After testing 1000’s of medicines currently approved or going through clinical studies, investigators have recognized 2 groups of substances that can deal with Zika virus infections in 2 ways. One way stops the virus duplicating in the body, and the other way stops the virus activity in fetal brain cells that results in birth defects in newborns.
Although initially recognized in monkeys and then people in Africa just after World War II, it is only lately that we have figured out Zika virus can cause birth problems like as microcephaly and Guillain-Barré syndrome in people.
The new research, presented in Nature Medicine, is a cutting-edge because it indicates effective therapies for Zika could be just around the corner, without needing to wait for several years it generally takes to develop a new medicine from scratch.
Hengli Tang, a professor of biological science and one of the senior investigators on the current study, describes:
“We targeted on substances that have the smallest path to clinical use. This is an initial step towards a therapeutic that can cease transmission of this condition.”
One of the substances he and his colleagues identified is the foundation for a drug known as Niclosamide that is accepted by the Food and Drug Administration (FDA). The medicine is generally used to treat tapeworm and animal research show it is safe for use in pregnancy.
In theory, physicians could recommend the drug today, but it requires to go through tests to repurpose it as a therapy for Zika virus infection.
A few months ago, members of the study team had identified a connection between Zika and microcephaly – a serious birth defect where infants are born with a significantly smaller head and brain. This resulted in the search for drug substances that might protect against the viral damage.
Repurposing screen sifted via 6,000 current drugs
For their new research, the study team formulated a drug repurposing screen, a comparatively new method that investigators are using to accelerate drug development.
The team tested 6,000 substances that were either already accepted by the FDA or were going through clinical studies. In either case, the route to discovering a successful candidate for Zika therapies would be significantly shorter than developing a new medicine from scratch.
The two classes of substances they recognized are able of defending brain cells from cell death caused by Zika virus activity.
One class of substances is antiviral in nature and prevents the virus multiplying.
The other class of substances is neuroprotective in nature and prevents the virus holding out cell-damaging “caspase-3 activity” in human cortical neural progenitors – precursors to brain cells in fetal development.
When they examined combination therapies using one substance from each category – antiviral and neuroprotective – the investigators identified they enhanced protection of precursor cells from cell death caused by the Zika virus.
The investigators are ongoing to work on the substances and hope to start examining them on animal models of Zika infection shortly.