The Clinical and Cost Effectiveness of Ustekinumab for the Treatment of Psoriatic Arthritis:A Critique of the Evidence

The National Institute for Health and Care Excellence (NICE) invited the manufacturer of ustekinumab (Janssen) to submit evidence for the clinical and cost effectiveness of ustekinumab for the treatment of active psoriatic arthritis (PsA) as part of the Institute's single technology appraisal (STA) process. The Centre for Reviews and Dissemination and the Centre for Health Economics Technology Appraisal Group at the University of York were commissioned to act as the independent Evidence Review Group (ERG). This article provides a description of the ERG review of the manufacturer's evidence submission, and summarises the NICE Appraisal Committee's final guidance (TA340) issued in June 2015. The manufacturer presented evidence on ustekinumab for two patient populations: (1) a tumour necrosis factor-α (TNFα)-inhibitor-naïve population who had not previously received any TNFα inhibitors (biologics); and (2) a TNFα-inhibitor-exposed population who had previously received at least one TNFα inhibitor. The clinical evidence for ustekinumab was derived from two randomised controlled trials (PSUMMIT 1 and 2), in which a total of 927 patients who had not responded to previous disease-modifying antirheumatic drug therapies received ustekinumab 45 mg, ustekinumab 90 mg, or placebo. These data suggested that ustekinumab is more effective than placebo over 16-24 weeks in terms of both joint and skin response. In the absence of head-to-head comparisons between different biologics (ustekinumab, golimumab, etanercept, adalimumab and infliximab), the manufacturer conducted a network meta-analysis to estimate the relative efficacy of treatments for the TNFα-inhibitor-naïve population. Results of this analysis were marked as academic in confidence and are therefore not reported. For the TNFα-inhibitor-exposed population, the clinical analysis was limited to ustekinumab versus conventional management only, and was based on a subgroup of 180 patients from the PSUMMIT 2 trial. The ERG raised concerns relating to the lack of data on the long-term efficacy of ustekinumab, the limited data available for the exposed population, and the lack of consideration of the sequential use of treatments. Based on the manufacturer's original model, the ERG found ustekinumab to be dominated by golimumab in the anti-TNF-inhibitor-naïve population, and had an incremental cost-effectiveness ratio (ICER) of £29,843/quality-adjusted life-years versus conventional management in the exposed population. The ERG's analyses highlighted the fact that there is significant uncertainty around the model results. In addition, the ERG's exploratory cost-effectiveness analysis, which incorporated the sequential use of TNFα inhibitors, suggested that ustekinumab would not be cost effective if it were used as second-line treatment. The initial NICE recommendations asserted that ustekinumab was not recommended for treating active PsA. However, the manufacturer submitted a post-consultation model that included a Patient Access Scheme (PAS), halving the unit cost of ustekinumab 90 mg to £2147 (the same as a 45 mg dose). The NICE final recommendations were that, dependent on the inclusion of the PAS, ustekinumab is recommended as an option, along or in combination with methotrexate, for treating active PsA in adults only when treatment with TNFα inhibitors is contraindicated but would otherwise be considered, or the person has previously had treatment with one or more TNFα inhibitors, which has failed.