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Experimental treatment helps patients hospitalized with COPD

Inhaled hyaluronan benefited hospitalized COPD patients who needed breathing support. lisafx / iStock / Getty Images Plus

People with chronic obstructive pulmonary disease (COPD) can no longer take in all the air they need. COPD often causes shortness of breath, wheezing, and chest tightness. People may also cough up large amounts of mucus. Smoking and air pollution are the main causes of the lung disease. 

Current COPD treatments include inhaled steroids, antibiotics, and drugs called bronchodilators that help open the airways. Scientists are interested in developing new drugs for COPD. A research team led by Drs. Stavros Garantziotis of NIH’s National Institute of Environmental Health Sciences (NIEHS) and Raffaele Incalzi of Campus Bio-Medico University and Teaching Hospital in Rome, Italy, investigated the use of hyaluronan.

Hyaluronan is a long-chain sugar that’s naturally secreted by many tissues, including within the lungs. Part of the supporting scaffold that forms outside of cells, it plays an important role in wound healing and reducing inflammation. Hyaluronan has both lubricating and hydrating properties. It’s used in cosmetics as a skin moisturizer and in nasal sprays to moisturize airways. In animal studies, inhaled hyaluronan treatment has been shown to reverse some types of COPD.

The researchers examined whether inhaled hyaluronan might benefit hospitalized COPD patients who needed breathing support. Their findings were published in Respiratory Research, on February 1, 2021.

The team randomly assigned 41 participants to receive inhaled hyaluronan or an identical-looking placebo. The study was conducted in Italy, where hyaluronan is approved for airway moisturization. Patients in the study had been hospitalized for severe breathing trouble related to COPD. All required ventilation through a mask. The patients inhaled hyaluronan or a placebo twice daily.

The researchers found that inhaled hyaluronan treatment shortened the amount of time that patients needed support from the ventilator and improved their lung function. Those receiving hyaluronan also had lower levels of inflammation in their blood.

To understand how hyaluronan might work, the team conducted studies in the lab with lung cells from COPD patients and healthy donors. The researchers suspected that hyaluronan might help move the thick mucus that collects in the lungs of people with COPD. Healthy cells exposed to cigarette smoke in culture and cells from COPD patients in culture both developed less thick mucus after receiving hyaluronan.

Earlier studies from the researchers give insight into why inhaled hyaluronan may be an effective COPD treatment. Exposure to pollution causes hyaluronan in the lungs to break down into smaller fragments. These fragments irritate lung tissue and activate the immune system. This leads to constriction and inflammation of the airways. Reintroducing full-length hyaluronan may restore balance, reducing inflammation and helping to slow COPD.

“Studying the effect of pollution on the lungs helped us discover treatments for lung disease,” Garantziotis explains, “because pollution-induced lung damage and chronic lung disease share many characteristics, like the role of hyaluronan.”

“Inhaled hyaluronan…is safe and easy to administer,” Incalzi says. “Furthermore, it acts locally, only in the bronchial tree, and thus cannot interfere with any systemic drug.”

Larger studies are planned to further test hyaluronan for COPD other lung diseases and to determine the doses and conditions that may produce the most benefit.