Voxelotor

How it works

It binds reversibly to haemoglobin and increases its affinity for oxygen, stabilising the oxygenated state and reducing haemoglobin polymerisation and red-cell sickling.

Prescribing in practice

• Prescribers should be aware that the marketing authorisation has been withdrawn following safety concerns about an unfavourable benefit-risk balance, so current regulatory status and MHRA advice must be checked before any use.
• Hypersensitivity reactions, including rash and urticaria, have been reported and warrant discontinuation if serious.
• By raising measured haemoglobin-oxygen affinity, it can interfere with some oximetry and oxygen-saturation readings, which should be interpreted with caution.

Monitoring

Monitor haemoglobin response and for hypersensitivity, interpreting oxygen-saturation measurements with awareness of altered oxygen affinity.

Counselling the patient

• Be aware that this medicine's availability has changed following safety review; follow your specialist's advice.
• Report any rash or allergic reaction promptly.
• Pulse oximeter readings may be less reliable while taking this medicine.

Evidence & guidelines

Voxelotor was studied in the HOPE trial in sickle cell disease, but its marketing authorisation was subsequently withdrawn after safety review.