Characteristics of anti-IL-17/23 biologics-induced interstitial pneumonia in patients with psoriasis

Objectives Anti-IL-17/23 biologics are increasingly used to treat psoriasis. We aimed to elucidate characteristics of drug-induced interstitial pneumonia (DIIP) caused by anti-IL-17/23 biologics. Methods We retrospectively analyzed the clinical data of psoriasis patients treated with anti-IL-17/23 biologics. Chest CT was performed to evaluate DIIP. Serum KL-6 levels were measured before treatment (baseline) and during treatment. Results A total of 603 psoriasis patients were treated with anti-IL-17/23 biologics with mean follow-up of 21.1 months. Six patients developed DIIP at mean 14 months after initiation of the therapy. Older age, higher baseline KL-6 value and more frequent pre-existing IPs were associated with development of DIIP by univariate analysis. At the onset of DIIP, elevated serum KL-6 levels with concomitantly increased ground glass opacity (GGO) in Chest CT were demonstrated. DIIP was improved by only cessation of causative agents in five patients but steroid therapy was needed in one patient. Conclusions DIIP is a plausible complication of anti-IL-17/23 biologics. Age, baseline KL-6 level and underlying IP could be the risk factors for DIIP development. Serum KL-6 levels and chest CT are useful for not only predicting but also detecting DIIP caused by anti-IL-17/23 biologics.