Ruxolitinib Phosphate in Treating Patients With Chronic Neutrophilic Leukemia or Atypical Chronic Myeloid Leukemia

Inclusion Criteria:

   - Subjects must be newly diagnosed or previously diagnosed with CNL or aCML; all
   patients must have a bone marrow biopsy completed during the screening or baseline
   period if one has not been done within 90 days of day 1, cycle one

   - Subjects must have platelet count greater than 25,000 per microliter at baseline and
   at the start of study (day 1, cycle 1) visit

   - Subjects must be able to discontinue any drug treatment aimed at lowering disease
   burden in CNL or aCML; subjects should discontinue hydroxyurea to treat underlying CNL
   or aCML disease no later than day -7 (one week before starting ruxolitinib); for drugs
   that have more long-lasting effects on the marrow, such as thalidomide and its
   analogs, and interferon, subjects should discontinue these no later than day -28

   - Subjects must be willing to accept/continue transfusions to treat low hemoglobin
   levels

   - Subjects must have a life expectancy of > 6 months

Exclusion Criteria:

   - Subjects unable to review and sign informed consent form

   - Females who are pregnant or breastfeeding, and males and females who cannot comply
   with requirements to avoid fathering a child or becoming pregnant

   - Subjects with known diagnosis of human immunodeficiency virus (HIV) or chronic active
   Hepatitis B or C; viral testing is not required; subjects with a history of Hepatitis
   B and/or C are allowed on trial if the virus is undetected at the time of enrollment

   - Subjects with inadequate liver (alanine aminotransferase [ALT]/serum glutamate
   pyruvate transaminase [SGPT] above 4 X upper limit of normal [ULN] or direct bilirubin
   4 X ULN AND the lab abnormalities are felt to be due to underlying liver dysfunction)

   - Subjects with end stage renal function (creatinine clearance [CrCl] < 15 mL/min or
   glomerular filtration rate [GFR] <15 mL/min) regardless of whether hemodialysis is
   required

   - Subjects with clinically serious infections requiring ongoing antibiotic therapy

   - Subjects with severe (immediately life threatening) and recent (occurring within the
   last 3 months) cardiac dysfunction, pulmonary dysfunction, esophageal variceal
   bleeding, hemorrhagic strokes, or intracranial hemorrhage are not eligible for study
   participation

   - Subjects requiring therapeutic doses of anticoagulation or anti-platelet therapies
   (aspirin above 81 mg daily, Plavix or similar agents) AND platelet counts are below
   50,000 on two different laboratory evaluations, separated by minimum of two weeks

   - Taking investigational or commercial agents or therapies with the intent to treat the
   subject's malignancy other than those therapies permitted

   - Subjects with invasive malignancy over the previous 2 years except treated early stage
   carcinomas of the skin, completely resected intraepithelial carcinoma of the cervix,
   and completely resected papillary thyroid and follicular thyroid cancers

   - Previous allergic reactions to janus kinase (JAK) inhibitors or excipients

   - Prior therapy with ruxolitinib or other JAK inhibitors

   - Subjects who have had major surgery within 4 weeks prior to entering the study

   - Subjects who are anticipated to receive a transplant within the first 6 months of
   treatment on trial