Novel Malaria Treatment for Children Receives First Approval

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

GlaxoSmithKline’s tafenoquine can treat the Plasmodium vivax variety of malaria that is most prevalent 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 Jago, executive vice president of Medicines for Malaria.

Malaria

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

Most of these deaths in sub-Saharan Africa, home to a form of the malaria parasite called Plasmodium falciparum. Most deaths occur in children under 5 years of age. In October, WHO approved the first malaria vaccine against P. falciparum, also produced by GlaxoSmithKline.

P. vivax causes up to five million cases of malaria every year; children between the ages of 2 and 6 are four times more likely than adults to contract the disease.

The parasite is a slippery adversary that quickly changes different forms in the body. In the blood, the infection can cause acute symptoms of fever, chills, vomiting, and muscle pain.

P. vivax can also lurk in the liver, causing relapses months or even years after initial exposure. These episodes can lead to severe anemia, long-term brain damage, and death.

“It’s a brand name for vivax malaria,” Mr Jago said.

Mr Jago said

Most treatments, including chloroquine, target the blood stage of the parasite and therefore cannot prevent recurrence of the infection and associated symptoms. But tafenoquine destroys dormant colonies in the liver. When combined with chloroquine, tafenoquine can provide what scientists call a “radical cure.”

In July 2018, the Food and Drug Administration approved 300 milligrams of tafenoquine for the curative treatment of P. vivax malaria in adults and adolescents 16 years of age and older. Similar approvals have been followed by regulators in Australia, Brazil, Thailand and Peru.

The new formulation for children is given as one small 50mg tablet dissolved in water, which is much easier on children than the current seven- or 14-day course of tablets designed for adults, and therefore much more likely to be used. .

“Today we have the tool to stop the relentless relapse in both adults and children – we are one step closer to beating this disease,” said David Reddy, Chief Executive of Malaria Medicines, in a statement.

Drugs

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

The researchers evaluated different doses of the drug by weight for children aged 2 to 15 who weighed at least 22 pounds. The researchers recruited 60 children with P. vivax malaria from three locations in Vietnam and one in Colombia.

All children received a single dose of tafenoquine and a course of chloroquine prescribed in accordance with local or national guidelines for the treatment of active blood infection.

The researchers reported that about 62 percent of children reported some side effects. Which is in line with the percentage seen in adults and adolescents. None of the side effects were serious, although the treatment caused about one in five children to vomit.

After four months, the treatment was 95 percent effective in preventing relapse. Which is similar to that in adults and older adolescents.