*
https://www.thelancet.com/journals/lanrhe/article/PIIS2665-9..."They included 30 569 patients with systemic lupus erythematosus or rheumatoid arthritis who were already taking hydroxychloroquine in the 6 months before what was considered as the start of the pandemic in England and 164 068 patients with these rheumatic diseases who did not use hydroxychloroquine. The study found no significant difference in standardised cumulative COVID-19 mortality associated with hydroxychloroquine use (0·23% among hydroxychloroquine users and 0·22% among non-users) with an adjusted hazard ratio of 1·03 (95% CI 0·80–1·33)."
* https://www.acc.org/latest-in-cardiology/clinical-trials/202...
"Among patients exposed to patients with SARS-CoV-2, hydroxychloroquine, administered within a median duration of 2 days as post-exposure prophylaxis, did not reduce the incidence of SARS-CoV-2 or COVID-19 infection within 14 days, compared with placebo (vitamin C)."
* https://www.nih.gov/news-events/nih-research-matters/hydroxy...
"Researchers assessed each patient’s condition 14 days after being assigned to a treatment group. They used a seven-category scale ranging from one (death) to seven (discharged from the hospital and able to perform normal activities). The results showed no significant difference between the hydroxychloroquine and placebo groups. The scientists also found no differences in any of 12 additional outcomes, which included mortality 28 days after assignment to a treatment group or time to recovery. Based on the data, they concluded that hydroxychloroquine was not an effective treatment."
* https://jamanetwork.com/journals/jama/fullarticle/2772921
"Several published rigorous studies have demonstrated similar findings. In the well-conducted clinical trials published to date, hydroxychloroquine has been evaluated in a wide variety of populations, ranging from patients with severe illness2-4 to individuals at risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, in whom the drug was used as primary prophylaxis5; these studies failed to show any beneficial effect of the drug. This raises the question: How did medicine get to the point where so many studies were conducted assessing the possible benefit of hydroxychloroquine, that led to nearly identical findings, and have been published in major journals?"
* https://www.nejm.org/doi/full/10.1056/NEJMoa2022926
"Among patients hospitalized with Covid-19, those who received hydroxychloroquine did not have a lower incidence of death at 28 days than those who received usual care."
* https://www.cdc.gov/mmwr/volumes/69/wr/mm6935a4.htm
"New prescriptions by specialists who did not typically prescribe these medications (defined as specialties accounting for ≤2% of new prescriptions before 2020) increased from 1,143 prescriptions in February 2020 to 75,569 in March 2020, an 80-fold increase from March 2019."
* https://www.aljazeera.com/economy/2021/1/27/oklahoma-attempt...
"Oklahoma tries to return $2m worth of hydroxychloroquine"
Under what circumstances does it work?