To inform the development of a national clinical guideline for Chronic Obstructive Pulmonary Disease (COPD), prioritised by the National Clinical Effectiveness Committee (NCEC) in Ireland, a systematic review was conducted to examine the cost-effectiveness of long-acting beta2-agonists (LABAs) in combination with long-acting muscarinic antagonists (LAMAs) compared with LAMA or LABA monotherapy.

Medline, Embase, the Cochrane Library and grey literature sources were searched up to 19 June 2018. Studies evaluating cost-effectiveness published post-2008 in English were included. Screening, data extraction, and quality assessment using the Consensus Health Economic Criteria (CHEC-list) and International Society for Pharmacoeconomics (ISPOR) questionnaires were conducted independently by two reviewers. Costs were adjusted to 2017 Irish Euro using consumer price indices and purchasing power parity as per national guidelines.

From a total of 8,661 articles identified, nine studies (all cost-utility analyses) were included in the review. Studies ranged from low to high quality and compared LAMA/LABA combination therapy with LAMA monotherapy. The results reported were mixed, ranging from combination therapy being dominated by (that is, more costly and less effective than) LAMA monotherapy to being dominant (that is, less costly and more effective). However, when excluding low quality, less applicable studies, the remaining six studies reported incremental cost-effectiveness ratios (ICERs) of between EUR 2,770 and EUR 26,462 per quality-adjusted life year (QALY) gained. Only one study additionally compared LABA monotherapy as a comparator, reporting combination therapy to be even more cost-effective than in the LAMA monotherapy comparison.

Applying a cost-effectiveness willingness-to-pay threshold of EUR 45,000 per QALY gained, this systematic review found that LAMA/LABA combination therapy is cost-effective compared with LAMA or LABA monotherapy in COPD patients.