Voxelotor (formerly GBT440, Global Blood Therapeutics, Inc.) is being developed as an oral, once-daily therapy for sickle cell disease (SCD). Drawing on the clinical benefits previously seen in adult patients with SCD and in recognition of the critical need for new SCD treatments, voxelotor has received European Medicines Agency (EMA) Priority Medicines (PRIME) designation for the treatment of SCD. Voxelotor is a haemoglobin oxygen-affinity modulator designed to prevent haemoglobin polymerization, the main cause of SCD pathophysiology, with potential to modify the course of SCD early on as to alleviate the symptom burden, prolong life expectancy and improve patient’s quality of life. Promising and reassuring preliminary results from the HOPE-KIDS 1 Study (GBT440-007) [ClinicalTrials.gov Identifier: NCT02850406] were presented by Carolyn C. Hoppe, MD, at the 2017 ASH Annual Meeting. The study evaluates the safety, tolerability, pharmacokinetics and exploratory treatment effect of voxelotor in a pediatric population (6 to 17 years) with SCD.

Results are reported for 12 patients (ages 12-17 years) in the 900 mg cohort, who were treated for 16 weeks, as follows:

- Increased haemoglobin levels and improved clinical measures of hemolysis. Six of eleven patients achieved a hemoglobin response of > 1 g/dl increase.

- Reduced daily symptoms at 16 weeks as assessed by total symptom scores (TSS), which improved in 10 of 12 patients, despite low symptom burden scores at baseline.

- Favourable tolerability profile. No drug-related serious adverse events or drug-related discontinuations due to adverse events.

Global Blood Therapeutics, Inc. has initiated a phase III clinical study of GBT440 in patients (12 to 65 years) with SCD [ClinicalTrials.gov Identifier: NCT03036813].

More information:ASH 2017 abstract,GBT Announcement, Pharmacy and Therapeutics Journal