Hydroxychloroquine: Pharmacological, physicochemical aspects and activity enhancement through experimental formulations

Hydroxychloroquine is a drug developed to combat the main etiological agent of Malaria, Plasmodium falciparum, with is currently extended to the treatment of Systemic Lupus Erythematosus and Rheumatoid Arthritis. Despite its lesser use as an anti-malarian agent nowadays, the drug has gained recent prominence in the media and in experimental studies due to its possible action against Sars-CoV-2, although it was proved worthless against Covid-19. Tissue accumulation and retinopathy are characteristic adverse effects in the long term and in highdose regimens. So, to reduce these effects, to direct its release or bypass the plasmodium resistance to hydroxychloroquine, experimental formulations are under way. Therefore, this work aim is to compile and discuss those formulations described in pharmacotechnical publications, bringing pharmacological and physicochemical of the molecule as a theoretical basis for the discussion. Most studies carried out in vitro experiments and clinical tests were performed only in cases of autoimmune diseases and COVID-19. Among the experimental formulations, there were varied presentations, including nanoparticles, intravaginal rings, transdermal patches, as well as therapeutic targets. The panorama presented here may contribute to new studies of formulations that aim to optimize the application of hydroxychloroquine for treatments of pathologies in which its effectiveness has been demonstrated.