Dermatology TextbookSkin reactions and interactionsBiologics

Biologic Therapies in Dermatology

Introduction

Biologic therapies have revolutionized the treatment of inflammatory skin diseases by targeting specific cytokines, receptors, and immune cell populations. Unlike traditional immunosuppressants that broadly suppress immune function, biologics offer precise modulation of pathogenic pathways with often superior efficacy and improved safety profiles.

This chapter provides a comprehensive overview of biologic agents used in dermatology, organized by mechanism of action.


Overview of Biologic Classes

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TNF-α Inhibitors

Mechanism and Agents

AgentStructureHalf-lifeApproved Indications (Derm)
EtanerceptFusion protein (TNFR2-Fc)3-5.5 daysPsoriasis, psoriatic arthritis
InfliximabChimeric mAb8-10 daysPsoriasis, psoriatic arthritis
AdalimumabFully human mAb14 daysPsoriasis, PsA, HS, pyoderma gangrenosum
CertolizumabPEGylated Fab'14 daysPsoriasis, PsA (no placental transfer)
GolimumabHuman mAb14 daysPsoriatic arthritis

TNF-α in Psoriasis

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Safety Considerations

RiskMonitoring
Infections (esp. TB, fungal)TB screening before and during; watch for signs
Malignancy (lymphoma)Baseline and ongoing assessment
Heart failureContraindicated in NYHA III/IV
Demyelinating diseaseRare; avoid in MS history
Injection site reactionsCommon with SC agents
Autoantibody formationANA, anti-dsDNA (usually asymptomatic)

IL-17 Inhibitors

Agents and Targets

AgentTargetStructureIndications
SecukinumabIL-17AHuman mAbPsoriasis, PsA, AS
IxekizumabIL-17AHumanized mAbPsoriasis, PsA
BrodalumabIL-17RAHuman mAbPsoriasis
BimekizumabIL-17A + IL-17FHumanized mAbPsoriasis, PsA, HS

IL-17 in Psoriasis

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Clinical Considerations

IssueDetails
EfficacyPASI 90+ in >70% (among highest for psoriasis)
CandidiasisIncreased risk (mucocutaneous); usually mild
IBDNew-onset or exacerbation (esp. brodalumab)
Suicidal ideationBoxed warning for brodalumab
Speed of responseRapid onset (visible improvement in 2-4 weeks)

IL-23 Inhibitors

Agents

AgentTargetStructureDosing
UstekinumabIL-12/23 (p40 subunit)Human mAbQ12 weeks (after loading)
GuselkumabIL-23 (p19 subunit)Human mAbQ8 weeks
TildrakizumabIL-23 (p19 subunit)Humanized mAbQ12 weeks
RisankizumabIL-23 (p19 subunit)Humanized mAbQ12 weeks

IL-23/IL-17 Axis

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Advantages of IL-23 Inhibitors

FeatureBenefit
DurabilitySome patients maintain response after discontinuation
Dosing intervalQ8-12 weeks maintenance (convenient)
Safety profileGenerally excellent; no TB reactivation signal
IBDNo increased risk (unlike IL-17 inhibitors)
EfficacyPASI 90+ in 70-80%

IL-4/IL-13 Inhibitors (Type 2 Targeting)

Dupilumab: Breakthrough for AD

FeatureDetails
TargetIL-4Rα (blocks IL-4 and IL-13)
StructureFully human mAb
Approved indicationsAtopic dermatitis, asthma, CRSwNP, eosinophilic esophagitis, prurigo nodularis
Dosing300 mg SC q2 weeks

Mechanism in Atopic Dermatitis

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Other Type 2 Agents

AgentTargetStatus
TralokinumabIL-13 onlyApproved for AD
LebrikizumabIL-13 onlyApproved for AD
NemolizumabIL-31RAApproved for prurigo nodularis, AD

Dupilumab Adverse Effects

EffectFrequencyNotes
Conjunctivitis10-30% in ADLess in asthma; mechanism unclear
Injection site reactionsCommonUsually mild
Facial erythemaUncommon"Dupilumab facial redness"
InfectionsNo significant increase
EosinophiliaTransientUsually asymptomatic

Anti-CD20: B Cell Depletion

Rituximab in Dermatology

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Indications in Dermatology

DiseaseEvidenceTypical Regimen
Pemphigus vulgarisFirst-line with CS1g × 2 (days 1, 15)
Pemphigus foliaceusFirst-lineSame
Bullous pemphigoid (refractory)Second-lineSame
Dermatomyositis (refractory)Case series375 mg/m² × 4
Primary cutaneous B cell lymphomasStandardVarious regimens

Anti-IgE: Omalizumab

Mechanism

FeatureDetails
TargetIgE (Fc portion)
EffectBinds free IgE; prevents binding to FcεRI
ResultReduces IgE, downregulates FcεRI on mast cells/basophils

Indications in Dermatology

ConditionEvidenceMechanism
Chronic spontaneous urticariaHighReduces IgE autoantibodies, FcεRI activation
Chronic inducible urticariaModerateSame
Refractory atopic dermatitisLimitedIgE reduction

JAK Inhibitors (Targeted Synthetic)

Overview

JAK inhibitors are small molecules (not biologics) but target specific pathways similarly.

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JAK Inhibitors in Dermatology

AgentTargetIndicationRoute
TofacitinibJAK1/3Psoriasis, PsA, off-label (AA, vitiligo)Oral
BaricitinibJAK1/2Atopic dermatitis, AAOral
UpadacitinibJAK1Atopic dermatitisOral
AbrocitinibJAK1Atopic dermatitisOral
RuxolitinibJAK1/2Atopic dermatitis, vitiligoTopical
DeucravacitinibTYK2PsoriasisOral

Summary: Biologic Selection by Disease

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Key Clinical Pearls

TopicPearl
IL-17 inhibitorsHighest PASI rates; watch for candidiasis and IBD
IL-23 inhibitorsConvenient dosing (q8-12 weeks); durable response
DupilumabGame-changer for AD; watch for conjunctivitis
RituximabFirst-line for pemphigus with corticosteroids
OmalizumabWorks in CSU regardless of IgE level
JAK inhibitorsOral convenience; monitor for infections, VTE, malignancy
TB screeningRequired before anti-TNF; consider for all biologics

Cross-References

How to Cite

Cutisight. "Biologic Therapies." Encyclopedia of Dermatology [Internet]. 2026. Available from: https://cutisight.com/education/volume-03-skin-reactions-and-interactions/04-immunology/04-therapeutics/01-biologics/01-biologic-therapies

This is an open-access resource. Please cite appropriately when using in academic or clinical work.