Inclusion Criteria:

          -  1. Histologic diagnosis of unresectable or metastatic melanoma. For unknown primary
             disease, diagnosis of metastatic disease by cytology FNA is not acceptable. BRAF
             wild-type confirmed, and NRAS mutation assessed.

             2. Age > 18 years.

             3. Any number of prior systemic therapeutic regimens for unresectable stage III or
             stage IV melanoma. This includes chemotherapy, immunotherapy, pathway inhibitors,
             biochemotherapy, or investigational treatments. Patients may also have received
             therapies in the adjuvant setting.

             4. ECOG Performance status 0-2.

             5. Adequate organ and marrow function as defined below:

          -  leukocytes ≥ 2,000/mcL

          -  absolute neutrophil count ≥ 1,000/mcL

          -  platelets ≥ 75,000/mcl

          -  total bilirubin < 3 x institutional upper limit of normal

          -  AST(SGOT)/ALT(SPGT) ≤ 2.5 X institutional upper limit of normal

          -  creatinine < 1.5 mg/dL

          -  cardiac ejection fraction > 50%

          -  QTc < 480msec

             6. 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, for
             the duration of study participation, and for 90 days following completion of therapy.
             Should a woman become pregnant or suspect she is pregnant while participating in this
             study, she should inform her treating physician immediately. A female of child-bearing
             potential is any woman (regardless of sexual orientation, having undergone a tubal
             ligation, or remaining celibate by choice) who meets the following criteria: Has not
             undergone a hysterectomy or bilateral oophorectomy; or Has not been naturally
             postmenopausal for at least 12 consecutive months (i.e., has had menses at any time in
             the preceding 12 consecutive months).

             7. All sites of disease must be evaluated within 4 weeks prior to beginning therapy.
             Patients must have measurable disease as defined by RECIST v1.1.

             8. Ability to understand and the willingness to sign a written informed consent.

             9. Patients must be willing to undergo tumor biopsy pretreatment and at relapse.

        Exclusion Criteria:

          1. Subjects who have had chemotherapy or radiotherapy or any systemic therapy for
             melanoma within 2 weeks prior to entering the study or those who have not recovered
             from adverse events due to agents administered more than 2 weeks earlier. No
             concomitant therapy is allowed including IL2, interferon, ipilimumab, anti-PD-1 or
             anti-PD-L1 antibody, cytotoxic chemotherapy, immunosuppressive agents, or other
             investigational therapies.

          2. Active infection with hepatitis B or C or HIV.

          3. Subjects with active CNS disease are excluded. Patient with brain metastases
             previously treated with surgery or radiation therapy and with confirmed SD for >4
             weeks are allowed.

          4. Patients are excluded if they have a history of any other malignancy from which the
             patient has been disease-free for less than 2 years, with the exception of adequately
             treated and cured basal or squamous cell skin cancer, superficial bladder cancer or
             carcinoma in situ of the cervix.

          5. Uncontrolled inter-current illness including, but not limited to, ongoing or active
             infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac
             arrhythmia, or psychiatric illness/social situations that would limit compliance with
             study requirements. Cardiac symptoms or events within 24 weeks.

          6. History of predisposition to retinal vein occlusion or central serous retinopathy.

          7. Inability to assess BRAF or NRAS mutation status. Hypersensitivity to digoxin.

          8. Wolff-Parkinson White syndrome or AV block or sinus node dysfunction.