As current medications for malaria become less effective due to drug resistance, researchers have revealed that a peptide they isolated from an Antarctic sponge shows promise as a lead for new therapies.

The study was published in 'Journal of Natural Products.' Some 219 million cases of malaria were reported worldwide in 2017, according to the World Health Organization, with 4,35,000 people having lost their lives to their disease that year. Symptoms begin with fever and chills, which can be followed by severe anaemia, respiratory distress and organ failure. The parasite responsible for malaria is transmitted to people through mosquito bites. It spends some of its lifecycles first in the liver, where it reproduces, and then it moves into the blood.

Conventional treatments based on artemisinin and its derivatives hold the parasite in check when it is in patients' blood, but the parasites are increasingly becoming resistant to these medications. One solution is to attack the organism at an earlier stage in its lifecycle when there are fewer parasites, and resistance might not have developed yet. In their search for a suitable pharmaceutical weapon, Bill J. Baker and colleagues turned to sponges, which rely on an array of chemical defences to fight off predators. The team screened a collection of natural products extracted from a Southern Ocean sponge known as Inflatella coelosphaeroides.

One compound, which they dubbed friomaramide, blocked infection and development of the malaria parasite Plasmodium falciparum in liver cells in a culture dish as effectively as primaquine, one of the few existing liver-stage treatments. Friomaramide is also non-toxic to the liver cells themselves. The researchers determined that the compound is a linear peptide with a distinctive structure, which they said makes it a promising framework for producing new leads for malaria treatment.