Low dose hydroxychloroquine prophylaxis for COVID-19 - a prospective study

RE-HCP2 study group,; Panda, P. K.

Background: Since the outbreak of COVID-19 pandemic, the world began a frantic search for possible prophylactic options. While trials on hydroxychloroquine (HCQ) prophylaxis are ongoing, concrete evidence is lacking. The study aimed to determine the relative efficacy of various doses of oral HCQ in prophylaxis and mitigating the severity of COVID-19 in healthcare workers. Methods: This was a prospective cohort with four arms (high, medium, low dose, and control) of HCQ prophylaxis, used by healthcare workers at a tertiary care center in India. Participants were grouped as per their opting for any one arm on a voluntary basis as per institute policy under the Government guidance. The outcomes studied were COVID-19 positivity by RT-PCR and its severity assessed by WHO COVID-19 severity scale. Results: Total 486 participants were enrolled, of which 29 (6%) opted for low dose, 2 (<1%) medium dose, and none for high dose HCQ while 455 (93.6%) were in the control arm. Of the 164 participants who underwent RT-PCR, 96 (58.2%) tested positive. Out of these 96 positive cases, the majority of them (79 of 96 [82.3%]) were ambulatory and were managed conservatively at home. Only 17.7% (17 of 96) participants, all of them from the control group, required hospitalization with the mild-moderate disease. None of the participants had severe disease, COVID-related complications, ICU stay, or death. The difference in the outcome assessed amongst the various arms was statistically insignificant (p value >0.05). Conclusion: This single-center study demonstrated that HCQ prophylaxis in healthcare workers does not cause a significant reduction in COVID-19 as well as mitigating its severity in those infected. At present, most of the trials have not shown any benefit. The debate continues to rage, should HCQ prophylaxis be given to healthcare workers for chemoprophylaxis?