What can visual caregivers expect with patients treated for SARS-CoV-2? An analysis of ongoing clinical trials and ocular side effects

Within the COVID-19 pandemic context, the WHO has proposed a list of medicines to treat patients with severe acute respiratory syndrome (SARS-CoV-2). An analysis of their ocular side effects was performed. Only chloroquine and hydroxychloroquine were found to have an ocular impact in the medium and long-term. Detailed search strategies were performed in EMBASE, MEDLINE, SCOPUS and WOS Core Collection. Additionally, the worldwide ongoing clinical trials including chloroquine or hydroxychloroquine were evaluated, and their proposals of drug administration and exclusion criteria analyzed. In general, high maximum cumulative doses of chloroquine or hydroxychloroquine are being used for a short period in 135 currently underway clinical trials (to 21st April 2020). Typically, the doses were 2 to 5 times greater than the AAO recommendation (adjusted to weight) to avoid toxic retinopathy, the most undesirable ocular side effect. Maximum cumulative doses up to 12,000 mg for chloroquine and 18,000 mg for hydroxychloroquine were found. In prophylaxis clinical trials, 72,000 mg and 22,500 mg were the maximum cumulative doses for hydroxychloroquine and chloroquine respectively. Only 48% of the clinical trials considered retinal impairment as an exclusion criterion, and just one referred to an ophthalmic examination previous to study inclusion. How chloroquine and hydroxychloroquine treatment affect patients with a previous retinal condition is still poorly understood. A comprehensive ophthalmological examination 6 months after treatment is recommended in this subgroup. This review provides an overview of this topic and sheds light on the challenges visual caregivers may face regarding these repurposed drugs.