CLINICAL TRIALS PROFILE FOR VOXELOTOR

All Clinical Trials for VOXELOTOR

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT02850406 ↗	Study to Evaluate the Effect of GBT440 in Pediatrics With Sickle Cell Disease	Recruiting	Global Blood Therapeutics	Phase 2	2016-05-18	This study consists of four parts, Parts A, B, C, and D. Part A is a single dose pharmacokinetic (PK) study in pediatric participants with Sickle Cell Disease. Part B is a multiple dose, safety, exploratory, efficacy, and PK study in adolescent Sickle Cell Disease participants who were 12-17 years of age. Part C is a multiple dose, safety, tolerability, and PK study, which includes the assessment of hematological effects and the effect on TCD flow velocity of voxelotor in pediatric participants with Sickle Cell Disease who are 4 to 17 years of age. Part D is a multiple dose, safety, tolerability, and PK study, which will examine the hematological effects of voxelotor in pediatric participants with Sickle Cell Disease who are between 9 months to < 4 years of age.
NCT03036813 ↗	Study to Evaluate the Effect of Voxelotor Administered Orally to Patients With Sickle Cell Disease (GBT_HOPE)	Completed	Global Blood Therapeutics	Phase 3	2016-12-01	A Phase 3, Double-blind, Randomized, Placebo-controlled, Multicenter Study of Voxelotor Administered Orally to Patients With Sickle Cell Disease
NCT03573882 ↗	Study to Assess the Effect of Long-term Treatment With Voxelotor in Participants Who Have Completed Treatment in Study GBT440-031	Active, not recruiting	Global Blood Therapeutics	Phase 3	2018-06-06	Open Label Extension Study of Voxelotor Clinical Trial Participants with Sickle Cell Disease Who Participated in Voxelotor Clinical Trials
NCT04000165 ↗	Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of Escalating Multiple Oral Doses of AG-348 in Subjects With Stable Sickle Cell Disease	Completed	National Heart, Lung, and Blood Institute (NHLBI)	Early Phase 1	2019-07-11	Background: Sickle Cell Disease (SCD) is an inherited blood disorder. People with SCD have abnormal hemoglobin in their red blood cells. Researchers are investigating the safety and efficacy of an investigational medicine called AG-348 (mitapivat sulfate) to determine if it will help people with SCD. Objective: To test the tolerability and safety of AG-348 in people with SCD. Eligibility: People ages 18 and older with SCD. Design: Participants will have 8 visits over approximately 14 weeks. At the first visit participants will be screened with a medical history; a physical exam; and blood, urine, and heart tests. At the following 5 visits participants will stay at the clinic for 1 night each. Participants will take study drug in increasing doses upto visit 6, after which the drug will be tapered off. All visits will include physical exam, blood, and urine tests. The last visit will occur 4 weeks after stopping the drug and also includes a heart test. Participants will provide DNA from the blood samples they provide. The DNA will be tested for an inherited gene that can cause differences in response to the study drug. Researchers may also test other genes to see if they can find any genes that interact with SCD.
NCT04000165 ↗	Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of Escalating Multiple Oral Doses of AG-348 in Subjects With Stable Sickle Cell Disease	Completed	National Institutes of Health Clinical Center (CC)	Early Phase 1	2019-07-11	Background: Sickle Cell Disease (SCD) is an inherited blood disorder. People with SCD have abnormal hemoglobin in their red blood cells. Researchers are investigating the safety and efficacy of an investigational medicine called AG-348 (mitapivat sulfate) to determine if it will help people with SCD. Objective: To test the tolerability and safety of AG-348 in people with SCD. Eligibility: People ages 18 and older with SCD. Design: Participants will have 8 visits over approximately 14 weeks. At the first visit participants will be screened with a medical history; a physical exam; and blood, urine, and heart tests. At the following 5 visits participants will stay at the clinic for 1 night each. Participants will take study drug in increasing doses upto visit 6, after which the drug will be tapered off. All visits will include physical exam, blood, and urine tests. The last visit will occur 4 weeks after stopping the drug and also includes a heart test. Participants will provide DNA from the blood samples they provide. The DNA will be tested for an inherited gene that can cause differences in response to the study drug. Researchers may also test other genes to see if they can find any genes that interact with SCD.
NCT04188509 ↗	Pediatric Open-Label Extension of Voxelotor	Enrolling by invitation	Global Blood Therapeutics	Phase 3	2019-11-18	Open-label extension study of voxelotor for pediatric participants ages 4 to 18 years old with Sickle Cell Disease who have participated in voxelotor clinical trials.

Clinical Trial Conditions for VOXELOTOR

Condition Name

Condition Name for VOXELOTOR
Intervention	Trials
Sickle Cell Disease	15
Sickle Cell Anemia	2
Sickle Cell Nephropathy	1
Acute Lung Injury	1

Condition MeSH

Condition MeSH for VOXELOTOR
Intervention	Trials
Anemia, Sickle Cell	17
Anemia	2
Ulcer	1
Kidney Diseases	1

Clinical Trial Locations for VOXELOTOR

Trials by Country

Trials by Country for VOXELOTOR
Location	Trials
United States	87
United Kingdom	7
Lebanon	5
Kenya	5
Egypt	4

Trials by US State

Trials by US State for VOXELOTOR
Location	Trials
Georgia	7
Pennsylvania	6
Illinois	6
Tennessee	5
Virginia	5

Clinical Trial Progress for VOXELOTOR

Clinical Trial Phase

Clinical Trial Phase for VOXELOTOR
Clinical Trial Phase	Trials
PHASE2	1
Phase 4	3
Phase 3	6

Clinical Trial Status

Clinical Trial Status for VOXELOTOR
Clinical Trial Phase	Trials
Recruiting	8
Not yet recruiting	4
Completed	3

Clinical Trial Sponsors for VOXELOTOR

Sponsor Name

Sponsor Name for VOXELOTOR
Sponsor	Trials
Global Blood Therapeutics	13
National Heart, Lung, and Blood Institute (NHLBI)	2
Pfizer	2

Sponsor Type

Sponsor Type for VOXELOTOR
Sponsor	Trials
Industry	15
Other	10
NIH	3

Voxelotor (Oxbryta) Clinical Trials Update, Market Analysis, and Projection

Last updated: April 27, 2026

What is voxelotor’s current clinical positioning?

Voxelotor (Oxbryta) is a hemoglobin S (HbS) polymerization inhibitor used for sickle cell disease (SCD). Commercially, it is approved for patients aged 4 years and older with SCD, including those with hemolytic anemia, to increase hemoglobin (Hb) and reduce hemolysis-related outcomes in the available label.

What clinical trials and evidence support voxelotor’s label and durability?

Voxelotor’s core clinical evidence is anchored to Phase 3 data and ongoing follow-on programs designed to support durability of hemoglobin response, long-term safety, and broader clinical endpoints.

Phase 3 pivotal dataset

The pivotal Phase 3 program established efficacy using hemoglobin response and hemolysis markers in SCD patients. Key endpoints used in the registration program included:

• Hb increase from baseline at defined timepoints.
• Reduction in markers of hemolysis, including indirect markers reported in the program.
• Sustained response in treated populations across follow-up.

What do recent trial developments typically target (commercially actionable)?

Recent development activity for voxelotor has focused on:

• Durability of Hb response over longer horizons.
• Safety and tolerability in broader patient exposure windows.
• Endpoint expansion beyond Hb response to disease-modifying proxies used by payers and clinicians (for market access arguments).

Core regulatory basis for approval remains the Phase 3 hemoglobin-response package, supplemented by post-marketing and longer-term follow-up consistent with SCD chronic-use requirements. (Source: FDA label and review materials for Oxbryta [1,2].)

What safety and tolerability profile matters to adoption?

Commercial adoption in SCD relies on:

• Chronic dosing tolerability
• Low discontinuation rates
• Predictable lab and adverse-event monitoring

Voxelotor’s label provides the safety framework that prescribers and payers use for risk stratification and formulary placement. (Source: FDA label [1].)

What is the market for voxelotor and who pays?

The addressable market for voxelotor is driven by the size of the diagnosed SCD population, treated eligible segments under label criteria, and payer willingness to reimburse a chronic therapy with hemoglobin-focused benefit.

Demand drivers

1. Eligible patient pool growth
   • SCD diagnosis rates and survival improvements expand treated populations over time.
2. Hb response as the primary value driver
   • Voxelotor’s differentiation is measured through hemoglobin improvement, which payers can map to clinical goals (anemia burden reduction) and sometimes to reduced downstream resource use.
3. Formulary dynamics
   • SCD pharmacy benefit management tends to favor therapies with established outcomes and clear monitoring protocols.

Competitive landscape

Voxelotor competes within the SCD disease-modifying and anemia-burden management space, alongside:

• Disease-modifying agents that reduce sickling events and crisis frequency (class-dependent).
• Supportive anemia-directed therapies that can compete indirectly based on clinician preference and payer pathways.

Voxelotor’s competitive position is primarily tied to:

• Hb improvement in chronic use
• Payer acceptance of hemoglobin-focused endpoints
• Patient-reported and clinician-assessed tolerability

What does voxelotor’s performance imply for near-term sales?

A clean sales forecast requires current revenue and share by quarter or at least annual figures. This prompt does not include those data, and the constraint here is to avoid fabricating figures. What can be stated with direct evidentiary grounding is the commercialization logic anchored to:

• Label eligibility (age 4+ with SCD, hemoglobin benefit focus) [1]
• Regulatory acceptance of hemoglobin-focused endpoints in registration [2]
• Ongoing clinical evidence strategy targeting durability and long-term safety consistent with chronic use needs [1,2]

What market and projection framework fits voxelotor?

Given the data constraints, the most decision-useful projection framework is a scenario-based adoption model using fixed structural parameters that are known from regulatory and clinical positioning, without inserting unsupported numeric revenue. The framework is built around three levers:

1) Treated eligible population growth

• Growth comes from diagnosed prevalence trends and treatment uptake within managed care.
• Adoption is gated by: label inclusion, prescriber confidence, and formulary coverage.

2) Persistence (on-therapy duration)

• Voxelotor is chronic therapy; the persistence rate drives cumulative revenue more than year-1 conversions.
• Durability evidence and safety management determine persistence. (Source: FDA label [1].)

3) Payer leverage and endpoint acceptance

• Payers respond to endpoints that align to utilization reduction.
• Hemoglobin improvements are central to how voxelotor is justified in care pathways. (Source: FDA label and review context [1,2].)

This structure allows forecasting that is defensible in investment or R&D portfolio contexts once actual sales baselines are added from internal or public databases.

What is the key regulatory footprint affecting timelines and market access?

Voxelotor’s U.S. regulatory status shapes its adoption curve through:

• Label eligibility boundaries that determine pharmacy benefit inclusion
• Prescribing criteria and monitoring expectations that influence prescriber comfort and payer controls
• Safety label content that affects prior authorization and step therapy requirements

These points are directly set out in the FDA-approved labeling. (Source: FDA label [1].)

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Key Takeaways

• Voxelotor’s clinical and commercial positioning centers on hemoglobin improvement in SCD, supported by Phase 3 evidence used for regulatory approval. (Sources: FDA label and approval review [1,2].)
• Market uptake is driven by three levers: eligible population growth, therapy persistence, and payer acceptance of hemoglobin-focused endpoints. (Source: FDA label [1].)
• A numeric sales forecast cannot be produced from the provided prompt without fabricating revenue or share assumptions. A decision-grade projection is best built from a structured adoption model using label and evidence parameters anchored in the FDA review package.

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FAQs

1) What is voxelotor approved to do in sickle cell disease?

Voxelotor is approved to increase hemoglobin in patients with sickle cell disease and to address hemolysis-related anemia burden within its labeled indications. (Source: FDA label [1].)

2) What endpoint supported voxelotor’s approval?

The regulatory package is anchored to hemoglobin response outcomes and related measures in the pivotal trial program. (Sources: FDA label and approval review [1,2].)

3) Who can receive voxelotor under the label?

The FDA label includes pediatric eligibility beginning at age 4, with SCD populations specified under the approved indication. (Source: FDA label [1].)

4) What is the main driver for payer adoption?

Payers typically anchor on clinically measurable benefit that is consistent with chronic anemia burden, with hemoglobin improvement as the central value metric supported in the labeling and review context. (Source: FDA label [1].)

5) Does voxelotor require long-term use?

Yes, voxelotor is used as a chronic therapy in SCD to maintain hemoglobin improvements, making persistence and long-term tolerability key to market performance. (Source: FDA label [1].)

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References

[1] U.S. Food and Drug Administration. (n.d.). Oxbryta (voxelotor) prescribing information. FDA.
[2] U.S. Food and Drug Administration. (n.d.). Oxbryta (voxelotor) review documents and approval materials. FDA.