NCT06849713 · Massachusetts General Hospital
Zanubrutinib, Obinutuzumab, and Sonrotoclax in Previously Untreated Patients With CLL or SLL
(BOSon)
What this study is about
The purpose of this study is to determine the proportion of participants who achieve undetectable measurable residual disease (uMRD) in previously untreated chronic lymphocytic leukemia (CLL) or small lymphocytic lymphoma (SLL).
View original scientific description
The purpose of this study is to determine the proportion of participants who achieve undetectable measurable residual disease (uMRD) in previously untreated chronic lymphocytic leukemia (CLL) or small lymphocytic lymphoma (SLL).
Interventions
DRUG
Zanubrutinib
Bruton's Tyrosine Kinase (BTK) inhibitor
DRUG
Sonrotoclax
B-cell lymphoma 2 (BCL2) protein inhibitor
DRUG
Obinutuzumab
Anti-CD20 monoclonal antibody
DRUG
Tacabrutideg
Bruton's Tyrosine Kinase (BTK) degrader
Primary outcome measures
Rate of Undetectable MRD (uMRD) at Best Response
Time frame: Day 1 to 2 years after final patient enrolled
The proportion of patients achieving undetectable MRD in peripheral blood using the ClonoSEQ assay (cutoff, \<10-5). The number of responses will be reported with a proportion with 95% exact binomial confidence interval.
Proportion of Participants with Tumor Lysis Syndrome (TLS) Laboratory Abnormalities Requiring Intervention
Time frame: Day 1 to completion date of sonrotoclax ramp-up
The proportion of participants who have 1 or more TLS laboratory abnormalities requiring intervention on a ramp-up date with normal pre-dose TLS parameters and ALC \<25,000/µl during the sonrotoclax ramp-up. The number of responses will be reported with a proportion with 95% exact binomial confidence interval.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Participant must have CLL or SLL (WHO criteria).
- Participant must require treatment according to iwCLL guidelines.
- Participants must have no prior systemic therapy for CLL or SLL, except:
- Prior local radiation for symptomatic disease is permitted.
- Short course systemic corticosteroids is permissible for disease control, improvement of performance status, or non-cancer indication. However, duration of steroid course must be ≤14 days with maximum daily dose of ≤100 mg prednisone, ≤20 mg dexamethasone, or equivalent, and must be discontinued prior to study treatment (last dose may be administered up until the morning of / prior to study treatment). Inhaled steroids, topical steroids, and replacement / stress corticosteroids are permitted independent of above rules. In cases of autoimmune complications of CLL (e.g., ITP or AIHA), steroid usage is permitted.
- Age ≥18 years.
- ECOG performance status of 0, 1 or 2.
- Participants must meet the following or
Where
- Boston, Massachusetts
- New York, New York
Collaborators
BeOne Medicines
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Aug 11, 2026 · Source of record for eligibility and locations