siRNA targeting ALAS1

Givosiran

Brand names: Givlaari

Givosiran is a small interfering RNA (siRNA) therapy used to treat acute hepatic porphyria in adults and adolescents.

Dosing — being independently re-sourced

ClinCalc Pro is rebuilding its dose data from primary open sources — the manufacturer SmPC (eMC), the WHO Model Formulary and other official references — under clinician review. This drug's structured dose is not yet published here. Confirm all doses against the product SmPC and your local formulary before prescribing.

Clinical monograph

How it works

It targets and reduces hepatic aminolevulinic acid synthase 1 (ALAS1) messenger RNA, lowering accumulation of the neurotoxic intermediates that trigger porphyria attacks.

Prescribing in practice

Hepatotoxicity with transaminase elevations and anaphylactic reactions have been reported, so liver function should be checked and the patient observed.
Changes in renal function have been observed, so renal monitoring is advised.
It is administered by subcutaneous injection under specialist supervision.

Monitoring

Monitor liver function before and during treatment and assess renal function periodically, watching for hypersensitivity reactions.

Counselling the patient

Report any severe allergic reaction, or symptoms such as jaundice or dark urine.
Attend appointments for blood test monitoring.
This is a specialist treatment given as a regular injection.

Evidence & guidelines

Givosiran reduces the rate of porphyria attacks in acute hepatic porphyria, supported by the ENVISION trial and its licensed indication.

Reference: NICE TA836 (Givosiran); SmPC; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Pathways