Safety and Adverse Events after Targeted Lung Denervation for Symptomatic Moderate to Severe Chronic Obstructive Pulmonary Disease (AIRFLOW). A Multicenter Randomized Controlled Clinical Trial

Abstract

Rationale: Targeted lung denervation (TLD) is a bronchoscopic radiofrequency ablation therapy for chronic obstructive pulmonary disease (COPD), which durably disrupts parasympathetic pulmonary nerves to decrease airway resistance and mucus hypersecretion.Objectives: To determine the safety and impact of TLD on respiratory adverse events.Methods: We conducted a multicenter, randomized, sham bronchoscopy-controlled, double-blind trial in patients with symptomatic (modified Medical Research Council dyspnea scale score, ≥2; or COPD Assessment Test score, ≥10) COPD (FEV₁, 30-60% predicted). The primary endpoint was the rate of respiratory adverse events between 3 and 6.5 months after randomization (defined as COPD exacerbation, tachypnea, wheezing, worsening bronchitis, worsening dyspnea, influenza, pneumonia, other respiratory infections, respiratory failure, or airway effects requiring therapeutic intervention). Blinding was maintained through 12.5 months.Measurements and Main Results: Eighty-two patients (50% female; mean ± SD: age, 63.7 ± 6.8 yr; FEV₁, 41.6 ± 7.3% predicted; modified Medical Research Council dyspnea scale score, 2.2 ± 0.7; COPD Assessment Test score, 18.4 ± 6.1) were randomized 1:1. During the predefined 3- to 6.5-month window, patients in the TLD group experienced significantly fewer respiratory adverse events than those in the sham group (32% vs. 71%, P = 0.008; odds ratio, 0.19; 95% confidence interval, 0.0750-0.4923, P = 0.0006). Between 0 and 12.5 months, these findings were not different (83% vs. 90%; P = 0.52). The risk of COPD exacerbation requiring hospitalization in the 0- to 12.5-month window was significantly lower in the TLD group than in the sham group (hazard ratio, 0.35; 95% confidence interval, 0.13-0.99; P = 0.039). There was no statistical difference in the time to first moderate or severe COPD exacerbation, patient-reported symptoms, or other physiologic measures over the 12.5 months of follow-up.Conclusions: Patients with symptomatic COPD treated with TLD combined with optimal pharmacotherapy had fewer study-defined respiratory adverse events, including hospitalizations for COPD exacerbation.Clinical trial registered with www.clinicaltrials.gov (NCT02058459).

Keywords: anticholinergic; bronchoscopy; chronic obstructive pulmonary disease; nerves; targeted lung denervation.

Figure 1.

Respiratory adverse events between 3 and 6.5 months after bronchoscopy for the sham bronchoscopy and targeted lung denervation (TLD) groups. Respiratory events were lower respiratory tract complaints as defined by the investigator, including respiratory failure, pneumonia, chronic obstructive pulmonary disease exacerbation, influenza, respiratory infection, worsening bronchitis, worsening dyspnea, tachypnea, wheezing, or discovered airway effects that require a therapeutic intervention.

Figure 2.

(A) Time-to-first-event analysis: severe chronic obstructive pulmonary disease (COPD) exacerbations. (B) Time-to-first-event analysis: moderate or severe COPD exacerbations.