According to the Daily Mail, the pill works by re-tuning the immune system in asthmatics so it does not overreact when a person is exposed to mite droppings, which are one of the leading causes of asthma attacks.
Dust mite droppings typically prompt the immune system to produce antibodies, which cause a large-scale release of the chemical histamine. Histamine, in turn, causes irritation and swelling of the airways, Fox News reported.
By exposing people to small amounts of a protein found in mite droppings, the researchers said they could essentially re-tune the immune system to stop interpreting the proteins as a threat and thus prevent the rush of histamine.
The British newspaper said early trial results indicate people who take the pill every day substantially reduce their use of steroidal inhalers.
In a study of 600 asthma sufferers, one in three were able to stop using their inhalers.
"We know some people find inhalers difficult to use, and asthma medicines can have side-effects if taken in high doses or for a long time, so we look forward to when this research can be translated into an alternative treatment," Leanne Metcalf from Asthma UK told the paper.