Risdiplam

How it works

It modifies splicing of the SMN2 gene transcript to promote inclusion of exon 7, increasing production of functional, full-length SMN protein and thereby supporting motor neuron survival.

Prescribing in practice

• Because it is potentially teratogenic and may affect fertility, appropriate contraceptive and reproductive counselling is required for those of childbearing potential.
• It is a daily oral medicine that should be taken consistently, and care is needed with co-administration of drugs that are substrates of certain transporters owing to potential interactions.
• Prescribe within specialist neuromuscular services according to the SPC and a children's formulary, including measures to ensure accurate administration of the oral solution.

Monitoring

Monitor motor function and treatment response within a specialist service; specific reproductive-safety counselling is required for those of childbearing potential.

Counselling the patient

• Explain that the medicine is taken by mouth every day at around the same time and aims to improve or preserve muscle function.
• Use the device provided to measure the dose accurately and follow instructions on handling the oral solution.
• Discuss contraception and pregnancy planning with the specialist team before and during treatment.

Evidence & guidelines

Risdiplam is approved for SMA on the basis of the FIREFISH and SUNFISH trials, which showed improvements in motor milestones and function across infantile- and later-onset disease, and it is available in the UK through specialist commissioning.