New research from Australian National University and Germany's University of Heidelberg indicates that chloroquine, the cheap anti-malarial drug used to treat and prevent malaria, simply need to be administered differently.

The parasite that causes malaria has developed resistance to chloroquine, but researchers that the parasite protein that causes resistance has an Achilles' heel.

"We studied diverse versions of this protein and in all cases found that it is limited in its capacity to remove the drug from the parasite," researcher Dr. Rowena Martin from the ANU Research School of Biology said in a statement. "This means malaria could once again be treated with chloroquine if it is administered twice-daily, rather than just once a day."

Martin and her colleagues found that the protein may have developed resistance to chloroquine.

"We found that the protein gains the ability to move chloroquine out of the parasite through one of two evolutionary pathways, but that this process is rigid -- one wrong turn and the protein is rendered useless," Martin said. "This indicates that the protein is under conflicting pressures, which is a weakness that could be exploited in future antimalarial strategies."

Chloroquine is still used in developing nations in the South Pacific, Africa, Asia and South America, but has been withdrawn from use in many developed countries.

Martin said the findings could be used to help millions of people in developing nations who are at risk of catching malaria. There is also potential to apply the findings to several chloroquine-like drugs that are also becoming less effective as the malaria parasite builds up resistance.

However, researchers do not recommend taking larger doses of chloroquine.

"The key is to increase the frequency of chloroquine administration, for example by taking a standard dose in the morning and another at night. If you take too much all at once it can kill you," Martin added.