Hydroxychloroquine has been approved by FDA as one of the treatment options for COVID 19.Healthcare personnel are amongst those at highest risk to contract the disease. Several health authorities are now recommending the use of hydroxychloroquine as pre-exposure prophylaxis is in health care personnel. Several studies are on going in this context. However there is a controversy regarding the dosage regimen. This drug has a half life of 22.4 days. In this study we will be comparing three different doses of Hydroxychloroquine and additionally have a control group in order to determine the efficacy of hydroxychloroquine as pre- exposure prophylaxis in healthcare personnel in various doses.

Study design:

Phase 2 proof of concept study Study Type: Interventional (Clinical Trial) Estimated Enrollment : at least 200 participants Since the investigators have no current data on pre-exposure prophylaxis to calculate sample size statistically, so a minimum of 50 participants in each arm will be recruited including 20% attrition rate. The investigators will be recruiting a minimum of 200 participants in the study , that is at least 50 in each of the four arms.

Allocation: Randomized Intervention Model: Parallel Assignment Study model: Parallel group interventional study Location: SZABMU/PIMS Study duration: a minimum of 12 weeks from recruitment

Materials and Methods:

Participants will be recruited after approval from Ethical Review Board .A written informed consent will be taken from all participants. Participants fulfilling the eligibility criteria will be randomized to 4 arms.

Arm Intervention /treatment

Experimental group 1: Hydroxychloroquine 400 mg twice a day 1,followed by 400 mg weekly for a total of 12 weeks Drug: Hydroxychloroquin HCQ 200 mg, oral

Experimental group 2:Hydroxychloroquine 400 mg on day 1 followed by 400mg once every 3 weeks for a total of 12 weeks Drug: Hydroxychloroquin HCQ 200 mg, oral

Experimental group 3:Hydroxychloroquine 200 mg on day 1 followed by 200 mg once every 3 weeks for a total of 12 weeks Drug: Hydroxychloroquin HCQ 200 mg, oral

Control Group : Placebo 200mg will be given on day 1 followed by Placebo 200mg every three weeks for a total of 12 weeks.

Base line characteristics of all participants will be recorded including age ,gender,role of healthcare personnel, comorbidities, and drugs the participant is using.

Samples will be collected for complete picture blood, liver and renal function tests and electrocardiogram. These tests will also be conducted every month till the end of the trial and the participants will be monitored for any adverse effects.

During the study duration all participants will self- report any symptoms related to COVID 19 and any adverse reactions from the drug. Participants having COVID 19 symptoms at any time will be tested by the gold standard test PCR for SARS-COV-2 using nasopharyngeal and oropharyngeal swabs.

All participants at the end of the study will have PCR for SARS-COV-2 and if available IgM and IgG serology to find out if they had any infection, did not get infected at all or only had asymptomatic or mild infection.

Inclusion Criteria after taking a written informed consent:

• A healthcare worker at high risk for COVID19 exposure (defined below):

  • Persons primarily working in emergency departments (physicians, nurses, ancillary staff, triage personnel) ;
  • Persons primarily working in intensive care units (physicians, nurses, ancillary staff, respiratory therapists) ;
  • Persons performing aerosol generating procedures (i.e. anesthesiologists, nurse anesthetists, gastroenterologists performing endoscopy, Pulmonologists performing bronchoscopy);
  • First responders (i.e. EMTs, paramedics) ;
  • Persons working in the departments of General Medicine, Pulmonology, Infectious disease and Isolation wards.

Exclusion Criteria:

• Active COVID-19 disease;
• Confirmed prior COVID-19 disease;
• Current fever, cough, shortness of breath;
• Contraindication or hypersensitivity to chloroquine or hydroxychloroquine ad hypersensitivity to 4-aminoquinoline compounds;
• Pregnancy;
• Lactation;
• Prior retinal eye disease;
• Known Chronic Kidney disease, Stage 4 or 5 or dialysis;
• Known glucose-6 phosphate dehydrogenase (G-6-PD) deficiency ;
• Weight <40 kg;
• Current use of chloroquine,hydroxychloroquine or cardiac medicines like flecainide, amiodarone, digoxin, procainamide, or propafenone;
• Current use of medications with known significant drug-drug interactions: artemether, lumefantrine, mefloquine, tamoxifen or methotrexate;
• Current use of medications causing QT interval prolongation like: macrolides,antipsychotics,quinolones,antihistamines,SSRIs,tricyclic antidepressants, antifungals;
• Recent Myocardial Infarction;
• History of Epilepsy