Rodriguez‐Lopez, Josanna

Abstract Hereditary hemorrhagic telangiectasia (HHT), an autosomal dominant vasculopathy affecting 1 in 5000 individuals, is the second most common inherited bleeding disorder worldwide. Despite this prevalence, comprehensive data on disease manifestations and complications remain limited. To address this gap, the US Congress allocated funding leading to the Comprehensive HHT Outcomes Registry of the United States (CHORUS), a prospective, 15-center longitudinal registry enrolling unselected patients with confirmed HHT. In this initial report, we describe findings from the first 600 participants, with a median age of 53 (range, 0-88) years and 60% female. Despite most participants developing typical HHT manifestations by age 13 years, the majority (63%) were not diagnosed until mid-to-late adulthood. Recurrent spontaneous epistaxis occurred in 95% of participants, chronic gastrointestinal bleeding in 30%, and heavy menstrual bleeding in 35% of postmenarche females, together resulting in moderate-to-severe mucosal bleeding in 76%. Iron deficiency and/or anemia were diagnosed in 68%, with 41% requiring IV iron and 25% requiring red cell transfusions. Serious complications of solid-organ arteriovenous malformations were frequent, including intracranial hemorrhage (3%), pulmonary hemorrhage (2%), venous thromboembolism (7%), arterial thromboembolism (11%), heart failure (7%), and pulmonary hypertension (7%). These data from CHORUS, the first national US registry of its kind, provide reliable, real-world estimates of the incidence, prevalence, and severity of numerous HHT manifestations and complications. HHT has a high burden of moderate-to-severe bleeding, anemia, thrombosis, and major neurologic and cardiopulmonary complications. There is a mean interval between first symptoms and diagnosis of >2 decades, during which substantial, serious, and preventable HHT morbidity, including early intracranial hemorrhage, may occur. This trial was registered at clinicaltrials.gov as NCT06259292.

Abstract Hereditary hemorrhagic telangiectasia (HHT) causes severe recurrent epistaxis, chronic gastrointestinal bleeding, solid organ arteriovenous malformations, and significant anemia. Although it is the second most common inherited bleeding disorder worldwide, no approved therapies exist. The multicenter, US randomized, controlled PATH-HHT trial demonstrated efficacy of short-term pomalidomide treatment of epistaxis in HHT. However, questions regarding long-term safety, effectiveness, and utility for HHT-associated gastrointestinal bleeding remain. The PATH-HHT ATLAS (after trial longitudinal assessment study) was a multicenter US longitudinal observational study evaluating patients enrolled in PATH-HHT who continued pomalidomide after PATH-HHT through a poststudy drug access program, with ongoing close monitoring per PATH-HHT protocol and as mandated by the US Food and Drug Administration. Sixty-two patients treated with pomalidomide for HHT for up to 4.4 years were included. Significant, durable improvements in mean epistaxis severity score (5.55 points [baseline] to 2.80 points [month 12]; P< .0001) and mean hematologic support score (9.11 red cell unit equivalents [RUEs] during 6 months pretreatment to 5.73 RUEs [months 7-12]; P = .0056) were observed. Pomalidomide was less effective for gastrointestinal bleeding than for epistaxis, particularly in patients with high red blood cell transfusion requirements. Thirty-one patients (50%) underwent dose reduction from 4 mg daily, primarily due to neutropenia, but most maintained effectiveness at 2 or 3 mg daily. Over 105.2 patient-years of pomalidomide treatment, 0 patients developed peripheral neuropathy, 1 developed venous thromboembolism, and 5 developed serious infections. In conclusion, pomalidomide was effective for HHT-associated epistaxis over extended durations, albeit with nontrivial potential toxicities, and may be considered for certain patients with HHT. This trial was registered at www.clinicaltrials.gov as NCT07018401.

Abstract BACKGROUND Hereditary hemorrhagic telangiectasia (HHT) is the second most common inherited bleeding disorder (IBD) worldwide, afflicting 1 in 5,000 people. HHT is likely the most morbid IBD of women. Severe, recurrent epistaxis, gastrointestinal (GI) bleeding, and solid organ arteriovenous malformations (AVMs) cause major clinical and psychosocial morbidity and reduced survival. In recognition of the serious morbidity of HHT as an IBD, in 2022 the U.S. Congress allocated funding to create CHORUS, the Comprehensive HHT Outcomes Registry of the United States (NCT06259292). Herein, we present the initial report from CHORUS. METHODS CHORUS is a prospective, multicenter, U.S. longitudinal registry enrolling unselected patients with HHT, collecting over 2400 data elements. Data were collected by trained research coordinators at enrollment and follow-up visits via the medical record and direct participant interviews. RESULTS Patients. 600 patients with genetically- or Curacao criteria-confirmed HHT were enrolled from November 2023 to April 2025 at 15 U.S. HHT Centers of Excellence. Median (range) age was 53 (0-88) years, and the cohort was 60% female. Despite most patients developing typical HHT disease manifestations by age 13, most HHT diagnoses (63%) were made during mid-to-late adulthood. Mucosal Bleeding. 568 patients (95%) developed recurrent spontaneous epistaxis, with 339 (60%) developing recurrent epistaxis prior to age 13; 43% had at least one nasal surgery/procedure and 22% had at least one medical therapy (e.g., antifibrinolytic or antiangiogenic) for epistaxis. 180 (30%) had a known diagnosis of chronic GI bleeding. Among post-menarche females, 124 (34%) had been diagnosed with heavy menstrual bleeding. 247 (41%) reported other clinically significant mucocutaneous oral or skin bleeding. 454 (76%) had developed moderate-to-severe HHT-associated mucocutaneous bleeding, defined as an Epistaxis Severity Score >4, bleeding requiring targeted pharmaceutical or surgical intervention, IV iron, and/or red cell transfusion. This includes 334 (56%) with moderate-to-severe HHT-associated epistaxis. CNS and Pulmonary Hemorrhage. 16 patients (3%) suffered one or more intracranial hemorrhages (ICH), with 10 (63%) suffering a first ICH by age 25. 13 (2%) suffered one or more pulmonary hemorrhages. Iron Deficiency and Anemia. 408 patients (68%) had been diagnosed with anemia (351, 59%) or iron deficiency (381, 64%). Of those, 247 (61%) and 150 (37%) required IV iron and RBC transfusion, respectively. Solid Organ AVMs. Brain, pulmonary, and liver AVMs were diagnosed in 81 (15%), 268 (45%), and 128 patients (21%), respectively. Just 30 with brain AVMs (37%) had these diagnosed by age 25. 3 patients (2%) had undergone liver transplantation. Thrombosis. Venous and arterial thromboembolism occurred in 44 (7%) and 38 patients (6%), respectively, including 34 (6%) with ischemic stroke (94% of whom had pulmonary AVMs). Other Serious HHT Complications. These included heart failure in 41 patients (7%), pulmonary hypertension in 44 (7%), chronic liver disease in 17 (2.8%), epilepsy in 24 (4%), severe bacterial/deep-seated tissue infection in 35 (6%), and brain abscess in 15 (3%). 205 (34%) developed migraine. Notably, serious CNS manifestations of HHT (brain AVM, ischemic stroke, intracranial hemorrhage, and/or epilepsy) occurred in 128 (21%). 241 (40%) required emergency room visits and/or hospital admissions specifically to manage HHT complications. CONCLUSIONS This first-of-its-kind HHT registry reliably describes for the first time the incidence and severity of numerous HHT complications. Most patients develop moderate-to-severe recurrent epistaxis and/or chronic GI bleeding as well as iron deficiency anemia (usually requiring IV iron and/or RBC transfusion). Heavy menstrual bleeding, thromboembolism, severe cardiopulmonary complications, and serious CNS complications are all substantially more common in HHT than previously thought. Notably, ICH occurred in 3% of patients, which approximates the ICH incidence of hemophilia in the pre-factor prophylaxis era and is ~2-fold and ~9-fold higher than in hemophilia A treated with modern factor prophylaxis (1.6%) and modern non-factor prophylactic agents (0.3%), respectively, per the ATHN registry. This 3% number may be an underestimation given the known high ICH mortality rate, pervasive delay in HHT diagnosis, and the fact that survival post-ICH is necessary to enroll in CHORUS.

AbstractMacitentan is an oral endothelin receptor antagonist for the management of pulmonary arterial hypertension (PAH). The OPsumit® USers Registry (OPUS) and the OPsumit® Historical USers cohort (OrPHeUS) medical chart review provide real‐world data for patients newly initiating macitentan. This study aims to describe the characteristics, safety profile, and clinical outcomes of PAH patients newly treated with macitentan in the combined OPUS/OrPHeUS data set. OPUS was a prospective, multicenter, long‐term, observational drug registry from April 2014 to June 2020. OrPHeUS was a retrospective, US, multicenter chart review: observation period October 2013 to March 2017. All analyses were descriptive. At registry closure in June 2020, the combined population consisted of 5654 patients, of whom 81.9% were diagnosed with PAH. For these 4626 patients, median duration of macitentan exposure observed was 14.5 (Q1 = 5.2, Q3 = 29.0) months; idiopathic PAH (54.8%) was the most common form of PAH; macitentan was initiated as monotherapy (37.9%), or as part of double (48.0%) or triple therapy (14.1%); discontinuation due to nonhepatic/hepatic adverse events occurred in 17.1%/0.3% of patients; 9.9% of patients experienced ≥1 hepatic adverse events; Kaplan–Meier estimates showed that at 1 year 59.9% (95% confidence interval: 58.3, 61.5) of patients were free from hospitalization and survival was 90.4% (89.3, 91.3). This analysis of real‐world data from the combined OPUS and OrPHeUS populations demonstrated that macitentan is well tolerated in a large, diverse population of PAH patients, with overall and hepatic safety profiles consistent with previous macitentan clinical trials.