A Study Examining the Medication Apremilast as Treatment for Chronic Itch

Inclusion Criteria: Key Inclusion Criteria: A subject who meets all of the following criteria may be included in the study: * Male and non-pregnant, non-lactating female subjects aged 18 years or older * Diagnosed with chronic idiopathic pruritus (CIP) with an NRS Itch Score of ≥ 7 at both Screening and Baseline * Diagnosis of CIP for at least 6 weeks prior to screening * Willingness to avoid pregnancy or fathering of children * Ability and willingness to provide written informed consent * Willing and able to comply with all study requirements and restrictions * Willing to not participate in any other interventional trial for the duration of their participation * Subjects must be in good health as determined by medical history, physical examination, electrocardiogram, clinical laboratory tests and vital signs * Failure of a course 2-week course of treatment with topical triamcinolone 0.1% ointment BID * Histopathological demonstration of skin eosinophils, mast cell activation, lymphocytic infiltration, and/or dermal edema Exclusion Criteria: Key Exclusion Criteria: A subject who meets any of the following criteria will be excluded from the study: * Chronic pruritus due to a defined primary dermatologic disorder (e.g., atopic dermatitis, psoriasis, etc.) * Patients with a prior diagnosis of excoriation disorder * Use of topical treatments for CIP (other than bland emollients) within 1 week of Baseline * Systemic immunosuppressive or immunomodulating drugs within 4 weeks of Baseline * Subjects with cytopenias at screening, defined as: * Leukocytes \< 3 × 109/L. * Neutrophils \< lower limit of normal. * Lymphocytes \< 0.5 × 109/L * Hemoglobin \< 10 g/dL. * Platelets \< 100 × 109/L. * Unwilling or unable to follow medication restrictions described in Section 5.6.3, or unwilling or unable to sufficiently washout from use of restricted medication * Under medical treatment for a skin disease with a therapy listed in the prohibited medications section that may influence the results of the study * Current clinically significant cardiovascular, respiratory, neurologic, hepatic, hematopoietic, renal gastrointestinal, endocrine or metabolic dysfunction unless currently controlled and stable, including (but not limited to) the following: Positive for Hepatitis C antibody test (anti-HCF) Positive for hepatitis B surface antigen (HBsAg) or hepatitis B core antibody (HBcAb) Positive for HIV (DUO test, p24 antigen) * Active malignancy * Active substance abuse or history of substance abuse within 6 months of screening * History (including family history) or current evidence of congenital long QT syndrome or known acquired QT prolongation * Exposure to any investigational medication, including placebo, within 60 days of the Baseline Visit * Subjects who had previously received apremilast * Subjects with severely impaired liver function (Child-Pugh Class C) or end-stage renal disease on dialysis or at least 1 of the following: * Serum creatinine \> 1.5 mg/dL * Alanine aminotransferase or aspartate aminotransferase ≥ 1.5 × upper limit of normal * Anyone affiliated with the site or sponsor and/or anyone who may consent under duress * Any other sound medical reason as determined by the Investigator including any condition which may lead to an unfavorable risk-benefit of study participation, may interfere with study compliance or may confound results.