The appraisal committee (section 5) considered evidence submitted by Janssen and a review of this submission by the evidence review group (ERG). See the committee papers for full details of the evidence. The company proposed that this technology be considered in a fast track appraisal using cost-comparison methodology.
3.1 The company proposed that guselkumab should be considered as an alternative to other biological therapies for psoriasis in adults when non-biological systemic treatment or phototherapy is inadequately effective, not tolerated or contraindicated. The committee understood that the company's proposed decision problem was narrower than guselkumab's marketing authorisation. However, it agreed that the proposed population was consistent with previous NICE recommendations for biologicals for psoriasis, and with their use in clinical practice. The committee noted that the company presented comparisons with NICE-recommended biologicals, and considered that this was consistent with the criteria for a cost-comparison appraisal (the appropriateness of specific comparators is discussed in section 3.7). The committee recalled that previous technology appraisal guidance recommendations specified that treatment should stop if there is an inadequate response after induction. An adequate response is defined as:
a 75% reduction in the Psoriasis Area and Severity Index score (PASI 75) from when treatment started or
a 50% reduction in the PASI score (PASI 50) and a 5‑point reduction in Dermatology Life Quality Index (DLQI) from when treatment started.
The committee considered that it would be reasonable to consider a similar approach for this appraisal. It accepted that the company's positioning reflected the likely place of guselkumab in clinical practice, and concluded that the company's decision problem was relevant to clinical practice.
3.2 Guselkumab has been studied in 3 randomised controlled trials including a total of 2,096 adults with plaque psoriasis. It was directly compared with adalimumab in 2 trials, VOYAGE‑1 and VOYAGE‑2. In these trials, guselkumab was associated with statistically significant improvements compared with adalimumab in primary and secondary outcomes, including PASI response rates. The committee noted, in particular, that patients randomised to guselkumab were statistically significantly more likely to have a PASI 75 response after induction (that is, at week 16) compared with adalimumab (VOYAGE‑1: PASI 75 response rates 91.2% and 73.1% respectively, p<0.001). The committee accepted that the results of the VOYAGE trials showed that guselkumab was more effective than adalimumab.
3.3 The company's network meta-analysis compared guselkumab with adalimumab, etanercept, infliximab, ixekizumab, secukinumab and ustekinumab, using data from 45 trials. It understood that the ERG preferred the analyses based only on comparators specified in the decision problem (termed the 'restricted analyses') because these matched the scope. The committee accepted the ERG's view and concluded that the network meta-analysis provided by the company was suitable for decision-making.
Guselkumab provides greater benefits than TNF‑alpha inhibitors and ustekinumab, and similar benefits to secukinumab and ixekizumab
3.4 The committee noted that the results of the network meta-analysis suggested that guselkumab was statistically significantly more effective, in terms of PASI 75 response, than the TNF‑alpha inhibitors (that is, adalimumab, etanercept and infliximab) and ustekinumab. It considered that guselkumab would provide substantial clinical benefits over adalimumab, etanercept, infliximab and ustekinumab in practice. It also considered that, although guselkumab appeared to be statistically significantly better than secukinumab in terms of PASI 75 response in the network meta-analysis, the difference might not be clinically meaningful. The committee also noted that guselkumab was similarly effective to ixekizumab in this outcome, and that no statistically significant difference was seen. It therefore considered that guselkumab was likely to provide similar benefits to secukinumab and ixekizumab in clinical practice. The committee acknowledged that PASI 75 is a key outcome for informing treatment continuation after induction. However, it also understood that patients are interested in having complete clearance of their psoriasis symptoms so it considered that PASI 100 is also a relevant outcome. The committee appreciated that the company analyses also covered a range of outcomes, and that the results for PASI 100 were broadly consistent with those for PASI 75. The committee noted the safety and tolerability outcomes in the company's network meta-analysis and considered that guselkumab had a similar safety profile to other biologicals, regardless of treatment class. It concluded that guselkumab provides substantially greater clinical benefits compared with adalimumab, etanercept, infliximab and ustekinumab, and is likely to provide similar benefits to secukinumab and ixekizumab.
3.5 The company presented a cost-comparison analysis that modelled the total costs of guselkumab, adalimumab and ustekinumab treatment over 5 years. It took into account stopping treatment after induction (based on PASI 75 response rates, which was consistent with the stopping rules specified in NICE technology appraisal guidance for the comparators), using an assumption that guselkumab and the comparators were similarly effective (that is, it assumed clinical similarity between treatments). The analysis also took into account the long-term stopping of treatment during maintenance therapy. The committee noted the ERG's view that assuming similar effectiveness was inappropriate because of the statistically significant differences between treatments in clinical effectiveness. Therefore, the ERG presented exploratory analyses either using the company's assumption of clinical similarity, or using different treatment continuation rates for each treatment based on PASI 75 response rates from the network meta-analysis (see section 3.4). These exploratory analyses included all biologicals and used a 10‑year time horizon. The committee appreciated that guselkumab is statistically significantly more effective than some other subcutaneous biological treatments (see section 3.4). It was aware that differences in effectiveness led to differences in the number of people stopping treatment after induction, resulting in differences in treatment duration between therapies and hence differences in costs to the NHS. It considered that treatment duration should be taken into account in a cost-comparison analysis when it is directly affected by clinical effectiveness, and that when there is a difference in effectiveness between guselkumab and a comparator, different continuation rates should be used. The committee therefore concluded that the ERG's cost-comparison analysis was preferable for decision-making.
3.6 For comparators in its base case, the company focused on adalimumab and ustekinumab. The committee understood that the company chose these because they are the most frequently used biologicals for psoriasis, and accepted this rationale. However, it recalled the statistically and clinically significant increased benefits for guselkumab compared with adalimumab and ustekinumab (see section 3.2), and that such increased benefits affected the cost comparison (see section 3.5). It noted that, in the ERG's analysis, guselkumab was more expensive than adalimumab and ustekinumab. The committee also noted that, when a technology provides greater benefits than a comparator but at a greater cost, it is not possible to reach a conclusion using cost-comparison methods. It therefore concluded that adalimumab and ustekinumab were not acceptable comparators to focus on in a cost-comparison context. Conversely, the committee recognised that, because guselkumab, ixekizumab and secukinumab are likely to provide similar clinical benefits (see section 3.4), it was possible to reach a recommendation using cost-comparison methods by considering the comparison of guselkumab with secukinumab and ixekizumab. It noted that secukinumab has a rapidly growing market share, and that ixekizumab is expected to be used more frequently over time. The committee concluded that ixekizumab and secukinumab, not adalimumab and ustekinumab, were the relevant comparators for the cost-comparison analysis.
3.7 The committee focused on the cost comparison with ixekizumab and secukinumab using the ERG's exploratory analyses (see section 3.5) and taking into account all confidential patient access schemes. In these analyses, the total costs associated with guselkumab were similar to or lower than those associated with ixekizumab and secukinumab (the exact results cannot be reported here because the discounts are confidential). The committee concluded that the criteria for a positive cost comparison were met because:
guselkumab provided similar overall health benefits to ixekizumab and secukinumab and
the total costs associated with guselkumab were similar to or lower than the total costs associated with ixekizumab and secukinumab.
The committee therefore recommended guselkumab as an option for treating plaque psoriasis in adults. It concluded that the recommendations for guselkumab should be consistent with the company's proposal and the NICE recommendations for ixekizumab and secukinumab, that is:
for people with severe disease (a PASI of 10 or more and a DLQI of more than 10) and
when the disease has not responded to standard systemic therapies or when these treatments are unsuitable
and with consideration given to stopping treatment after induction if the disease does not respond adequately.
3.8 The committee noted, as in previous NICE technology appraisals on psoriasis, potential equality issues:
the PASI might underestimate disease severity in people with darker skin
the DLQI has limited validity in some people, and may miss anxiety and depression.
The committee concluded that, when using the PASI, healthcare professionals should take into account skin colour and how this could affect the PASI score, and make the clinical adjustments they consider appropriate. Also, it concluded that, when using the DLQI, healthcare professionals should take into account any physical, psychological, sensory or learning disabilities, or communication difficulties, that could affect the responses to the DLQI and make any adjustments they consider appropriate.