Hydroxychloroquine in Previously Treated Patients With Metastatic Pancreatic Cancer

Inclusion Criteria: * Histologically confirmed unresectable pancreatic adenocarcinoma that is metastatic to distant sites * Measurable disease, defined as at least one lesion that can accurately be measured in at least one dimension * Patients must have been treated with one or two previous lines of chemotherapy for metastatic disease with documented tumor progression or intolerance due to toxicity * Minimum of two weeks since any major surgery, completion of radiation, or completion of all prior systemic anticancer therapy * 18 years of age or older * Life expectancy of greater than 12 weeks * ECOG performance status of 0, 1 or 2 * Normal organ and marrow function as outlined in the protocol * Patients must be able to swallow pills * Women of child-bearing potential and men must agree to use adequate contraception prior to study entry and for the duration of study participation. Exclusion Criteria: * Participants who have had chemotherapy or radiotherapy within 2 weeks prior to entering the study or those who have not recovered from adverse events due to agents administered more than 4 weeks earlier. * More than two previous chemotherapy regimens for the treatment of metastatic pancreatic cancer * Uncontrolled brain or leptomeningeal metastases * History of macular degeneration, visual field changes, retinal disease, or cataracts that would interfere with funduscopic eye examinations * History of allergic reactions attributed to compounds of similar chemical or biologic composition to hydroxychloroquine * Previous treatment with chloroquine or hydroxychloroquine for other indications, such as rheumatoid arthritis, SLE or malaria prophylaxis * Prior treatment with any investigational drug within the preceding 4 weeks * Impairment of gastrointestinal function or gastrointestinal disease that may significantly alter absorption of hydroxychloroquine. Patients who have undergone a Whipple procedure for localized pancreatic cancer are not excluded from enrollment * History of non-compliance to medical regimens * Known diagnosis of glucose-6-phosphate deficiency, porphyria or psoriasis * Penicillamine use for Wilson's disease or any other indication * Uncontrolled intercurrent 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 * Pregnant or breastfeeding women * Individuals with a history of a different malignancy are ineligible except for the following circumstances. Individuals with a history of other malignancies are eligible if they have been disease-free for at least 3-years and are deemed by the investigator to be at low risk for recurrence of that malignancy. Individuals with the following cancers are eligible if diagnosed and treated within the past three years: cervical cancer in situ, and basal cell or squamous cell carcinoma * HIV-positive individuals on combination antiretroviral therapy