A systematic review and economic evaluation of adalimumab and dexamethasone for treating non-infectious intermediate uveitis, posterior uveitis or panuveitis in adults

BACKGROUND

Non-infectious intermediate uveitis, posterior uveitis and panuveitis are a heterogeneous group of inflammatory eye disorders. Management includes local and systemic corticosteroids, immunosuppressants and biological drugs.

OBJECTIVES

To evaluate the clinical effectiveness and cost-effectiveness of subcutaneous adalimumab (Humira^®; AbbVie Ltd, Maidenhead, UK) and a dexamethasone intravitreal implant (Ozurdex^®; Allergan Ltd, Marlow, UK) in adults with non-infectious intermediate uveitis, posterior uveitis or panuveitis.

DATA SOURCES

Electronic databases and clinical trials registries including MEDLINE, EMBASE, Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects and the World Health Organization's International Clinical Trials Registry Platform were searched to June 2016, with an update search carried out in October 2016.

REVIEW METHODS

Review methods followed published guidelines. A Markov model was developed to assess the cost-effectiveness of dexamethasone and adalimumab, each compared with current practice, from a NHS and Personal Social Services (PSS) perspective over a lifetime horizon, parameterised with published evidence. Costs and benefits were discounted at 3.5%. Substantial sensitivity analyses were undertaken.

RESULTS

Of the 134 full-text articles screened, three studies (four articles) were included in the clinical effectiveness review. Two randomised controlled trials (RCTs) [VISUAL I (active uveitis) and VISUAL II (inactive uveitis)] compared adalimumab with placebo, with limited standard care also provided in both arms. Time to treatment failure (reduced visual acuity, intraocular inflammation, new vascular lesions) was longer in the adalimumab group than in the placebo group, with a hazard ratio of 0.50 [95% confidence interval (CI) 0.36 to 0.70; p < 0.001] in the VISUAL I trial and 0.57 (95% CI 0.39 to 0.84; p = 0.004) in the VISUAL II trial. The adalimumab group showed a significantly greater improvement than the placebo group in the 25-item Visual Function Questionnaire (VFQ-25) composite score in the VISUAL I trial (mean difference 4.20; p = 0.010) but not the VISUAL II trial (mean difference 2.12; p = 0.16). Some systemic adverse effects occurred more frequently with adalimumab than with placebo. One RCT [HURON (active uveitis)] compared a single 0.7-mg dexamethasone implant against a sham procedure, with limited standard care also provided in both arms. Dexamethasone provided significant benefits over the sham procedure at 8 and 26 weeks in the percentage of patients with a vitreous haze score of zero (p < 0.014), the mean best corrected visual acuity improvement (p ≤ 0.002) and the percentage of patients with a ≥ 5-point improvement in VFQ-25 score (p < 0.05). Raised intraocular pressure and cataracts occurred more frequently with dexamethasone than with the sham procedure. The incremental cost-effectiveness ratio (ICER) for one dexamethasone implant in one eye for a combination of patients with unilateral and bilateral uveitis compared with limited current practice, as per the HURON trial, was estimated to be £19,509 per quality-adjusted life-year (QALY) gained. The ICER of adalimumab for patients with mainly bilateral uveitis compared with limited current practice, as per the VISUAL trials, was estimated to be £94,523 and £317,547 per QALY gained in active and inactive uveitis respectively. Sensitivity analyses suggested that the rate of blindness has the biggest impact on the model results. The interventions may be more cost-effective in populations in which there is a greater risk of blindness.

LIMITATIONS

The clinical trials did not fully reflect clinical practice. Thirteen additional studies of clinically relevant comparator treatments were identified; however, network meta-analysis was not feasible. The model results are highly uncertain because of the limited evidence base.

CONCLUSIONS

Two RCTs of systemic adalimumab and one RCT of a unilateral, single dexamethasone implant showed significant benefits over placebo or a sham procedure. The ICERs for adalimumab were estimated to be above generally accepted thresholds for cost-effectiveness. The cost-effectiveness of dexamethasone was estimated to fall below standard thresholds. However, there is substantial uncertainty around the model assumptions. In future work, primary research should compare dexamethasone and adalimumab with current treatments over the long term and in important subgroups and consider how short-term improvements relate to long-term effects on vision.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42016041799.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.