Statins: The Next Class of Inhaled Drugs?

An emerging area of investigation in asthma and chronic obstructive pulmonary disease (COPD) is use of statins. The basis for this interest is epidemiological data linking statin use with improvements in lung health, and reductions in asthma-related hospitalizations and emergency room visits. Specific areas where researchers have identified improvements include intubation rates, and forced vital capacity.

Animal and in vitro studies suggest that statins have potential anti-inflammatory, antiproliferative, antioxidant, and immunomodulatory effects. These effects might help soothe the raging beast that asthma can become.

To date, many researchers have structured and conducted clinical trials using statins in patients who have asthma. The journal Expert Review of Respiratory Medicine examines statin use in pulmonary disease in an article published ahead of print. Their particular focus is use of inhaled statins.

Clinical trials using statins for the treatment of asthma have yielded conflicting results, and some researchers suggest that inadequate statin levels in the airway compartment might explain differences.

A good portion of this article is devoted to heavy science. For example, the authors discuss statins and their role in the mevalonate (MA) pathway. MA signaling is heavily entwined in lung biology and asthma. This article also discusses clinical trials of oral statins in asthma, lab investigations, and the challenge of understanding systemic and inhaled administration of statins.

In terms of inhaled statins, the authors explain the rationale behind 'repurposing' older drugs for chronic illnesses. They note several advantages, including the financial benefits of using older or known drugs for new indications. It is important to note that developing any drug to be used in an inhaler presents its own set of challenges. Inhalation also has tremendous potential. Inhalation of statins bypasses hepatic first-pass metabolism, and allowing clinicians to use significantly lower doses than needed orally.

The article ends with the section on expert commentary. In it, experts in the field acknowledge that ongoing investigations may reveal that oral statins have no clear clinical benefits. If that is the case, the scientific community supports repurposing statins for delivery via inhalation.

Patients who have asthma may soon find inhaled statins useful to control their disease. Definitive studies are needed before statins will become standard of care.

Reference

Zeki AA, Elbadawi-Sidhu M. Innovations in asthma therapy: is there a role for inhaled statins? Expert Rev Respir Med. 2018 May 3:1-13. doi: 0.1080/17476348.2018.1457437. [Epub ahead of print]