Portopulmonary hypertension practice patterns after liver transplantation.

Portopulmonary hypertension (POPH) is a type of pulmonary arterial hypertension occurring exclusively in those with portal hypertensive liver disease. Liver transplantation (LT) can significantly improve outcomes. Current guidelines counsel against immediate adjustments to targeted therapy after LT and suggest routine echocardiography as sufficiently informative to guide therapeutic adjustments. Current practice patterns for adjusting targeted therapy after LT in POPH, and how they compare with guidelines, are not well established. To answer this question, we performed an institutional review board-approved, cross-sectional mixed-methods survey-based study of US POPH providers. Anonymized requests to complete the survey were sent through professional networks between January 20, 2022, and April 20, 2022. Responses were compared between cardiologists and pulmonologists using Fisher's exact tests, at a significance of 0.05. A total of 85 POPH physicians were included in the final analysis (66% pulmonologists and 34% cardiologists). Following LT, the majority of respondents routinely used a combination of standard cardiopulmonary assessment modalities to guide adjustment of targeted therapy following LT. Most respondents (69%) started by adjusting parenteral prostacyclins with small titrations and frequent reassessments within 3 months of LT, but some (19.7%) adjusted targeted therapy immediately after LT. Our results showed that the majority of respondents favored serial integrated cardiopulmonary testing (including routine right heart catheterization) to guide the adjustment of targeted therapy in POPH after LT, and almost one-fifth of respondents weaned therapy immediately after LT. Our study demonstrates heterogeneity in POPH practice patterns after LT, highlights differences between current practice patterns and the most recent guidelines, emphasizes the need for additional research, and supports a team-based approach to standardize care for these high-risk patients and optimize post-LT outcomes.

Efficacy of Inhaled Treprostinil on Multiple Disease Progression Events in Patients with Pulmonary Hypertension due to Parenchymal Lung Disease in the INCREASE Trial.

Rationale: The INCREASE study of inhaled treprostinil met its primary endpoint of change in 6-minute-walk distance at Week 16. In addition, there were significantly fewer clinical worsening events in patients receiving inhaled treprostinil. However, the incidence of multiple events in the same patient is unknown. Objectives: This post hoc analysis evaluated the effect of continued treatment with inhaled treprostinil on the frequency and impact of multiple disease progression events. Methods: Patients enrolled in INCREASE were analyzed for disease progression events, defined as at least 15% decline in 6-minute-walk distance, exacerbation of underlying lung disease, cardiopulmonary hospitalization, lung transplantation, at least 10% decline in forced vital capacity, or death during the duration of the 16-week study. Measurements and Main Results: In total, 147 disease progression events occurred in the inhaled treprostinil group (89/163 patients, 55%) compared with 215 events (109/163 patients, 67%) in the placebo group (P = 0.018). There was a lower incidence of each disease progression component in the inhaled treprostinil group: 6-minute-walk distance decline (45 vs. 64 events), lung disease exacerbation (48 vs. 72 events), FVC decline (19 vs. 33), cardiopulmonary hospitalization (23 vs. 33 events), and death (10 vs. 12). Fewer patients receiving inhaled treprostinil had multiple progression events compared with those receiving the placebo (35 vs. 58, 22% vs. 36%; P = 0.005). Conclusions: Patients who received inhaled treprostinil were significantly less likely to experience further disease progression events after an initial event compared with patients receiving placebo. These results support the continuation of inhaled treprostinil despite the occurrence of disease progression in clinical practice.

Struggling Between Liver Transplantation and Portopulmonary Hypertension.

Portopulmonary hypertension (PoPH) is a progressive, ultimately fatal cardiopulmonary disease that occurs exclusively in patients with underlying portal hypertensive liver disease. PoPH outcomes are driven by both the severity of underlying liver disease and the degree of cardiac adaptation to elevated pulmonary pressures. The mainstay of treatment in PoPH is targeted pulmonary vascular therapy. Liver transplantation (LT) can be beneficial in some patients, but is associated with considerable risks in the PoPH population, and outcomes are variable. The optimal management strategy for PoPH, LT, or medical therapy alone, is unclear, and further research is needed to help guide clinical decision-making.

Predictive value of incidental right ventricular abnormalities identified on SPECT for mortality and pulmonary hypertension.

BACKGROUND: The clinical significance of incidentally found RV abnormalities on low-risk SPECT studies is not well-defined. The objective of this study was to determine the predictive value of incidental right ventricular (RV) abnormalities identified on single photon emission computed tomography (SPECT) scans for mortality and pulmonary hypertension (PH). METHODS: We retrospectively analyzed all low-risk SPECT studies in patients without known coronary artery or pulmonary vascular disease, performed at our institution, from 2007-2020. Adjusted Cox proportional hazards models were used to evaluate the association between incidental RV abnormalities on low-risk SPECT studies and outcomes. RESULTS: Of the 4761 patients included in the analysis, mortality events were present in 494, and echocardiographic PH was present in 619. Incidental RV abnormalities on low-risk SPECT studies were significantly and independently associated with all-cause mortality (HR = 1.41, CI [1.07-1.86], P = 0.0152) and echocardiographic PH (HR = 2.06, CI [1.64-2.60], P < 0.0001). CONCLUSIONS: These data suggest incidental RV abnormalities found on low-risk SPECT imaging studies are significantly and independently associated with increased mortality and risk of developing echocardiographic PH, and could identify high-risk patients for closer monitoring and additional diagnostic testing.

Pulmonary Vascular Resistance Predicts Mortality and Graft Failure in Transplantation Patients With Portopulmonary Hypertension.

Portopulmonary hypertension (POPH) is a pulmonary vascular disease associated with significant morbidity and mortality in those with liver disease, conferring a higher mortality in patients awaiting liver transplantation (LT). Although not a transplant indication, patients with POPH can experience significant clinical improvement following LT, and those maintaining a mean pulmonary artery pressure (MPAP) <35mm Hg and a pulmonary vascular resistance (PVR) <5 Woods units (WU) are granted additional listing points to expedite LT. The effect of POPH on posttransplant outcomes such as mortality and graft failure, however, is not well defined. We performed a retrospective cohort study of the US Organ Procurement and Transplantation Network database of all adult patients who underwent LT between January 1, 2006, and December 1, 2020. Using adjusted accelerated failure time models, we examined the relationship between a diagnosis of POPH and outcomes following LT and the relationship between pre-LT hemodynamics and post-LT survival (alive with a functioning graft) in patients with POPH. Compared with those undergoing transplants without exception points, patients with POPH had comparable post-LT survival rates but were significantly more likely to have graft failure. Both pre-LT MPAP and PVR predicted post-LT survival in POPH, with a pre-LT PVR of ≥1.6 WU, more than doubling the hazard for mortality (death or a nonfunctioning graft; coefficient, 2.01; standard error, 0.85; hazard ratio, 2.21; P = 0.02). POPH may confer a significantly higher risk of post-LT graft failure compared with patients with cirrhosis without POPH, and a pre-LT PVR of ≥1.6 WU may predict post-LT survival. Further investigation into the relationship between pre-LT hemodynamics, right ventricular function, and post-LT outcomes of mortality and graft failure in POPH is needed.

An expert panel delphi consensus statement on patient selection and management for transitioning between oral and inhaled treprostinil.

Treprostinil, a prostacyclin analogue used in the treatment of pulmonary arterial hypertension (PAH), is available for administration by parenteral, oral, or inhaled routes. Transitioning between routes may be beneficial for appropriate patients; however, there is little published data on transitions between oral and inhaled treprostinil. We used a modified Delphi process to develop expert consensus recommendations on transitions between these formulations. Three questionnaires were used to develop statements about relevant aspects of transition management, which the panelists rated, using a Likert scale, from -5 (strongly disagree) to +5 (strongly agree). Eleven physicians with expertise in PAH treatment modalities, participated in the panel. Of the 492 statements evaluated, consensus was reached on 215 (43.7%). Key consensus recommendations included (1) accurately defining successful transition, as stable or improved PAH with good tolerability and adherence, and (2) patients with stable, low-risk PAH showing insufficient response or tolerability to their existing treprostinil therapy (and due to restrictions in up titration of dosing), as appropriate candidates for transitions between treprostinil formulations. Panelists did not reach consensus for an overall strategy for performing these transitions, mainly because of variability in their practice parameters. Consensus was also achieved on recommendations for adverse event management, including reassurance, administration of oral treprostinil 3 times daily with food, and dosing inhaled treprostinil at intervals ≥3 hours apart. The Delphi process aided in developing expert consensus recommendations that may provide clinically useful guidance for transitioning between treprostinil formulations. However, additional data from centers with high volumes of PAH patients undergoing treprostinil transitions would be optimal for defining more complete and robust strategies to facilitate successful transition.

Association of Borderline Pulmonary Hypertension With Mortality and Hospitalization in a Large Patient Cohort: Insights From the Veterans Affairs Clinical Assessment, Reporting, and Tracking Program.

BACKGROUND: Pulmonary hypertension (PH) is associated with increased morbidity across the cardiopulmonary disease spectrum. Based primarily on expert consensus opinion, PH is defined by a mean pulmonary artery pressure (mPAP) ≥25 mm Hg. Although mPAP levels below this threshold are common among populations at risk for PH, the relevance of mPAP <25 mm Hg to clinical outcome is unknown. METHODS AND RESULTS: We analyzed retrospectively all US veterans undergoing right heart catheterization (2007-2012) in the Veterans Affairs healthcare system (n=21,727; 908-day median follow-up). Cox proportional hazards models were used to evaluate the association between mPAP and outcomes of all-cause mortality and hospitalization, adjusted for clinical covariates. When treating mPAP as a continuous variable, the mortality hazard increased beginning at 19 mm Hg (hazard ratio [HR]=1.183; 95% confidence interval [CI], 1.004-1.393) relative to 10 mm Hg. Therefore, patients were stratified into 3 groups: (1) referent (≤18 mm Hg; n=4,207); (2) borderline PH (19-24 mm Hg; n=5,030); and (3) PH (≥25 mm Hg; n=12,490). The adjusted mortality hazard was increased for borderline PH (HR=1.23; 95% CI, 1.12-1.36; P<0.0001) and PH (HR=2.16; 95% CI, 1.96-2.38; P<0.0001) compared with the referent group. The adjusted hazard for hospitalization was also increased in borderline PH (HR=1.07; 95% CI, 1.01-1.12; P=0.0149) and PH (HR=1.15; 95% CI, 1.09-1.22; P<0.0001). The borderline PH cohort remained at increased risk for mortality after excluding the following high-risk subgroups: (1) patients with pulmonary artery wedge pressure >15 mm Hg; (2) pulmonary vascular resistance ≥3.0 Wood units; or (3) inpatient status at the time of right heart catheterization. CONCLUSIONS: These data illustrate a continuum of risk according to mPAP level and that borderline PH is associated with increased mortality and hospitalization. Future investigations are needed to test the generalizability of our findings to other populations and study the effect of treatment on outcome in borderline PH.

Worsening gradient of aortic stenosis with treatment of pulmonary arterial hypertension in scleroderma.

Systemic sclerosis (SSc) can cause interstitial lung and pulmonary vascular disease that can induce pulmonary arterial hypertension (PAH). It is well known that severe PAH may reduce left ventricluar preload and decrease diastolic filling with the potential of reducing forward flow. We present a case in which a patient with SSc and symptomatic PAH required direct pulmonary vasodilator therapy for treatment of elevated pulmonary pressures. On follow-up echocardiogram, while improvement in right ventricular function and reduction in estimated pulmonary pressures were noted; worsening of aortic valve gradients was also found. Cardiac hemodynamics of pulmonary vasodilator therapy is discussed and the literature is reviewed.

Objective measures of right ventricular function during exercise: results of a pilot study.

BACKGROUND: A growing body of evidence seems to suggest that reduction in right ventricular (RV) systolic function is not only associated with both development of symptoms associated with pulmonary arterial hypertension (PAH) but also increased morbidity and adverse clinical outcomes. Recent data suggest that supine bicycle stress echocardiography (sBEE) is feasible and provides realistic resistance and compliance estimations. METHODS: The study design was a retrospective analysis of sBEE obtained for clinical indications of dyspnea on exertion or unexplained exercise intolerance. A total of 30 sBEE studies were included. The first 10 sBEE studies served as a calibration cohort not only to establish objective measures of RV performance but also to determine feasibility and reproducibility. The following 20 sBEE served as a validation cohort. RESULTS: Our results demonstrate that tricuspid annular plane systolic excursion and tricuspid annular systolic velocity, even when measured by an untrained reader, are reliable and accurate measures of the RV response to exercise during a sBEE protocol. Furthermore, measurements of RV myocardial performance (Tei index) or peak RV strain during exercise not only are time consuming but also simply unreliable and should not be utilized to evaluate RV function during sBEE. CONCLUSION: The results of our pilot study suggest that sBEE might be promising for detecting RV abnormalities during exercise. A larger prospective study is now needed to determine if TAPSE and tricuspid annular systolic velocity recorded during sBEE might be useful in assessing patients presenting with dyspnea during exercise or suspected of having PAH.

Right ventricular ejection efficiency: a new echocardiographic measure of mechanical performance in chronic pulmonary hypertension.

BACKGROUND: The severity of pulmonary vascular resistance (PVR) is known to be a critical determinant of right ventricular (RV) systolic function; this relationship remains poorly characterized. We therefore, designed a study to examine the relationship that exists between echocardiographically measured PVR and maximal tricuspid annular plane systolic excursion (TAPSE) to gain some insight regarding RV ejection efficiency (RVEe) in patients with chronic pulmonary hypertension (cPH). METHODS: Standard echocardiographic measures of RV size and systolic performance were recorded from 95 patients (age 54 ± 15 years and pulmonary artery systolic pressures [PASP] that range from 20 to 125 mmHg). For this study, RVEe was defined as TAPSE/Echocardiographic PVR. RESULTS: A strong negative correlation (R(2) = -0.51, P < 0.001) was seen between TAPSE and PASP; however, a power curve trend line fit the relationship between RVEe and PASP (R(2) = 0.77; P < 0.01). In a multiple regression analysis, abnormal pulmonary pressures were better identified when RVEe (P < 0.0001) was used. CONCLUSIONS: Based on these results, it appears that measurement of RVEe might be extremely useful for the assessment of RV mechanics and plasticity. The power curve relationship clearly demonstrates that minimal changes in PASP (up to 50 mmHg) result in dramatic reductions in RVEe. A steady decline in RVEe, though at a lower rate, continues to occur with increasing PASP. Additional studies are required using RVEe into a functional RV imaging algorithm and determine if RVEe correlates with development of symptoms, response to therapy and overall clinical outcomes.

Association of Cardiopulmonary Hemodynamics and Mortality in Veterans With Liver Cirrhosis: A Retrospective Cohort Study.

BACKGROUND: Portopulmonary hypertension (PoPH), associated with increased mortality, can limit treatment options for liver diseases. Data on the continuum of clinical risk related to cardiopulmonary hemodynamics in PoPH are lacking. METHODS AND RESULTS: As part of the United States national Veterans Affairs Clinical Assessment, Reporting, and Tracking database, we performed a retrospective cohort study of adults with cirrhosis undergoing right heart catheterization between October 1, 2017, and September 30, 2022. Pulmonary hypertension (mean pulmonary arterial pressure [mPAP] >20 mm Hg without PoPH) and PoPH (mPAP >20 mm Hg+pulmonary artery wedge pressure ≤15 mm Hg+pulmonary vascular resistance ≥3 WU) were defined by right heart catheterization hemodynamics. Multivariable Cox proportional hazards using natural splines for hemodynamic variables were used to evaluate the association between cardiopulmonary hemodynamics and mortality following right heart catheterization. A total of 4409 patients were included in the final analysis, predominantly men (96.3%), with a mean age of 68.5 years. Pulmonary hypertension and PoPH were observed in 71.6% and 10.2% of the cohort, respectively. Compared with a reference cardiac index of 2.5 L/min per m2, the hazard for mortality increased progressively with decreasing cardiac index, even after adjustment for mPAP and pulmonary vascular resistance. The minority of patients with PoPH (N=65, 14.5%) were prescribed pulmonary vasodilator therapy. CONCLUSIONS: These data suggest that pulmonary hypertension and PoPH are prevalent in veterans with chronic liver disease, but low use of targeted PoPH therapy persists. Cardiac function discriminated mortality risk across a wide range of mPAP and pulmonary vascular resistance values and may diagnose and clarify prognosis in this patient population.

Oral Treprostinil is Associated with Improved Survival in FREEDOM-EV and its Open-Label Extension.

INTRODUCTION: In the event-driven FREEDOM-EV trial, oral treprostinil delayed clinical worsening in patients with pulmonary arterial hypertension (PAH). Open-label extension studies offer additional data about tolerability, efficacy, and survival, especially for those initially assigned placebo. The aim of the current study was to determine if oral treprostinil changed survival when considering the parent and extension study, if treprostinil provides functional benefits for participants initially assigned to placebo, and if the benefits observed for those treated with treprostinil were durable. METHODS: Both active and placebo participants from FREEDOM-EV could enroll in the FREEDOM-EV open-label extension (OLE) study after experiencing an investigator-assessed clinical worsening event or after parent study closure. All participants in the OLE were offered open-label oral treprostinil. Previously assigned placebo participants titrated to maximally tolerated doses; previously assigned treprostinil participants continued dose titration. We repeated assessments including functional class and 6-min walk distance (6MWD) at 12-week intervals and measured N-terminal pro-brain natriuretic peptide (NT-proBNP) at week 48. Survival was estimated by Kaplan-Meier analysis, and we estimated hazard ratio (HR) using Cox proportional hazards. RESULTS: Of 690 FREEDOM-EV participants, 470 enrolled in the OLE; vital status was available for 89% of initial Freedom-EV participants. When considering the combined parent and open-label data, initial assignment to oral treprostinil reduced mortality (HR 0.64, 95% confidence interval 0.46-0.91, p = 0.013); absolute risk reduction was 9%. Participants randomized to placebo who initiated oral treprostinil after clinical worsening and tolerated treatment through week 48 demonstrated favorable shifts in functional class (p < 0.0001), 6MWD improvements of + 84 m (p < 0.0001), and a reduction in NT-proBNP of - 778 pg/mL (p = 0.02), compared to OLE baseline. Modest trends toward benefit were measured for those initially assigned placebo who did not have clinical worsening, and 132/144 (92%) of treprostinil assigned participants without clinical worsening remained on drug at week 48 in the OLE study. Adverse events were consistent with FREEDOM-EV. CONCLUSION: Initial treprostinil assignment improved survival in the entire data set; those who began treprostinil after a clinical worsening in the placebo arm and tolerated drug to week 48 enjoyed substantial functional gains. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT01560637.

Expert provider survey of longitudinal assessment in patients with pulmonary arterial hypertension.

BACKGROUND: Patients suffering from pulmonary arterial hypertension (PAH) demand frequent assessment to keep pace with a dynamic and sometimes rapidly progressive disease course. To improve our understanding of patient monitoring, we conducted a survey of pulmonary hypertension (PH) providers to establish real-world practice patterns. OBJECTIVE: To evaluate the type and frequency of patient assessment methods employed by expert PH providers following PAH diagnosis METHODS: A descriptive cross-sectional survey of PH providers across the United States was utilized to assess provider practices. Between September 14, 2017 to October 17, 2017, a survey was distributed electronically to PH experts assessing follow-up frequency and testing evaluation of patients with PAH. RESULTS: 40 (11.4%) providers completed the survey, representing cardiologists, pulmonologists, and advanced practice providers at centers who cared for an average of 95 patients per year with PAH. Follow-up testing and clinic evaluation was influenced by severity of patient illness. Frequency of re-assessment of clinic follow-up, six-minute walk test, echocardiogram, brain natriuretic peptide, and right heart catheterization in various clinical scenarios all reflected disparate practice. CONCLUSIONS: Current clinical practice patterns in the monitoring of patients with PAH are variable and do not necessarily reflect guideline-based practices, suggesting the need for further research and improved guidelines on the frequency of follow up and repeat testing.

Human liver single nuclear RNA sequencing implicates BMPR2, GDF15, arginine, and estrogen in portopulmonary hypertension.

Portopulmonary hypertension (PoPH) is a type of pulmonary vascular disease due to portal hypertension that exhibits high morbidity and mortality. The mechanisms driving disease are unknown, and transcriptional characteristics unique to the PoPH liver remain unexplored. Here, we apply single nuclear RNA sequencing to compare cirrhotic livers from patients with and without PoPH. We identify characteristics unique to PoPH in cells surrounding the central hepatic vein, including increased growth differentiation factor signaling, enrichment of the arginine biosynthesis pathway, and differential expression of the bone morphogenic protein type II receptor and estrogen receptor type I genes. These results provide insight into the transcriptomic characteristics of the PoPH liver and mechanisms by which PoPH cellular dysfunction might contribute to pulmonary vascular remodeling.

Gaps in the Care of Pulmonary Hypertension: A Cross-Sectional Patient Simulation Study Among Practicing Cardiologists and Pulmonologists.

Background Diagnosis of pulmonary hypertension (PH) is often delayed or missed, leading to disease progression and missed treatment opportunities. In this study, we measured variation in care provided by board-certified cardiologists and pulmonologists in simulated patients with potentially undiagnosed PH. Methods and Results In a cross-sectional study (https://www.clinicaltrials.gov, NCT04693793), 219 US practicing cardiologists and pulmonologists cared for simulated patients presenting with symptoms of chronic dyspnea and associated signs of potential PH. We scored the clinical quality-of-care decisions made in a clinical encounter against predetermined evidence-based criteria. Overall, quality-of-care scores ranged from 18% to 74%, averaging 43.2%±11.5%. PH, when present, was correctly suspected 49.1% of the time. Conversely, physicians incorrectly identified PH in 53.7% of non-PH cases. Physicians ordered 2-dimensional echocardiography in just 64.3% of cases overall. Physicians who ordered 2-dimensional echocardiography in the PH cases were significantly more likely to get the presumptive diagnosis (61.9% versus 30.7%; P<0.001). Ordering other diagnostic work-up items showed similar results for ventilation/perfusion scan (81.5% versus 51.4%; P=0.005) and high-resolution computed tomography (60.4% versus 43.2%; P=0.001). Physicians who correctly identified PH were significantly more likely to order confirmatory right heart catheterization or refer to PH center (67.3% versus 15.8%; P<0.001). Conclusions A wide range of care in the clinical practice among simulated patients presenting with possible PH was found, specifically in the evaluation and plan for definitive diagnosis of patients with PH. The delay or misdiagnosis of PH is likely attributed to a low clinical suspicion, nonspecific symptoms, and underuse of key diagnostic tests. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT04693793.

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: gov.

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.

Implementing the EXPEDITE parenteral induction protocol: Rapid parenteral treprostinil titration and transition to oral treprostinil.

Treprostinil is a prostacyclin analogue that targets multiple cellular receptors to treat pulmonary arterial hypertension (PAH). In certain scenarios, patients may require aggressive treprostinil titration. Several studies have demonstrated that higher doses of treprostinil lead to greater clinical benefit. Data supports successful transitions from parenteral to oral treprostinil; however, administration routes, transition duration, and transition setting vary in the real-world. The EXPEDITE clinical trial (NCT03497689) prospectively studied whether rapid parenteral treprostinil induction can be used to achieve high doses of oral treprostinil (total daily dose: ≥12 mg) in prostacyclin naïve PAH patients. Parenteral prostacyclin induction may be more appropriate for patients who need to reach therapeutic dosing more urgently than longer titration durations reported with conventional de novo oral treprostinil initiation. This summary provides strategies utilized in EXPEDITE. Parenteral treprostinil was initiated at 2 ng/kg/min intravenously or subcutaneously; clinicians determined the frequency and dose increment of up-titration. Two distinct transition schedules from parenteral to oral treprostinil were employed: rapid cross-titration in an inpatient setting (median: 2 days) or gradual cross-titration in an outpatient setting (median: 5 days). Patient status was closely monitored after transition; oral treprostinil dose was titrated to clinical effect and tolerability. Factors considered when individualizing dosing strategies included parenteral and oral treprostinil target doses, nursing support, patient education, medication counseling and adverse events management. EXPEDITE demonstrated the time to a therapeutic dose of oral treprostinil is significantly shorter when utilizing a short-term parenteral induction strategy and may be suitable for patients requiring aggressive titration of oral treprostinil.