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Cladribine With Simultaneous or Delayed Rituximab to Treat Hairy Cell Leukemia

Phase 2
Active, not recruiting
Conditions
Hairy Cell Leukemia
Interventions
Procedure: BMbx
Diagnostic Test: MRI
Diagnostic Test: EKG
Diagnostic Test: Echocardiogram
Diagnostic Test: Abdominal/splenic ultrasound
Procedure: Stress test
Registration Number
NCT00923013
Lead Sponsor
National Cancer Institute (NCI)
Brief Summary

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 interleukin 2 (IL-2) receptor (CD25)-negative hairy cell leukemia variant (HCLv) respond poorly to initial cladribine but do respond to rituximab in anecdotal reports.

Deoxycytidine kinase phosphorylates cladribine to chlorodeoxyadenosine triphosphate (CdATP), which incorporates into deoxyribonucleic acid (DNA), leading to DNA strand breaks and inhibition of DNA synthesis. Rituximab is an anti-cluster of differentiation 20 (CD20) monoclonal antibody which induces apoptosis and either complement or antibody dependent cytotoxicity (antibody-dependent cellular cytotoxicity (ADCC) or complement-dependent cytotoxicity (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 fluorescence-activated cell sorting (FACS) or polymerase chain reaction (PCR) using consensus primers. The most sensitive HCL MRD test is real-time quantitative PCR using sequence-specific primers real-time quantitative reverse transcriptase polymerase chain reaction (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 cluster of differentiation-22 (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 bone marrow biopsy (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 2hour(hr) intravenous (i.v.) infusion (days 1-5)

Rituximab 375 mg/m\^2/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 Clinical Laboratory Improvement Amendments (CLIA) certified. Blood MRD relapse is defined as FACS positivity or low blood counts (ANC less than 1500/microl, platelet (Plt) less than 100,000/microl, or hemoglobin (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.)

Detailed Description

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 interleukin 2 (IL-2) receptor (CD25)-negative hairy cell leukemia variant (HCLv) respond poorly to initial cladribine but do respond to rituximab in anecdotal reports.

Purine analogs cladribine and pentostatin have similar efficacy for HCL, both inhibiting deoxyribonucleic acid (DNA) synthesis selectively in HCL cells. Cladribine is effective after just 1 cycle. Rituximab is an anti-cluster of differentiation 20 (CD20) monoclonal antibody which induces apoptosis and either complement or antibody dependent cytotoxicity (antibody-dependent cellular cytotoxicity (ADCC) or complement-dependent cytotoxicity (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 fluorescence-activated cell sorting (FACS) or polymerase chain reaction (PCR) using consensus primers. The most sensitive HCL MRD test is real-time quantitative PCR using sequence-specific primers real-time quantitative reverse transcriptase polymerase chain reaction (RQ-PCR).

In studies with limited follow-up, MRD detected by tests other than RQ-PCR can be eliminated by rituximab after cladribine in \> 90% of patients, but MRD rates after purine analog 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 cluster of differentiation-22 (CD22) (BL22, HA22) and CD25 (LMB-2).

Objective:

To determine if HCL MRD differs at 6 months after cladribine with or without rituximab administered concurrently with cladribine.

Eligibility:

HCL with 0-1 prior courses of cladribine or pentostatin and treatment indicated.

Design:

Cladribine 0.15 mg/Kg/day times 5 doses each by 2hour(hr) intravenous (i.v.) infusion (days 1-5)

Rituximab 375 mg/m\^2/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, and

bone marrow aspirate FACS, all Clinical Laboratory Improvement Amendments (CLIA) certified. Blood MRD relapse is defined as FACS positivity or low blood counts (absolute neutrophil count (ANC) less than 1500/microl, platelet (Plt) less than 100,000/microl, or hemoglobin (Hgb) less than 11) attributed to HCL. Patients FACS-negative in both blood and bone marrow aspirate are considered MRD-negative complete response (CR) regardless of blood counts.

Randomization: 68 HCL patients with 0 and 62 with 1 prior course of purine analog

Statistics: 80% power to discriminate rates of MRD of 5 vs. 25%, or 10 vs. 35%

Non-randomized HCLv arm: 20 patients with HCLv will begin rituximab with cladribine.

Non-randomized HCL arm: 25 newly diagnosed patients will be enrolled to receive rituximab

beginning day 1, but beginning before the 1st dose of cladribine, rather than after.

Accrual ceiling: 175 evaluable patients (155 HCL and 20 HCLv)

Recruitment & Eligibility

Status
ACTIVE_NOT_RECRUITING
Sex
All
Target Recruitment
175
Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
1/Cladribine with immediate RituximabCladribineCladribine with immediate Rituximab.
1/Cladribine with immediate RituximabRituximabCladribine with immediate Rituximab.
1/Cladribine with immediate RituximabBMbxCladribine with immediate Rituximab.
1/Cladribine with immediate RituximabMRICladribine with immediate Rituximab.
1/Cladribine with immediate RituximabEKGCladribine with immediate Rituximab.
1/Cladribine with immediate RituximabEchocardiogramCladribine with immediate Rituximab.
1/Cladribine with immediate RituximabAbdominal/splenic ultrasoundCladribine with immediate Rituximab.
1/Cladribine with immediate RituximabStress testCladribine with immediate Rituximab.
2/Cladribine with Rituximab Delayed by at Least 6 months After CladribineCladribineCladribine with Rituximab delayed by at least 6 months after Cladribine if and when minimal residual disease is detected.
2/Cladribine with Rituximab Delayed by at Least 6 months After CladribineRituximabCladribine with Rituximab delayed by at least 6 months after Cladribine if and when minimal residual disease is detected.
2/Cladribine with Rituximab Delayed by at Least 6 months After CladribineBMbxCladribine with Rituximab delayed by at least 6 months after Cladribine if and when minimal residual disease is detected.
2/Cladribine with Rituximab Delayed by at Least 6 months After CladribineMRICladribine with Rituximab delayed by at least 6 months after Cladribine if and when minimal residual disease is detected.
2/Cladribine with Rituximab Delayed by at Least 6 months After CladribineEKGCladribine with Rituximab delayed by at least 6 months after Cladribine if and when minimal residual disease is detected.
2/Cladribine with Rituximab Delayed by at Least 6 months After CladribineEchocardiogramCladribine with Rituximab delayed by at least 6 months after Cladribine if and when minimal residual disease is detected.
2/Cladribine with Rituximab Delayed by at Least 6 months After CladribineAbdominal/splenic ultrasoundCladribine with Rituximab delayed by at least 6 months after Cladribine if and when minimal residual disease is detected.
2/Cladribine with Rituximab Delayed by at Least 6 months After CladribineStress testCladribine with Rituximab delayed by at least 6 months after Cladribine if and when minimal residual disease is detected.
3/Non-randomized Group Receiving Cladribine with Immediate RituximabCladribineNon-randomized group receiving Cladribine with immediate Rituximab (before rather than after the 1st of the 5 daily doses of cladribine on day 1).
3/Non-randomized Group Receiving Cladribine with Immediate RituximabRituximabNon-randomized group receiving Cladribine with immediate Rituximab (before rather than after the 1st of the 5 daily doses of cladribine on day 1).
3/Non-randomized Group Receiving Cladribine with Immediate RituximabBMbxNon-randomized group receiving Cladribine with immediate Rituximab (before rather than after the 1st of the 5 daily doses of cladribine on day 1).
3/Non-randomized Group Receiving Cladribine with Immediate RituximabMRINon-randomized group receiving Cladribine with immediate Rituximab (before rather than after the 1st of the 5 daily doses of cladribine on day 1).
3/Non-randomized Group Receiving Cladribine with Immediate RituximabEKGNon-randomized group receiving Cladribine with immediate Rituximab (before rather than after the 1st of the 5 daily doses of cladribine on day 1).
3/Non-randomized Group Receiving Cladribine with Immediate RituximabEchocardiogramNon-randomized group receiving Cladribine with immediate Rituximab (before rather than after the 1st of the 5 daily doses of cladribine on day 1).
3/Non-randomized Group Receiving Cladribine with Immediate RituximabAbdominal/splenic ultrasoundNon-randomized group receiving Cladribine with immediate Rituximab (before rather than after the 1st of the 5 daily doses of cladribine on day 1).
3/Non-randomized Group Receiving Cladribine with Immediate RituximabStress testNon-randomized group receiving Cladribine with immediate Rituximab (before rather than after the 1st of the 5 daily doses of cladribine on day 1).
Primary Outcome Measures
NameTimeMethod
Response Rate Comparing Minimal Residual Disease (MRD) at 6 Months After Start of Treatment in Comparison GroupsRestaged 6 months after the start of treatment

Participants with newly diagnosed Hairy Cell Leukemia (HCL) and once relapsed HCL were split and both groups were randomized to receive either simultaneous treatment with Cladribine and Rituxan or Cladribine with Rituxan given no earlier than 6 months after cladribine as needed. Outcome measured by Bone Marrow and Blood Flow cytometry and histochemistry of the core biopsy at the 6 months after start of treatment time point. If all three were negative for hairy cells participants were in a minimal residual disease status (MRD). And were considered without HCL disease at that time point.

Secondary Outcome Measures
NameTimeMethod
Minimal Residual Disease (MRD)-Free Survival After Cladribine and up to 2 Courses of RituximabTesting done 6 months post first dose of treatment, then yearly x2 years and then every 2 years after cladribine indefinitely

Compare Cladribine + Rituxan vs cladribine alone in terms of MRD-free survival. MRD free survival time is the time until relapsing from MRD to -free to Complete response. Measured by blood and bone marrow flow cytometry, complete blood count (CBC), and bone marrow immunohistochemistry.

Trial Locations

Locations (1)

National Institutes of Health Clinical Center

🇺🇸

Bethesda, Maryland, United States

National Institutes of Health Clinical Center
🇺🇸Bethesda, Maryland, United States

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