MPH966 for Prevention of Graft-versus-host Disease After Allogeneic Hematopoietic Stem Cell Transplantation

Inclusion Criteria:

1. Provision of written informed consent prior to any study specific procedures
2. Plan to undergo allogeneic HCT for any cancer or non-cancer illness with a planned cell dose of ≥2 x 106 CD34/kg using peripheral blood stem cells.
3. Plan to receive a myeloablative conditioning regimen (see 4.3.1).
4. Plan to receive GVHD prophylaxis with tacrolimus and methotrexate.
5. Having a donor who is a 10 of 10 HLA match;
6. Karnofsky Performance Scale KPS ≥60
7. Willing to abstain from sexual activity or use two methods of birth control while on study drug and for 5 half-lives (4 days) after last dose.

Exclusion Criteria:

1. If female, pregnant or nursing.
2. Life expectancy \<6 months
3. Other malignancy or neoplastic disease (i.e. aside from the malignancy for which they are undergoing HCT) within the past 5 years with the exception of treated basal/squamous cell skin carcinoma or treated cervical cancer in situ
4. Clinically significant active infection within 1 week of starting study drug
5. Any of the following organ system function criteria:

   1. Cardiac: Ejection fraction ≤40% or myocardial infarction within 6 months of transplant or QTc \>450 msec for males and \>470 msec for females or other EKG abnormality which in the opinion of the investigator may put the subject at risk or interfere with study assessments
   2. Renal: Creatinine clearance (CLcr) ≤ 60 mL/min as estimated by the Cockcroft-Gault equation
   3. Pulmonary: FEV1, FVC, or corrected DLCO ≤40% predicted (forced expiratory volume in 1 second; forced vital capacity; and diffusing capacity of the lung for carbon monoxide, respectively)
   4. Hepatic: Total bilirubin \>1.5 x (in the absence of known inherited hyperbilirubinemia, e.g. Gilbert's) and/or aspartate transaminase (AST)/alanine transaminase (ALT) \>3 x upper limit of institutional normal for age (grade 2 or higher) and/or INR \>1.5 (unless on anticoagulant), or history or evidence of cirrhosis (e.g. esophageal varices, ascites, or hepatic encephalopathy) or other chronic liver disease (e.g. Wilson's disease, autoimmune liver disease, primary biliary cirrhosis, etc.). Abnormalities in platelet number or albumin will not be considered exclusion criteria given that these are often due to the hematologic malignancy for which the patient is undergoing HCT rather than actual liver dysfunction
   5. Uncontrolled infection, including detection of hepatitis B virus (HBV) or hepatitis C virus (HCV) by serology or nucleic acid testing or HIV by polymerase chain reaction (PCR)

   i. Treated HBV/HCV/HIV with documented clearance is ok f. Other significant organ dysfunction (cardiac, pulmonary, renal, metabolic or central nervous system) that is uncontrolled and may interfere with study completion
6. Any significant medial history of alcohol abuse within 3 months of starting study drug and/or unwillingness to abstain for the duration of the study and follow up periods
7. Prior (within 30 days) or concomitant use of another neutrophil elastase inhibitor (e.g. alpha-1 antitrypsin)
8. Plan for in vivo or ex vivo T cell depletion.
9. Participated in another clinical study involving an investigational drug or device within 30 days or 5 half-lives prior to planned start of MPH966/placebo, or scheduled to participate in another clinical study involving an investigational drug or device within Day 100 of transplant

   1. If the patient develops GVHD within the first 100 days, they are allowed to enroll on trials of investigational drugs to treat GVHD provided they come off of this study.
   2. Enrollment in biorepository or supportive care trials that do not involve investigational drugs or devices is allowed
10. Any clinically relevant abnormal findings in physical examination, vital signs, hematology, clinical chemistry, or urinalysis at visit, which in the opinion of the Investigator, may put the subject at risk because of his/her participation in the study, or may influence the results of the study, or the subject's ability to participate in the study
11. Low or intermediate risk acute leukemia in first complete remission, chronic myeloid leukemia in first chronic phase, and any benign (non-malignant) disorders (phase 1 dose-escalation portion only)