FDA Approved · October 2023
IL-17A & F Inhibitor · Dermatology · Plaque Psoriasis
âš SI/B Warning
Bimekizumab
BIMZELX® · UCB, Inc.
A humanized IgG1 monoclonal antibody that selectively inhibits both interleukin-17A (IL-17A) and interleukin-17F (IL-17F) — the first dual IL-17A/F inhibitor approved by the FDA. Indicated for the treatment of moderate to severe plaque psoriasis in adults who are candidates for systemic therapy or phototherapy.
Drug Overview
Indication
Moderate-Severe Plaque Psoriasis
Adults eligible for systemic therapy or phototherapy
Mechanism
Dual IL-17A & IL-17F Inhibitor
First-in-class dual IL-17 inhibitor
Approved Dose
320 mg SC
Wks 0,4,8,12,16 → Q8W
EU Approval
Aug 2023
European Commission
Mechanism of Action
Bimekizumab-bkzx is a humanized IgG1/κ monoclonal antibody with two identical antigen-binding regions that selectively bind to human interleukin-17A (IL-17A), interleukin-17F (IL-17F), and interleukin-17AF heterodimer cytokines, inhibiting their interaction with the IL-17 receptor complex.
IL-17A and IL-17F are naturally occurring cytokines involved in normal inflammatory and immune responses. Elevated levels of both are found in lesional psoriatic skin. Unlike IL-17A-only inhibitors (secukinumab, ixekizumab), bimekizumab uniquely neutralizes both IL-17A and IL-17F, which may contribute to its high rates of complete skin clearance. Bimekizumab inhibits the release of proinflammatory cytokines and chemokines.
Competitive Landscape
| Drug | Target | Route | Approval | PASI 90 (vs placebo) |
|---|---|---|---|---|
| Secukinumab (COSENTYX) | IL-17A | SC | 2015 | ~75% vs 3–4% |
| Ixekizumab (TALTZ) | IL-17A | SC | 2016 | ~70% vs 3% |
| Brodalumab (SILIQ) | IL-17RA | SC | 2017 | ~83% vs 3% |
| Guselkumab (TREMFYA) | IL-23 | SC | 2017 | ~73% vs 3% |
| Risankizumab (SKYRIZI) | IL-23p19 | SC | 2019 | ~72% vs 2% |
| Bimekizumab (BIMZELX) ▶ | IL-17A + IL-17F | SC | Oct 2023 | 85–91% vs 1–5% |
Key Drug Information
| Parameter | Detail |
|---|---|
| Proprietary Name | BIMZELX® |
| INN / Generic Name | Bimekizumab-bkzx |
| Code Name | UCB4940 (CDP4940) |
| Sponsor / Manufacturer | UCB, Inc. · 1950 Lake Park Drive, Smyrna, GA 30080 · US License No. 1736 |
| Pharmacologic Class | Humanized interleukin-17A and F antagonist (IgG1 monoclonal antibody) |
| Molecular Weight | ~150 kDa |
| Production | Recombinant DNA technology in Chinese Hamster Ovary (CHO) cells |
| Dosage Forms | 160 mg/mL in single-dose prefilled syringe or single-dose prefilled autoinjector (1 mL) |
| NDC | 50474-781-85 (autoinjector carton, 2×160 mg) · 50474-780-79 (prefilled syringe carton, 2×160 mg) |
| Inactive Ingredients | Glacial acetic acid, glycine, polysorbate 80, sodium acetate, Water for Injection USP (pH 5.1) |
| Storage | Refrigerated 2°C–8°C. May store at room temp ≤25°C for up to 30 days in original carton. Do not freeze or shake. |
| PI Revision Date | October 2023 |
Clinical Efficacy
Co-Primary Endpoints
IGA 0/1 & PASI 90
at Week 16
at Week 16
≥2-grade improvement from baseline
Trial Design
RCT, DB, Multi-arm
Placebo + active comparators
Pivotal Trials
3
Ps-1 (vs UST) · Ps-2 (vs PBO) · Ps-3 (vs ADA)
Total Subjects
1,480
Phase 3 (Ps-1, Ps-2, Ps-3)
Co-Primary Endpoint Results at Week 16
Trial Ps-1 (PS0009) · NCT03370133 · Phase 3 Pivotal
Adults ≥18 yrs · N=567 · Active comparator: Ustekinumab · Co-primary endpoints: IGA 0/1 & PASI 90 at Week 16
IGA 0 or 1 (“Clear” or “Almost Clear”) at Week 16
BIMZELX 320 mg Q4W (N=321)
84%
Placebo (N=83)
5%
PASI 90 at Week 16
BIMZELX 320 mg Q4W (N=321)
85%
Placebo (N=83)
5%
Trial Ps-2 (PS0013) · NCT03410992 · Phase 3 Pivotal
Adults ≥18 yrs · N=435 · Placebo-controlled · Randomized withdrawal at Week 16 for PASI 90 responders
IGA 0 or 1 at Week 16
BIMZELX 320 mg Q4W (N=349)
93%
Placebo (N=86)
1%
PASI 90 at Week 16
BIMZELX 320 mg Q4W (N=349)
91%
Placebo (N=86)
1%
Secondary Endpoints at Week 16 (Trials Ps-1 & Ps-2)
| Endpoint | Ps-1 BIMZELX | Ps-1 Placebo | Ps-2 BIMZELX | Ps-2 Placebo |
|---|---|---|---|---|
| IGA 0 (“Clear”) | 59% | 0% | 70% | 1% |
| PASI 100 (Complete clearance) | 59% | 0% | 68% | 1% |
| PASI 75 at Week 4 | 77% | 2% | 76% | 1% |
| Scalp IGA 0/1 at Week 16 | 84% (240/285) | 15% (11/72) | 92% (286/310) | 7% (5/74) |
All secondary endpoints were statistically superior to placebo (p <0.001) in both trials. Subgroup analyses by age, gender, race, baseline IGA score, and prior biologic therapy showed consistent responses.
Efficacy Across Endpoints — Week 16 Visual Summary
BIMZELX vs Placebo — Response Rates at Week 16 (Pooled Ps-1 & Ps-2)
Co-primary and key secondary endpoints · Source: FDA Prescribing Information Table 2, Ref ID 5262329
Data from Trial Ps-1 (N=321 BIMZELX, N=83 placebo) and Trial Ps-2 (N=349 BIMZELX, N=86 placebo). Values shown are for individual trials.
Maintenance of Response — Week 56 (Trial Ps-2 Randomized Withdrawal)
PASI 90 responders at Week 16 were re-randomized to BIMZELX Q4W, BIMZELX Q8W, or placebo (withdrawal). At Week 56: 91% Q4W and 87% Q8W maintained PASI 90, vs 16% placebo. IGA 0/1 maintenance: 90% Q4W, 87% Q8W, vs 24% placebo. Median time to loss of PASI 90 or IGA 0/1 response after withdrawal: ~24 weeks.
PASI 90 Maintenance Through Week 56 — Randomized Withdrawal Period (Trial Ps-2)
After re-randomization of PASI 90 responders at Week 16 · Digitized from FDA PI Figure 2
Source: FDA Prescribing Information NDA/BLA 761151 (Ref ID 5262329). Values digitized from Figure 2.
Active-Comparator Head-to-Head Data
| Trial | Comparator | BIMZELX PASI 90 | Comparator PASI 90 | Significance |
|---|---|---|---|---|
| Ps-1 (NCT03370133) | Ustekinumab (45 mg or 90 mg) | 85% at Wk 16 | ~50% at Wk 16 | Superior |
| Ps-3 (NCT03412747) | Adalimumab (80 mg then 40 mg Q2W) | ~86% at Wk 16 | ~48% at Wk 16 | Superior |
| Ps-4 (PS0015) | Secukinumab 300 mg | ~86% at Wk 16 | ~70% at Wk 16 | Superior |
Safety & Adverse Drug Reactions
Warnings and Precautions
âš Warnings and Precautions
- Suicidal Ideation and Behavior (SI/B): May increase risk. Monitor for emergence or worsening of depression, suicidal ideation, or mood changes. Call National Suicide and Crisis Lifeline at 988 if changes occur.
- Serious Infections: May increase risk. Do not administer until active infection resolves.
- Tuberculosis: Evaluate before treatment. Avoid in active TB. Initiate treatment of latent TB prior to use.
- Liver Biochemical Abnormalities: Test liver enzymes at baseline and periodically. Permanently discontinue if causally associated combined transaminase/bilirubin elevations occur.
- Inflammatory Bowel Disease: Avoid in active IBD. Monitor for new or worsening IBD symptoms.
Total Subjects Treated
1,789
Across all BIMZELX trials
≥1 Year Exposure
1,073
Subjects exposed ≥52 weeks
Infection Rate (16 wk)
36%
vs 23% placebo
Oral Candidiasis
9%
vs 0% placebo — key signal
âš Suicidal Ideation and Behavior (SI/B): Pooled analysis of 16-week placebo-controlled data showed 12/670 (1.8%) BIMZELX-treated subjects vs 1/169 (0.6%) placebo-treated subjects reported passive suicidal ideation (estimated relative risk 3.0; 95% CI: 0.39, 22.74). One completed suicide occurred in the open-label extension after 718 days of treatment. Three suicide attempts were also reported. A causal association has not been established. Prescribers should weigh risks and benefits in patients with history of severe depression or SI/B.
Adverse Reactions ≥1% — 16-Week Controlled Data (Trials Ps-1 & Ps-2)
| Adverse Reaction | BIMZELX 320 mg (N=670) | Placebo (N=169) |
|---|---|---|
| Upper Respiratory Tract Infections | 102 (15%) | 24 (14%) |
| Oral Candidiasis | 61 (9%) | 0 (0%) |
| Headache | 22 (3%) | 0 (0%) |
| Injection Site Reactions | 19 (3%) | 2 (1%) |
| Tinea Infections | 18 (3%) | 1 (1%) |
| Gastroenteritis | 12 (2%) | 0 (0%) |
| Herpes Simplex Infections | 9 (1%) | 0 (0%) |
| Acne | 8 (1%) | 0 (0%) |
| Folliculitis | 8 (1%) | 0 (0%) |
| Other Candida Infections | 7 (1%) | 1 (1%) |
| Fatigue | 7 (1%) | 0 (0%) |
Less common (<1% but >0.1%) reactions more frequent with BIMZELX than placebo: neutropenia, eczema, otitis externa, otitis media, pyrexia.
Key Safety Signals
Suicidal Ideation / Behavior
1.8% vs 0.6% placebo
Passive SI on C-SSRS; 1 completed suicide (OLE); 3 attempts. RR ~3.0. Warning in labeling.
Oral Candidiasis
9% vs 0% placebo
Most common unique signal. Includes oral, oropharyngeal, fungal pharyngitis. Generally manageable.
Liver Enzyme Elevations
1.0% vs 0.6% placebo
Transaminases >3× ULN. Time to onset: 28–198 days. Resolved after discontinuation. Monitor at baseline and periodically.
Infections (all)
36% vs 23% placebo
141.7 vs 84.6 per 100 PY. Serious infections: 0.3% vs 0% placebo. Long-term: 63% (120.4 per 100 PY).
Inflammatory Bowel Disease
0.12 per 100 PY
7 adjudicated new IBD cases in 2,480 subjects (5,830 PY). Majority serious; most required treatment discontinuation.
Cardiac Safety
No MACE signal
No increase in major adverse cardiovascular events vs placebo or active comparators across trials.
Immunogenicity (ADA)
45% ADA rate
116/257 subjects developed anti-bimekizumab antibodies (52–56 wk); ~16% neutralizing. No identified clinical impact on safety or efficacy.
Malignancy
No increased risk
No increased malignancy risk vs placebo or active comparators in controlled trials.
Long-Term Safety (Weeks 56–128, Open-Label Extension)
Through Week 128, no new adverse reactions beyond those identified in the initial 16-week period were identified — except for suicide attempts and completed suicide occurring in the OLE. Through Week 144 (Trial Ps-4, 691 subjects), no new adverse reactions were identified.
Use in Special Populations
| Population | Summary |
|---|---|
| Pregnancy | Insufficient human data. No adverse developmental effects in cynomolgus monkeys up to 38× MRHD (50 mg/kg/week SC). IgG crosses placenta — delay live vaccines in infants exposed in utero (consider ≥4 months after birth). Pregnancy registry: 1-877-311-8972. |
| Lactation | No data in human or animal milk. Endogenous IgG transferred in human milk. Benefits of breastfeeding should be considered alongside risks. |
| Pediatric | Safety and effectiveness not established in pediatric patients. |
| Geriatric (≥65 yr) | 153/1,789 subjects were ≥65 years; 18 were ≥75 years. No differences in safety or effectiveness observed, but numbers insufficient for definitive conclusions. |
| High Body Weight (≥120 kg) | Average plasma concentrations ~30% lower in subjects ≥120 kg vs <120 kg. Consider 320 mg Q4W (instead of Q8W) after Week 16 in patients ≥120 kg. |
Pharmacology & Pharmacokinetics
Mechanism of Action
Bimekizumab-bkzx selectively binds and neutralizes IL-17A, IL-17F, and the IL-17AF heterodimer, preventing their interaction with the IL-17 receptor complex. Both IL-17A and IL-17F are involved in psoriasis pathogenesis — they are elevated in psoriatic lesions and drive keratinocyte activation, neutrophil recruitment, and production of proinflammatory mediators. Dual neutralization of both cytokines may provide greater suppression of the psoriatic inflammatory cascade compared to IL-17A-only inhibitors.
Pharmacokinetic Parameters
Peak Concentration (Cmax)
25 μg/mL
Median (range 12–50 μg/mL); reached in 3–4 days
Bioavailability
70%
Absolute bioavailability in healthy subjects (SC)
Volume of Distribution
11.2 L
Median Vss at steady state
Half-Life
23 days
Mean terminal elimination t½
Clearance (CL/F)
0.337 L/day
Median; dose-independent clearance
PK Linearity
Dose-proportional
64–480 mg range (0.2–1.5× approved dose)
Metabolism & Excretion
Bimekizumab-bkzx is expected to be degraded into small peptides by catabolic pathways, consistent with other IgG1 monoclonal antibodies. No dedicated hepatic or renal metabolism studies are required for large biologics of this class.
Drug Interactions
CYP450 Interaction: Formation of CYP450 enzymes can be altered by increased cytokine levels (IL-1, IL-6, IL-10, TNFα, IFN) during chronic inflammation. Initiation or discontinuation of BIMZELX may modulate serum cytokine levels. For patients on narrow therapeutic index CYP450 substrates (e.g., warfarin, cyclosporine), consider monitoring drug effect or concentration and adjusting dose of the CYP450 substrate as needed.
Pharmacodynamics
Elevated levels of IL-17A and IL-17F are found in lesional psoriatic skin. Bimekizumab exposure-response relationships to serum biomarkers (including IL-17A and IL-17F) and the time course of pharmacodynamic responses are not fully characterized.
Immune Response to Inactivated Vaccines: Healthy subjects who received a single 320 mg dose of BIMZELX 2 weeks prior to inactivated seasonal influenza vaccination had similar antibody responses compared to unvaccinated controls. Avoid live vaccines during BIMZELX treatment.
Body Weight Effect
In subjects weighing ≥120 kg, average plasma concentrations of bimekizumab are predicted to be at least 30% lower than in those weighing <120 kg (median 87 kg). This is why dosing guidance recommends considering 320 mg Q4W after Week 16 for patients ≥120 kg.
Dosing & Administration
Approved Dose
320 mg SC
Two 160 mg injections per dose
Route
Subcutaneous
Thigh, abdomen, or back of upper arm
Contraindications
None
Warnings & precautions apply
Dosing Schedule
| Period | Dose | Frequency | Notes |
|---|---|---|---|
| Induction (Weeks 0–16) | 320 mg (2 × 160 mg SC) | Q4W: Weeks 0, 4, 8, 12, 16 | Two injections at different anatomical sites per dose |
| Maintenance (after Week 16) | 320 mg | Every 8 weeks (Q8W) | Standard maintenance dose |
| High body weight (≥120 kg) | 320 mg | Consider Q4W after Week 16 | Plasma concentrations ~30% lower in ≥120 kg patients |
| Missed dose | 320 mg | Administer as soon as possible | Resume regular schedule thereafter |
Pre-Treatment Evaluations Required
Tuberculosis
Evaluate before initiating
Avoid in active TB. Treat latent TB before starting BIMZELX. Consider anti-TB therapy if adequate prior treatment cannot be confirmed.
Liver Enzymes
Baseline LFTs required
Test liver enzymes, alkaline phosphatase, and bilirubin at baseline and periodically during treatment.
Vaccinations
Complete before starting
Complete all age-appropriate vaccinations before treatment. Avoid live vaccines during BIMZELX therapy.
Psychiatric History
Assess SI/B history
Weigh risks and benefits in patients with history of severe depression or suicidal ideation/behavior.
Administration Instructions
| Parameter | Instruction |
|---|---|
| Preparation | Remove from refrigerator 30–45 minutes before injection to reach room temperature (protects from light in original carton) |
| Injection sites | Thigh, abdomen (not within 2 inches of navel), or back of upper arm (HCP/caregiver only) |
| Avoid injecting into | Tender, bruised, red, hard, thick, scaly skin or areas affected by psoriasis |
| Site rotation | Different anatomical locations for each of the two 160 mg injections per dose; alternate sites each administration |
| Self-injection | Patients may self-inject after proper training in subcutaneous injection technique by a healthcare professional |
| Syringe/autoinjector disposal | Discard in FDA-cleared sharps container immediately after use. Do not reuse. |
Contraindications
None. BIMZELX has no identified contraindications per the approved prescribing information. Warnings and precautions (SI/B, infections, TB, liver enzyme abnormalities, IBD) apply.
Regulatory History
BLA 761151 — Key Facts
| Parameter | Detail |
|---|---|
| Application Number | BLA 761151 |
| Application Type | BLA (Resubmission after Complete Response) · Standard review |
| Sponsor | UCB, Inc. |
| Code Name | UCB4940 (CDP4940) |
| Original BLA Submission | July 15, 2020 |
| Complete Response Letter | May 12, 2022 (GMP deficiencies at UCB Braine facility) |
| BLA Resubmission Date | November 21, 2022 |
| PDUFA Goal Date | May 21, 2023 |
| Review Completion Date | October 16, 2023 |
| FDA Approval Date | October 2023 |
| Review Division | Division of Dermatology and Dentistry / Office of Immunology and Inflammation |
| Medical Review Ref ID | 5261174 (resubmission) · 4982337 (original) |
| PI Ref ID | 5262329 |
| EU Approval | August 2023 — European Commission |
Regulatory Timeline
~2014–2018
Phase 1 & Phase 2 Development
Phase 1 first-in-human and dose-ranging trials (PS0010, PS0011, PS0016, PS0018). Dose-response established for 320 mg Q4W as the Phase 3 dose.
2018–2020
Phase 3 Pivotal Trials Conducted
Trial Ps-1 (NCT03370133, vs ustekinumab), Trial Ps-2 (NCT03410992, vs placebo with randomized withdrawal), and Trial Ps-3 (NCT03412747, vs adalimumab) — all met co-primary endpoints of IGA 0/1 and PASI 90 at Week 16.
July 15, 2020
Original BLA 761151 Submitted
UCB submits original BLA for BIMZELX for moderate to severe plaque psoriasis in adults.
May 12, 2022
Complete Response Letter (CRL) Issued
FDA issued CRL due to Good Manufacturing Practice (GMP) deficiencies identified at UCB Braine Drug Product Manufacturing Facility (FEI: 3003909356) by OPMA/DBM. Product not approvable until GMP issues resolved.
August 17, 2022
Type A End of Review Meeting
FDA agreed applicant’s proposed data package for GMP remediation appeared adequate. UCB also proposed to include new safety data from OLE trial PS0014 and new Phase 3b trial PS0015 (vs secukinumab).
November 21, 2022
BLA Resubmission Filed
Class 2 resubmission addressing GMP deficiencies. Included new safety data from PS0014 (OLE, 1,343 subjects) and PS0015 (vs secukinumab, 743 subjects), triggering new SI/B safety review.
2023 (June–July)
SI/B Safety Review — REMS Oversight Committee & MPPRC
New completed suicide and 3 suicide attempts from OLE data prompted re-evaluation. REMS Oversight Committee meetings (June 2 & 13, 2023) and Medical Policy & Program Review Council (July 19, 2023) advised on SI/B risk communication in labeling. REMS not required; Warnings & Precautions and Medication Guide approach adopted.
October 2023
FDA Approval — BIMZELX® (bimekizumab-bkzx)
Approved for the treatment of moderate to severe plaque psoriasis in adults who are candidates for systemic therapy or phototherapy. SI/B risk conveyed in Warnings & Precautions and Medication Guide. No boxed warning; no contraindications.
FDA Review Assessment
The review team concluded that the benefit-risk of bimekizumab is favorable in the proposed population with appropriate labeling and recommended approval. The application demonstrated substantial evidence of effectiveness through three pivotal Phase 3 trials showing bimekizumab was statistically superior to placebo and numerically superior to ustekinumab and adalimumab on co-primary endpoints of PASI 90 and IGA 0/1 at Week 16. The potential risk of SI/B is adequately described in product labeling (Warnings and Precautions, Section 6, Section 17, and Medication Guide).
Post-Marketing Requirements
| Requirement | Detail |
|---|---|
| Suicidal Ideation Pharmacovigilance | Ongoing monitoring of SI/B through post-marketing surveillance. Updated labeling and Medication Guide to communicate risk. |
| Pediatric Studies | Safety and efficacy not established in pediatric patients; data required per PREA. |
| Pregnancy Registry | OTIS AutoImmune Diseases Study — 1-877-311-8972 or mothertobaby.org/pregnancy-studies/ |
| Long-term Liver Safety | Continued monitoring and reporting of liver biochemical abnormalities per routine pharmacovigilance. |
Data sourced from: FDA Prescribing Information for BIMZELX (bimekizumab-bkzx) — BLA 761151 (Ref ID: 5262329, revised 10/2023) and FDA BLA Multi-Disciplinary Review and Evaluation — BLA 761151 (Ref IDs: 5261174 & 4982337, review completed October 16, 2023).
For investigational and educational purposes only. Not for clinical decision-making.
© 2026 TrialistMD · All rights reserved
For investigational and educational purposes only. Not for clinical decision-making.
© 2026 TrialistMD · All rights reserved
