Abstract

Background: Two new drugs provide startling benefits in the treatment of age related macular degeneration (AMD). The widespread use of bevacizumab (avastin) as a low cost off-label alternative to ranibizumab (Lucentis) prompts questions as how much better the latter would have to be to justify its 50 fold higher price.

Aims: To compare the clinical and cost effectiveness of ranibizumab compared to bevacizumab using available published data supplemented by assumptions on relative efficacy and side effects.

Methods: A cost effectiveness model was developed to assess the cost per Quality Adjusted Life Year (QALY) over ten years, with allowance for mortality in this elderly patient group. Efficacy data for ranibizumab were based on licensing trials. The effects of varying the relative efficacy of bevacizumab in terms of visual acuity were explored along with different assumptions on side effects and prices.

Results: For predominantly classic AMD, as the efficacy of bevacizumab relative to ranibizumab would have to be around 40% for the latter to achieve £30k per QALY, a NICE threshold. A doubling of the side effect profile for bevacizumab made minimal difference to these results. These results were based on based on current US prices. If the price of ranibizumab was reduced by three quarters, it would have to be more than 5% more effective to achieve the NICE threshold. Similar but worse results applied to the other main form of AMD, minimally occult or occult with no classic lesions (MC/OC).

Discussion: For ranibizumab to achieve an acceptable cost effectiveness relative to bevacizumab it would have to score 2.5 times better in terms of visual acuity. This seems highly unlikely given the similarity of the molecules and the limited data available. The results are not sensitive to side effects. The price of ranibizumab would have to be drastically reduced for it to be cost effective.

Conclusion: Ranibizumab is highly unlikely to be a cost effective alternative to bevacizumab. Data are required comparing the two drugs directly. NICE is appraising ranibizumab but cannot compare it with bevacizumab due to it being unlicensed. A strong case exists for the Department of Health referring bevacizumab to NICE.