Adverse Effects of Biologic Therapy: A Retrospective Cohort Study

Objective: To evaluate adverse effects associated with biologic therapy (Etanercept, Adalimumab, and Secukinumab) in patients with psoriasis, psoriatic arthritis, and hidradenitis suppurativa. Methods: This retrospective observational study included 58 patients receiving biologic therapy: 40 with generalized plaque psoriasis, 13 with psoriatic arthritis, and 3 with hidradenitis suppurativa. Eligibility was based on national treatment protocols (Psoriasis Area and Severity Index [PASI] > 10; Hurley stage II–III). Demographic data, treatment duration, therapy modifications, discontinuations, and adverse events were collected from medical records. Patients were monitored for both efficacy and safety outcomes. Results: Treatment discontinuation due to severe hepatotoxicity occurred in four patients (three receiving Etanercept and one Adalimumab), corresponding to 6.9% of the cohort. Adalimumab was discontinued in one patient due to cutaneous leishmaniasis after 24 months and in another due to pregnancy after 26 months. Upper limb edema was observed following a switch from Adalimumab to Secukinumab. One patient discontinued Etanercept due to lack of efficacy and subsequently died from a fatal methotrexate overdose. Treatment switches included Etanercept to Adalimumab for granulomatous uveitis (one case) and Adalimumab to Etanercept due to generalized urticaria (two cases). Conclusion: Adverse events were relatively infrequent, with an overall incidence below 10% (6.9% for the most common event and <2% for other events). Most adverse events were mild and reversible following dose adjustment or temporary discontinuation. No unexpected or fatal adverse events were directly attributable to biologic therapy.