Three professors at the University of Southampton school of medicine have become millionaires after making a “major breakthrough” in the treatment of Covid-19 patients.

As soon as the clinical trial of their drug’s results was published on the morning of July 21, the shares had risen by 540 percent by lunchtime, reports The Guardian.

The trial also found that 79 percent of patients given the drug are less likely to be seriously ill.

Almost two decades ago professors Ratko Djukanovic, Stephen Holgate and Donna Davies discovered that people with asthma and chronic lung disease lacked a protein called interferon beta, which helps fight off the common cold.

They worked out that patients’ defences against viral infection could be boosted if the missing protein were replaced.

The academics created the company, Synairgen, to turn their discoveries into treatments. It floated on the stock market in 2004 but its shares collapsed after a deal with AstraZeneca to treat viral infections in asthmatics fell through.

But when the need for any potential therapeutics for breathing difficulties are in high demand during the coronavirus pandemic, suddenly the professors’ discovery was seen as a game changer.

Richard Marsden, Synairgen’s chief executive, said the company had been deeply involved in a trial using the interferon beta drug to help people with chronic bronchitis or emphysema. “[But] when the coronavirus pandemic emerged, even back in January we realised that we might have an important role to play in defence against this virus,” he said.

“So we set about getting a clinical trial set up in February and March in anticipation of the virus coming to the UK, [and] it did. The trial was in place when people started to fill the hospitals up.”

Results of the initial trial, published this week, showed that coronavirus patients in hospital given a special formulation of the professors’ interferon beta drug, called SNG001, delivered directly to their airways via a nebuliser, were two to three times more likely to recover than those given a placebo.

The study of 101 people showed that the odds of patients developing a severe version of the disease were reduced by 79 percent, and their breathlessness was also “markedly reduced”, the company said.

So far this year, Synairgen’s shares have risen by more than 3,000 percent, to 204p at market close on Friday, valuing the company directors’ combined 2.6 percent stake at more than £7m.

Synairgen, which is still based at Southampton general hospital, is now presenting its findings to medical regulators around the world to seek approval for the next stage in bringing the treatment to market.

New drug approval procedures often take months, but governments have promised to speed up the process to get promising coronavirus treatments approved.

The company has also expanded the trial to patients suffering from milder coronavirus infections at home.

Synairgen has already ordered the drug manufacturer Rentschler to start producing supplies, with the aim of getting more than a million doses ready for a possible second wave of coronavirus in the winter.

In the future the drug could be given to healthcare workers and vulnerable groups prior to a second wave of Covid-19 or another new virus.