Asthma is a common respiratory disease that affects about 8 percent of the U.S. population. It causes a person’s airways to narrow and produce extra mucus, which makes breathing difficult. Symptoms vary from person to person, from a minor wheeze and cough to life-threatening narrowing of the airways.
Most people with asthma can be treated with special inhaled steroids called glucocorticoids, which were first used in the early 1970s and have significantly reduced the number of asthma-associated deaths.
However, currently available steroids are largely ineffective for mitigating attacks in people with severe asthma. In addition, prolonged use of inhaled glucocorticoids has been linked to hoarseness, minor growth reduction in children, decreased bone mass and high blood pressure in adults.
By studying the structure of various glucocorticoid receptors (molecules that interact with glucocorticoids when they are inhaled), Dr. Eric Xu and his collaborators have developed a series of highly potent glucocorticoids that could better manage severe asthma.
One, called VSG158, was particularly successful at alleviating inflammation and other symptoms in a model of severe asthma. It is 10-times more potent than the strongest currently available glucocorticoid, demonstrated fewer side effects overall and has chemical properties that would allow it to be dispensed through an inhaler.
The findings are extremely promising, says Xu, but now must be translated from a laboratory model into human studies.
“To our knowledge, VSG158 is the only glucocorticoid that has been shown to reverse steroid-resistant asthma in lab models,” he said. “When combined with its other properties, we believe it has enormous potential for development into a more powerful asthma medication that works for people facing the most tough-to-treat types of this condition.”
Terms to know
Asthma: A condition marked by swelling of the airways and production of extra mucus, which makes breathing difficult.
Glucocorticoid: A type of steroid that works with the immune system to reduce inflammation.
Receptor: A molecule that conveys messages between a cell and its environment by interacting with other molecules
The study was published in the Proceedings of the National Academy of Sciences. You can read it here.