JAK inhibitors have rapidly moved from investigational agents to important therapeutic options in pediatric dermatology, offering powerful control for conditions such as atopic dermatitis and alopecia areata. Yet their rising use brings practical clinical questions about patient selection, dosing, monitoring, and long‑term safety—questions that are especially urgent when treating children, whose growth and developmental trajectories must factor into every risk–benefit decision.
This article synthesizes key, practice‑focused takeaways from Dr. Yasmine Kirkorian’s presentation at the 2025 ODAC Dermatology Conference. Drawing on trial data, post‑marketing experience, and real‑world clinical judgment, it offers concise guidance on when to consider JAKs in pediatric patients, how to counsel families about realistic risks, important laboratory and safety monitoring, management of common adverse events (including “jackne” and cytopenias), and practical approaches to off‑label use and insurance challenges. The goal is to equip dermatologists and trainees with pragmatic, evidence‑informed pearls to integrate JAK therapy safely and thoughtfully into pediatric care.
Risk vs. Benefit in Pediatric Treatment
There is a constant internal dialogue in physicians between risk and benefit when choosing treatments, which is especially crucial in children with longer lifespans and unique developmental risks. Quality of life is a vital aspect of the “benefit” column and often underestimated. The risks of not treating, such as the impact of severe refractory eczema (itch, sleep loss, school difficulties) should be considered as well. Patient anxiety regarding potential risks listed in package inserts (infections, malignancy, thrombosis) needs to be addressed with realistic risk assessment.
Evolution of Risk Understanding
Looking at longer-term data for JAK inhibitors is helpful to understand real risks. Short-term data on serious adverse events like MACE and thromboembolism is reassuring, but long-term data in pediatrics is needed.
FDA Approval in Pediatrics
It is difficult to use drugs off-label, so knowing on-label options is essential. There are an increasing number of FDA-approved topical and systemic treatments for pediatric patients. The consideration of weight limits for drug approval and dosing in children is important in this population, and depending on weight, may change your available choices in treatment. There are numerous ongoing JAK inhibitor trials with decreasing age of participants, but not all young children need these treatments. If a drug is not approved for a specific pediatric condition, consider approval for other conditions, weight guidelines, and precedents for safety backing.
Adverse Effects of JAK Inhibitors
JAKs are signaling molecules with conserved functions, leading to various potential adverse effects. Different JAK selectivity can lead to different side effect profiles (e.g., lipid dysregulation with JAK1 inhibitors). Hematologic side effects are a class concern, necessitating laboratory monitoring.
Review of study analyzing adverse effect reports
Hematologic side effects were more commonly reported in children compared to adults on JAK inhibitors (not necessarily serious like lymphoma). Cutaneous side effects like acne were also more common in children. Overall, serious adverse event rates were similar to adults, which is reassuring.
“Jackne” (Acne with JAK Inhibitors)
Acne can be exacerbated, especially in teens, or a new acneiform eruption can occur. Upadacitinib is more commonly associated with this. Treatment of acne should continue if the JAK inhibitor is needed for disease remission, unless very severe.
Laboratory Monitoring
It is necessary to review label requirements for baseline and follow-up laboratory tests, which vary between different JAK inhibitors and indications. Some labels specify pregnancy testing for adolescents. Follow-up testing intervals (e.g., 4-week, 12-week) are based on clinical trial findings.
Hematologic Side Effects (Cytopenias) Management
It is important to take a history to identify other potential causes of cytopenia (e.g., viral infection, other medications). It is also crucial to obtain baseline labs to understand the patient’s normal counts before initiating the drug. Trend and repeat labs to rule out laboratory errors. For cytopenias prior to JAK initiation, consult a hematologist (often they will still allow starting the medication). For profound cytopenias, investigate underlying causes (e.g., leukemia, autoimmune disease). Package inserts provide guidance on when not to initiate and when to stop treatment based on specific cell counts.
When to Use JAK Inhibitors in Pediatric Dermatology
Dupilumab failure in atopic dermatitis is the most common scenario. Dupilumab is a well-established first-line biologic with good safety and efficacy. Dupilumab failure can be waning efficacy or, rarely, primary failure. Primary dupilumab failure may warrant consideration of JAKs after ruling out contact dermatitis and other underlying issues. Severe needle phobia in patients who cannot tolerate injectable biologics (oral JAKs may be preferable despite requiring blood tests). Concomitant systemic disease that could potentially be addressed by a JAK inhibitor (e.g., severe alopecia and atopic dermatitis, cautiously with IBD in coordination with gastroenterology) is another consideration for JAK inhibitor use. Undifferentiated inflammatory skin disease where the diagnosis is unclear despite workup and biopsies (true overlap syndromes) may also be another scenario that JAK inhibitors may be chosen.
Kids Under 12
Obtaining coverage for off-label JAK inhibitor use is very challenging. Coverage requires thorough documentation of failure of all other treatments and severe impact on quality of life (BSA, itch, sleep, hospitalizations, missed school). Drug choice often depends on insurance coverage.
Weight can influence choice due to approved weight ranges for certain JAKs. Abrocitinib is approved for weight 25 kg or more Off label, tofacitinib liquid has been used for juvenile inflammatory arthritis in patients as low as 10kg (and 2-years-old). Upadacitinib is now available in a solution and has been used in patients 10 kg or more. These liquid formulations are very important for those who cannot swallow pills or have G tubes.
Alopecia Areata
JAK inhibitors are often considered the first-line treatment, especially for severe disease (≥50% scalp loss). Ritlecitinib is FDA-approved for ages 12 and older. To increase chance of approval, severity of alopecia tool (SALT) score should be recorded in the note. There is no lower weight threshold for ritlecitinib in the package labeling. Theoretical advantages include avoiding dyslipidemia and impact on growth. Early treatment of alopecia areata is associated with better outcomes.
Impact on Growth
JAK pathways are critical for growth. There are case reports of baricitinib use correlating with growth faltering in children with rare genetic conditions. On the other hand, inflammation itself can impair growth in children with severe inflammatory conditions, so this is indeed a balance when considering JAK treatment. Another study in atopic dermatitis showed reduced linear growth but increased BMI. Post-hoc analysis of dupilumab trials suggested a rapid recapture of height acquisition with treatment, potentially allowing patients to reach their natural growth potential.
Future Priorities & Clinical Considerations
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- Duration of therapy, especially for conditions that may remit on their own.
- Ethical considerations of long-term treatment choices for children.
- Pregnancy considerations in adolescents on JAK inhibitors.
- Complex relationship between JAK inhibition, inflammation, and growth (potential for both positive and negative impacts).
This information was presented by Dr. Yasmine Kirkorian during the 2025 ODAC Dermatology Conference. The above session highlights were written and compiled by Dr. Kala Hurst.
