Tafenoquine and its potential in the treatment and relapse prevention of <em>Plasmodium vivax</em> malaria: the evidence to date

Abstract

Despite declining global malaria incidence, the disease continues to be a threat to people living in endemic regions. In 2015, an estimated 214 million new malaria cases and 438,000 deaths due to malaria were recorded. Plasmodium vivax is the second most common cause of malaria next to Plasmodium falciparum. Vivax malaria is prevalent especially in Southeast Asia and the Horn of Africa, with enormous challenges in controlling the disease. Some of the challenges faced by vivax malaria-endemic countries include limited access to effective drugs treating liver stages of the parasite (schizonts and hypnozoites), emergence/spread of drug resistance, and misperception of vivax malaria as nonlethal. Primaquine, the only 8-aminoquinoline derivative approved by the US Food and Drug Administration, is intended to clear intrahepatic hypnozoites of P. vivax (radical cure). However, poor adherence to a prolonged treatment course, drug-induced hemolysis in patients with glucose-6-phosphate dehydrogenase deficiency, and the emergence of resistance make it imperative to look for alternative drugs. Therefore, this review focuses on data accrued to date on tafenoquine and gives insight on the potential role of the drug in preventing relapse and radical cure of patients with vivax malaria.

Inhibition of Severe Acute Respiratory Syndrome Coronavirus 2 main protease by tafenoquinein vitro

“…TFQ (brand name Krintafel/Kozenis in U.S./Australia, owned and developed by GlaxoSmithKline) is an 8-aminoquinoline anti-malarial drug that was approved by the U.S. FDA in July 2018 and the Australian Therapeutic Goods Administration (TGA) in September 2018 for the radical cure of Plasmodium vivax (12)(13)(14), a parasite that causes malaria. In addition, TFQ (brand name Arakoda/Kodatef in U.S./Australia, owned by 60 Degrees Pharmaceuticals) was later approved by the FDA and the TGA for malaria prophylaxis (14,15).…”

A Brief Review on Tafenoquine in Relapse Malaria

“…It is recommended to test the G6PD status of the individual prior to the initiation of the therapy as this drug may cause hemolytic anemia and hemolysis in patients with G6PD deficiency. [12][13][14]…”

Tafenoquine: A Breakthrough Drug for Radical Cure and Elimination of Malaria

“…TQ is unique in the sense that it has a very long half-life and, like PQ, is active against the preerythrocytic form (liver), the erythrocytic form (asexual), and the gametocytes of the Plasmodium species, that includes P. vivax and P. falciparum. [11][12][13][14][15] TQ exhibits extensive protein binding of over 99.5% and in a healthy adult has a volume of distribution of ≈2,470 L with an interindividual variability of 24.1%. Though its full excretion profile is unknown, metabolism of TQ is slow.…”