Safety, tolerability, and pharmacokinetics of a single orally inhaled dose of PUR3100, a dry powder formulation of dihydroergotamine versus intravenous dihydroergotamine: A Phase 1 randomized, double-blind study in healthy adults.

BACKGROUND: Intravenous dihydroergotamine (DHE) has well-established efficacy for the acute treatment of migraine, but its use is limited by the need for in-hospital administration and the nausea/vomiting associated with a high maximum plasma concentration (Cmax). Inhalation is an alternative to intravenous dosing. The surface area of the lung allows for rapid absorption of a self-administered dose. OBJECTIVE: This study evaluated the safety, tolerability, and systemic pharmacokinetics (PK) of a dry powder formulation (PUR3100) DHE when delivered via inhalation compared to intravenous delivery. METHODS: In this double-blind, double-dummy Phase 1 study, healthy volunteers (N = 26) were randomized (1:1:1:1) to one of four groups: orally inhaled placebo plus intravenous DHE 1.0 mg or orally inhaled PUR3100 (0.5, 1.0, or 1.5 mg) plus intravenous placebo. Blood samples were drawn pre-dose and at time points post-dose over 48 h. Standard PK and safety parameters were assessed and values for Cmax and area under plasma concentration time curve (AUC) were used to assess comparative exposures of PUR3100 versus intravenous DHE. RESULTS: All doses of PUR3100 were associated with a lower incidence of nausea (21% vs. 86%), vomiting (0% vs. 29%), and headache (16% vs. 57%) compared to intravenous DHE. The PK profile of PUR3100 versus intravenous DHE was characterized by a similar mean time to Cmax (5 vs. 5.5 min), with reduced AUC0-2h (1120-4320 vs. 6340), and a lower Cmax (3620-14,400 vs. 45,000). Compared to intravenous DHE 1.0 mg, the highest nominal PUR3100 dose (1.5 mg), which delivers a fine-particle dose of approximately 0.9 mg to the lungs, had a geometric mean ratio percentage (90% confidence interval [CI]) for Cmax of 32% [17.2, 59.6] and AUC0-inf of 93% (62.9, 138.5), the latter of which was not significantly different. CONCLUSIONS: Inhaled PUR3100 is associated with rapid systemic PK within the therapeutic window and an improved safety profile relative to intravenous DHE.

Safety and Efficacy of Mitapivat in Pyruvate Kinase Deficiency.

BACKGROUND: Pyruvate kinase deficiency is caused by mutations in PKLR and leads to congenital hemolytic anemia. Mitapivat is an oral, small-molecule allosteric activator of pyruvate kinase in red cells. METHODS: In this uncontrolled, phase 2 study, we evaluated the safety and efficacy of mitapivat in 52 adults with pyruvate kinase deficiency who were not receiving red-cell transfusions. The patients were randomly assigned to receive either 50 mg or 300 mg of mitapivat twice daily for a 24-week core period; eligible patients could continue treatment in an ongoing extension phase. RESULTS: Common adverse events, including headache and insomnia, occurred at the time of drug initiation and were transient; 92% of the episodes of headache and 47% of the episodes of insomnia resolved within 7 days. The most common serious adverse events, hemolytic anemia and pharyngitis, each occurred in 2 patients (4%). A total of 26 patients (50%) had an increase of more than 1.0 g per deciliter in the hemoglobin level. Among these patients, the mean maximum increase was 3.4 g per deciliter (range, 1.1 to 5.8), and the median time until the first increase of more than 1.0 g per deciliter was 10 days (range, 7 to 187); 20 patients (77%) had an increase of more than 1.0 g per deciliter in the hemoglobin level at more than 50% of visits during the core study period, with improvement in markers of hemolysis. The response was sustained in all 19 patients remaining in the extension phase, with a median follow-up of 29 months (range, 22 to 35). Hemoglobin responses were observed only in patients who had at least one missense PKLR mutation and were associated with the red-cell pyruvate kinase protein level at baseline. CONCLUSIONS: The administration of mitapivat was associated with a rapid increase in the hemoglobin level in 50% of adults with pyruvate kinase deficiency, with a sustained response during a median follow-up of 29 months during the extension phase. Adverse effects were mainly low-grade and transient. (Funded by Agios Pharmaceuticals; ClinicalTrials.gov number, NCT02476916.).

The burden of disease in pyruvate kinase deficiency: Patients' perception of the impact on health-related quality of life.

OBJECTIVES: This study explored how signs and symptoms of pyruvate kinase (PK) deficiency, a rare hemolytic anemia caused by mutations in the PKLR gene, impacts patients' health-related quality of life (HRQoL). METHODS: Interviews with 21 adults with PK deficiency in the United States, Netherlands, and Germany were conducted. Participants were asked to describe signs, symptoms, and impacts of the disease on their daily lives. Interviews were transcribed and analyzed using qualitative analysis methods. RESULTS: The most common signs and symptoms reported were yellow eyes (n = 19), tiredness (n = 18), yellow skin (n = 17), fatigue (n = 15), low energy (n = 13), and shortness of breath (n = 13). Furthermore, signs and symptoms of PK deficiency negatively impact the ability to perform physical activities, appearance, social activities, emotional states, activities of daily living, leisure activities, work and/or school, sleep, and cognitive states of those living with PK deficiency. A conceptual model is presented that further demonstrates the profound impact that signs and symptoms of PK deficiency have on dimensions of patients' HRQoL. CONCLUSIONS: This is the first study that provides patient perspective on the burden of living with PK deficiency and lays the foundation for future studies to examine the effect of pharmacologic interventions on overall HRQoL for patients living with PK deficiency.

A role for thrombopoietin in hemangioblast development.

Vascular endothelial growth factor (VEGF) and stem cell factor (SCF) act as growth factors for the hemangioblast, an embryonic progenitor of the hematopoietic and endothelial lineages. Because thrombopoietin (TPO) and its receptor, c-Mpl, regulate primitive hematopoietic populations, including bone marrow hematopoietic stem cells, we investigated whether TPO acts on the hemangioblasts that derive from differentiation of embryonic stem cells in vitro. Reverse transcriptase polymerase chain reaction analysis detected expression of c-Mpl beginning on day 3 of embryoid body differentiation when the hemangioblast first arises. In assays of the hemangioblast colony-forming cell (BL-CFC), TPO alone supported BL-CFC formation and nearly doubled the number of BL-CFC when added together with VEGF and SCF. When replated under the appropriate conditions, TPO-stimulated BL-CFC gave rise to secondary hematopoietic colonies, as well as endothelial cells, confirming their nature as hemangioblasts. Addition of a neutralizing anti-VEGF antibody did not block TPO enhancement of BL-CFC formation, suggesting that TPO acts independently of VEGF. These results establish that Mpl signaling plays a role in the earliest stages of hematopoietic development and that TPO represents a third growth factor influencing hemangioblast formation.