Researchers from Indian Institute of Technology (IIT), Mandi, have identified a drug target in the Zika virus that can bind with an existing antimalarial drug to inhibit the spread of the disease in the human body.
Zika is a viral disease transmitted by the aedes aegypti mosquitoes that also transmit diseases such as dengue and chikungunya. It is a self-limiting disease that causes fever, rashes, joint pain and red eyes, but in pregnant women it has been associated with babies born with microcephaly (a small head and abnormal brain development).
The researchers found that hydroxychloroquine (HCQ), a drug that is used to treat malaria, can inhibit the NS2B-NS3 protease necessary for the replication of the Zika virus.
“Ours was a three part research. First, we looked through existing FDA approved drugs and computationally discovered five molecules that could probably work against Zika. Then, we purified the protein target to see whether HCQ inhibited its functions. And, third, we did enzyme kinetic studies to find out the concentration at which the drug reduces the viral load,” said Rajanish Giri, assistant professor, department of biotechnology, IIT Mandi.
Giri’s team worked closely with Indira Mysorekar from Washington University at St. Louis, USA, to study the enzyme kinetic studies. Earlier, Mysorekar’s team had suggested that the use of HCQ can prevent the transmission of Zika from mother to foetus.
“There is a need for either drugs or vaccine against Zika because it is a public health concern as it has been associated with microcephaly. Till now, there is nothing. I haven’t heard of this particular study, but if an already existing drug can be used against the virus, if there is a proof of concept or enough evidence, then the drug development will take less time,” said PL Joshi, former director of the National Vector Borne Disease Control Programme.
As HCQ is already an approved drug in the USA and India, a translational drug that can be marketed for Zika would be easy to develop.
“Repurposing approved drugs can be an efficient method to identify drug compounds, which may be capable of activating or inhibiting new targets. There is no need to prove the safety of the drug, it can directly go into preclinical animal studies for its efficacy against Zika,” said Giri.