A drug given to dogs to treat their cancer could be used to thwart Covid, scientists say.
Masitinib has been used in dogs for more than a decade, but is not yet approved for humans.
Academics already believe it may have potential in treating skin cancer, Alzheimer’s, asthma and multiple sclerosis.
But now researchers at the University of Chicago hope it can also offer hope in the fight against the coronavirus pandemic.
Lab trials of masitinib – which costs just £2 a pill – found it stopped the virus replication, eventually causing disease.
Studies showed it worked just as well against variants and other similar viruses that can make people sick.
The trial is not yet at the stage of giving the drug to Covid patients, but the smallest dose of the drug given to dogs will cost just £2
Drugs proven to work in the fight against Covid
Budesonide is a medication usually taken through an inhaler to treat asthma or chronic obstructive pulmonary disease.
An Oxford University study in April found that in two weeks, 32 percent of people recovered from Covid when they took the drug through an inhaler, compared with 22 percent without.
Budesonide is a corticosteroid, meaning it reduces swelling in the body and helps control immune responses.
In the lungs, swelling can make breathing difficult and cause coughing. Budesonide can open the airways to relieve these symptoms.
It costs around £15 for one inhaler and is available from the NHS.
Dexamethasone was the first drug found to reduce the death rate among patients hospitalized with Covid.
A study by the RECOVERY group found that the low-cost steroid dexamethasone can prevent death in one in eight ventilated coronavirus patients and one in 25 on respiratory support.
The steroid prevents the release of substances in the body that cause inflammation, making breathing difficult in Covid patients.
The drug is most commonly used to treat ulcerative colitis, arthritis, and some types of cancer.
It is given as an injection or as a daily tablet and costs £5 per patient and is available from the NHS.
A RECOVERY study found that the arthritis drug tocilizumab reduced the risk of death by an additional four percent, on top of the 20 to 35 percent reduction given by dexamethasone.
A study by the University of Oxford and the NHS found that the arthritis drug tocilizumab cuts the risk of dying from Covid by half when taken with dexamethasone.
This means that one extra life can be saved for every 25 people who receive the drug.
It was also found to reduce time in hospital by five days.
The anti-inflammatory drug is usually used to treat rheumatoid arthritis and similar conditions.
In Covid patients, it prevents a reaction in the lungs and airways that leads to breathing problems.
It is given to patients by injection into the veins and lasts four weeks at a time.
A typical dose of 480mg costs £614.40 and is available on the NHS.
But the trials were not conducted on humans, and the claims were based solely on testing the drug on mice and cell cultures.
The team is now planning human trials, hoping it will work — and they’re confident it will.
Professor Savas Tay, who led the study, said: ‘Inhibitors of the key protease of SARS-CoV-2, such as masitinib, may represent a new potential way to treat Covid patients, especially in the early stages of the disease.
“Covid will likely be with us for many years to come, and new coronaviruses will continue to emerge.
“Finding existing drugs with antiviral properties could be an essential part of treating these diseases.”
dr. Nir Drayman, who co-wrote the paper, said: ‘Masitinib has the potential to be an effective antiviral agent now, especially when someone is first infected and the antiviral properties of the drug will have the greatest effect.
This is not the first outbreak of the new coronavirus and it will not be the last. In addition to vaccines, we need new treatments to help those infected.’
Clinical trials for other diseases have shown that drugs branded as Masivet and made by the French firm AB Sciences are safe for humans.
But it can cause side effects such as diarrhea, vomiting, swollen ankles, feet and legs and increase the risk of heart disease.
The smallest dose of the drug given to dogs costs about £2. It’s not clear how much people would need if it worked.
Experts from the University of Chicago searched a list of nearly 2,000 drugs known to be safe for humans.
All the drugs they’ve researched can prevent cells from becoming infected with a separate coronavirus, called OC43, that causes the common cold.
They tested the drugs against SARS-CoV-2 to determine if it could work against the virus behind the pandemic.
Masitinib was found to be the most potent, according to the results of the study published yesterday in the journal Science.
Further tests found that it reduced the viral load — the amount of virus an infected person has — in mice by 99 percent.
Experts said the drug worked equally well on the Kent ‘Alpha’, South African ‘Beta’ and Brazilian ‘Gamma’ variants.
Researchers said it could also be effective against several types of coronaviruses and picornaviruses, including hepatitis A, polio and viruses that cause the common cold.
It works by binding to an enzyme found in coronaviruses called 3CL, and it stops working. The enzyme makes them replicate in cells.
Since the start of the Covid pandemic, scientists have been looking for effective treatments.
So far, the steroid dexamethasone and arthritis drug tocilizumab have been proven to work.
Dexamethasone is available on prescription from the NHS and costs £6 for 28 500g tablets. Tocilizumab can also be prescribed by the NHS in certain cases and costs £913 per 1ml injection.