Trimbow, which combines the inhaled corticosteroid (ICS) beclometasone, the long-acting ß2 agonist (LABA) formoterol, and the long-acting muscarinic antagonist (LAMA) glycopyrronium, is the first triple combination metered-dose inhaler to be licensed for asthma.
It is indicated for maintenance treatment of asthma in adults who are not adequately controlled on a LABA and medium dose of ICS, and who experienced one or more asthma exacerbations in the previous year.
Trimbow's new licence follows the recent launch of another triple combination inhaler for asthma, the dry powder capsule-based device Enerzair Breezhaler (mometasone/indacaterol/glycopyrronium).
The active components of Trimbow are formulated as extrafine particles, which results in a more potent effect of beclometasone than non-extrafine formulations. Each delivered dose of Trimbow contains 87 micrograms of beclometasone dipropionate, 5 micrograms of formoterol fumarate and 9 micrograms of glycopyrronium.
Trimbow is already approved as maintenance treatment in adults with moderate to severe COPD who are not adequately treated by the combination of an ICS and a LABA. The recommended dose of Trimbow in both asthma and COPD is two inhalations twice daily.
Improved lung function
Two randomised, double-blind 52-week phase III trials showed that extrafine beclometasone/formoterol/glycopyrronium triple therapy improves lung function and reduces exacerbations in adults with asthma compared with extrafine beclometasone/formoterol dual therapy.
TRIMARAN compared extrafine beclometasone/formoterol/glycopyrronium 87/5/9 microgram with extrafine beclometasone/formoterol 85/5 microgram, both taken as two puffs twice daily. TRIGGER evaluated a higher triple therapy dose of 172/5/9 microgram which is not currently available to prescribe in the UK.
Participants in TRIMARAN (n=1155) had uncontrolled asthma, a history of one or more exacerbations in the previous year, and had previously been treated with ICS and LABA. There was no requirement to demonstrate persistent airflow limitation following short-acting ß2 agonist use.
Compared with the dual therapy group, the triple therapy group showed benefit in both co-primary endpoints: a 57ml increase in pre-dose FEV1 at week 26 (95% CI 15–99; p=0.0080) and a 15% reduction in the rate of moderate and severe exacerbations over 52 weeks (rate ratio 0.85, 95% CI 0.73–0.99; p=0.033).
The most frequently reported adverse reactions of beclometasone/formoterol/glycopyrronium in patients with asthma are dysphonia (1.5%) and oral candidiasis (0.3%), which are normally associated with ICS; muscle spasms (0.2%), which can be attributed to the LABA component; and dry mouth (0.5%), which is a typical anticholinergic effect.
In patients with asthma, adverse reactions of the triple combination tend to cluster during the first 3 months of therapy and become less frequent with longer-term use.