A new drug appeared to show promise in reducing rates of chronic obstructive pulmonary disease (COPD) symptoms in former and current smokers, according to results from late-stage clinical trials.

The medication, called tozorakimab and developed by AstraZeneca, is the first biologic drug to show efficacy in treating COPD symptoms, according to Dr. Frank Sciurba, professor of Pulmonary and Critical Care Medicine, University of Pittsburgh, in an AstraZeneca press release.

The results were presented at the European Respiratory Society Congress conference on Tuesday and set to be published in a peer-reviewed journal. 

Patients taking inhaler regimens for COPD management, which is the current standard of care, were randomized to receive either 300 milligrams of tozorakimab once every four weeks via injection or a placebo in two separate clinical trials sponsored by AstraZeneca.

The results from the two clinical trials demonstrated a significant reduction in moderate and severe COPD symptoms in the form of exacerbations compared to placebo, according to data released by AstraZeneca.

The reductions ranged from 29% to 34% in former smokers and 29% to 30% among current and former smokers. 

Aside from reactions at the injection side, tozorakimab was well-tolerated without any significant side effects reported, according to AstraZeneca.

Tozorakimab is being developed by AstraZeneca as a first-in-class monoclonal antibody binding interleukin-33, a protein released by damaged cells that triggers inflammation in conditions such as COPD.

There are other ongoing investigations sponsored by the company to evaluate tozorakimab for potential use in asthma and lower respiratory tract disease.

Tozorakimab has been accepted for priority review by the Food and Drug Administration (FDA) as an add-on maintenance drug for adults with COPD, AstraZeneca said. This means the agency will expedite the review for potential FDA approval.

Nearly 16 million U.S. adults have COPD, a group of lung diseases that get worse over time, according to the Centers for Disease Control and Prevention (CDC).

The most COPD types are emphysema and bronchitis, the CDC says. There is no cure for COPD and treatment requires lifestyle changes, such as quitting smoking, or therapies such as medications. Tobacco smoke is the main cause of COPD in the U.S., according to the CDC.

COPD is one of the top 10 leading cause of death in the U.S., according to the CDC. The American Lung Association says that in 2021, more than 138,825 people died from COPD.

COPD is often called a “smokers’ or former smokers’ disease,” but as many as one in four patients with COPD have never smoked, according to the CDC.

“Today’s groundbreaking tozorakimab results, from two replicate trials, set a new standard for COPD treatment outcomes in a broad population of patients,” Sharon Barr, executive vice president of BioPharmaceuticals R&D at AstraZeneca, said in a statement.

“AstraZeneca has validated the novel approach of targeting the two forms of IL-33 to both decrease inflammation and disrupt the cycle of mucus dysfunction. With our FDA Priority Review, we look forward to bringing this treatment to patients as quickly as possible,” Barr’s statement added.

Dr. Jennifer Miao is a board-certified cardiologist and a member of the ABC News Medical Unit.