Background:

The emergency of COVID-19, along with the current difficulties in responding to the high demand for vaccines, requests to the scientific community to find alternative treatments based on reuse of drugs as a strategy to prevent the progression of the disease in patients infected with SARS COV 2.

Objetive This study aims to evaluate the use of ivermectin in mild-stage patients to increase outpatient discharge and prevent the progression to moderate or severe stages of the disease.

Added value of this study We found that an intervention with ivermectin has impacted on the PPS in a population of outpatients care, between the 5th and 9th day. Also, the treatment increased the probability to obtain outpatient discharge, even in the presence of comorbidities.

Implications of all available evidence.

Research in Context According to the COVID-19 Treatment Guidelines by the NIH, most trials have several limitations. It needs results from adequately powered and well-designed clinical trials to provide evidence-based guidance on the role of ivermectin in the treatment of COVID- 19. However, our study shows overlaps in benefits with other authors, and taking together, these results are encouraging for further study about repurposing ivermectin for the treatment of COVID-19.

Technical Design:

Cluster Randomised Trials in outpatients care, n = 254. The subjects were divided into experimental (EG: n = 110) and control groups (CG: n = 144). The criteria for this choice were based on the geographical distribution of Health Services, locomotion, and logistics in current times of pandemic.

Sample Size:

Sample size was determined by the test comparing two proportions. It considered the following parameters to the bilateral test: n = 30,000 Total operating area population for services network to Primary Care; 95% confidence level, 3% precision, 5% proportion, n = 201 sample size without loss, 20% expected proportion of losses. The sample size calculated was n= 252 participants.

Participants:

The total group n = 254 enrolled outpatients care from the urban area-department heads and peri-urban area of the City San Miguel de Tucumán. The study was conducted between September 2020 to January 2021. The health coverage service was administered by the Health System of the State of Tucumán (SI.PRO.SA, Tucumán, Argentina). The people who agreed to participate in the study gave their informed consent before starting the study (Research Ethics Committee / Health Research Directorate, file number 054/2020).

Intervention Protocol:

The EG received protocol ivermectin orally 4 tablets of 6 mg = 24 mg every 7 days for 4 weeks plus symptomatic treatment (500mg paracetamol every 6 or 8h, no more than 4 tablets daily;100mg aspirin, 1 tablet per day with breakfast; 150mg Ranitidine, 1 tablet in the morning, and 1 tablet at night). The CG received only symptomatic treatment. Patients with comorbidities continued with the basic medication for the underlying pathology . All participants were evaluated by physical examination and COVID-19 infection was diagnosed with positive RT-PCR. Clinical evaluation of symptoms was carried throughout the study period. Enrolled subjects completed symptom questionnaires (including reporting of any adverse effects of treatment), physical examinations and remote clinical telemedicine follow-up and received outpatient discharge 4 weeks after the start of the intervention.

The 10-category ordinal scale recommended by the WHO was used to classify patients according to clinical patient state: ambulatory mild disease, moderate disease, severe disease.

Inclusion Criteria:

• Outpatients infected by SARSCoV-2 confirmed either by RT-PCR test, Neo Kit or rapid test authorized by ANMAT or by close contact or epidemiological link;
• Women of childbearing age with a negative pregnancy test;
• Mild disease-patients with two or more of the following symptoms: fever less than 38·5°C and higher than 37.5°C according to Ministry of Health, Argentina(16), isolated diarrheal episodes, hyposmia or hypogeusia, mild desaturation (between 96 and 93%), dyspnea, polyarthralgia, persistent headache, abdominal pain, erythema of the kidney, nonspecific rash.

Exclusion Criteria:

• Hypersensitivity or allergy to Ivermectin;
• Pregnant or lactating;
• Children or adolescents under 18 years of age;
• Patients with Neurological Pathology, Renal Insufficiency, Hepatic Insufficiency;
• Weight less than 40kg;
• Patients with concomitant use of drugs that act on GABA, barbiturate and benzodiazepine receptors;
• Patients who have not completed / signed the informed consent.

N/D

Each of the health centers (cluster of health centers) was randomly assigned to receive or not the intervention under study. The conglomerate of outpatients randomly assigned to the Experimental Group (EG) and Control Group (CG) belongs to the urban and peri-urban areas from Tucumán, and the selection of the centers was carried out considering a homogeneous socioeconomic profile in relation to the operating areas in which it is organized the Public Health Systems. Participants were recruited prior to cluster randomisation. Staff of each assistance center knew what intervention was being implemented as well as patients. Data processing group was blind to analyze the database.