Hairy Cell LeukemiaPhase 1NCT03805932
Moxetumomab Pasudotox-tdfk (Lumoxiti(TM)) and Either Rituximab (Rituxan(R)) or Ruxience for Relapsed Hairy Cell Leukemia
A Phase 1 study testing Moxetumomab Pasudotox-tdfk, Rituximab and Ruxience in people with Hairy Cell Leukemia, run by National Cancer Institute (NCI) at 1 site in United States.
Trial summary
Background: Hairy cell leukemia (HCL) is a rare, slow-growing blood cancer in which the bone marrow makes too many of certain white blood cells. The antibody Rituximab/Ruxience binds to a protein in cancerous white blood cells and is often used to treat HCL. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Hairy Cell Leukemia
- What is being tested?
- Moxetumomab Pasudotox-tdfk, Rituximab and Ruxience
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 18 participants
- Where
- 1 siteUnited States
- Study dates
- 3 Oct 2019to 30 Jun 2029
- Phase
- Phase 1
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Diagnosis of hairy cell leukemia (HCL) or Hairy cell leukemia variant (HCLv).
- Treatment required for either 1) Absolute neutrophil count (ANC) <1/nL, 2) Hemoglobin <10g/dL, 3) Platelets<100/nL, 4) symptomatic splenomegaly, or 5) enlarging HCL mass > 2cm in short axis. Patients who have eligible blood counts within 4 weeks from the initiation of study will not be considered ineligible if subsequent blood counts prior to enrollment fluctuate and become ineligible up until the time of enrollment.
- Patients must be Pseudomonas-immunotoxin naive.
- HCL or HCLv with at least 1 prior purine analog, and, for HCL patients with >=2-years 1 month response, at least 1 other therapy. Age greater than or equal to 18 years as the disease under study, HCL/HCLv, has not been reported in children < age 18.
- Eastern Cooperative Oncology Group (ECOG) performance status less than or equal to2 (Karnofsky greater than or equal to 60%)
- Patients must have adequate organ and marrow function as defined below:
Show all 18Show fewer
- Total bilirubin less than or equal to 1.5 mg/dL, unless consistent with Gilbert's (ratio between total and direct bilirubin > 5)
- Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) less than or equal to 3x upper limit of normal (ULN)
- Alkaline phosphatase < 2.5 ULN
- Serum creatinine less than or equal to 1.5 mg/dL or creatinine clearance greater than or equal to 60 mL/min by Cockcroft-Gault equation, where creatinine clearance = (140-age)(Kg weight)/(72 x Creatinine)
- Serum albumin greater than or equal to 2 g/dL
- Partial thromboplastin time (PTT) or Prothrombin time (PT)/International Normalized Ratio < 2.5x ULN (If on warfarin, PT/INR < 3.5x ULN; If on any other anticoagulation, Prothrombin time (PT) < 2.5x baseline)
- Fibrinogen greater than or equal to 0.5 lower limit of normal
- The effects of moxetumomab pasudotox-tdfk and rituximab/Ruxience on the developing human fetus are unknown therefore participants must use effective methods of contraception as directed below.
- Females of childbearing potential (< 50 years) who are sexually active with a non-sterilized male partner must use a highly effective method of contraception prior to study entry and or the duration of study participation and must agree to continue using such precautions for 12 months after completion of rituximab/Ruxience administration. Contraception after this point should be discussed with a responsible physician. Periodic abstinence, the rhythm method, and the withdrawal method are not acceptable methods of contraception. Females of childbearing potential are defined as those who are not surgically sterile (i.e., bilateral tubal ligation, bilateral oophorectomy, or complete hysterectomy) or those who are premenarchal or postmenopausal (defined as 12 months with no menses without an alternative medical cause). A highly effective method of contraception is defined as one that results in a low failure rate (i.e., less than 1% per year) when used consistently and correctly. Not all methods of contraception are highly effective. Should a woman become pregnant or suspect she is pregnant while she or her partner is participating in this study, she should inform her treating physician immediately.
- Non-sterilized males who are sexually active with a female partner of childbearing potential must use an effective method of contraception from Day 1 until 90 days after receipt of the final dose of investigational product. It is required that a female partner of a male subject also use an effective method of contraception throughout this period.
- Ability of subject to understand and the willingness to sign a written informed consent document.
- Patients must be willing to co-enroll in the investigators companion protocol 10C-0066 titled Collection of Human Samples to Study Hairy Cell and other Leukemias, and to Develop Recombinant Immunotoxins for Cancer Treatment.
Who cannot join
- Patients who have had chemotherapy, immunotherapy or radiotherapy within 4 weeks or treatment with rituximab/Ruxience within last 3 months prior to initiation of treatment.
- Patients who are receiving any other investigational agents.
- Breastfeeding within the projected duration of the study, starting with the screening visit through 6 months after the last dose of rituximab/Ruxience. Pregnant women are excluded from this study because moxetumomab pasudotox-tdfk and rituximab/Ruxience are agents with the potential for teratogenic or abortifacient effects. Because there is an unknown but potential risk for adverse events in nursing infants secondary to treatment of the mother with moxetumomab pasudotox-tdfk and rituximab/Ruxience, breastfeeding should be discontinued if the mother is treated with moxetumomab pasudotox-tdfk and rituximab/Ruxience.
- Patients with known brain metastases should be excluded from this clinical trial because of their poor prognosis and because they often develop progressive neurologic dysfunction that would confound the evaluation of neurologic and other adverse events.
- Uncontrolled intercurrent illness including, but not limited to, ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, uncontrolled hypertension, uncontrolled pulmonary infection, pulmonary edema or psychiatric illness/social situations that would limit compliance with study requirements.
- Patients with retinal or choroidal detachment.
Show all 19Show fewer
- Positive for Hepatitis B core antibody or surface antigen unless the patient is on Tenofovir or Entecavir and Hepatitis B Viral deoxyribonucleic acid (DNA) load is <2000 IU/mL
- Active second malignancy requiring treatment other than minor resection of indolent cancers like basal cell and squamous skin cancers.
- Human immunodeficiency virus (HIV)-positive patients unless taking appropriate anti-HIV medications with a cluster of differentiation 4 (CD4) count of > 200. Otherwise, there may be an increased risk of lethal infections when temporarily suppressing normal B-cells.
- History of an allogeneic bone marrow transplant.
- Patients with a history of both thromboembolism and known congenital hypercoagulable conditions.
- Radioimmunotherapy within 2 years prior to enrollment in the study.
- Patients with history of thrombotic microangiopathy or thrombotic microangiopathy/hemolytic uremic syndrome (HUS).
- Patients with corrected QT interval (Frederica) elevation > 500 msec (manually over-read by medically qualified person) based on at least two separate 12-lead ECGs.
- Patients on high dose estrogen (defined as > 0.625 mg/day of an estrogen compound).
- Oxygen saturation at rest < 88% measured by pulse oximetry or partial pressure of oxygen (PaO2) less than or equal to 55 mm Hg.
- Patients with life expectancy of less than 6 months.
- Patients with clinical evidence of disseminated intravascular coagulation (Grade 3-4).
- Patients with < 50% of predicted forced expiratory volume (FEV1) or < 50% of predicted diffusing capacity for carbon monoxide, corrected for hemoglobin concentration and alveolar volume (DLCO). Note: Patients with no prior history of pulmonary illness are not required to have pulmonary function testing (PFT). Forced expiratory volume will be assessed after bronchodilator therapy.
Trial locations and contacts
1 site in 1 country.
United States1 site
National Institutes of Health Clinical Center
Bethesda, Maryland, 20892
About this study
Official title: A Phase I Study of Moxetumomab Pasudotox-tdfk (Lumoxiti (TM)) and Either Rituximab (Rituxan (R)) or Ruxience for Relapsed Hairy Cell Leukemia
Background:
Hairy cell leukemia (HCL) is a rare, slow-growing blood cancer in which the bone marrow makes too many of certain white blood cells. The antibody Rituximab/Ruxience binds to a protein in cancerous white blood cells and is often used to treat HCL. Researchers want to see if combining it with the drug Moxetumomab pasudotox-tdfk (also called Lumoxiti) can fight HCL better.
Read more
Objective:
To test the safety of Moxetumomab pasudotox taken with Rituximab/Ruxience for people with HCL or HCL variant.
Eligibility:
People age 18 years and older with HCL or HCL variant that has not responded to standard therapy
Design:
Participants will be screened with:
Medical history
Physical exam
Blood, heart, and urine tests
Test of blood oxygen levels
Review of bone marrow. This can be from previous test results or a new sample.
Scans
Exercise test
Participants will get the study drugs in up to 8 cycles. A cycle will last about 28 days.
The study drugs will be given through a plastic tube in a vein.
In the first week of cycle 1, participants will have:
1 visit to get Rituximab or Ruxience for 7.5 hours
3 visits to get Lumoxiti for 30 minutes per infusion
In the first week of cycles 2-8, participants will have:
- visit to get Rituximab/Ruxience for 2-4 hours and Lumoxiti for 30 minutes
- visits to get Lumoxiti for 30 minutes per infusion
Participants will be asked to drink lots of water and take aspirin during the cycles. They will get drugs to minimize allergic reactions.
Participants will repeat screening tests at visits throughout the cycles and 1 follow-up visit. They may have an eye exam.
...
Read the detailed description
Background:
- Hairy cell leukemia (HCL) is an indolent cluster of differentiation-22 (CD22+) B-cell leukemia comprising 2% of all leukemias, or approximately 1200 of the 62,130 new cases of leukemia/year in the United States (US). HCL variant (HCLv), also CD22+, is 10-20% as common as HCL, but more common in the relapsed/refractory population due to its poor prognosis and response to standard purine analog chemotherapy. hairy cell leukemia variant (HCL-V) cells are cluster of Differentiation 25 (CD25)-negative and wild type for BRAF, so HCLv patients are not candidates for BRAF inhibitors. CD25+ classic-appearing HCL-cells that express unmutated IGHV4-34 (Immunoglobulin Heavy Variable 4-34) are wild-type for BRAF, remain brightly CD22 positive, and confer a poor prognosis when treated with chemotherapy.
- Moxetumomab pasudotox-tdfk is a recombinant immunotoxin containing a variable domain (Fv) fragment of an anti-CD22 monoclonal antibody and truncated Pseudomonas exotoxin, which kills CD22+ cells by binding to CD22 via the (Fv) fragment, and induction of apoptotic cell death catalytic inhibition of protein synthesis in the cytosol.
- Moxetumomab pasudotox-tdfk in phase 1 testing demonstrated a high complete response (CR) rate in patients with chemoresistant HCL, without dose-limiting toxicity (DLT), but with reversible grade 2 hemolytic uremic syndrome (HUS) not requiring plasmapheresis.
- Moxetumomab pasudotox-tdfk completed multicenter phase 3 testing in 80 patients, meeting its complete response (CR) endpoint, with 8.8% incidence each of capillary leak syndrome (CLS, grade 3-4 2.5%), and HUS (grade 3-4 6.3%), both reversible.
- Moxetumomab pasudotox-tdfk is the only known non-chemotherapy-containing regimen for HCL which can consistently eradicate minimal residual disease (MRD), and this is associated with prolonged CR durations. Recently, US Food and Drug Administration (FDA) has accepted the Biologics License Application (BLA) for moxetumomab pasudotox-tdfk as the treatment of adult patients with HCL.
- Patients who did not achieve CR, or CR with MRD, often made neutralizing antibodies to the bacterial-based toxin, and/or had collections of HCL cells not completely eradicated by Moxetumomab pasudotox-tdfk. Both issues may be addressed by the addition of anti-cluster of differentiation 20 (CD20) monoclonal antibody (Mab) rituximab or Ruxience to Moxetumomab pasudotox-tdfk.
Objective:
-To determine the safety and toxicity of Moxetumomab pasudotox-tdfk and rituximab/Ruxience used at the planned dose level, in patients with HCL and HCLv.
Eligibility:
- HCL or HCLv with at least 1 prior purine analog, and, for HCL patients with >=2-years 1 month response, at least 1 other therapy.
- Need for treatment, either 1) absolute neutrophil count (ANC) <1/nL, 2) hemoglobin (Hgb) <10g/dL, 3) platelet (Plt) <100/nL, 4) symptomatic splenomegaly, or enlarging HCL mass > 2cm in short axis
- Serum creatinine < 1.5 mg/dL, or creatinine clearance greater than or equal to 60 mL/min by Cockcroft-Gault equation, where creatinine clearance = (140-age)(kg weight)/(72 x Creatinine).
- No uncontrolled infection or cardiopulmonary dysfunction
Design:
- Phase I trial, two arm, non-randomized, dose escalation
- Administration:
- Patients 1-13: Moxetumomab pasudotox-tdfk 30-40 mcg/kg intravenous (iv) over 30 min, Rituximab 375 mg/m^2 iv, 50-400 mg/hr.
- Patients 14-26: Moxetumomab pasudotox-tdfk 40 mcg/kg intravenous (iv) over 30 min, Ruxience 375 mg/m2 iv, 50-400 mg/hr
- Rituximab or Ruxience day 1 (begin day -2 on cycle 1), Moxetumomab pasudotox-tdfk days 1, 3, and 5.
- Patients will receive up to 4 cycles past documentation of CR without MRD, maximum 8.
- To prevent renal toxicity and hypovolemia, patients will be encouraged to drink water gradually, approximately 0.5-1 cup/hour or 6L/day, not going >3 hours without drinking from days 1 to 8 and to keep a hydration diary to record daily fluid consumption.
- To prevent rituximab/Ruxience toxicity, patients will receive prophylactic dexamethasone orally 0.5- 2 hours before the 1st dose of rituximab, and before subsequent doses until rituximab/Ruxience infusion reactions are not seen. Patients will also receive diphenhydramine, famotidine, and acetaminophen.
- Dexamethasone 4 mg orally (maximum 2 doses/day) will be given as needed to treat nausea or fever associated with Moxetumomab pasudotox-tdfk, which might prevent adequate water intake
- Statistical design:
- Up to 26 patients are intended to be treated in the trial. While a total of 26 evaluable patients will be enrolled, the accrual ceiling will be set at 30 to include screen failures and inevaluable patients.
- Conditions
- Hairy Cell Leukemia
- Being tested
- Moxetumomab Pasudotox-tdfk, Rituximab, Ruxience, Dexamethasone, Acetaminophen
- Keywords
- HCL Variant, Recombinant Immunotoxin, Monoclonal Antibody, Targeted Therapy, Biologic Therapy
- Medical subject headings
- Leukemia, Hairy Cell
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Moxetumomab Pasudotox-tdfkDrug
Also called Lumoxiti
Moxetumomab pasudotox-tdfk is administered at 30-40 ug/Kg intravenous (iv) over 30 min given on days 1, 3, 5 of each cycle.
RituximabBiological
Also called Rituxan
Rituximab will be administered at 375mg/m^2 intravenous (iv), 50-400 mg/hour (hr). On cycle 1, Rituximab is given on day -2, on subsequent cycles, Rituximab is given on day 1.
RuxienceBiological
Also called Rituximab-pvvr
Ruxience will be administered at 375mg/m^2 intravenous (iv), 50-400 mg/hour (hr). On cycle 1, Ruxience is given on day -2, on subsequent cycles, Ruxience is given on day 1 (Delta)
DexamethasoneDrug
Also called Ozurdex, Maxidex, DexPak 6 Day
12 mg Cycle 1, Day -2; Cycles 2-8, Day 1. Administer 0.5-2 hours before rituximab/Ruxience. If participant has previous reaction to rituximab/Ruxience, give 12mg. If participants tolerate rituximab/Ruxience without problems, may hold at discretion of provider. Pre-medications are given prior to rituximab/Ruxience on day 1.
AcetaminophenDrug
Also called Tylenol, Ofirmev, FeverAll
650 mg Cycle 1, Day -2, Day 1, Day 3, Day 5. To be given 30-90 minutes prior to every moxetumomab pasudotox-tdfk infusion and recommended every 6 hours x 4 after the end of infusion; Cycles 2-8, Day 1, Day 3, Day 5. To be given 30-90 minutes prior to every moxetumomab pasudotox-tdfk infusion and recommended every 6 hours x 4 after the end of infusion. Pre-medications are given prior to rituximab/Ruxience on day 1.
DiphenhydramineDrug
Also called Benadryl, Nytol, Banophen
25-50 mg Cycle 1, Day -2; Cycles 2-8, Day 1. Pre-medications are given prior to rituximab/Ruxience on day 1. May be given prior to moxetumomab pasudotox-tdfk at discretion of principal investigator.
FamotidineDrug
Also called Pepcid AC, Pepcid, Acid Controller
20-40 mg Cycle 1, Day -2; Day 1, Day 3, Day 5. To be given 30-90 minutes prior to every moxetumomab pasudotox-tdfk infusion and is recommended every 12 hours x 2 after the end of infusion; Cycles 2-8, Day 1, Day 3, Day 5. To be given 30-90 minutes prior to every moxetumomab pasudotox-tdfk infusion and is recommended every 12 hours x 2 after the end of infusion. Pre-medications are given prior to rituximab/Ruxience on day 1.
AspirinDrug
Also called Ecotrin, Enteric Coated Aspirin, Buffered Aspirin
81 mg Cycle 1, Days 1-8; Cycles 2-8, Days 1-8. Only if platelet counts ≥ 100 x 109/L.
| Study group | Role | What they receive |
|---|---|---|
| Moxetumomab - Dose Escalation 30 mcg/kg | Experimental | Arm 1 Moxetumomab Pasudotox-tdfk + Rituximab Receives: Drug: Moxetumomab Pasudotox-tdfk; Biological: Rituximab; Drug: Dexamethasone; Drug: Acetaminophen; Drug: Diphenhydramine; Drug: Famotidine; Drug: Aspirin |
| Moxetumomab - Dose Expansion 40 mcg/kg | Experimental | Arm 1 and Arm 2 Moxetumomab Pasudotox-tdfk + Ruxience Receives: Drug: Moxetumomab Pasudotox-tdfk; Biological: Ruxience; Drug: Dexamethasone; Drug: Acetaminophen; Drug: Diphenhydramine; Drug: Famotidine; Drug: Aspirin |
What is being measured
The primary outcome is the main question the study is designed to answer.
Recommended Safe Dose of Moxetumomab Pasudotox-tdfk
Recommended safe dose of moxetumomab pasudotox-tdfk is defined as the treatment of 10 participants with no more than 2 experiencing a dose-limiting toxicity (DLT). A DLT is defined as all treatment related Grade 3-5 adverse events (AEs) occurring from the initiation of moxetumomab pasudotox-tdfk therapy to within 30 days after the last dose of moxetumomab pasudotox-tdfk treatment assessed by the Common Terminology Criteria for Adverse Events (CTCAE v5.0). Grade 3 is severe, Grade 4 is life-threatening, and Grade 5 is death related to adverse event.
Measured: 4 weeks
Recommended Safe Dose of Rituximab/Ruxience
Recommended safe dose of rituximab/Ruxience is defined as the treatment of 10 participants with no more than 2 experiencing a dose-limiting toxicity (DLT). A DLT is defined as all treatment related Grade 3-5 adverse events (AEs) occurring from the initiation of moxetumomab pasudotox-tdfk therapy to within 30 days after the last dose of moxetumomab pasudotox-tdfk treatment assessed by the Common Terminology Criteria for Adverse Events (CTCAE v5.0). Grade 3 is severe, Grade 4 is life-threatening, and Grade 5 is death related to adverse event.
Measured: 4 weeks
Secondary outcomes (3)
Number of Participants Whose Cancer Shrinks or Disappears After Treatment
Number of participants whose cancer shrinks or disappears after treatment defined as minimal residual disease. MRD is no hairy cell leukemia (HCL) in the blood and bone marrow aspirate flow determined by immunohistochemistry (IHC) and flow cytometry of blood and bone marrow aspirate.
Measured: 28-42 days after day 1 of the last treatment.
Number of Participants Who Are Minimal Residual Disease (MRD)-Free
MRD-free is defined as participants with no hairy cell leukemia (HCL) in the blood and bone marrow aspirate flow determined by immunohistochemistry (IHC) and flow cytometry of blood and bone marrow aspirate.
Measured: 28-42 days after day 1 of the last treatment.
Duration of Response (DOR)
DOR is defined as the time of initial response until documented tumor progression. Response was assessed by the and is defined as an increase in symptoms or >25% decline in hematologic parameters related to disease, based on the judgement of the principal investigator. ≥50% increase in sum of products of perpendicular diameters of evaluable (> 2cm) lymphadenopathy or appearance of new evaluable lymph nodes > 2 cm short axis.
Measured: 28-42 days after day 1 of the last treatment.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted16 Jan 2019
- Study start3 Oct 2019
- Primary completion7 Jul 2023
- Study completion30 Jun 2029 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Other trials for Hairy Cell LeukemiaStudies of the same condition, open and under way.
- More trials run by National Cancer Institute (NCI)The sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 1
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Sequential
- Masking
- None (open label)
- Enrolment
- 18 participants (actual)
Sponsor and investigators
- Lead sponsor
- National Cancer Institute (NCI)
- Sponsor type
- US National Institutes of Health
- Responsible party
- Principal investigator, Robert Kreitman, M.D., National Cancer Institute (NCI)
- Investigators
- Robert J Kreitman, M.D., Principal investigator, National Cancer Institute (NCI)
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT03805932
- Sponsor's protocol ID
- 190042
- Other IDs
- 19-C-0042
- Status last verified
- Jun 2026
- First submitted
- 15 Jan 2019
- Last updated
- 29 Jun 2026
- Results posted
- Yes, on ClinicalTrials.gov
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- Yes: All individual participant data (IPD) recorded in the medical record will be shared with intramural investigators upon request.
Study at a glance
From the registry record, last updated by the sponsor on 29 Jun 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Phase I Study of Moxetumomab Pasudotox-tdfk (Lumoxiti (TM)) and Either Rituximab (Rituxan (R)) or Ruxience for Relapsed Hairy Cell Leukemia
- ClinicalTrials.gov ID
- NCT03805932
- Acronym / sponsor ID
- 190042
- Conditions
- Hairy Cell Leukemia
- Keywords
- HCL Variant, Recombinant Immunotoxin, Monoclonal Antibody, Targeted Therapy, Biologic Therapy
- Phase
- Phase 1
- Study type
- Interventional
- Recruitment status
- Active, not recruiting
- Enrolment
- 18 participants (actual)
- Lead sponsor
- National Cancer Institute (NCI)US National Institutes of Health
- Study start
- 3 Oct 2019 (actual)
- Primary completion
- 7 Jul 2023 (actual)
- Study completion
- 30 Jun 2029 (estimated)
- First posted
- 16 Jan 2019 (actual)
- Results
- Posted 28 Nov 2023
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Background:
Hairy cell leukemia (HCL) is a rare, slow-growing blood cancer in which the bone marrow makes too many of certain white blood cells. The antibody Rituximab/Ruxience binds to a protein in cancerous white blood cells and is often used to treat HCL. Researchers want to see if combining it with the drug Moxetumomab pasudotox-tdfk (also called Lumoxiti) can fight HCL better.
Objective:
To test the safety of Moxetumomab pasudotox taken with Rituximab/Ruxience for people with HCL or HCL variant.
Eligibility:
People age 18 years and older with HCL or HCL variant that has not responded to standard therapy
Design:
Participants will be screened with:
Medical history
Physical exam
Blood, heart, and urine tests
Test of blood oxygen levels
Review of bone marrow. This can be from previous test results or a new sample.
Scans
Exercise test
Participants will get the study drugs in up to 8 cycles. A cycle will last about 28 days.
The study drugs will be given through a plastic tube in a vein.
In the first week of cycle 1, participants will have:
1 visit to get Rituximab or Ruxience for 7.5 hours
3 visits to get Lumoxiti for 30 minutes per infusion
In the first week of cycles 2-8, participants will have:
- visit to get Rituximab/Ruxience for 2-4 hours and Lumoxiti for 30 minutes
- visits to get Lumoxiti for 30 minutes per infusion
Participants will be asked to drink lots of water and take aspirin during the cycles. They will get drugs to minimize allergic reactions.
Participants will repeat screening tests at visits throughout the cycles and 1 follow-up visit. They may have an eye exam.
...
Detailed description
Background:
- Hairy cell leukemia (HCL) is an indolent cluster of differentiation-22 (CD22+) B-cell leukemia comprising 2% of all leukemias, or approximately 1200 of the 62,130 new cases of leukemia/year in the United States (US). HCL variant (HCLv), also CD22+, is 10-20% as common as HCL, but more common in the relapsed/refractory population due to its poor prognosis and response to standard purine analog chemotherapy. hairy cell leukemia variant (HCL-V) cells are cluster of Differentiation 25 (CD25)-negative and wild type for BRAF, so HCLv patients are not candidates for BRAF inhibitors. CD25+ classic-appearing HCL-cells that express unmutated IGHV4-34 (Immunoglobulin Heavy Variable 4-34) are wild-type for BRAF, remain brightly CD22 positive, and confer a poor prognosis when treated with chemotherapy.
- Moxetumomab pasudotox-tdfk is a recombinant immunotoxin containing a variable domain (Fv) fragment of an anti-CD22 monoclonal antibody and truncated Pseudomonas exotoxin, which kills CD22+ cells by binding to CD22 via the (Fv) fragment, and induction of apoptotic cell death catalytic inhibition of protein synthesis in the cytosol.
- Moxetumomab pasudotox-tdfk in phase 1 testing demonstrated a high complete response (CR) rate in patients with chemoresistant HCL, without dose-limiting toxicity (DLT), but with reversible grade 2 hemolytic uremic syndrome (HUS) not requiring plasmapheresis.
- Moxetumomab pasudotox-tdfk completed multicenter phase 3 testing in 80 patients, meeting its complete response (CR) endpoint, with 8.8% incidence each of capillary leak syndrome (CLS, grade 3-4 2.5%), and HUS (grade 3-4 6.3%), both reversible.
- Moxetumomab pasudotox-tdfk is the only known non-chemotherapy-containing regimen for HCL which can consistently eradicate minimal residual disease (MRD), and this is associated with prolonged CR durations. Recently, US Food and Drug Administration (FDA) has accepted the Biologics License Application (BLA) for moxetumomab pasudotox-tdfk as the treatment of adult patients with HCL.
- Patients who did not achieve CR, or CR with MRD, often made neutralizing antibodies to the bacterial-based toxin, and/or had collections of HCL cells not completely eradicated by Moxetumomab pasudotox-tdfk. Both issues may be addressed by the addition of anti-cluster of differentiation 20 (CD20) monoclonal antibody (Mab) rituximab or Ruxience to Moxetumomab pasudotox-tdfk.
Objective:
-To determine the safety and toxicity of Moxetumomab pasudotox-tdfk and rituximab/Ruxience used at the planned dose level, in patients with HCL and HCLv.
Eligibility:
- HCL or HCLv with at least 1 prior purine analog, and, for HCL patients with >=2-years 1 month response, at least 1 other therapy.
- Need for treatment, either 1) absolute neutrophil count (ANC) <1/nL, 2) hemoglobin (Hgb) <10g/dL, 3) platelet (Plt) <100/nL, 4) symptomatic splenomegaly, or enlarging HCL mass > 2cm in short axis
- Serum creatinine < 1.5 mg/dL, or creatinine clearance greater than or equal to 60 mL/min by Cockcroft-Gault equation, where creatinine clearance = (140-age)(kg weight)/(72 x Creatinine).
- No uncontrolled infection or cardiopulmonary dysfunction
Design:
- Phase I trial, two arm, non-randomized, dose escalation
- Administration:
- Patients 1-13: Moxetumomab pasudotox-tdfk 30-40 mcg/kg intravenous (iv) over 30 min, Rituximab 375 mg/m^2 iv, 50-400 mg/hr.
- Patients 14-26: Moxetumomab pasudotox-tdfk 40 mcg/kg intravenous (iv) over 30 min, Ruxience 375 mg/m2 iv, 50-400 mg/hr
- Rituximab or Ruxience day 1 (begin day -2 on cycle 1), Moxetumomab pasudotox-tdfk days 1, 3, and 5.
- Patients will receive up to 4 cycles past documentation of CR without MRD, maximum 8.
- To prevent renal toxicity and hypovolemia, patients will be encouraged to drink water gradually, approximately 0.5-1 cup/hour or 6L/day, not going >3 hours without drinking from days 1 to 8 and to keep a hydration diary to record daily fluid consumption.
- To prevent rituximab/Ruxience toxicity, patients will receive prophylactic dexamethasone orally 0.5- 2 hours before the 1st dose of rituximab, and before subsequent doses until rituximab/Ruxience infusion reactions are not seen. Patients will also receive diphenhydramine, famotidine, and acetaminophen.
- Dexamethasone 4 mg orally (maximum 2 doses/day) will be given as needed to treat nausea or fever associated with Moxetumomab pasudotox-tdfk, which might prevent adequate water intake
- Statistical design:
- Up to 26 patients are intended to be treated in the trial. While a total of 26 evaluable patients will be enrolled, the accrual ceiling will be set at 30 to include screen failures and inevaluable patients.
Study design
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Sequential
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Moxetumomab - Dose Escalation 30 mcg/kg | Experimental | Drug: Moxetumomab Pasudotox-tdfk, Biological: Rituximab, Drug: Dexamethasone, Drug: Acetaminophen, Drug: Diphenhydramine, Drug: Famotidine, Drug: AspirinArm 1 Moxetumomab Pasudotox-tdfk + Rituximab |
| Moxetumomab - Dose Expansion 40 mcg/kg | Experimental | Drug: Moxetumomab Pasudotox-tdfk, Biological: Ruxience, Drug: Dexamethasone, Drug: Acetaminophen, Drug: Diphenhydramine, Drug: Famotidine, Drug: AspirinArm 1 and Arm 2 Moxetumomab Pasudotox-tdfk + Ruxience |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (18 listed)
- Diagnosis of hairy cell leukemia (HCL) or Hairy cell leukemia variant (HCLv).
- Treatment required for either 1) Absolute neutrophil count (ANC) <1/nL, 2) Hemoglobin <10g/dL, 3) Platelets<100/nL, 4) symptomatic splenomegaly, or 5) enlarging HCL mass > 2cm in short axis. Patients who have eligible blood counts within 4 weeks from the initiation of study will not be considered ineligible if subsequent blood counts prior to enrollment fluctuate and become ineligible up until the time of enrollment.
- Patients must be Pseudomonas-immunotoxin naive.
- HCL or HCLv with at least 1 prior purine analog, and, for HCL patients with >=2-years 1 month response, at least 1 other therapy. Age greater than or equal to 18 years as the disease under study, HCL/HCLv, has not been reported in children < age 18.
- Eastern Cooperative Oncology Group (ECOG) performance status less than or equal to2 (Karnofsky greater than or equal to 60%)
Key exclusion criteria (19 listed)
- Patients who have had chemotherapy, immunotherapy or radiotherapy within 4 weeks or treatment with rituximab/Ruxience within last 3 months prior to initiation of treatment.
- Patients who are receiving any other investigational agents.
- Breastfeeding within the projected duration of the study, starting with the screening visit through 6 months after the last dose of rituximab/Ruxience. Pregnant women are excluded from this study because moxetumomab pasudotox-tdfk and rituximab/Ruxience are agents with the potential for teratogenic or abortifacient effects. Because there is an unknown but potential risk for adverse events in nursing infants secondary to treatment of the mother with moxetumomab pasudotox-tdfk and rituximab/Ruxience, breastfeeding should be discontinued if the mother is treated with moxetumomab pasudotox-tdfk and rituximab/Ruxience.
- Patients with known brain metastases should be excluded from this clinical trial because of their poor prognosis and because they often develop progressive neurologic dysfunction that would confound the evaluation of neurologic and other adverse events.
- Uncontrolled intercurrent illness including, but not limited to, ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, uncontrolled hypertension, uncontrolled pulmonary infection, pulmonary edema or psychiatric illness/social situations that would limit compliance with study requirements.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Moxetumomab Pasudotox-tdfkAlso: LumoxitiMoxetumomab pasudotox-tdfk is administered at 30-40 ug/Kg intravenous (iv) over 30 min given on days 1, 3, 5 of each cycle. | Drug | Moxetumomab - Dose Escalation 30 mcg/kg, Moxetumomab - Dose Expansion 40 mcg/kg |
| RituximabAlso: RituxanRituximab will be administered at 375mg/m^2 intravenous (iv), 50-400 mg/hour (hr). On cycle 1, Rituximab is given on day -2, on subsequent cycles, Rituximab is given on day 1. | Biological | Moxetumomab - Dose Escalation 30 mcg/kg |
| RuxienceAlso: Rituximab-pvvrRuxience will be administered at 375mg/m^2 intravenous (iv), 50-400 mg/hour (hr). On cycle 1, Ruxience is given on day -2, on subsequent cycles, Ruxience is given on day 1 (Delta) | Biological | Moxetumomab - Dose Expansion 40 mcg/kg |
| DexamethasoneAlso: Ozurdex, Maxidex, DexPak 6 Day12 mg Cycle 1, Day -2; Cycles 2-8, Day 1. Administer 0.5-2 hours before rituximab/Ruxience. If participant has previous reaction to rituximab/Ruxience, give 12mg. If participants tolerate rituximab/Ruxience without problems, may hold at discretion of provider. Pre-medications are given prior to rituximab/Ruxience on day 1. | Drug | Moxetumomab - Dose Escalation 30 mcg/kg, Moxetumomab - Dose Expansion 40 mcg/kg |
| AcetaminophenAlso: Tylenol, Ofirmev, FeverAll650 mg Cycle 1, Day -2, Day 1, Day 3, Day 5. To be given 30-90 minutes prior to every moxetumomab pasudotox-tdfk infusion and recommended every 6 hours x 4 after the end of infusion; Cycles 2-8, Day 1, Day 3, Day 5. To be given 30-90 minutes prior to every moxetumomab pasudotox-tdfk infusion and recommended every 6 hours x 4 after the end of infusion. Pre-medications are given prior to rituximab/Ruxience on day 1. | Drug | Moxetumomab - Dose Escalation 30 mcg/kg, Moxetumomab - Dose Expansion 40 mcg/kg |
| DiphenhydramineAlso: Benadryl, Nytol, Banophen25-50 mg Cycle 1, Day -2; Cycles 2-8, Day 1. Pre-medications are given prior to rituximab/Ruxience on day 1. May be given prior to moxetumomab pasudotox-tdfk at discretion of principal investigator. | Drug | Moxetumomab - Dose Escalation 30 mcg/kg, Moxetumomab - Dose Expansion 40 mcg/kg |
| FamotidineAlso: Pepcid AC, Pepcid, Acid Controller20-40 mg Cycle 1, Day -2; Day 1, Day 3, Day 5. To be given 30-90 minutes prior to every moxetumomab pasudotox-tdfk infusion and is recommended every 12 hours x 2 after the end of infusion; Cycles 2-8, Day 1, Day 3, Day 5. To be given 30-90 minutes prior to every moxetumomab pasudotox-tdfk infusion and is recommended every 12 hours x 2 after the end of infusion. Pre-medications are given prior to rituximab/Ruxience on day 1. | Drug | Moxetumomab - Dose Escalation 30 mcg/kg, Moxetumomab - Dose Expansion 40 mcg/kg |
| AspirinAlso: Ecotrin, Enteric Coated Aspirin, Buffered Aspirin81 mg Cycle 1, Days 1-8; Cycles 2-8, Days 1-8. Only if platelet counts ≥ 100 x 109/L. | Drug | Moxetumomab - Dose Escalation 30 mcg/kg, Moxetumomab - Dose Expansion 40 mcg/kg |
Primary outcome
Recommended Safe Dose of Moxetumomab Pasudotox-tdfk
Time frame: 4 weeks
Recommended safe dose of moxetumomab pasudotox-tdfk is defined as the treatment of 10 participants with no more than 2 experiencing a dose-limiting toxicity (DLT). A DLT is defined as all treatment related Grade 3-5 adverse events (AEs) occurring from the initiation of moxetumomab pasudotox-tdfk therapy to within 30 days after the last dose of moxetumomab pasudotox-tdfk treatment assessed by the Common Terminology Criteria for Adverse Events (CTCAE v5.0). Grade 3 is severe, Grade 4 is life-threatening, and Grade 5 is death related to adverse event.
Recommended Safe Dose of Rituximab/Ruxience
Time frame: 4 weeks
Recommended safe dose of rituximab/Ruxience is defined as the treatment of 10 participants with no more than 2 experiencing a dose-limiting toxicity (DLT). A DLT is defined as all treatment related Grade 3-5 adverse events (AEs) occurring from the initiation of moxetumomab pasudotox-tdfk therapy to within 30 days after the last dose of moxetumomab pasudotox-tdfk treatment assessed by the Common Terminology Criteria for Adverse Events (CTCAE v5.0). Grade 3 is severe, Grade 4 is life-threatening, and Grade 5 is death related to adverse event.
3 secondary outcomes
Number of Participants Whose Cancer Shrinks or Disappears After Treatment
Time frame: 28-42 days after day 1 of the last treatment.
Number of Participants Who Are Minimal Residual Disease (MRD)-Free
Time frame: 28-42 days after day 1 of the last treatment.
Duration of Response (DOR)
Time frame: 28-42 days after day 1 of the last treatment.
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 29 Jun 2026.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- NIH Clinical Center Detailed Web PageLink provided by the sponsor.
- Individual participant dataSharing planned: Yes. All individual participant data (IPD) recorded in the medical record will be shared with intramural investigators upon request.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Robert J Kreitman, M.D. principal investigator
National Cancer Institute (NCI)
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 1 study testing Moxetumomab Pasudotox-tdfk, Rituximab and Ruxience in people with Hairy Cell Leukemia, run by National Cancer Institute (NCI) at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 18 inclusion and 19 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: under way, not looking for participants, as of the sponsor's last update on 29 Jun 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 1 studies test a treatment in a small group of people for the first time or in a new way, mainly to check safety and find the right dose.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
Yes. Results are posted in the registry (first posted 28 Nov 2023). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Recommended Safe Dose of Moxetumomab Pasudotox-tdfk (time frame: 4 weeks). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 29 Jun 2026.