selumetinib: prescribing and clinical use
Focused clinical detail for use alongside current product information, local policy and patient-specific assessment.
selumetinib: clinical details
Prescribing considerations
- Initiate under a clinician experienced in NF1-related tumours.
- Review cardiac function, ocular history, hepatic function, pregnancy potential and interacting medicines before treatment.
- New visual symptoms require prompt ophthalmological assessment.
- Treatment interruption, adjustment or discontinuation may be necessary for clinically important cardiac, ocular, hepatic or other toxicity.
- Moderate hepatic impairment requires specialist prescribing review; exposure may also be higher in some Asian patients.
Contraindications and cautions
- Hypersensitivity to selumetinib or any formulation excipient.
- Severe hepatic impairment.
Monitoring
- Left ventricular ejection fraction before treatment and periodically thereafter.
- Ophthalmological assessment before treatment and whenever new visual disturbance occurs.
- Liver tests before treatment, regularly during early treatment and subsequently as clinically indicated.
- Clinical assessment of gastrointestinal, skin, nail and muscle toxicity; use relevant laboratory tests where indicated.
- Pregnancy testing before treatment when appropriate.
Clinical pharmacology
Selumetinib is a selective MEK1/2 inhibitor that suppresses RAF–MEK–ERK signalling. It is highly protein bound and is metabolised mainly through CYP3A4, with contributions from CYP2C19 and other enzymes; an active N-desmethyl metabolite contributes to overall activity.
Formulation and product differences
- The granule formulation contains granules inside capsules designed to be opened and sprinkled onto soft food; the shell is discarded.
- It is intended for children aged 1 to under 7 years and older patients with swallowing difficulties.
- Hard capsules are an alternative for eligible patients who can swallow them whole.
- Granules have comparable overall systemic exposure to hard capsules but a lower peak concentration.
selumetinib preparations and strengths
Capsule
Route: Oral
Strengths: 5 mg
selumetinib interactions
Give the specialist and pharmacist a complete list of prescribed, non-prescribed and herbal products. Important examples include:
Clarithromycin, oral ketoconazole and other strong CYP3A4 inhibitors
May increase selumetinib exposure and adverse effects, so concurrent use should generally be avoided.
Fluconazole, erythromycin, fluoxetine or omeprazole
May increase selumetinib exposure through CYP3A4 or CYP2C19 inhibition and require specialist review.
Rifampicin, carbamazepine, phenytoin and St John’s wort
May reduce selumetinib exposure and effectiveness, so concurrent use should be avoided.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.