Assessment of Vitamin D Metabolism in Patients with Cushing's Disease in Response to 150,000 IU Cholecalciferol Treatment.

In this study we aimed to assess vitamin D metabolism in patients with Cushing's disease (CD) compared to healthy individuals in the setting of bolus cholecalciferol treatment. The study group included 30 adults with active CD and the control group included 30 apparently healthy adults with similar age, sex and BMI. All participants received a single dose (150,000 IU) of cholecalciferol aqueous solution orally. Laboratory assessments including serum vitamin D metabolites (25(OH)D3, 25(OH)D2, 1,25(OH)2D3, 3-epi-25(OH)D3 and 24,25(OH)2D3), free 25(OH)D, vitamin D-binding protein (DBP) and parathyroid hormone (PTH) as well as serum and urine biochemical parameters were performed before the intake and on Days 1, 3 and 7 after the administration. All data were analyzed with non-parametric statistics. Patients with CD had similar to healthy controls 25(OH)D3 levels (p > 0.05) and higher 25(OH)D3/24,25(OH)2D3 ratios (p < 0.05) throughout the study. They also had lower baseline free 25(OH)D levels (p < 0.05) despite similar DBP levels (p > 0.05) and lower albumin levels (p < 0.05); 24-h urinary free cortisol showed significant correlation with baseline 25(OH)D3/24,25(OH)2D3 ratio (r = 0.36, p < 0.05). The increase in 25(OH)D3 after cholecalciferol intake was similar in obese and non-obese states and lacked correlation with BMI (p > 0.05) among patients with CD, as opposed to the control group. Overall, patients with CD have a consistently higher 25(OH)D3/24,25(OH)2D3 ratio, which is indicative of a decrease in 24-hydroxylase activity. This altered activity of the principal vitamin D catabolism might influence the effectiveness of cholecalciferol treatment. The observed difference in baseline free 25(OH)D levels is not entirely clear and requires further study.

Biosimilar Infliximab in Inflammatory Bowel Disease: Outcomes of a Managed Switching Programme.

BACKGROUND AND AIMS: Biosimilar infliximab CT-P13 offers the potential for large drug acquisition cost savings. However, there are limited published data regarding its efficacy, safety, and immunogenicity in inflammatory bowel disease [IBD], particularly in switching IBD patients from originator to biosimilar infliximab. We present the outcomes of a service evaluation of switching IBD patients established on originator infliximab to biosimilar, using a managed switching programme funded via a gain share agreement in a UK teaching hospital. METHODS: Evaluation outcomes included drug persistence, changes in drug acquisition costs, patient-reported side effects, adverse events, patient outcomes assessed using the IBD-control Patient-Reported Outcome Measures [PROM] questionnaire, serum drug and antibody levels, and routinely collected biochemical markers. RESULTS: A total of 143 patients with IBD [118 Crohn's disease, 23 ulcerative colitis, 2 IBD unclassified] were switched from originator infliximab to CT-P13. Patients reported a similar incidence of side effects before and after switch. No clinically significant differences were observed in mean C-reactive protein [CRP], albumin, haemoglobin levels, or platelet and white cell counts after the switch to CT-P13, whereas mean IBD-control-8 score improved from 10.4 to 11.2 [p = 0.041]. There was no significant difference in drug persistence between biosimilar and originator infliximab [p = 0.94] and no increase in immunogenicity was found. Drug acquisition costs decreased by £40,000-60,000 per month. CONCLUSIONS: A managed switching programme from originator infliximab to biosimilar CT-P13 in IBD, using a gain-share agreement, delivers significant cost savings and investment in clinical services while maintaining similar patient-reported outcomes, biochemical response, drug persistence, and adverse event profile.