First Presentation of Data Specifically Focused on HbSC Genotype

Data Presented at Academy for Sickle Cell and Thalassemia (ASCAT) 11th Annual Conference

SOUTH SAN FRANCISCO, CA, USA I October 11, 2017 I Global Blood Therapeutics, Inc. (GBT) (NASDAQ:GBT) today announced the presentation of a case study highlighting the effect of GBT440 on markers of anemia and hemolysis (the destruction of red blood cells) in a patient with sickle cell disease (SCD) with the variant HbSC genotype who participated in the Phase 1/2 GBT440-001 study. The findings were presented for the first time at the Academy for Sickle Cell and Thalassemia (ASCAT) 11th Annual Conference in London. Additionally, previously announced pharmacokinetic and safety data from the ongoing Phase 2a HOPE-KIDS 1 Study of GBT440 were presented at the conference.

“SCD patients with the HbSC genotype generally experience milder symptoms than those with the more common HbSS genotype, however, they still experience significant complications and morbidities, such as painful crises, retinopathy and bone necrosis. There are no approved therapies for patients with HbSC, who make up one third of the SCD patient population. The findings from this case study underscore the potential of GBT440 to be a disease-modifying therapy across a broad population of SCD genotypes through its ability to inhibit hemoglobin polymerization, the root cause of the clinical manifestations of all genotypes of SCD,” said Ted W. Love, M.D., president and chief executive officer of GBT. “As new treatment options for people with SCD are urgently needed, we continue to advance the clinical development of GBT440, with clinical trials under way in pediatric, adolescent and adult patient groups and look forward to sharing additional data from our program at the upcoming National SCDAA Convention later this month and at the American Society of Hematology Annual Meeting in December.”

Efficacy of GBT440 in a Patient with HbSC Genotype
In the case study presented at ASCAT 2017, the clinical course of a 21-year-old woman with HbSC disease and a past medical history of vaso-occlusive crisis participated in the GBT440-001 study and a follow-on extension study is described.  During the study, she received GBT440 orally once daily for two months at a dose of 600 mg and subsequently for four months at a dose of 900 mg. At six months:

  • Her baseline hemoglobin increased by 2.2 g/dl, from 10.0 g/dL to 12.2 g/dL (within the normal range).
  • Her unconjugated bilirubin (a measure of red blood cell destruction) returned to normal, decreasing by 57 percent.
  • Her baseline reticulocyte count (a measure of how fast red blood cells are made by the bone marrow and released into the blood to compensate for hemolysis) decreased by 17 percent.
  • She reported an improvement in fatigue (her primary SCD-related symptom).
  • She did not experience any sickle cell crisis events.
  • She did not experience any treatment-related adverse events with GBT440.

Encore Presentation of HOPE-KIDS 1 Study Data
The HOPE-KIDS 1 Study data presented at ASCAT 2017 were previously presented at the 22nd Congress of the European Hematology Association (EHA) in June. Results from the single-dose adolescent (age 12 to 17) cohort (n=7) of this open-label, single- and multiple-dose study, demonstrated that the pharmacokinetics and half-life of GBT440 are similar in adolescents and adults, and that GBT440 was well tolerated. No serious or severe adverse events related to study drug were observed.

About Sickle Cell Disease (SCD)
SCD is a lifelong inherited blood disorder caused by a genetic mutation in the beta-chain of hemoglobin, which leads to the formation of abnormal hemoglobin known as sickle hemoglobin (HbS). In its deoxygenated state, HbS has a propensity to polymerize, or bind together, forming long, rigid rods within a red blood cell (RBC). The polymer rods deform RBCs to assume a sickled shape and to become inflexible, which can cause blockage in capillaries and small blood vessels. Beginning in childhood, SCD patients suffer unpredictable and recurrent episodes or crises of severe pain due to blocked blood flow to organs, which often lead to psychosocial and physical disabilities. This blocked blood flow, combined with hemolytic anemia (the destruction of RBCs), can eventually lead to multi-organ damage and early death.

About GBT440 in Sickle Cell Disease
GBT440 is being developed as an oral, once-daily therapy for patients with SCD. GBT440 works by increasing hemoglobin’s affinity for oxygen. Since oxygenated sickle hemoglobin does not polymerize, GBT believes GBT440 blocks polymerization and the resultant sickling of red blood cells. With the potential to restore normal hemoglobin function and improve oxygen delivery, GBT believes that GBT440 may potentially modify the course of SCD. In recognition of the critical need for new SCD treatments, the U.S. Food and Drug Administration (FDA) has granted GBT440 Fast Track, Orphan Drug and Rare Pediatric Disease designations for the treatment of patients with SCD. The European Medicines Agency (EMA) has included GBT440 in its Priority Medicines (PRIME) program, and the European Commission (EC) has designated GBT440 as an orphan medicinal product for the treatment of patients with SCD.

GBT is currently evaluating GBT440 in the HOPE (Hemoglobin Oxygen Affinity Modulation to Inhibit HbS PolymErization) Study, a Phase 3 clinical trial in patients age 12 and older with SCD. Additionally, GBT440 is being studied in the ongoing Phase 1/2 GBT440-001 trial and in the ongoing Phase 2a HOPE-KIDS 1 Study, an open-label, single- and multiple-dose study in pediatric patients (age 6 to 17) with SCD. HOPE-KIDS 1 is assessing the safety, tolerability, pharmacokinetics and exploratory treatment effect of GBT440.

About Global Blood Therapeutics
Global Blood Therapeutics, Inc. is a clinical-stage biopharmaceutical company dedicated to discovering, developing and commercializing novel therapeutics to treat grievous blood-based disorders with significant unmet need. GBT is developing its lead product candidate, GBT440, as an oral, once-daily therapy for sickle cell disease. GBT is also investigating GBT440 for the treatment of hypoxemic pulmonary disorders in two ongoing Phase 2a studies in patients with idiopathic pulmonary fibrosis. To learn more, please visit: www.globalbloodtx.com and follow the company on Twitter: @GBT_News.

SOURCE: Global Blood Therapeutics