Stefanie Hölsken,1,* Carina Benthin,2,3,* Frederik Krefting,4 Senta Mühlhaus,1 Yvonne Nestoriuc,2,3 Manfred Schedlowski,1,5 Wiebke Sondermann4 1Institute of Medical Psychology and Behavioral Immunobiology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany; 2Clinical Psychology, Helmut-Schmidt-University/University of the Federal Armed Forces Hamburg, Hamburg, Germany; 3Systems Neuroscience, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; 4Department of Dermatology, Venereology and Allergology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany; 5Department of Clinical Neuroscience, Osher Center for Integrative Medicine, Karolinska Institutet, Stockholm, Sweden*These authors contributed equally to this workCorrespondence: Wiebke Sondermann, Department of Dermatology, Venereology and Allergology, University Hospital Essen, University Duisburg-Essen, Hufelandstr. 55, Essen, 45122, Germany, Tel +49201-723-3647, Fax +49201-723-5409, Email wiebke.sondermann@uk-essen.dePurpose: Psoriasis is a highly debilitating chronic inflammatory disease. Increased understanding of its pathophysiology has enabled development of targeted treatments such as biologics. Several medical treatments have been shown to be influenced by patients’ experiences and expectations. However, only little is known about patients’ experiences with and expectations towards biologics. Our objectives were to identify patients’ treatment experiences and treatment expectations and assess their trajectories over the course of treatment with the IL-17A inhibitor secukinumab. Moreover, we aimed to document effects of psoriasis, factors that influence symptomatology, and prior treatment experiences.Patients and Methods: We conducted semi-structured interviews with n = 24 patients with moderate-to-severe plaque psoriasis and employed a qualitative content analysis to derive thematic and evaluative codes. Findings were validated via peer debriefings with experienced dermatologists.Results: Patients reported burdensome physical and psychological psoriasis symptoms and identified factors that can improve or worsen symptomatology, including stress and self-efficacy. Prior treatment experiences were mostly negative. Past barriers to effective treatment included time constraints or limited access. Concerning secukinumab, patients initially expected complete to partial remission of symptoms and occurrence or absence of side effects. Closer inspection of expectations and experiences revealed three trajectories. For most patients, initial expectations were met and future expectations remained unchanged. For the other patients, however, the experience did not match their initial expectation. One group then adapted their future expectations according to their experience, while the other group did not.Conclusion: To our knowledge, this is the first qualitative study to assess expectations towards treatment effectiveness and side effects, their trajectories, and interplay with experiences among psoriasis patients. Our findings highlight the value of further research on the subject in order to optimize care for psoriasis patients and to learn more about the trajectories and influence of treatment expectations in general.Plain Language Summary: Patients’ expectations towards a certain treatment can influence how well it will work and whether side effects occur or not. Such effects have been shown for a wide range of conditions, including dermatological ones. For patients suffering from psoriasis, a chronic inflammatory skin disease, modern biologics offer promising treatment options. Therefore, modern biologics are likely associated with high expectations by patients. Yet, the roles of treatment expectations and the experiences of patients undergoing biologic treatment have only received little attention to date.With this qualitative study, we aimed to understand patients’ perspectives on these treatments, the symptoms they suffer from, expectations towards treatment effectiveness and side effects as well as treatment experiences in the past and over the course of treatment with a modern biologic. To this end, we conducted and transcribed interviews with 24 patients after several months of biologic treatment. We then analyzed interview transcripts to determine underlying categories and summarized these in a common framework.We found that patients’ debilitating physical and psychological symptoms were often not well controlled in past treatments. Still, patients had positive expectations with regard to biologic treatment. For a large group of patients, their actual experiences met their expectations, leaving them with unchanged expectations for the future. Another important finding was the good understanding of factors influencing their symptomatology that patients had, like stress and self-efficacy. The reported findings may aid doctors in their clinical work, to further improve care for psoriasis patients. Keywords: psychodermatology, patient perspective, treatment success, doctor-patient relationship, secukinumab