van Rhee, FritsRothman, MargaretHo, Kai FaiFleming, SarahWong, Raymond S.Fosså, AlexanderDispenzieri, AngelaCavet, JamesMunshi, NikhilVermeulen, JessicaCasper, Corey2015-05-042015van Rhee, F., M. Rothman, K. F. Ho, S. Fleming, R. S. Wong, A. Fosså, A. Dispenzieri, et al. 2015. “Patient-reported Outcomes for Multicentric Castleman’s Disease in a Randomized, Placebo-controlled Study of Siltuximab.” The Patient 8 (2): 207-216. doi:10.1007/s40271-015-0120-5. http://dx.doi.org/10.1007/s40271-015-0120-5.1178-1653http://nrs.harvard.edu/urn-3:HUL.InstRepos:15034989Background: Multicentric Castleman’s disease (MCD) is a rare lymphoproliferative disorder driven by dysregulated interleukin-6 production. MCD has a poor prognosis, and treatment is generally noncurative and aimed at symptom relief. Siltuximab is a novel, monoclonal interleukin-6 antibody recently shown to be effective in a registration clinical trial. MCD symptoms, such as fatigue, pain, and weakness, are most appropriately quantified using patient-reported outcome (PRO) measures. We assessed the effect of siltuximab on patient perception of symptoms, functional status, and wellbeing using PRO instruments. Methods: We analyzed results of a randomized, double-blind trial comparing siltuximab 11 mg/kg every 3 weeks with placebo to treat MCD. Subjects (N = 79) completed the recently developed MCD–Symptom Scale (MCD–SS), the Functional Assessment of Chronic Illness Therapy–Fatigue (FACIT–Fatigue) scale, and the Short Form (SF)-36 at predetermined time points throughout the treatment period. Scores were compared at baseline and over time between the treatment arms and PRO instruments. Results: At baseline, the mean number of symptoms reported was 9.2 (standard deviation 3.76) out of 16 total, as measured by the MCD–SS. Fatigue was a key symptom across all PRO instruments. Siltuximab-treated subjects reported early improvements in symptoms compared with subjects in the placebo arm on both the MCD–SS and FACIT–Fatigue scale. Statistically significant improvements in five SF-36 domains were observed in siltuximab-treated patients, namely role physical, role emotional, vitality, bodily pain, and mental health. Conclusions: Patients with MCD commonly report impairments in functioning, wellbeing, and fatigue at baseline. Siltuximab-treated patients reported significant improvements in these outcomes after treatment. Electronic supplementary material The online version of this article (doi:10.1007/s40271-015-0120-5) contains supplementary material, which is available to authorized users.en-USJournal Article2015-05-0410.1007/s40271-015-0120-5