A new flu drug could be used to treat the virus and speed up recovery, a new study claims.
Until now, scientists have struggled to find a cure for the dreaded influenza since little was known about how it altered human lung cells.
But this week, a team of cancer researchers reveal they have accidentally discovered a formula which could flush the virus away.
Scientists at St Jude Children’s Research Hospital in New York were trying to devise a drug to kill tumors when they realized it had another clearer benefit: fighting the flu.
During their experiments, they found the compound could restore cells infected by flu, and stop the virus from reproducing, without building up drug resistance.
Scientists at St Jude Children’s Research Hospital in New York were trying to devise a drug to kill tumors when they realized it had another clearer benefit: fighting the
Putting it to the test, they managed to increase the survival rate of flu-infected mice.
Experts have hailed the discovery as a breakthrough that could be more attractive to the many people who skip their preventative flu jab every year.
The influenza virus turns infected lung cells into ‘factories’ that churn out thousands of copies of the virus to spread the infection.
The researchers showed that flu infection changed the metabolism of human lung epithelial cells, the prime location for replication of flu virus.
Study corresponding author Doctor Paul Thomas, of St. Jude Children’s Research Hospital in the US, said: ‘Previously, little was known about how flu infection changed the metabolism of lung epithelial cells; but based on early evidence in this study we suspected metabolism was an Achilles heel of the virus. We were not disappointed.’
Dr Thomas said the alteration radically increased the cells’ dependence on glucose and glutamine, which are the raw materials of viral production.
Scans showed ‘dramatically increased’ glucose metabolism in the lungs of 20 immune-compromised pediatric cancer patients with flu and other respiratory infections compared to patients without infections.
Working with colleagues who study rapidly dividing tumour cells, the researchers screened 80 small molecules and drugs that targeted cell metabolism rather than the virus.
They identified several, including the investigational cancer drug BEZ235, which blocked a key metabolic pathway in flu-infected human lung epithelial cells.
Researchers showed that BEZ235 reversed infection-induced metabolic changes in the cell and reduced production of new flu virus.
They said the drug also eased respiratory symptoms and significantly improved survival of mice infected with a pandemic flu strain.
Dr Thomas said vaccines and medications can help prevent or lessen flu, but neither is a match for the rapidly changing virus.
Vaccines must also be reformulated annually, and some flu strains are now resistant to anti-viral drugs.
Dr Thomas said: ‘By focusing on changing how infected cells respond to the resulting metabolic stress rather than targeting a component of the virus itself, there is less risk that the virus will become resistant to the drugs..’
BEZ235 is being tested in clinical trials for treatment of solid tumours. While using a cancer drug to treat a flu infection might sound surprising, Dr Thomas noted that tumour cells are also metabolically active.
He said BEZ235 works as a cancer drug by inhibiting the PI3K and mTOR metabolic pathways, which help fuel the unchecked cell division that is a hallmark of cancer.
Working in human lung epithelial cells, researchers used a variety of techniques to show that flu infection increased activity of the PI3K and mTOR pathways and that BEZ235 restored PI3K and mTOR activity to pre-infection levels.
Although the drug didn’t block the virus from infecting human lung cells, the researchers showed that BEZ235 reduced viral replication by limiting the ability of the infected cells to use glucose and glutamine to fuel production of more flu viruses.
Dr Thomas added: ‘This approach works by reducing viral replication, which suggests there might be a treatment window that lasts several days in which drugs could be used to reduce the infection and risk of complications.’
The findings were published in the journal Cell Reports.
24 May 2017