Combination Therapy for Cancer Related Fatigue in Patients With Metastatic Cancers

Primary Objectives: 1\. To determine if the combination therapy of PI with OLP (combination therapy group) is superior to PI alone group in the treatment of cancer-related fatigue (CRF) as measured by the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F) scale. We hypothesize that the combination of OLP+PI in these patients will result in a greater reduction of CRF compared to PI alone. Secondary Objectives: 1\. To determine if Combination Therapy group is superior to PI Only group for the treatment of CRF at 3 months and 6 months after treatment. We hypothesize that the combination of OLP+PI in these patients will result in a greater reduction of CRF after 3 months and 6 months after treatment 3\. To determine the effects of combination therapy on fatigue-related quality-of-life, mood, sleep-wake activity, cognitive measures, and inflammation. We will assess measures including quality of life (Functional Assessment of Cancer Therapy - General, FACT- G), multidimensional fatigue (Multidimensional Fatigue Symptom Inventory, MFSI-SF), sleep disturbance (PROMIS-sleep), anxiety (Hospital Anxiety and Depression Scale - HADS), depressed mood (HADS), cognitive function (Symbol digit modality test, SDMT), sleep/wake time activity (actigraphy), and inflammation (C-reactive protein levels). We hypothesize that combination therapy will result in improvements in CRF-related quality of life, mood, sleep-wake activity, and cognitive measures.