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GBT is committed to developing and delivering therapies for people with sickle cell disease

Our goal is to advance the care and treatment of people with SCD through science, innovative medicines and access to solutions

Driven by a deep and urgent desire to improve the care of people with sickle cell disease (SCD), we are collaborating with the SCD community to increase awareness of the disease and how it affects patients, changing the way people with SCD are perceived by society at large and helping patients gain access to innovative medicines. Building on the extensive knowledge gained from years of research, we are focused on changing the treatment paradigm for SCD.

Development pipeline addressing significant patient needs in SCD

Program Discovery Preclinical Early Clinical (Phase 1/2) Late Clinical (Phase 3/4) Approved


FDA-approved SCD treatment for ages 4 and older


HOPE-KIDS 2: Post-approval confirmatory study measuring the mean change in transcranial doppler (TCD) in SCD patients 2-15 years of age


ActIVe Study: Planned Phase 4 study evaluating daily physical activity in SCD patients 12 years of age and older


HOPE-KIDS 1: Ongoing study in SCD patients 9 months-17 years of age


Potential treatment to reduce the frequency of vaso-occlusive crises (VOCs) and reduce hospital re-admissions post-VOC


Potential next-generation sickle hemoglobin polymerization inhibitor

HbF inducers*

Potential treatments for SCD and beta thalassemia


Potential treatments for SCD

Inflammation & Oxidative Stress Reduction

Potential treatments for SCD

  1. Collaboration with Syros Pharmaceuticals

Our development programs

Unlike other biotech companies, which typically begin with a molecule and search for an indication, our founding vision involved developing therapies to specifically address SCD.


Voxelotor is an oral therapy taken once daily that directly inhibits sickle hemoglobin polymerization, which causes red blood cells (RBCs) to deform and become sickle shaped. Voxelotor works by binding to hemoglobin and stabilizing RBCs in an oxygenated state. This increases hemoglobin’s affinity for oxygen and inhibits polymerization and the resultant sickling and destruction of RBCs.

GBT is committed to studying the potential of voxelotor to slow the progression of SCD and its devasting downstream effects across a wide range of studies, including the HOPE-KIDS 2 post-approval confirmatory study using transcranial doppler (TCD) flow velocity to evaluate reduction in stroke risk in children 2 to 15 years of age.

In recognition of the critical need for new SCD treatments, voxelotor was granted Breakthrough Therapy, Fast Track, Orphan Drug and Rare Pediatric Disease designations by the U.S. Food and Drug Administration (FDA) for the treatment of patients with SCD, as well as Priority Medicines (PRIME) designation from the European Medicines Agency (EMA). The European Commission (EC) has designated voxelotor as an orphan medicinal product for the treatment of patients with SCD.


GBT is developing inclacumab – a novel, fully human monoclonal antibody P-selectin inhibitor – for SCD patients with frequent pain crises, also known as vaso-occlusive crises (VOCs). P-selectin inhibition is clinically validated to reduce VOCs,1 a complication of SCD.

GBT has an exclusive worldwide licensing agreement with Roche for inclacumab, which has established pharmacokinetic data, safety and tolerability in more than 500 patients. We have initiated two pivotal Phase 3 studies evaluating the effect of inclacumab on reducing the frequency of VOCs and on hospital readmissions for people with SCD. The THRIVE (Therapy for Reduction with Inclacumab of VOC Episodes) Studies are currently recruiting.

Disease Program Study Study Phase Learn More
Sickle Cell Disease Inclacumab GBT2104-132: Multicenter Study Evaluating a Single Dose of Inclacumab to Reduce Re-admission and Recurrent Vaso-occlusive Crises Phase 3
Sickle Cell Disease Inclacumab GBT2104-131: A Study to Assess the Safety and Efficacy of Inclacumab in Participants with Sickle Cell Disease Experiencing Vaso-occlusive Crises Phase 3

GBT021601 (GBT601)

Discovered and designed by GBT’s research and development team, GBT601 has the same mechanism of action as voxelotor, with the potential for greater efficacy by achieving higher hemoglobin levels and occupancy at lower doses, as demonstrated in preclinical studies.

GBT601 is being studied in a single and multiple ascending dose Phase 1 study assessing the safety, tolerability, pharmacokinetics and pharmacodynamics of GBT601 in up to six people with SCD ages 18 to 60 years. This study follows an ongoing first-in-human trial to determine safe and tolerable dosing.

Disease Program Study Study Phase Learn More
Sickle Cell Disease GBT601 GBT021601-012: Single Dose and Multiple Ascending Dose Study Evaluating the Pharmacokinetics, Safety, Tolerability, and Pharmacodynamics of GBT601 in Sickle Cell Disease Patients Phase 1
Sickle Cell Disease GBT601 GBT021601-011: Study Evaluating Single and Multiple Ascending Doses of GBT601 in Healthy Participants Phase 1
  1. Ataga, K. et al. N Engl J Med. 2017 Feb 2;376(5):429-439.