and was associated with some additional clinical benefits, according to a new study published in the New England Journal of Medicine.
To investigate treprostinil therapy for pulmonary hypertension in this subset of patients with lung disease, Aaron Waxman, MD, PhD, of Brigham and Women’s Hospital in Boston, and his fellow researchers launched the multicenter, randomized, double-blind, placebo-controlled INCREASE trial. They assigned 163 patients to the inhaled treprostinil group – administered via an ultrasonic, pulsed-delivery nebulizer over 16 weeks – and 163 patients to the placebo group. Their average age was 66.5 years, 73% were white, and 47% were female
At baseline, the mean 6-minute walk distance (6MWD) for all patients was 259.6 m. After 16 weeks, the treprostinil group gained a mean of 21.08 m in 6MWD, and the placebo group lost 10.04 m. The least-squares mean difference between the groups from baseline in the 6MWD was 31.12 m (95% confidence interval, 16.85-45.39; P < .001). After sensitivity analysis with multiple imputation, the difference remained significant at 30.97 m (95% CI, 16.53-45.41; P < .001).
In a comparison of N-terminal pro–B-type natriuretic peptide (NT-proBNP) levels from baseline to 16 weeks, the treprostinil group saw a decrease of 15% while the placebo group’s levels increased by 46% (treatment ratio 0.58; 95% CI, 0.47-0.72; P < .001). Clinical worsening occurred in 37 patients (23%) in the treprostinil group and 54 patients (33%) in the placebo group (hazard ratio, 0.61; 95% CI, 0.40-0.92; P = .04), while serious adverse events occurred in 23.3% of the patients on treprostinil and 25.8% of the patients on placebo. There was no significant difference between groups in patient-reported quality of life, as assessed via the St. George’s Respiratory Questionnaire.
“There was no guarantee that this was going to work in this condition,” said Adriano Tonelli, MD, of the department of pulmonary medicine at the Cleveland Clinic, in an interview. “Several small studies have tried different medications, for pulmonary hypertension or otherwise, in patients with interstitial lung disease with minimal effect, if any. Given that all the prior studies were not categorically positive, the expectation, at least on my end, was that we needed to wait and see.” Dr. Tonelli and coauthors published a post hoc analysis of inhaled treprostinil studied in the TRIUMPH and BEAT trials.
Next steps: Assess clinical outcomes after inhaled treprostinil
Although the results of this study by Waxman et al, are encouraging, and the need for a treatment in this type of pulmonary hypertension is very real, more narrowing down will be needed to confirm the benefits of inhaled treprostinil, wrote Darren B. Taichman, MD, PhD, of the University of Pennsylvania in an accompanying editorial. He wrote, “After all, patients and physicians may reason, ‘It can’t hurt.’ Unfortunately, however, it could. Therapies approved for pulmonary arterial hypertension have been studied in patients with [ILD]-associated pulmonary hypertension and have shown inconsistent results, with some studies showing no benefit or suggesting harm.”