Atovaquone

Atovaquone, sold under the brand name Mepron, is a quinone antimicrobial medication for the prevention and treatment of "Pneumocystis jirovecii" pneumonia (PCP).
Atovaquone is a chemical compound that belongs to the class of naphthoquinones. Atovaquone is a hydroxy-1,4-naphthoquinone, an analog of ubiquinone, with antipneumocystic activity.
Medical uses.
Atovaquone is a medication used to treat or prevent:
Trimethoprim/sulfamethoxazole (TMP-SMX, Bactrim) is generally considered first-line therapy for PCP (not to be confused with Sulfadiazine+pyrimethamine which is first line for toxoplasmosis). However, atovaquone may be used in patients who cannot tolerate, or are allergic to, sulfonamide medications such as TMP-SMX. In addition, atovaquone has the advantage of not causing myelosuppression, which is an important issue in patients who have undergone bone marrow transplantation.
Atovaquone is given prophylactically to kidney transplant patients to prevent PCP in cases where Bactrim is contraindicated for the patient.
Malaria.
Atovaquone, as a combination preparation with proguanil, has been commercially available from GlaxoSmithKline since 2000 as Malarone for the treatment and prevention of malaria.
Research.
COVID-19.
Preliminary research found that atovaquone could inhibit the replication of SARS-CoV-2 in vitro. Clinical trials of atovaquone for the treatment of COVID-19 are planned.
Atovaquone has also been found to inhibit human coronavirus OC43 and feline coronavirus in vitro.