Survival and drug persistence in patients receiving inhaled treprostinil at doses greater than 54 µg (nine breaths) four times daily

Parenteral treprostinil induction for rapid attainment of therapeutic doses of oral treprostinil

RATIONALE

Oral treprostinil slows disease progression and improves exercise capacity in pulmonary arterial hypertension; however, titration can be prolonged. Published data suggests prostacyclin-naïve patients achieve total daily oral treprostinil doses of about 6 mg by Week 16, while those on prior parenteral treprostinil reach higher doses at the same timepoint.

OBJECTIVES

EXPEDITE (NCT03497689), a single-arm, multicenter study, assessed the efficacy of rapid parenteral treprostinil induction to quickly reach higher doses of oral treprostinil for the treatment of pulmonary arterial hypertension.

METHODS

Parenteral treprostinil was titrated for 2-8 weeks, followed by cross-titration of oral treprostinil. The primary endpoint was percentage of patients reaching ≥12 mg daily of oral treprostinil at Week 16. Secondary endpoints included clinical changes from baseline to Week 16.

RESULTS

Twenty-nine prostacyclin-naïve patients were included in efficacy analyses. At Week 16, the mean daily oral treprostinil dose was 16.4 mg; 79% of patients met the primary endpoint. From baseline to Week 16, median REVEAL Lite 2 score improved (decreased) from 6 to 3.5 (p = 0.0006). Statistically significant improvements were also seen in World Health Organization Functional Class, N-terminal-pro brain natriuretic peptide levels, 6-minute walk distance, right atrial area, Borg Dyspnea Score, and emPHasis-10 score. Favorable trends were seen in risk stratification, echocardiography parameters, disease symptoms, and treatment satisfaction.

CONCLUSION

Short-course parenteral treprostinil induction resulted in oral treprostinil doses over twice those reported in de novo initiations and may be a useful approach to quickly achieve the therapeutic benefits of oral treprostinil.

Pulmonary hypertension inhaled therapies: An updated review

Treatments of pulmonary hypertension (PH) continue to evolve with approval of new therapies. The currently FDA approved inhaled PH therapies include inhaled iloprost for group 1 pulmonary arterial hypertension (PAH), inhaled treprostinil solution and treprostinil dry powder inhaler for both group 1 PAH and group 3 PH associated with interstitial lung disease (PH-ILD). Inhaled treprostinil was recently approved for group 3 PH-ILD based on the results of INCREASE trial and the newer formulation of treprostinil dry powder that comes with a new inhaler was recently approved for both group 1 PAH and group 3 PH-ILD based on BREEZE study. The pipeline for inhaled PH therapies includes several promising molecules that can enrich the current PH therapeutic era and mitigate several systemic side effects by directly delivering the drug to the target organ. In this review article we summarize the evidence for the currently approved inhaled PAH/PH therapies, discuss the available inhalation devices, present a roadmap for successful treatment strategy, and present several inhaled PAH/PH therapies in the pipeline.

Inhaled Treprostinil Dosage in Pulmonary Hypertension Associated With Interstitial Lung Disease and Its Effects on Clinical Outcomes

BACKGROUND

Pulmonary hypertension (PH) complicates the course of many patients with fibrotic interstitial lung disease (ILD). Inhaled treprostinil (iTre) has been shown to improve functional ability and to delay clinical worsening in patients with PH resulting from ILD.

RESEARCH QUESTION

Do higher dosages of iTre have greater benefits in preventing clinical worsening and achieving clinical improvement?

STUDY DESIGN AND METHODS

Post hoc analysis of the INCREASE study, a 16-week double-blind, randomized, placebo-controlled trial of iTre in patients with PH resulting from ILD. Four groups were identified based on the number of breaths per session (bps; < 9 and ≥ 9 bps) of active drug or placebo attained at 4 weeks. Patients were evaluated for clinical worsening (15% decrease in 6-min walkdistance, cardiopulmonary hospitalization, lung transplantation, or death) or clinical improvement (15% increase in the six-minute walk distance with a concomitant 30% reduction in N-terminal prohormone of brain natriuretic peptide without any clinical worsening event).

RESULTS

At 4 weeks, 70 patients were at a dose of ≥ 9 bps (high-dosage group) and 79 patients were at a dose of < 9 bps (low-dosage group) in the iTre arm vs 86 patients in the high-dose group and 67 patients in the low-dose group in the placebo arm. Between weeks 4 and 16, 17.1% of patients in the high-dose treprostinil group and 22.8% in the low-dose treatment group experienced a clinical worsening event vs 33.7% and 34.3% of patients in the two placebo arms, respectively (P = .006). By week 16, 15.7% and 12.7% of patients in the high- and low-dose iTre groups, respectively, demonstrated clinical improvement vs 7% and 1.5% patients in the placebo arms (P = .003) INTERPRETATION: Higher dosages of iTre overall show greater benefit in terms of preventing clinical worsening and achieving clinical improvement. These data support the early initiation and uptitration of therapy to a dosage of at least 9 bps four times daily in patients with PH resulting from ILD.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT02630316; URL: www.

CLINICALTRIALS

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