A Phase 2 interventional study of Pirtobrutinib and Obinutuzumab in Chronic Lymphocytic Leukemia and Small Lymphocytic Lymphoma, sponsored by Inhye Ahn. Recruiting at 4 sites in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-01-21.
Sponsored by Inhye Ahn · Phase 2, Interventional, and Treatment
This study will evaluate fixed-duration therapy with pirtobrutinib and obinutuzumab given over 12 cycles (approximately 1 year) as first-line treatment of chronic lymphocytic leukemia or small lymphocytic lymphoma (CLL or SLL).
This is an open-label, multicenter, single-arm phase 2 study of pirtobrutinib with obinutuzumab for participants with CLL or SLL. Eligible participants will receive 6 cycles of pirtobrutinib alone followed by an additional 6 cycles of pirtobrutinib-obinutuzumab combination therapy. All participants will stop treatment after 12 cycles in total (approximately 1 year).
If CLL progresses and requires treatment after 1-year of therapy, participants will receive retreatment with pirtobrutinib only. Participants will be followed for up to a total of 10 years. Up to 60 participants will take part in this study.
The U.S. Food and Drug Administration (FDA) has approved pirtobrutinib for continuous treatment of CLL that has relapsed or become refractory to other treatments. Pirtobrutinib is not approved for the first-line treatment of CLL/SLL nor for fixed-duration therapy. The FDA has approved obinutuzumab for the treatment of CLL.
The research study procedures include screening for eligibility, study treatment visits, electrocardiograms, imaging (e.g. computerized tomography or CT scans), blood tests, saliva tests, bone marrow biopsies, and/or lymph node biopsies (if feasible).
Loxo Oncology at Eli Lilly and Company is supporting this study by providing pirtobrutinib and research funding.
1,603 studies on the registry are indexed under Leukemia, Lymphocytic, Chronic, B-Cell; 243 are open to participants now.
This study's planned enrollment of 60 is above the median of 40 across 1,325 interventional studies indexed under Leukemia, Lymphocytic, Chronic, B-Cell.
Browse Leukemia, Lymphocytic, Chronic, B-Cell studies →Inhye Ahn is the lead sponsor of 3 studies on the registry; 2 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Key Inclusion Criteria:
Key Exclusion Criteria:
Eligible participants will receive initial treatment with pirtobrutinib and obinutuzumab for 12 cycles. Participants with progressive chronic lymphocytuc leukemia or small lymphocytic lymphoma during the off-treatment follow-up will receive continuous pirtobrutinib monotherapy.
Drug: Pirtobrutinib · Drug: Obinutuzumab
Initial treatment: \- Pirtobrutinib 200 mg by mouth (PO) daily from Cycle 1 Day 1 until the end of Cycle 12. Each cycle is 28 days. Re-treatment: -Pirtobrutinib 200 mg PO daily continuously
Obinutuzumab is given intravenously from Cycle 7 to Cycle 12, for total 6 cycles during initial treatment only. Initial treatment: \- Obinutuzumab intravenous (IV) following the standard schedule from Cycle 6 through Cycle 12 (total 6 cycles: 100 mg on Cycle 6 Day 1, 900 mg on Cycle 6 Day 2, 1000 mg on Cycle 6 Day 8 and Cycle 6 Day 15, 1000 mg on Day 1 of Cycle 7 through Cycle 12).
Rate of complete response after initial therapy
Defined by the 2018 International Workshop on Chronic Lymphocytic Leukemia (IWCLL) guidelines
Time frame: 1 year since treatment initiation
Overall response rate
Defined by the 2018 IWCLL guidelines
Time frame: 1 year since treatment initiation
Rate of partial response
Defined by the 2018 IWCLL guidelines
Time frame: 1 year since treatment initiation
Time to next line of therapy
Time from the initiation of study therapy until the next line of therapy (excluding pirtobrutinib re-treatment)
Time frame: 5 years after the last enrollment
Event-free survival
Time from the initiation of study therapy until pre-defined events (progression, death, or start of a new treatment)
Time frame: 5 years after the last enrollment
Progression-free survival
Time from the initiation of study therapy until disease progression or death
Time frame: 5 years after the last enrollment
Overall survival
Time from the initiation of study therapy until death
Time frame: 5 years after the last enrollment
Rate of re-treatment with pirtobrutinib
Rate of re-treatment with pirtobrutinib on study
Time frame: 5 years after the last enrollment
Plan to share: Yes — The Dana-Farber / Harvard Cancer Center encourages and supports the responsible and ethical sharing of data from clinical trials. De-identified participant data from the final research dataset used in the published manuscript may only be shared under the terms of a Data Use Agreement.
Supporting information: Study protocol, Sap
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Leukemia, Lymphocytic, Chronic, B-Cell→
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