelet transfusions in the last 7 days * No administration of short-acting granulocyte colony-stimulating factor (G-CSF) and long-acting G-CSF in the last 3 and 14 days, respectively CRh is the same as CR but with less stringent requirements for platelet count (≥50,000/μL) and ANC (≥500/μL).
Time frame: Up to approximately 7 years
Duration of CR/CRh/CRi (DOR-CR/CRh/CRi) in Study Part 2
For participants who demonstrate CR or CRh or CRi, duration of remission is defined as the time from the first documented evidence of CR or CRh or CRi (whichever is earlier) until disease progression, relapse, or death due to any cause, whichever occurs first. CR is defined as: * No circulating lymphoblasts * Extramedullary disease negative * Trilineage hematopoiesis (TLH) and \<5% leukemic blasts * Absolute neutrophil count (ANC) ≥1000/μL * Platelets ≥100,000/μL * No platelet transfusions in the last 7 days * No administration of short-acting granulocyte colony-stimulating factor (G-CSF) and long-acting G-CSF in the last 3 and 14 days, respectively CRh is the same as CR but with less stringent requirements for platelet count (≥50,000/μL) and ANC (≥500/μL). CRi is the same as CR but without recovery of platelet count or without recovery of ANC (platelets \<100,000/μL and ANC ≥1000/μL or platelets ≥100,000/μL and ANC \<1000/μL.
Time frame: Up to approximately 7 years
Event Free Survival (EFS) in Study Part 2
The time from randomization to the first documented disease progression, relapse, or death due to any cause, whichever occurs first.
Time frame: Up to approximately 7 years
Percentage of participants that proceed to allogeneic hematopoietic stem cell transplantation (allo-HSCT) in Study Part 2
The use of allo-HSCT treatment after randomization.
Time frame: Up to approximately 7 years
Percentage of Participants Who Experience an AE in Study Part 2
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. The percentage of participants with at least 1 AE will be presented.
Time frame: Up to approximately 7 years
Percentage of Participants Who Discontinue Study Intervention Due to an AE in Study Part 2
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. The percentage of participants who discontinue study intervention due to an AE will be presented.
Time frame: Up to approximately 7 years
Plan to share: Yes — https://trialstransparency.msdclinicaltrials.com/pdf/ProcedureAccessClinicalTrialData.pdf
Data sharing details ↗ · externaldatasharing-msd.com
Started May 2026 (actual). Primary completion is estimated for Oct 2033, 89 months after the start.
How these figures are worked out, and which studies are left out of them.
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.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Studies of the drug tested here: Anti-CD19/CD3 Bispecific Antibody MK-1045