Bronchial thermoplasty (BT) for the treatment of severe uncontrolled asthma was noninferior to biologics as assessed by patient quality-of-life (QOL) scores, according to meta-analysis findings published in Respiratory Medicine.
Bronchial thermoplasty, an interventional procedure that reduces airway smooth muscle mass by delivering controlled thermal energy to the airway wall, has shown favorable safety and efficacy. However, BT has not been directly compared with biologicals for asthma.
Investigators therefore conducted a network meta-analysis to assess how BT for the treatment of severe asthma compared with the use of biologicals approved by the US Food and Drug Administration (FDA). The researchers compared BT to biologicals by using prior research to generate probability-based safety and efficacy rankings of BT, biologicals, and control interventions (ie, placebo, standard of care, or sham BT) for 6 outcome measures: (1) the number of patients experiencing at least 1 exacerbation; (2) the annualized exacerbation rate ratio (AERR); (3) asthma control, based on Asthma Control Questionnaire (ACQ) scores; (4) quality of life, based on Asthma Quality of Life Questionnaire (AQLQ) scores; (5) oral corticosteroid dose reduction (OCDR) levels; and (6) lung function, as assessed by morning peak expiratory flow rate (amPEF).
The investigators searched the Cochrane Central Register of Controlled Trials, EMBASE, and PubMed databases without language restriction from inception to May 2022 for randomized controlled trials (RCTs) of BT and FDA-approved biologics for severe asthma. Analysis included 29 RCTs with 14,656 patients (mean age, 39 to 55 years; 61.2% women; pre-bronchodilator forced expiratory volume in 1 second percent predicted [FEV1pp] range, 51.6% to 80.9%). Most of the included studies had low risk of bias evaluated using the Cochrane Risk of Bias 2 tool.
This NMA of RCTs shows that BT is non-inferior to biologicals as a treatment modality for severe asthma in terms of improvements in asthma control scores, and that it may possibly be noninferior for the outcomes of exacerbation rate reduction, lung function improvement, and oral corticosteroid dose reduction.
Investigators found fewer patients treated with BT vs control interventions experienced at least 1 asthma exacerbation (risk ratio [RR], 0.66; 95% CI, 0.45-0.98). Improvements were significant in AQLQ score (mean difference [MD], 0.54; 95% CI, 0.30-0.77), ACQ score (MD, -0.41, 95% CI, -0.63 to -0.20), OCDR, and amPEF. There was no significance in the AERR patients in the BT vs control groups. Indirect comparisons of all studies showed no significant differences between biologics and BT.
Investigators noted BT remained similar in efficacy to biologicals and significantly superior to control interventions in subgroup analyses.
Review and network meta-analysis limitations include difficulty evaluating BT vs biologicals in methodological equivalence.
“This NMA of RCTs shows that BT is non-inferior to biologicals as a treatment modality for severe asthma in terms of improvements in asthma control scores, and that it may possibly be noninferior for the outcomes of exacerbation rate reduction, lung function improvement, and oral corticosteroid dose reduction,” investigators concluded. They wrote, “The present analysis provides an impetus for future RCTs comparing BT vs biologicals, to support the indirect comparisons derived from this study.”
Disclosure: One study author declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.