Biological therapy was associated with significant changes in lung structure and, by extension, improved lung function in individuals with chronic obstructive pulmonary disease (COPD) and T2 inflammation, according to new data presented at the European Respiratory Society Congress.

Biologics are known to reduce exacerbations in individuals with COPD and T2 inflammation, but the impact of these medications on disease progression remain unclear, according to Truong-An (Andrew) Ho, MD, a pulmonologist at of Temple University Hospital, Philadelphia, and colleagues.

“We hypothesized that biologics may have an effect in mitigating structural changes and sought to use quantitative CT imaging to objectively measure airway wall thickness and emphysema,” Ho said in an interview.

The researchers examined imaging data from 23 adults with COPD and T2 inflammation from before and after treatment with biologics; 17 received mepolizumab, 5 received benralizumab, and 1 received dupilumab. The mean age of the participants was 69 years, 56.5% were women, and the mean baseline predicted forced expiratory volume in 1 second (%FEV₁ predicted) was 43.

Patients who underwent bronchoscopic lung volume reduction were excluded from the study to better assess the impact of biologics on lung structural changes.

Measures of structural changes in the lungs were based on low attenuation area percentage (%LAA) to assess emphysema and on the perimeter-adjusted internal perimeter 10 (Pi10) and airway wall percentage (WA%) to assess airway remodeling. Data were compared between baseline and an average follow-up of 817 days.

Patients with improved measures of Pi10 and WA% after a period of biological therapy showed significant improvement in lung function and were associated with significant %FEV₁ increases (11.25% and 11.88%; P = .035 and P = .08, respectively).

Patients with an extended follow-up period of an average of 1085 days showed a trend toward reduced %LAA, fewer hospitalizations, and fewer mean exacerbations per year.

“When looking at the total cohort, there were no significant differences between emphysema scores and wall thickness in the year prior and year post-initiation of biologic therapies,” Ho told Medscape Medical News. “While we know these medications can reduce exacerbations, structural changes likely lag behind, and it is not surprising that they may take longer to be seen,” he said.

Ho said he was encouraged that patients with objective imaging improvements showed an association with decreases in exacerbations and hospitalizations (for %LAA) and improvements in %FEV₁ (for Pi10 and WA%). “There was also a trend toward reduced emphysema scores in patients who had longer-term follow-up, suggesting that an extended follow-up may be needed to fully assess benefit,” he said.

Ho acknowledged the study’s limitations, notably the small sample size and use of data from a single center. The next steps for research are larger, prospective studies over a longer period to identify significant long-term benefits associated with biologics, he said.

However, the results suggested that the benefits of biologics may extend beyond exacerbation reduction, with the potential to influence long-term structural changes in the lungs, he noted.

Small Size and Sicker Patients Limit Clinical Implications

The current study addresses the clinically relevant question of whether expensive biological therapies, which have been shown to reduce exacerbations and improve quality of life, also permit lung repair or at least slow lung destruction, said Jeffrey L. Curtis, MD, a pulmonologist and professor of internal medicine at the University of Michigan, Ann Arbor, Michigan, in an interview.

However, the results should be interpreted with caution, as the analysis is very preliminary, said Curtis, who was not involved in the study.

“The sample size is quite small and quite sick at baseline (61% and 74% had COPD and hypertension, respectively), likely reflecting the referral patterns to Temple,” he said.

Another caution in the findings is the statistical test used in the study, which was not specified but may not be appropriate for a small sample size, Curtis told Medscape Medical News. “The observed mean reduction is heavily driven by the absolute change in several ‘responders,’ and the more appropriate median response might or might not hold up to a nonparametric test, with six responders, three who worsened, and two essentially unchanged,” he said.

However, a study in a larger sample using VA pharmacy and lung cancer screening CT data could be conducted to confirm the results, Curtis added.

The study reported receiving no outside funding. Ho and Curtis disclosed having no financial conflicts to disclose.