2026 European Expert Consensus: Prevention and Management of Amivantamab‑Induced Cutaneous Toxicities

Source: European Journal of Dermatology‑Venereology (EJDV), 2026; European Multidisciplinary Oncodermatology Expert Panel (medical oncologists, dermatologists, oncology nurses) Disclaimer: This is structured expert‑consensus excerpt for medical‑professional education only, cannot replace original full‑text guideline or clinical physician‑judgement.

Abstract

Amivantamab is a bispecific EGFR/MET antibody approved for EGFR‑mutated non‑small‑cell lung cancer. Cutaneous adverse events are very frequent, including papulopustular/acneiform eruption, xerosis, pruritus, paronychia, hair‑nail alterations, rarely severe bullous reactions. Skin toxicities may impair quality‑of‑life, cause treatment‑interruption or permanent discontinuation. This consensus provides standardized prophylaxis, grading‑oriented management, dose‑modification algorithm, multidisciplinary workflow and special‑population recommendations for daily‑practice. CTCAE v5.0 is adopted for toxicity gradingsms.carm.e....

1 Spectrum & Clinical Characteristics of Amivantamab‑related Skin Toxicities

1. Papulopustular (acneiform) eruption: Most‑common; median onset 1‑3 weeks after initiation; predilection for face, scalp, upper trunk; scalp‑involvement is frequent. Higher incidence when combined with lazertinibPMC.
2. Xerosis (dry skin) & pruritus: May persist throughout treatment course.
3. Nail‑apparatus toxicities: Paronychia, pyogenic granuloma‑like lesions, nail dystrophy; usually occur ≥ 8 weeks after starting therapyPMC.
4. Rare severe cutaneous adverse reactions (SCARs): SJS‑TEN, erythema multiforme; require immediate drug‑withdrawal.

Key message: Skin events are more rapid‑onset and sometimes more severe than conventional EGFR‑TKI‑related dermatitis, especially in combination‑regimensPMC.

2 Pre‑Treatment Risk Assessment & Baseline Evaluation

1. Baseline skin‑nail examination; document pre‑existing acne, paronychia, atopic dermatitis, skin barrier damage.
2. Drug‑history: tetracycline contraindications (pregnancy, children < 8 years, hypersensitivity).
3. Patient education: written material; inform patients of early‑warning signs (blistering, mucosal erosion, progressive painful swelling of nail folds).
4. Multidisciplinary suggestion: early‑oncodermatology consultation for high‑risk patients (prior severe EGFR‑agent skin toxicity, severe atopy)PMC.

3 Primary Prophylaxis (start on Day 1 of amivantamab, consensus strong recommendation)

3.1 Skin barrier & photoprotection

• Emollient: non‑comedogenic, ceramide‑rich fragrance‑free moisturizer applied full‑body (except scalp) throughout treatment; avoid hot water, harsh soap, alcohol‑containing topical‑productselectronic....
• Photoprotection: broad‑spectrum UVA‑UVB sunscreen + physical sun‑protection; continue for 2 months after last amivantamab dose; strict sun‑avoidance.
• Hands‑feet hygiene: chlorhexidine‑based washing for nail‑fold prophylaxis to reduce paronychia riskelectronic....

3.2 Pharmacologic prophylaxis

1. Oral tetracycline‑class: doxycycline 100 mg twice daily / minocycline 100 mg twice daily, for first 12 weeks of therapy, if no contraindicationselectronic....
   • Contra‑population: pregnancy, breastfeeding, children < 8 y.
2. After stopping oral tetracyclines: 1 % clindamycin lotion for scalp prophylaxis, continue up to 9 months, for scalp‑predominant toxicity preventionelectronic....
3. Conditional: zinc supplementation may be considered for patients with documented zinc‑deficiency (weak‑evidence)PMC.

Two‑practice‑models accepted in Europe: universal‑prophylaxis (preferred by consensus panel) vs watch‑and‑treat for selected low‑risk patients.

4 Graded‑Management Algorithm (CTCAE v5.0)

4.1 Grade 1 (papulopustular < 10 % BSA; mild xerosis/pruritus; grade 1 paronychia)

• Supportive skin‑care; topical low‑potency corticosteroids; topical clindamycin 1 % lotion/gel.
• Paronychia: antiseptic soaks, topical antiseptic; no dose‑adjustment of amivantamab.
• Follow‑up within 1‑2 weeks.

4.2 Grade 2 (10‑30 % BSA, moderate symptoms; paronychia with local infection‑signs)

• Continue emollient & photoprotection.
• Oral tetracycline (if‑not‑already‑on‑prophylaxis); topical corticosteroids (mid‑high potency for trunk/scalp, low‑potency for face).
• For paronychia: topical antibiotic‑antifungal agents; systemic antibiotics if bacterial‑superinfection.
• Oncologic‑drug‑adjustment: maintain amivantamab; re‑assess in 2 weeks; if no improvement, perform dose‑reduction. Refer to dermatology.

4.3 Grade 3 (> 30 % BSA; severe pain/pruritus; ADL‑impairment; extensive paronychia/pyogenic granuloma)

• Hold amivantamab; full dermatology referral; bacterial culture if purulence present.
• Systemic tetracycline ± short‑course oral corticosteroids; optimized topical regimen.
• When improved to ≤ Grade 2: resume amivantamab at reduced‑dose‑level.
• If no improvement after 14 days: permanent discontinuation.

4.4 Grade 4 / Severe Bullous‑Mucosal Reaction (SJS/TEN, extensive blister, mucosal erosion)

• Permanent discontinuation of amivantamab immediately.
• Urgent dermatology‑emergency‑care; systemic‑supportive‑management.

5 Management for Special‑Pattern Skin Toxicities

1. Severe scalp‑predominant eruption: topical clindamycin lotion, scalp‑suitable corticosteroid‑solution; avoid oily comedogenic scalp‑products.
2. Paronychia & pyogenic granuloma: antiseptic soak; topical steroids / calcineurin‑inhibitors; bacterial/fungal topical agents; oral antibiotics for spreading infection; cautery for persistent pyogenic granuloma‑lesions. Avoid aggressive nail‑manipulation.
3. Isolated severe xerosis‑pruritus: urea‑containing emollients; oral antihistamines for pruritus; short‑term topical‑steroids.

6 Dose‑Modification Principles (aligned with European label + consensus)

• Skin toxicity‑driven dose‑reduction is permitted; do not arbitrarily discontinue effective anti‑tumor‑therapy without multidisciplinary discussion.
• After resolution, step‑down to lower‑dose tier; do not routinely attempt to re‑escalate back to original‑dose after grade 3 event.
• Permanent discontinuation: grade 4 reaction; grade 3 non‑responsive to maximal‑medical‑therapy within 14 days; recurrent grade 3 despite dose‑reduction.

7 Special‑Populations

1. Pregnancy / lactation: tetracyclines contra‑indicated; rely solely on non‑pharmacologic skin‑care and topical‑therapy; oncologic‑drug decision‑making by tumour‑board.
2. Children: limited real‑world‑data; tetracyclines contra‑indicated < 8 years‑old.
3. Pre‑existing severe atopic dermatitis: enhanced baseline‑barrier‑repair; early‑dermatology‑co‑management.

8 Core Consensus Take‑Home Messages

1. Universal skin‑toxicity prophylaxis starting on Day 1 is recommended for amivantamab‑treated patients (doxycycline/minocycline + standardized skin‑care + photoprotection)electronic....
2. Scalp‑involvement is frequent; maintain scalp‑targeted topical prophylaxis after oral‑tetracycline completion.
3. Manage strictly per CTCAE v5.0 grading; grade 3 events mandate drug‑hold and dermatology referral.
4. Bullous/mucosal‑severe‑reaction = immediate permanent discontinuation.
5. Multidisciplinary oncologist‑oncodermatology collaboration reduces unnecessary treatment‑discontinuation and optimizes patient‑outcomes.

Note: For medical‑professional study only, not for direct clinical replacement