This study was designed to evaluate the potential of ivermectin as a repositionable drug, for the treatment of mild cases of COVID-19. Ivermectin has shown an effect on clinical manifestations of COVID-19, including a decrease in the percentage of symptoms reported in the medical examination and an increase in the chance for medical release in EG.
Currently, many studies about ivermectin and its potential against SARS-CoV-2 are complete or in development. A pilot study that evaluates the effect of early treatment with ivermectin for COVID-19, sheds some light on the potential of ivermectin in a tendency to lower viral loads and lower IgG titers(23). Other work, either from Argentina shows a faster viral clearance in treated participants(13). Chaccour et al. reported that patients treated with ivermectin experienced a significant diminution of 50% anosmia/ hyposmia than those in the placebo group (76 vs. 158 patient-days of anosmia/hyposmia)(23). The ivermectin group also reported 30% fewer coughs (68 vs. 97 patient-days of cough). However, in this study, there were no major differences between ivermectin and placebo in the reported patient days of fever, general malaise, headache, or nasal congestion(23).
In line with these results, in our study, outpatients report a significant drop in the percentage of upper airway symptoms in COVID-19 (taste and/or smell disturbance, odynophagia, cough), see Table 2. Concomitantly, the results reported here show that the use of ivermectin produces a decrease in the number of symptoms reported by patients, such as fever and diarrhea, but above all, a significant decrease in taste and smell loss, which is related to the effects of viral load on upper air vials in patients with mild COVID-19. No patient from either group progressed to severe disease.
Recently, Lopez Medina et al. published a study of ivermectin concerning the time resolution of symptoms in mild patients(24). Although they do not recommend the use of ivermectin as a treatment for COVID-19, there are some similarities (and differences) with the results of the present study. We agree that there are no significant differences between both groups at 14 days (see Fig. 2), but our main finding shows that the effect of treatment is observed between 5 and 8 days after the patient starts treatment. This difference may be due to the administration of the dose, which in our case is weekly and not daily. The clinical follow-up of the patients was carried out in person in the Primary Health Centers, which is more accurate concerning symptom recording.
There are results that provide evidence of the potential benefit of early intervention with ivermectin for the treatment of patients diagnosed with mild stages of COVID-19, as Elgazzar et al. trial(14). Many studies present the potential of ivermectin for a viral load reduction, as has been suggested by Caly et al. in vitro. This could have the potential effect on disease progression and spread. (13, 14, 23, 25)
A single-center prospective clinical trial performed in 167 patients with mild to severe COVID-19 from Argentina, found that none of the mild or moderate cases of COVID-19 who received the experimental treatment with ivermectin were hospitalized, and only one patient died (0.59%)(26). In México a comparative effectiveness study was performed among patients with laboratory-confirmed SARS-CoV-2 infection. The experimental group received a TNR4. TNR4 consists of four drugs administered orally to COVID-19 cases with mild or moderate symptoms: (1) ivermectin, 12 MG single dose; (2) azithromycin 500 mg for 4 days; (3) montelukast, 60 mg on the first day and then 10 mg between days 2 to 21; and (4) acetylsalicylic acid, 100 mg for 30 days. This study indicated that the TNR4 significantly increases the likelihood of full recovery within 14 days after the onset of symptoms, and decreases the risk of hospitalization or death among ambulatory cases of COVID-19. (27)
The addition of ivermectin to standard care can be effective for the treatment of COVID-19 patients with significant reductions in mortality and duration hospital stay compared to Hydroxychloroquine plus standard treatment(14). Early use of ivermectin is very useful for controlling COVID-19 infections, improving cytokines storm and prophylaxis of frontline health care as well as household contacts(14).
Our study has sizable limitations. The absence of a placebo group is due to the lack of funding from a sponsor and the need to guarantee treatment to the entire population. The sample size, although representative, is too small to obtain conclusive results. It’s a descriptive study of clinical follow-up at 28 days without report of adverse events which it would be beneficial to evaluate in future works. Or study demonstrates similar benefits with other studies, and taken together, these results are encouraging for further study about repurposing ivermectin for the treatment of COVID-19, considering that it is an inexpensive drug and is accessible in the local pharmaceutical industry (Argentina). We suggest new clinical intervention studies in our region and other countries that may show the effect of the IVER compound in mild-stage outpatients.