A resistance-fighting antimalarial drug candidate is being tested in Australia. 

The candidate drug inhibits two essential enzymes required for the growth of malaria parasites and the spread of the disease through human-to-mosquito transmission. 

The initiation of this first-in-human trial is a crucial step in the development of a novel agent for the fight against malaria – a disease that kills more than 600,000 people each year.

This initial first-in-human study is designed to assess safety, tolerability and pharmacokinetics. The results from this study will inform the need for clinical development of this compound.

In pre-clinical studies the dual-targeting mechanism appears to confer a high barrier to the generation of resistance, an important criterion for malaria drug candidates. 

“In pre-clinical studies we’ve shown this compound inhibits two enzymes that process and activate key proteins that enable the parasites to move in and out of red blood cells,” Professor Alan Cowman, deputy director at WEHI and a Laboratory Head in the Infectious Diseases and Immune Defence Division, said.  

“The pre-clinical studies indicate that inhibiting these two enzymes – Plasmepsin IX (PMIX) and Plasmepsin X (PMX) – effectively disables the parasite from carrying out its key function of replicating and multiplying in the bloodstream. 

“The successful initiation of these first-in-human trials is an important milestone towards developing urgently-needed new treatments that could alleviate this major global health burden.”

As new malaria parasites increasingly become resistant to available drugs, the development of vaccines and novel antimalarial compounds to block transmission is vital in the fight against this killer disease. 

The compound is the result of an eight-year collaboration between the Walter and Eliza Hall Institute of Medical Research (WEHI) and global biopharmaceutical company MSD, dedicated to discovering new widely applicable malaria drug candidates.