MADRID – Two newly published but previously reported phase 3 trials associated triple therapy in a single inhaler with a 23% reduction (P = .008) in asthma exacerbations relative to a two-drug inhaler, but fresh data from a prespecified analysis presented at the annual congress of the European Respiratory Society has identified those patients most likely to benefit.

“Six easily identifiable factors appear to be associated with the most prominent response to treatment and may help in the treatment step-up decision at the point of care,” reported Dave Singh, MD, professor in the division of infection, immunity, and respiratory medicine, University of Manchester (England).

The six factors associated with a lower relative risk (RR) of severe exacerbations were derived from the phase 3 TRIMARIN and TRIGGER trials. The primary results of these trials were presented several months ago at the 2019 American Thoracic Society (ATS) meeting, but the full data were published on the day that Dr. Singh spoke at the ERS.

To identify predictors of response, the pooled analysis of TRIMARIN and TRIGGER was prespecified. Both of these trials, which were similarly designed, compared a single inhaler of inhaled corticosteroids (ICS), long-acting beta agonist (LABA), and long-acting muscarinic antagonist (LAMA) to a single ICS/LABA inhaler.

On the basis of risk for severe exacerbations, greater protection from triple therapy relative to a conventional ICS/LABA inhaler was identified for those with a high degree of reversibility (defined as greater than 400 mL) relative to those with a lower degree (RR, 0.729; P = .024), those with a body mass index less than 25 kg/m² relative to a higher BMI (RR, 0.570; P = .005), those with only one exacerbation in the previous 12 months relative to those with more (RR, 0.731; P = .009), never-smokers relative to those with smoking history (RR, 0.764; P = .013), those younger than age 65 years relative to older (RR, 0.770; P = .17), and males relative to females (RR, 0.651; P = .009).

“This gives us six factors to consider when you are thinking about stepping up to triple therapy and are trying to determine which patients would benefit the most,” Dr. Singh said.

Both the TRIMARIN and the TRIGGER trials were double blind and placebo controlled. In both, the experimental arm was a single inhaler triple therapy of the ICS beclomethasone, the LABA formoterol, and the LAMA glycopyrronium. The control arm was a single inhaler combination of beclomethasone and formoterol. All inhalers were used twice daily.

TRIMARIN, with 171 participating sites in 16 countries, randomized 1,155 patients to the triple-drug inhaler with a moderate dose of ICS (100 mcg) or to the ICS/LABA inhaler. In TRIGGER, with 221 sites in 17 countries, 1,437 patients were randomized to one of three arms. Both the triple-drug inhaler arm and the ICS/LABA arm contained a higher dose of ICS (200 mcg) than in TRIMARIN. In an open-label third arm, patients also received the higher dose of ICS plus LABA and a second inhaler with tiotropium. The formoterol dose in all arms of both studies was 6 mcg.

As reported at the ATS and now published in the Lancet, the reduction in exacerbations on single inhaler triple therapy relative to ICS/LABA was significant when the data were pooled (even though the reduction in the TRIGGER study fell short of statistical significance). The median improvement in lung function for single inhaler triple therapy relative to ICS/LABA was significant in both TRIMARIN (57 mL; P = .008) and TRIGGER (73 mL; P = .0025).

In discussing the new pooled analysis of response predictors in TRIMARIN/TRIGGER, the ERS-invited discussant, Celeste M. Porsbjerg, MD, Bispebjerg Hospital, Copenhagen, expressed particular interest in reversibility. A positive reversibility test to salbutamol was an entry criterion for both trials, but Dr. Porsbjerg pointed out that a greater response in those with the highest reversibility suggests these patients have a phenotype in which bronchodilation is a more important driver of disease than is inflammation.

While conceding that this was possible, Dr. Singh cautioned that he considers these predictors of response to be “exploratory.” He believes that the TRIMARIN/TRIGGER studies were not designed to tease out the relative importance of mechanisms of asthma in response to the assigned therapies. However, he believes the response predictor analysis is a step in this direction, which might be valuable for better individualizing therapy.

The studies were funded by Chiesi Farmaceutici. Dr. Singh reports no potential conflicts of interest.

Virchow JC et al. Lancet. 2019 Sep 30. doi. org/10.1016/S0140-6736(19)32215-9.

Six factors predicted benefit from asthma triple therapy