Add-on Treatments in Atopic Dermatitis Patients with Incomplete Response to Biologic Agents or Systemic JAK Inhibitors: A Review

Atopic dermatitis (AD) is a chronic inflammatory skin condition with a substantial impact on quality of life that often represents a challenge to control with traditional therapies. The introduction of biologic agents and systemic JAK inhibitors (JAKi) has improved therapeutic outcomes; however, many patients exhibit incomplete responses to these agents. The use of add-on strategies-such as traditional systemic drugs or phototherapy added to biologic agents or JAKi-to enhance treatment outcomes in these subsets of patients is under-explored. To assess these approaches, the authors conducted a literature review focused on add-on treatments in moderate-to-severe AD cases with incomplete responses to biologics on JAKi. Relevant studies were identified and examined, with particular attention to changes in clinical outcomes and adverse event profiles. Data limitations included variability in study designs and outcome measures. Results consistently show that add-on therapies achieve larger reductions in validated clinical scores (e.g., EASI) and higher responder rates (e.g., EASI75) than monotherapy. The use of traditional systemic agents as add-on treatment, even for a short period, can enhance partial responses to biologic agents or JAKi, leading to more effective disease control. Also, emerging data suggest that combining biologics with JAKi or vice versa may benefit patients who do not achieve adequate relief from either as monotherapy. While these findings are encouraging, several issues remain, among these the lack of large studies, the optimal timing, the cost-effectiveness, the long-term safety, and the real-world feasibility. Further well-designed clinical trials are needed to establish standardized add-on regimens, guiding clinicians toward personalized AD treatment.