Potential Zika Therapies Identified by Researchers
August 29 2016 - 12:00PM
Dow Jones News
Scientists have identified several potential therapies for the
Zika virus from among 6,000 drugs already commercially available or
undergoing clinical trials, according to a new study.
The research, published Monday in the journal Nature Medicine,
could help quicken discovery of medications for Zika and help
prevent the neurological disorders associated with it, including
microcephaly, a condition in which babies are born with abnormally
small heads.
The new paper identifies about a dozen substances—including a
long-used treatment for worm infections—that suppress the
pathogen's replication. Another molecule, currently in clinical
trials for liver disease, prevents brain cells in a dish from dying
following Zika exposure—a potentially important result given the
fetal-brain defects associated with the virus.
The study also suggests combinations of these two classes of
compounds could be the most effective way to treat Zika.
Simply preventing cell death could lead to chronic infection, so
it is also important to keep the virus from spawning, said Mariano
Garcia-Blanco, a virologist at the University of Texas Medical
Branch in Galveston who wasn't involved with the research.
Commercial drugs are rarely tested on pregnant women, so it is
unknown if the new results will help moms and their fetuses
directly, experts said.
"For drug development, pregnancy is a very dangerous place
people don't touch," said Hongjun Song, a neuroscientist at Johns
Hopkins University School of Medicine in Baltimore and one of the
lead authors on the study. "Here, we don't really have a choice. We
have a jump-start, [but]...there's a lot more to do."
The team tested drug candidates in stem cells and so-called
brain organoids, mini reconstructions of the developing brain. They
will need to validate their findings in animal models and
ultimately people.
Apart from niclosamide, the worm-killing medication, it is
unlikely the molecules shown to halt viral replication would be
approved for pregnant women because of potential toxic effects on
the fetus. But, virologists said, treating men and nonpregnant
women could decrease moms' risk of infection by reducing the amount
of virus circulating in people around them.
The work is part of a recent trend known as drug repurposing.
Rather than engineer compounds from scratch, scientists sift
through multitudes of already existing ones to see if any can treat
a particular disease.
This approach "is particularly useful for urgent [situations],"
like the Zika epidemic, during which scientists don't have time to
undergo the lengthy drug-discovery process, said Wei Zheng, a
researcher at the National Institutes of Health's National Center
for Advancing Translational Sciences and one of the study's lead
authors.
To move the research forward, the team will begin conducting
animal studies shortly, according to Dr. Zheng. They will also test
another 80,000 compounds with the help of robots, according to an
NIH spokesman.
The researchers have filed a patent covering the new findings.
The goal is to incite companies to commercialize the research and
develop Zika-busting drugs, said the NIH spokesman.
Pharmaceutical company Spotlight Innovation Inc. will bankroll
some of the team's future work through a partnership with Florida
State University's Hengli Tang, another of the study's lead
authors, according to Geoffrey Laff, Spotlight's senior vice
president of business development. The financial details weren't
disclosed, but amount to "several years of funding," Dr. Laff said.
Spotlight would license any resulting intellectual property, he
added.
The licensing may get complicated if the results involving
liver-disease drug emricasan hold up, and comparable alternatives
aren't found. The compound prevented cell death most potently among
molecules tested in the study.
Conatus Pharmaceuticals Inc. has several patents for it. Some
don't expire until 2028. A third party wanting to sell the molecule
would need to license it from Conatus, according to Paul Hasting
LLP's global chair for intellectual property Joseph O'Malley.
"Assuming that drug were to be found to treat Zika," he said,
"it would be bad news for the company. It would be under tremendous
pressure to license it for little or no money."
Alfred Spada, Conatus's chief scientific officer, said if
emricasan "were effective in the treatment of such a devastating
disease, I think we would be ecstatic."
Write to Daniela Hernandez at daniela.hernandez@wsj.com
(END) Dow Jones Newswires
August 29, 2016 11:45 ET (15:45 GMT)
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