Indications and Usage
Oxbryta is indicated for the treatment of sickle cell disease (SCD) in adults and pediatric patients 12 years of age and older.
This indication is approved under accelerated approval based on increase in hemoglobin (Hb). Continued approval for this indication may be contingent upon verification and description of clinical benefit in confirmatory trial(s).
Important Safety Information
Oxbryta is contraindicated in patients with a history of serious drug hypersensitivity reaction to voxelotor or excipients.
Warnings and precautions
Serious hypersensitivity reactions after administration of Oxbryta have occurred in <1% of patients treated. Clinical manifestations may include generalized rash, urticaria, mild shortness of breath, mild facial swelling, and eosinophilia.
If hypersensitivity reactions occur, discontinue Oxbryta and administer appropriate medical therapy. Do not reinitiate Oxbryta in patients who experience these symptoms with previous use.
Laboratory Test Interference
Oxbryta administration may interfere with measurement of Hb subtypes by HPLC. If precise quantitation of Hb species is required, chromatography should be performed when the patient is not receiving Oxbryta therapy.
Adverse Reactions (≥10%) in patients receiving Oxbryta with a difference of >3% compared to placebo: Headache (26% vs. 22%), Diarrhea (20% vs. 10%), Abdominal Pain (19% vs. 13%), Nausea (17% vs. 10%), Fatigue (14% vs. 10%), Rash (14% vs. 10%), and Pyrexia (12% vs. 7%).
Sensitive CYP3A4 Substrates
Avoid co-administration with sensitive CYP3A4 substrates with a narrow therapeutic index. If unavoidable, consider dose reduction of the CYP3A4 substrate(s).
Strong CYP3A4 Inhibitors or Fluconazole
Co-administration of strong CYP3A4 inhibitors or fluconazole may increase voxelotor plasma concentrations and may lead to increased toxicity. Avoid co-administration of strong CYP3A4 inhibitors or fluconazole. Decrease Oxbryta dosage if unavoidable.
Strong or Moderate CYP3A4 Inducers
Co-administration of strong or moderate CYP3A4 inducers may decrease voxelotor plasma concentrations and may lead to reduced efficacy. Avoid co-administration of strong or moderate CYP3A4 inducers. Increase the Oxbryta dosage if unavoidable.
Use in specific populations
Advise patients not to breastfeed while taking Oxbryta.
Recommended Dosage for Hepatic Impairment
Severe hepatic impairment increases voxelotor exposures. Reduce dose to 1,000 mg orally once daily for severe hepatic (Child Pugh C) impairment.
For additional information about Oxbryta, please see Full Prescribing information.
Reference: 1. Oxbryta Full Prescribing Information. South San Francisco, CA: Global Blood Therapeutics, Inc.; 11/2019.