Cladribine + Rituximab for Hairy Cell Leukemia

Palo Alto (17 mi)

Overseen byRobert J Kreitman, M.D.

Age: 18+

Sex: Any

Travel: May be covered

Time Reimbursement: Varies

Trial Phase: Phase 2

Waitlist Available

Sponsor: National Cancer Institute (NCI)

No Placebo Group

Prior Safety Data

Breakthrough Therapy

Trial Summary

What is the purpose of this trial?Background: Hairy cell leukemia (HCL) is highly responsive to but not curable by cladribine (CdA). HCL responds to rituximab, which is not yet standard therapy for HCL. Patients with the CD25-negative variant (HCLv) respond poorly to initial cladribine but do respond to rituximab in anecdotal reports. Deoxycytidine kinase phosphorylates cladribine to CdATP, which incorporates into DNA, leading to DNA strand breaks and inhibition of DNA synthesis. Rituximab is an anti-CD20 monoclonal antibody which induces apoptosis and either complement or antibody dependent cytotoxicity (ADCC or CDC). Patients in complete remission (CR) to cladribine have minimal residual disease (MRD) by immunohistochemistry of the bone marrow biopsy (BMBx IHC), a risk for early relapse. Tests for HCL MRD in blood or marrow include flow cytometry (FACS) or PCR using consensus primers. The most sensitive HCL MRD test is real-time quantitative PCR using sequence-specific primers (RQ-PCR). In studies with limited follow-up, MRD detected by tests other than RQ-PCR can be eliminated by rituximab after cladribine in greater than 90 percent of patients, but MRD rates after cladribine alone are unknown. Simultaneous cladribine and rituximab might be superior or inferior to delaying rituximab until detection of MRD. Only 4 HCL-specific trials are listed on Cancer.gov: a phase II trial of cladribine followed 4 weeks later by 8 weekly doses of rituximab, and phase I-II trials of recombinant immunotoxins targeting CD22 (BL22, HA22) and CD25 (LMB-2). Objectives: Primary: To determine if HCL MRD differs at 6 months after cladribine with or without rituximab administered concurrently with cladribine. Secondary: * To compare cladribine plus rituximab vs cladribine alone in terms of 1) initial MRD-free survival and disease-free survival, and 2) response to delayed rituximab for relapse, to determine if early rituximab compromises later response. * To determine if MRD levels and tumor markers (soluble CD25 and CD22) after cladribine and/or rituximab correlate with response and clinical endpoints. * To determine, using MRD and tumor marker data, when BMBx can be avoided. * To compare response and MRD after the 1st and 2nd courses of cladribine. * To evaluate the effects of cladribine and rituximab on normal T- and B-cells. * To enhance the study of HCL biology by cloning, sequencing and characterizing monoclonal immunoglobulin rearrangements. Eligibility: HCL with 0-1 prior courses of cladribine and treatment indicated. Design: Cladribine 0.15 mg/Kg/day times 5 doses each by 2hr i.v. infusion (days 1-5) Rituximab 375 mg/m2/week times 8 weeks, randomized half to begin day 1, then repeat for all patients with blood-MRD relapse at least 6 months after cladribine. Also may repeat for those with blood-MRD relapse at least 6 months after delayed rituximab. MRD tests used for the primary objective will be limited to BMBx IHC, blood FACS or blood consensus PCR, all CLIA certified. Blood MRD relapse is defined as FACS positivity or low blood counts (ANC less than 1500/microl, Plt less than 100,000/microl, or Hgb less than 11). Stratification: 68 patients with 0 and 62 with 1 prior course of cladribine. Statistics: 80% power to discriminate rates of MRD of 5 vs 25%, or 10 vs 35% Non-randomized arm: 20 with HCLv will begin rituximab with cladribine. Accrual Ceiling: 152 patients (130 HCL, 2 extra HCL if needed, and 20 HCLv.)

Eligibility Criteria

This trial is for adults with Hairy Cell Leukemia (HCL) who have had no more than one prior treatment with cladribine. Participants should not be pregnant, must agree to use birth control, and cannot have untreated infections or certain other health conditions. Those with the variant form of HCL (HCLv) may also join even if they've had rituximab before.

Inclusion Criteria

I can care for myself but may not be able to do heavy physical work.

My kidney function, measured by creatinine levels, is normal.

I am 18 years old or older.

I agree to use birth control during and for a year after treatment.

I have not had rituximab unless I have variant hairy cell leukemia.

Treatment Details

The study tests whether giving rituximab at the same time as cladribine is better than waiting until after cladribine treatment when minimal residual disease (MRD) might be detected. Patients will either receive both drugs simultaneously or just cladribine first, followed by rituximab later if MRD appears.

3Treatment groups

Experimental Treatment

Active Control

Group I: 3Experimental Treatment2 Interventions

Non-randomized group receving Cladribine with immediate Rituximab (before rather than after the 1st of the 5 daily doses of cladribine on day 1)

Group II: 1Experimental Treatment2 Interventions

Cladribine with immediate Rituximab

Group III: 2Active Control2 Interventions

Cladribine with Rituximab delayed by at least 6 months after Cladribine if and when minimal residual disease is detected

Cladribine is already approved in United States, European Union for the following indications:

🇺🇸 Approved in United States as Leustatin for: