Certolizumab Pegol (Cimzia) for Psoriasis: Mechanism, Evidence and Pregnancy Safety
Certolizumab pegol (brand name Cimzia) is a TNF-alpha inhibitor biologic approved for moderate-to-severe plaque psoriasis and active psoriatic arthritis, and it holds a distinct place among the psoriasis biologics covered elsewhere on this site: it is built without the molecular component that lets most other antibody-based biologics cross the placenta. That single structural detail has made certolizumab pegol the most extensively studied biologic for pregnancy and breastfeeding in both dermatology and rheumatology. This guide explains how certolizumab pegol works, what the pivotal CIMPASI and CIMPACT trials found for psoriasis, its safety profile, what access and cost currently look like in India, and how it fits alongside an integrative Ayurvedic approach to long-term psoriasis management.
What Is Certolizumab Pegol?
Certolizumab pegol is a PEGylated Fab’ fragment of a humanized monoclonal antibody directed against tumour necrosis factor-alpha (TNF-alpha), one of the key inflammatory signalling proteins that drives plaque formation in psoriasis and joint inflammation in psoriatic arthritis. Structurally, it differs from every other TNF inhibitor used in psoriasis care: adalimumab and infliximab are full-length antibodies, and etanercept is a receptor-fusion protein, but all three carry an Fc region. Certolizumab pegol has no Fc region at all. Instead, a polyethylene glycol (PEG) molecule is attached to the antibody fragment, which extends its circulating half-life to roughly 11 days without requiring the Fc portion that other biologics rely on for longevity. This single structural difference is the basis for two things covered later in this guide: its pregnancy safety profile, and its place within the broader TNF-inhibitor family that also includes etanercept, covered in detail elsewhere on this site.
How Does It Work, and Who Is It Typically Considered For?
By binding and neutralising both soluble and membrane-bound TNF-alpha, certolizumab pegol interrupts the inflammatory cascade that drives keratinocyte overproduction in plaque psoriasis and synovial inflammation in psoriatic arthritis. It carries two separate approvals relevant here: for active psoriatic arthritis, approved by the FDA in 2013 based on the RAPID-PsA trial, and for moderate-to-severe plaque psoriasis, approved in May 2018 based on the CIMPASI-1 and CIMPASI-2 trials. It is also approved for rheumatoid arthritis, axial spondyloarthritis and Crohn’s disease, so dermatologists sometimes see patients already established on it for one of these other conditions who also have psoriasis or psoriatic arthritis.
In practice, certolizumab pegol tends to be considered for adults with moderate-to-severe plaque psoriasis or active psoriatic arthritis who need a systemic or biologic option and who have had an inadequate response to, or cannot use, topical treatment and phototherapy. It is used particularly often — specifically because of the pregnancy data discussed below — by women who are pregnant, planning a pregnancy, or breastfeeding and need continued systemic disease control for psoriasis or psoriatic arthritis.
Dosing (General, Not Patient-Specific)
For plaque psoriasis, the approved regimen is 400 mg, given as two 200 mg subcutaneous injections, every other week. For some patients weighing 90 kg or less, a loading regimen of 400 mg at weeks 0, 2 and 4, followed by 200 mg every other week, may be used instead. For psoriatic arthritis, dosing options include an initial loading dose followed by 200 mg every other week, or 400 mg once monthly. As with every biologic covered on this site, the specific dose, frequency and any adjustment is a decision your prescribing doctor makes based on your weight, disease severity, response and other health conditions — this is general, class-level information only, not a prescription.
How Effective Is Certolizumab Pegol for Psoriasis?
CIMPASI-1 and CIMPASI-2: The Pivotal Psoriasis Trials
CIMPASI-1 and CIMPASI-2 were the two phase 3, placebo-controlled trials that supported the 2018 psoriasis approval. At week 48, roughly 73% of patients on the 200 mg dose and about 84% of patients on the 400 mg dose had reached PASI 75 (a 75% improvement in psoriasis severity), while roughly 51% and 63% respectively reached the more stringent PASI 90 mark. A three-year long-term follow-up of both trials, published in the British Journal of Dermatology, found these response rates were generally sustained over time in patients who continued treatment.
CIMPACT: A Head-to-Head Comparison
A separate trial, CIMPACT, compared certolizumab pegol directly against etanercept and found that at week 12, the 400 mg every-other-week dose produced a higher PASI 75 response (66.7%) than etanercept (53.3%), though the difference at the 200 mg dose was not statistically significant. For psoriatic arthritis, the RAPID-PsA trial that supported the 2013 approval found significantly higher rates of joint symptom improvement (measured by ACR20 response) compared with placebo, sustained through long-term follow-up, which remains the basis for its continued use in psoriatic arthritis today.
Side Effects and Safety Considerations
Certolizumab pegol carries the same class-wide boxed warning as other TNF inhibitors used in psoriasis and psoriatic arthritis care. Serious infections, including reactivation of latent tuberculosis, have been reported, which is why screening for latent TB is required before starting treatment and periodically during it. Lymphoma and other malignancies, some fatal, have been reported in children and adolescents treated with TNF blockers as a class, which is one reason certolizumab pegol is not indicated for use in children. The most commonly reported side effects, occurring in roughly 1 to 10% of patients, include upper respiratory infections, injection-site reactions, rash, headache, and gastrointestinal symptoms such as abdominal pain and nausea. Patients are also screened for hepatitis B before starting, cautioned against live vaccines while on treatment, and monitored for symptoms of heart failure or lupus-like reactions, consistent with other biologics in this class.
Certolizumab Pegol and Pregnancy: What the Evidence Actually Shows
This is the area where certolizumab pegol genuinely stands apart from every other psoriasis biologic covered on this site. Most TNF inhibitors and other antibody-based biologics carry an Fc region that actively binds the neonatal Fc receptor (FcRn) in the placenta — the mechanism that transports maternal antibodies, and unintentionally these drugs, into the fetal circulation, with transfer increasing through the second and third trimesters. Because certolizumab pegol has no Fc region, it is not actively transported across the placenta in the same way.
This isn’t theoretical. The CRIB study, a prospective pharmacokinetic study of 16 mother-infant pairs, found certolizumab pegol levels in every infant were below the lower limit of quantification at birth, meaning essentially no detectable drug had crossed over. A pooled analysis across more than 11,000 trial participants supported the same conclusion of minimal to no placental transfer. For breastfeeding, the CRADLE study measured drug levels in the breast milk of 18 mothers and found a median relative infant dose of about 0.125% — far below the roughly 10% threshold generally considered acceptable during lactation — with no serious adverse events reported in the breastfed infants. A larger pregnancy-outcomes cohort following 538 women exposed to certolizumab pegol found rates of miscarriage, stillbirth and major congenital malformation broadly similar to the general population, though this data lacks an untreated comparison group and should be read with that limitation in mind.
Based on this evidence, clinical consensus guidance — including a Canadian dermatology consensus statement — considers certolizumab pegol usable across all three trimesters of pregnancy and during breastfeeding, and many clinicians consider it a preferred systemic option for psoriasis or psoriatic arthritis patients who are pregnant, actively planning a pregnancy, or breastfeeding. This remains an individualized decision made with your treating dermatologist or rheumatologist, ideally in coordination with your obstetrician, and it does not mean every pregnant patient needs to be on a biologic — many require no systemic treatment at all. Our guide to managing psoriasis safely during pregnancy covers this decision in more general terms.
Availability and Cost in India
Certolizumab pegol is not yet commercially stocked in India the way some older biologics or Indian-made biosimilars are. It is generally accessed through named-patient import channels, where a hospital or specialty pharmacy imports a specific patient’s prescribed course from the manufacturer (UCB) or an authorised distributor, with documentation that complies with the Drugs Controller General of India’s import-for-personal-use process. In practice, this means cost is quoted case by case rather than published as a fixed price, and patients should request a specific written quote before committing, exactly as recommended in our broader psoriasis treatment cost in India guide. As a general reference point, biologics for psoriasis and psoriatic arthritis in India have been reported to range broadly from roughly ₹70,000 a month to several lakhs for a full course, depending on the specific drug, dosing protocol and import route, and newer import-only biologics in this series tend to sit toward the higher end of that range until local biosimilar competition develops.
How This Fits an Integrative, Ayurvedic Approach
In our clinical assessment, psoriasis correlates most closely with Kushta, reflecting a Vata-Kapha-Pitta imbalance addressed through the longer-term protocols described in our Ayurvedic psoriasis treatment in Bangalore guide. Pregnancy and breastfeeding add another layer of caution on the Ayurvedic side specifically: several classical internal formulations and most Panchakarma procedures, including purificatory protocols such as Virechana, are generally avoided or significantly modified during pregnancy and lactation regardless of whether a patient is also on certolizumab pegol or another biologic. This means a pregnant or breastfeeding patient managing psoriasis with an integrative approach typically needs her dermatologist or rheumatologist and her Ayurvedic physician coordinating directly, rather than running two separate, uncoordinated plans. None of this replaces either specialist: biologic therapy decisions stay with your prescribing doctor, and any Ayurvedic protocol should be adapted around your pregnancy status, not the other way round.
When to Talk to Your Doctor
If you are on certolizumab pegol, or any other TNF inhibitor, and are pregnant, planning a pregnancy, or breastfeeding, raise it with your treating doctor well before trying to conceive wherever possible, rather than waiting for a positive pregnancy test. The same applies if you are newly diagnosed with moderate-to-severe psoriasis or psoriatic arthritis during pregnancy and are weighing systemic treatment options for the first time. Never stop or switch a biologic on your own without medical guidance, since uncontrolled disease flares carry their own risks. You can also book a consultation for a personalised assessment that looks at your psoriasis or psoriatic arthritis treatment alongside your family planning and pregnancy timeline.
Frequently Asked Questions
1. Is certolizumab pegol (Cimzia) safe to use during pregnancy?
Current evidence is reassuring compared with most other biologics. Because certolizumab pegol lacks the Fc region that actively transports antibodies across the placenta, studies including the CRIB trial found no detectable drug in infants at birth in nearly all cases. Clinical consensus guidance considers it usable throughout all three trimesters, though the decision should always be individualized with your treating doctor.
2. How is certolizumab pegol different from adalimumab or etanercept?
All three are TNF-alpha inhibitors, but adalimumab is a full-length monoclonal antibody and etanercept is a receptor-fusion protein — both carry an Fc region. Certolizumab pegol is a PEGylated antibody fragment with no Fc region at all, which is why it does not cross the placenta the way the other two can, even though all three share the same broad mechanism of action.
3. How effective is certolizumab pegol for plaque psoriasis?
In the pivotal CIMPASI-1 and CIMPASI-2 trials, roughly 73% of patients on the 200 mg dose and 84% on the 400 mg dose reached PASI 75 (75% skin clearance) by week 48, with these response rates generally sustained over three years of follow-up in patients who continued treatment.
4. Is certolizumab pegol available in India?
It is not yet commercially stocked in India the way some older biologics are. It is typically accessed through named-patient import channels that comply with the Drugs Controller General of India’s import-for-personal-use process, with cost quoted on a case-by-case basis rather than published as a fixed price.
5. What are the main risks of certolizumab pegol?
As with other TNF inhibitors, the main risks are serious infections, including reactivation of latent tuberculosis, and a class-wide (though rare) risk of lymphoma and other malignancies, which is why it is not used in children. Latent TB screening is required before starting, and patients are monitored throughout treatment.
6. Can certolizumab pegol be used while breastfeeding?
Yes, based on current evidence. The CRADLE study measured drug levels in breast milk and found a median relative infant dose of about 0.125%, well under the roughly 10% threshold generally considered acceptable during lactation, with no serious adverse events reported in breastfed infants.
Sources and References
- UCB Announces the Approval of CIMZIA (certolizumab pegol) for Moderate-to-Severe Plaque Psoriasis. PR Newswire, May 2018.
- Gordon, K.B. et al., “Long-term efficacy of certolizumab pegol for the treatment of plaque psoriasis: 3-year results from two randomized phase III trials (CIMPASI-1 and CIMPASI-2),” British Journal of Dermatology, 2021.
- Certolizumab pegol for the treatment of chronic plaque psoriasis: Results through 48 weeks from 2 phase 3 trials (CIMPASI-1 and CIMPASI-2), Journal of the American Academy of Dermatology.
- Mariette, X. et al., “Lack of placental transfer of certolizumab pegol during pregnancy: results from CRIB, a prospective, postmarketing, pharmacokinetic study,” PMC / National Library of Medicine.
- Certolizumab Pegol in Plaque Psoriasis: Considerations for Pregnancy, Skin Therapy Letter (CRADLE breastfeeding study and pooled pregnancy-outcomes data).
- CIMZIA full prescribing information, U.S. FDA label, boxed warning and adverse-reaction data as summarised by Drugs.com.
- DermNet NZ and American Academy of Dermatology – TNF inhibitor and biologic therapy resources.
This article is intended for general educational purposes and does not replace personalized medical advice. Anyone considering certolizumab pegol or any other biologic, particularly during pregnancy or breastfeeding, should make that decision together with their treating dermatologist or rheumatologist.
