Moxetumomab Pasudotox for Advanced Hairy Cell Leukemia

• INCLUSION CRITERIA:
• Patients must have histologically confirmed hairy cell leukemia or hairy cell leukemia variant .with a need for therapy based on at least one of the following criteria:

neutrophils less than 1000/mm(3)

platelets less than 100,000/mm(3)

hemoglobin less than 10 g/dL)

symptomatic splenomegaly.

• Patients must be Pseudomonas-immunotoxin na(SqrRoot) ve
• Patients must have had at least 2 prior purine analogs, or at least 1 course of purine analog and 1 of either rituximub or BRAF inhibitor.
• Men or women age greater than or equal to 18 years. Because this disease does not generally occur in children, children are excluded from this study, but will be eligible for future pediatric trials in other indications.
• ECOG performance status less than or equal to 2.
• The effects of moxetumomab pasudotox on the developing human fetus are unknown. For this reason, women of child-bearing potential and men must agree to use adequate contraception (hormonal or barrier method of birth control; abstinence) prior to study entry and for the duration of study participation, and 4 months after completion of moxetumomab pasudotox administration. 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.
• Patients must have adequate organ function as defined below:
• total bilirubin less than or equal to 1.5 mg/dL, unless consistent with Gilbert s (ratio between total and direct bilirubin greater than 5)
• AST and ALT less than or equal to 3 times upper limit of normal (ULN)
• alkaline phosphatase less than or equal to 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 as estimated by the Cockcroft-Gault equation
• Prothrombin time/INR or partial thromboplastin time less 2.5 ULN, fibrinogen greater than or equal to 0.5 LLN; if on warfarin, INR less than 3.5, if on any other anticoagulation, PT less than 2.5 times baseline
• Ability to understand and the willingness to sign a written informed consent document.
• Life expectancy greater than or equal to 6 months

EXCLUSION CRITERIA

• Patients who have had chemotherapy, immunotherapy or radiotherapy within 4 weeks prior to entering the study.
• Patients who are receiving any other investigational agents.
• 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.
• Patients with clinically significant ophthalmologic findings during screening
• Pregnant or breastfeeding females. The effects of moxetumomab pasudotox on the developing fetus are unknown. Because there is an unknown but potential risk for adverse events in nursing infants secondary to treatment of the mother with moxetumomab pasudotox breastfeeding should be discontinued if the mother is treated with moxetumomab pasudotox
• Positive for Hepatitis B surface antigen unless the patient is on Lamivudine or Entecavir and Hepatitis B Viral DNA load is less than 2000 IU/mL.
• Lymph nodes greater than 4cm or prior splenectomy
• Active second malignancy requiring treatment other than minor resection of indolent cancers like basal cell and squamous skin cancers
• Uncontrolled intercurrent illness including, but not limited to, ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, malaria infection or psychiatric illness/social situations that would limit compliance with study requirements.
• HIV-positive patients unless taking appropriate anti-HIV medications with a CD4 count of greater than 200. Otherwise, there may be increased risk of lethal infections when temporarily suppressing normal B-cells.
• History of allogeneic bone marrow transplant.
• Patients with history of both thromboembolism and known congenital hypercoagulable conditions.
• Uncontrolled pulmonary infection, pulmonary edema.
• Oxygen saturation at rest less than 88% measured by pulse oximetry or PaO (2) less than or equal to 55 mm Hg.
• Serum albumin less than 2 g/dL.
• Radioimmunotherapy within 2 years prior to enrollment in study.
• ANC less than 1000/mm(3), or platelet count less than 50,000/mm(3), if these cytopenias are not judged by the investigator to be due to underlying disease (ie, potentially reversible with antineoplastic therapy). A patient will not be excluded because of pancytopenia greater than or equal to Grade 3, or erythropoietin dependence, if it is due to disease, based on the results of bone marrow studies.
• Patients with less than 50% of predicted forced expiratory volume (FEV1) or less than 50% of predicted diffusing capacity for carbon monoxide (DLCO), corrected for hemoglobin concentration and alveolar volume. Note: Patients with no prior history of pulmonary illness are not required to have PFTs. FEV1 will be assessed after bronchodilator therapy.
• Patients with history of thrombotic microangiopathy or TTP-HUS.
• Patients with QTc elevation > grade 1
• Patient on high dose estrogen (defined as > 0.625 mg/day of an estrogen compound.
• Patients with clinical evidence of disseminated intravascular coagulation (grade 3-4)