LABA/LAMA combinations versus LAMA monotherapy or LABA/ICS in COPD: a systematic review and meta-analysis

BACKGROUND Randomized controlled trials (RCTs) indicate that long-acting bronchodilator combinations, such as β2-agonist (LABA)/muscarinic antagonist (LAMA), have favorable efficacy compared with commonly used COPD treatments. The objective of this analysis was to compare the efficacy and safety of LABA/LAMA with LAMA or LABA/inhaled corticosteroid (ICS) in adults with stable moderate-to-very-severe COPD. METHODS This systematic review and meta-analysis (PubMed/MEDLINE, Embase, Cochrane Library and clinical trial/manufacturer databases) included RCTs comparing ≥12 weeks' LABA/LAMA treatment with LAMA and/or LABA/ICS (approved doses only). Eligible studies were independently selected by two authors using predefined data fields; the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. RESULTS Eighteen studies (23 trials) were eligible (N=20,185). LABA/LAMA significantly improved trough forced expiratory volume in 1 second (FEV1) from baseline to week 12 versus both LAMA and LABA/ICS (0.07 L and 0.08 L, P<0.0001), with patients more likely to achieve clinically important improvements in FEV1 of >100 mL (risk ratio [RR]: 1.33, 95% confidence interval [CI]: [1.20, 1.46] and RR: 1.44, 95% CI: [1.33, 1.56], respectively, the number needed to treat being eight and six, respectively). LABA/LAMA improved transitional dyspnea index and St George's Respiratory Questionnaire scores at week 12 versus LAMA (both P<0.0001), but not versus LABA/ICS, and reduced rescue medication use versus both (P<0.0001 and P=0.001, respectively). LABA/LAMA significantly reduced moderate/severe exacerbation rate compared with LABA/ICS (RR 0.82, 95% CI: [0.75, 0.91]). Adverse event (AE) incidence was no different for LABA/LAMA versus LAMA treatment, but it was lower versus LABA/ICS (RR 0.94, 95% CI: [0.89, 0.99]), including a lower pneumonia risk (RR 0.59, 95% CI: [0.43, 0.81]). LABA/LAMA presented a lower risk for withdrawals due to lack of efficacy versus LAMA (RR: 0.66, 95% CI: [0.51, 0.87]) and due to AEs versus LABA/ICS (RR: 0.83, 95% CI: [0.69, 0.99]). CONCLUSION The greater efficacy and comparable safety profiles observed with LABA/LAMA combinations versus LAMA or LABA/ICS support their potential role as first-line treatment options in COPD. These findings are of direct relevance to clinical practice because we included all currently available LABA/LAMAs and comparators, only at doses approved for clinical use.