IRCT20200405046958N1 IRCT 2020-04-14 Mashhad University of Medical Sciences Prevention of Novel Coronavirus Disease by Hydroxychloroquine in cancer patients. Effect of Hydroxychloroquine on Novel Coronavirus Disease (COVID-19) prevention in cancer patients under treatment 2020-04-13 anticipated 60 Complete https://irct.ir/trial/46946 interventional Randomization: Randomized, Blinding: Triple blinded, Placebo: Used, Assignment: Parallel, Purpose: Prevention, Randomization description: Randomization will be performed using randomly permuted blocks. By using online website (www.randomization.com) the randomization sequence will be produced by quadruple blocks, Blinding description: The patient and the physician do not know whether the patient is in the intervention or the control group. The data analyser will also be blinded regarding the intervention and control groups. 2-3 Condition 1: COVID-19 disease. Condition 2: Acute myeloid leukemia. Condition 3: Acute lymphoblastic leukemia. Condition 4: Breast cancer. Condition 5: Colon cancer. Condition 6: Diffuse large B cell lymphoma. Intervention 1: Intervention arm: Patients in this group receive 200 mg of hydroxychloroquine tablets (manufactured by Amin Pharmaceutical Company, Isfahan) every other day for 2 months. At the same time, specific cancer treatments are given. Intervention 2: Control arm: Patients receive the placebo, which is similar to Amin's hydroxychloroquine tablets, one every other day. Cancer treatment of these patients is done according to the standard during this period. Undecided - It is not yet known if there will be a plan to make this available Justification or reason for indecision in sharing IPD is Approval should be obtained from the Research Ethics Committee of Mashhad University of Medical Sciences to access patients' data about COVID-19.