TNF-α inhibitor (PEGylated Fab') Pregnancy: Large body of data (>1500 first-trimester exposures) indicates no malformative nor feto/neonatal toxicity. Placental transfer is negligible/low. Consider adequate contraception in women of childbearing potential; if clearing drug before conception, continue contraception for 5 months after the last dose. Wait a minimum of 5 months after the mother's last dose in pregnancy before giving live/live-attenuated vaccines to the infant.

Certolizumab pegol

Brand names: Cimzia

Certolizumab pegol is a PEGylated anti-TNF biologic given by subcutaneous injection for rheumatoid arthritis, axial spondyloarthritis, psoriatic arthritis and other inflammatory conditions.

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: 400 mg loading (2 x 200 mg SC) at weeks 0, 2 and 4, then 200 mg every 2 weeks (maintenance)

Route: subcutaneous injection

Frequency: loading at weeks 0, 2, 4; then every 2 weeks

Treatment initiated and supervised by specialist physicians. Loading dose (rheumatoid arthritis, psoriatic arthritis, axial spondyloarthritis, plaque psoriasis): 400 mg (2 SC injections of 200 mg) at weeks 0, 2 and 4. Maintenance: rheumatoid arthritis 200 mg every 2 weeks (alternative 400 mg every 4 weeks once response confirmed); axial spondyloarthritis 200 mg every 2 weeks or 400 mg every 4 weeks (after >=1 year sustained remission, 200 mg every 4 weeks may be considered); psoriatic arthritis 200 mg every 2 weeks (alternative 400 mg every 4 weeks); plaque psoriasis 200 mg every 2 weeks (400 mg every 2 weeks if insufficient response). For RA and PsA, MTX should be continued where appropriate. PAEDIATRIC (UK SPC): safety and efficacy not established; should not be used in children/adolescents below 18 years. Injected into thigh or abdomen. No dose recommendations for renal or hepatic impairment (not studied).

Dose adjustments

Renal

Not studied in renal impairment; no dose recommendations can be made.

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC; 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

Hypersensitivity to the active substance or to any of the excipients
Active tuberculosis or other severe infections such as sepsis or opportunistic infections
Moderate to severe heart failure (NYHA class III/IV)

Side effects

Upper respiratory tract infections
Rash
Urinary tract infections
Serious infections (including sepsis, tuberculosis, opportunistic infections)
Administration site (injection site) reactions

Interactions

Anakinra, abatacept — combination not recommended (increased risk of serious infections with TNF blockers)
Rituximab, natalizumab — combination not recommended
Live (including attenuated) vaccines — avoid during or immediately prior to therapy
May cause erroneously elevated aPTT (activated partial thromboplastin time) assay results

Clinical monograph

How it works

It is a pegylated Fab' fragment that binds and neutralises tumour necrosis factor alpha; lacking an Fc region, it does not fix complement and has minimal placental transfer.

Prescribing in practice

As a TNF inhibitor it increases the risk of serious infection including reactivation of latent tuberculosis, so screening for active and latent TB and other infections is required before starting.
It should be avoided in moderate-to-severe heart failure and used cautiously in those with demyelinating disease or a history of malignancy.
Minimal placental transfer makes it a frequently preferred anti-TNF option in pregnancy when treatment is needed.

Monitoring

Monitor for signs of infection and treatment response, with tuberculosis and hepatitis screening before initiation and periodic clinical review.

Counselling the patient

Report fever, persistent cough or other signs of infection promptly.
Avoid live vaccines, and store and self-inject as trained.
Tell your team if you are pregnant or planning pregnancy.

Evidence & guidelines

Use is supported by randomised controlled trials across its licensed indications and by NICE technology appraisals for inflammatory arthritis.

Reference: NICE TA186/TA383; 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