Building the foundation for a community-generated national research blueprint for inherited bleeding disorders: research priorities for ultra-rare inherited bleeding disorders.

BACKGROUND: Ultra-rare inherited bleeding disorders (BDs) present important challenges for generating a strong evidence foundation for optimal diagnosis and management. Without disorder-appropriate treatment, affected individuals potentially face life-threatening bleeding, delayed diagnosis, suboptimal management of invasive procedures, psychosocial distress, pain, and decreased quality-of-life. RESEARCH DESIGN AND METHODS: The National Hemophilia Foundation (NHF) and the American Thrombosis and Hemostasis Network identified the priorities of people with inherited BDs and their caregivers, through extensive inclusive community consultations, to inform a blueprint for future decades of research. Multidisciplinary expert Working Group (WG) 3 distilled highly feasible transformative ultra-rare inherited BD research opportunities from the community-identified priorities. RESULTS: WG3 identified three focus areas with the potential to advance the needs of all people with ultra-rare inherited BDs and scored the feasibility, impact, and risk of priority initiatives, including 13 in systems biology and mechanistic science; 2 in clinical research, data collection, and research infrastructure; and 5 in the regulatory process for novel therapeutics and required data collection. CONCLUSIONS: Centralization and expansion of expertise and resources, flexible innovative research and regulatory approaches, and inclusion of all people with ultra-rare inherited BDs and their health care professionals will be essential to capitalize on the opportunities outlined herein.

Living with an ultra-rare inherited bleeding disorder is challenging. Patients can feel alone and unsure of where to find support because their disorder is so rare. In this paper, a group of ultra-rare bleeding disorder experts, including doctors, researchers, regulators, patient advocates, and patients, identify the research that could best improve the lives of people with these disorders. They propose a national network of specialists who can help doctors, who may never have seen these disorders before, to find the right diagnosis faster. A centralized laboratory specialized in ultra-rare bleeding disorders could also improve diagnosis and do research studies. This would help us learn, for example, how symptoms change throughout a patient's life, how effective different treatments are, and what it is like for patients to live with these disorders. A second research priority is to better understand each individual disorder so that the best treatments can be chosen or developed. A pathway showing doctors which treatment options to try, in which order, would help them help their patients. The third research priority is to make it easier to study new treatments for ultra-rare bleeding disorders. This requires designing studies with very small numbers of participants, identifying meaningful outcomes to measure, and convincing pharmaceutical companies to invest in these studies. International agreement on these requirements would allow more patients to participate and benefit from the research. These top-priority research goals should greatly improve knowledge about, and diagnosis and treatment of, ultra-rare inherited bleeding disorders.

Pharmacodynamic Activity of the Novel Neurokinin-3 Receptor Antagonist SJX-653 in Healthy Men.

CONTEXT: SJX-653 is a novel neurokinin 3 receptor (NK3R) antagonist. The NK3 pathway is a central regulator of gonadotropin releasing hormone (GnRH) secretion and has also been implicated in the generation of hot flashes. Therefore, decreases of luteinizing hormone (LH) and testosterone in men serve as sensitive pharmacodynamic (PD) markers of central NK3 antagonism. OBJECTIVE: To characterize the safety, tolerability, pharmacokinetics, and pharmacodynamic activity of SJX-653 in healthy men. DESIGN: A randomized, placebo-controlled, double-blind, single ascending dose study. SETTING: Phase 1 unit. PATIENTS OR OTHER PARTICIPANTS: Seven cohorts of 6 healthy men 18-45 years of age (4:2 randomization to SJX-653/placebo per cohort). INTERVENTION(S): Single oral doses of 0.5-90 mg SJX-653. MAIN OUTCOME MEASURE(S): Safety assessments and serial pharmacokinetic (PK)/PD measurements. RESULTS: SJX-653 was well tolerated at all dose levels. Cmax and AUC0-24 increased in a dose-proportional manner. The terminal elimination half-life ranged between 9.8 and 12.5 hours independent of dose. A statistically significant, dose-dependent, reversible reduction of LH and testosterone was observed with near maximal effect after 15 mg and little to no effect at 4.5 mg. Maximal LH reduction was 70 ±â€…7% (mean ±â€…sd) at 6 hours after 30 mg SJX-653 versus 10 ±â€…43% for placebo (P = 0.0006); maximal T reduction was of 68 ±â€…5% at 8 hours after 60 mg SJX-653 versus 18 ±â€…11% for placebo (P < 0.0001). The plasma IC50 for LH reduction was 33 ng/mL. CONCLUSIONS: These data demonstrate clinical proof-of-mechanism for SJX-653 as a potent centrally-acting NK3R antagonist.

Early treatment with alglucosidase alpha prolongs long-term survival of infants with Pompe disease.

In a previous 52-wk trial, treatment with alglucosidase alpha markedly improved cardiomyopathy, ventilatory function, and overall survival among 18 children <7 mo old with infantile-onset Pompe disease. Sixteen of the 18 patients enrolled in an extension study, where they continued to receive alglucosidase alpha at either 20 mg/kg biweekly (n = 8) or 40 mg/kg biweekly (n = 8), for up to a total of 3 y. These children continued to exhibit the benefits of alglucosidase alpha at the age of 36 mo. Cox regression analyses showed that over the entire study period, alglucosidase alpha treatment reduced the risk of death by 95%, reduced the risk of invasive ventilation or death by 91%, and reduced the risk of any type of ventilation or death by 87%, compared with an untreated historical control group. Cardiomyopathy continued to improve and 11 patients learned and sustained substantial motor skills. No significant differences in either safety or efficacy parameters were observed between the 20 and 40 mg/kg biweekly doses. Overall, long-term alglucosidase alpha treatment markedly extended survival as well as ventilation-free survival and improved cardiomyopathy.

Clinical outcomes after long-term treatment with alglucosidase alfa in infants and children with advanced Pompe disease.

PURPOSE: A clinical trial was conducted to evaluate the safety and efficacy of alglucosidase alfa in infants and children with advanced Pompe disease. METHODS: Open-label, multicenter study of IV alglucosidase alfa treatment in 21 infants 3-43 months old (median 13 months) with minimal acid alpha-glucosidase activity and abnormal left ventricular mass index by echocardiography. Patients received IV alglucosidase alfa every 2 weeks for up to 168 weeks (median 120 weeks). Survival results were compared with an untreated reference cohort. RESULTS: At study end, 71% (15/21) of patients were alive and 44% (7/16) of invasive-ventilator free patients remained so. Compared with the untreated reference cohort, alglucosidase alfa reduced the risk of death by 79% (P < 0.001) and the risk of invasive ventilation by 58% (P = 0.02). Left ventricular mass index improved or remained normal in all patients evaluated beyond 12 weeks; 62% (13/21) achieved new motor milestones. Five patients were walking independently at the end of the study and 86% (18/21) gained functional independence skills. Overall, 52% (11/21) of patients experienced infusion-associated reactions; 95% (19/20) developed IgG antibodies to recombinant human lysosomal acid alpha-glucosidase; no patients withdrew from the study because of safety concerns. CONCLUSIONS: In this population of infants with advanced disease, biweekly infusions with alglucosidase alfa prolonged survival and invasive ventilation-free survival. Treatment also improved indices of cardiomyopathy, motor skills, and functional independence.