New malaria treatment for children gets first approval

Australian regulators have approved a simple drug combination as an effective cure for a form of malaria in children ages 2 to 16, opening the door to approvals in other countries and heralding a new weapon in the fight against a deadly disease.

The drug is a single dose of tafenoquine (brand name Kozenis) administered along with traditional chloroquine treatment. The approval was announced Monday by the nonprofit Medicines for Malaria Venture, which helped develop the drug.

Tafenoquine, made by GlaxoSmithKline, can cure a type of malaria caused by Plasmodium vivax, which is most common in South and Southeast Asia, South America, and the Horn of Africa.

The drug will be submitted for approval in nine countries, as well as the World Health Organization, according to George Jagoe, an executive vice president at the Medicines for Malaria Venture.

Malaria is one of the deadliest infectious diseases. In 2019, there were 229 million new infections and 558,000 deaths; numbers rose during the Covid-19 pandemic to 627,000 deaths in 2020.

Most of these deaths occur in sub-Saharan Africa, where a form of the malaria parasite Plasmodium falciparum exists. A majority of deaths occur in children under 5 years of age. In October, the WHO approved the first malaria vaccine, also made by GlaxoSmithKline, against P. falciparum.

P. vivax causes up to five million malaria infections annually; children aged 2 to 6 are four times more likely than adults to contract the disease.

The parasite is a slippery opponent that quickly moves through various forms in the body. In the blood, the infection can cause acute symptoms of fever, chills, vomiting and muscle aches.

P. vivax can also hide in the liver, causing a relapse months or even years after the initial exposure. These episodes can lead to severe anemia, permanent brain damage, and death.

“That’s the trademark of vivax malaria,” Mr. Jagoe said.

Most treatments, including chloroquine, target the blood stage of the parasite and thus cannot prevent recurrence of the infection and associated symptoms. But tafenoquine goes after the sleeping colonies in the liver. When combined with chloroquine, tafenoquine can deliver what scientists call a “radical remedy.”

In July 2018, the Food and Drug Administration approved 300 milligrams of tafenoquine for the radical cure of P. vivax malaria in adults and adolescents 16 years of age and older. Drug regulators in Australia, Brazil, Thailand and Peru followed suit with similar approvals.

The new formulation for children is given as a single small 50-milligram tablet dispersed in water, which is much easier for children to take than the current seven- or 14-day pill regimen developed for adults – and therefore much more likely. used.

“Today we have a tool to end the relentless relapse for both adults and children — we are one step closer to beating this disease,” said David Reddy, the chief executive of the Medicines for Malaria Venture, in a statement.

Drugs for P. falciparum can be evaluated quickly, but because P. vivax causes recurrent malaria, trials require a much longer follow-up. “What you really prove with vivax treatments like this is that you won’t have a relapse in six months,” said Mr. jagoe.

Researchers evaluated different dosages of the drug, based on weight, for children ages 2 to 15 who weighed at least 22 pounds. The researchers recruited 60 children with P. vivax malaria from three sites in Vietnam and one in Colombia.

The children were all administered a single dose of tafenoquine and a course of chloroquine according to local or national guidelines for the treatment of the active blood stage infection.

About 62 percent of the children reported some side effects, a rate similar to that seen in adults and adolescents, the researchers reported. None of the side effects were serious, although the treatment caused vomiting in about one in five children.

After four months, the efficacy of the treatment in preventing recurrence was 95 percent, comparable to the efficacy in adults and older adolescents.

This post New malaria treatment for children gets first approval

was original published at “https://www.nytimes.com/2022/03/14/health/malaria-children-tafenoquine.html”