The unique mechanism of action of Oxbryta directly inhibits the root cause of sickling in SCD 1 , 2
BIND |
INHIBIT |
REDUCE |
IMPROVE |
Oxbryta binds directly to your patient ’ s HbS molecules |
This dose-dependent binding increases oxygen affinity , inhibiting polymerization of the HbS |
Nonclinical studies suggest that Oxbryta may inhibit RBC sickling , improve RBC deformability , and reduce whole blood viscosity |
Improve anemia ( as measured by an increase in hemoglobin ) and reduce hemolysis ( as measured by indirect bilirubin and percent reticulocyte count ) |
Learn more about Oxbryta at ExploreOxbryta . com
required , chromatography should be performed when the patient is not receiving Oxbryta therapy .
ADVERSE REACTIONS Clinical Trials Experience
Serious adverse reactions occurred in 3 % ( 3 / 88 ) of patients receiving Oxbryta 1,500 mg , which included headache , drug hypersensitivity , and pulmonary embolism occurring in 1 patient each .
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 %).
DRUG INTERACTIONS
Sensitive CYP3A4 Substrates Voxelotor increased the systemic exposure of midazolam ( a sensitive CYP3A4 substrate ). Avoid coadministration 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 Lactation
Because of the potential for serious adverse reactions in the breastfed child , including changes in the hematopoietic system , advise patients not to breastfeed while taking Oxbryta and for at least 2 weeks after the last dose .
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 .
Please see Brief Summary of Full Prescribing Information for Oxbryta on the following page for more information .
References : 1 . Oxbryta Full Prescribing Information . South San Francisco , CA : Global Blood Therapeutics , Inc .; 11 / 2019 . 2 . Vichinsky E , Hoppe CC , Ataga Kl , et al . A phase 3 randomized trial of voxelotor in sickle cell disease . N Engl J Med . 2019 ; 381 ( 6 ): 509-519 .