Factor D inhibitor (oral complement inhibitor, adjunctive) Pregnancy: No available data in pregnant individuals to evaluate drug-associated risk; there are risks to mother and fetus from untreated PNH in pregnancy. Use in pregnant women or women planning to become pregnant may be considered following an assessment of the risks and benefits (US labelling §8.1).

Danicopan

Brand names: Voydeya

Danicopan is an oral complement factor D inhibitor used as add-on therapy in paroxysmal nocturnal haemoglobinuria (PNH) for patients with clinically significant extravascular haemolysis on a C5 inhibitor.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: 150 mg three times a day

Route: Oral

Frequency: Three times a day, taken at around the same time every day; with or without food

Max: 200 mg three times a day (labelling refers to this as the maximum recommended human dose)

US prescribing information (VOYDEYA, Alexion) — no UK SPC posology was available in the fetched bundle, so all values below are from US labelling and must be checked against the UK SPC. Starting dose: 150 mg three times a day orally. Dose adjustment: the dose can be increased to 200 mg three times a day if the patient's haemoglobin has not increased by greater than 2 g/dL after 4 weeks of therapy, if the patient required a transfusion during the previous 4 weeks, or to achieve an appropriate Hgb response based on clinical judgement. Missed dose: take as soon as remembered unless within 3 hours before the next dose, in which case skip the missed dose and take at the next regularly scheduled time; do not take two or more doses at the same time. Before starting: vaccinate against encapsulated bacteria, including Neisseria meningitidis (serogroups A, C, W, Y and B) and Streptococcus pneumoniae, according to current ACIP recommendations at least 2 weeks prior to initiation; if urgent therapy is needed in a patient not up to date, give antibacterial prophylaxis and vaccinate as soon as possible. US labelling also requires prescribers to enrol in the VOYDEYA REMS (US-specific). Monitoring: assess liver enzymes before initiation and periodically during treatment (consider interruption or discontinuation if elevations are clinically significant or the patient becomes symptomatic); monitor serum lipids periodically and start cholesterol-lowering medication if indicated. Paediatric: safety and effectiveness for the treatment of PNH in paediatric patients have not been established. Geriatric: clinical studies did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects. Formulation available as 50 mg and 100 mg film-coated tablets.

Dose auto-extracted from US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

Initiation in patients with unresolved serious infection caused by encapsulated bacteria, including Neisseria meningitidis, Streptococcus pneumoniae or Haemophilus influenzae type B

Side effects

Headache (most frequent adverse reaction, incidence 10% or greater)
Serious infections caused by encapsulated bacteria (clinically significant adverse reaction)
Hepatic enzyme increases (clinically significant adverse reaction)
Hyperlipidaemia (clinically significant adverse reaction)

Interactions

BCRP substrates — danicopan is a BCRP inhibitor and increases plasma concentrations of BCRP substrates; monitor more frequently for adverse reactions and consider dose reduction of the BCRP substrate
Rosuvastatin — exposure significantly increased; rosuvastatin dose should not exceed 10 mg once daily during concomitant use
P-gp substrates — danicopan is a P-glycoprotein inhibitor and may increase plasma concentrations; dose adjustment might be necessary where minimal concentration changes may lead to serious adverse reactions

Clinical monograph

How it works

It inhibits factor D, a protease of the alternative complement pathway, thereby reducing the C3-mediated opsonisation that drives extravascular haemolysis when terminal (C5) inhibition is already in place.

Prescribing in practice

As a complement inhibitor it increases the risk of infection with encapsulated organisms, so meningococcal and other appropriate vaccination must be ensured before starting.
It is used as an add-on to an existing C5 inhibitor, not as monotherapy, and the C5 inhibitor should be continued.
Hepatic enzymes may rise; baseline and periodic liver function assessment is appropriate.

Monitoring

Monitor haemoglobin and markers of haemolysis, liver function, and for any sign of serious infection.

Counselling the patient

Continue your existing complement medicine; this is added on top of it, not a replacement.
Carry your patient safety card and seek urgent care for fever, severe headache or neck stiffness.
Keep meningococcal and other recommended vaccinations up to date.

Evidence & guidelines

The ALPHA trial showed improvement in haemoglobin with danicopan added to C5 inhibition for extravascular haemolysis in PNH; consult current prescribing references.

Reference: NICE TA evaluation; SmPC; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Calculators

Pathways