Budget Impact Analysis Shows a Need for Deep Discounts for Biosimilar Infliximab

Although the use biosimilar infliximab in rheumatoid diseases and inflammatory bowel disease has the potential to reduce the treatment costs, a variety of factors may influence the adoption of biosimilar treatments and their potential impacts on healthcare budgets. A recently published budget impact analysis funded by Hospira evaluated the impact of adopting biosimilar infliximab for the treatment of rheumatoid arthritis (RA), ankylosing spondylitis (AS), Crohn’s disease (CD), and ulcerative colitis (UC) in the United Kingdom (UK), Germany, France, Spain, and Italy (the EU5) in the context of other other available biologics, including reference infliximab and other innovator biologics.

The researchers updated an existing budget impact model to include all currently available biological drugs in the EU5 for the treatment of RA, AS, CD, and UC. The model was informed by epidemiological parameters derived from published literature reviewed in July 2015, and market shares of biologics were derived from data provided by Therapy Watch for the years 2012 and 2013. Three types of costs were included in the analysis: annual acquisition costs, administration costs, and therapy monitoring costs. In the base case analysis, existing patients were assumed to remain on an existing biologic treatment or switch to a biosimilar, while naïve patients could be allocated to any available biologic, including biosimilar infliximab. Price discounts for biosimilar infliximab compared with the reference were based on national list prices: 10% (UK), 14% (Germany), 0% (France), 18% (Spain), and 25% (Italy). The time horizon of the model was 5 years, from 2015 to 2020.

A total of 35 leading rheumatologists and gastroenterologists from the EU5 participated in the first round of a 2015 Delphi survey. Of that group, 17 agreed to participate in a second round of the survey. The panel was asked to forecast the uptake of biosimilar infliximab and estimate the proportion of patients eligible for a particular type of biological treatment. The survey respondents indicated that they believed the efficacy and safety of biosimilar infliximab was comparable with that of the reference in rheumatology and gastroenterology indications. Scenarios considered by the panel were the following:

• A biosimilar infliximab available at a 50% discount to the reference
• A biosimilar infliximab available at a 75% discount to the reference
• Availability of clinical and observational study evidence confirming efficacy and safety of biosimilar infliximab in extrapolated indications (CD and UC)
• Availability of vedolizumab for the treatment of CD and UC
• Availability of a biosimilar etanercept for the treatment of RA and AS
• Availability of a rituximab biosimilar for the treatment of RA

Based on this model, the researchers projected that, by the year 2020, the percentage of total patients receiving biosimilar infliximab for rheumatology and gastroenterology indications, respectively, in the EU5 would be as follows:

• UK: 1.8%, 12.7%
• Germany: 1.9%, 18.4%
• France: 2.3%, 4.0%
• Spain: 1.8%, 13.1%
• Italy: 2.2%, 32.9%

The researchers found that, for all indications studied, the total market share of biosimilar infliximab was driven primarily by an increasing share of naïve patients who would be prescribed the biosimilar over time. The percentage of naïve patients in the EU5 who would receive biosimilar infliximab for rheumatology and gastroenterology indications, respectively, by 2020 were as follows:

• UK: 16.3%, 56.3%
• Germany: 16.3%, 35.0%
• France: 16.3%, 20.0%
• Spain: 16.3%, 67.5%
• Italy: 16.3%, 70.0%

In the base case analysis, in all EU5 countries except France—where budget was largely unaffected for RA—spending on the rheumatology indications studied was reduced following biosimilar adoption. In the remaining nations, savings were obtained from biosimilar adoption for RA at year 5 (2020). Spending for AS increased in the UK and France, though savings were observed in Germany, Spain, and Italy.

Base case analysis for gastroenterology indications revealed that biosimilar infliximab adoption decreased budgets only for Spain and Italy. Budgets increased over the 5-year horizon for the UK, Germany, and France (the researchers note that presumed availability of vedulizumab in the UK and Germany had a large effect on total budget).

However, the analysis demonstrated that specific factors could influence the budget impact of the biosimilar’s adoption:

• If the price of biosimilar infliximab was set at a 50% discount to the reference, biosimilar adoption decreased budgets in all EU5 nations. In rheumatology, the savings produced in 2020 ranged from €22 million in France to €81 million in Italy. In gastroenterology, budget savings ranged from €12 million in Italy to approximately €250 million in the UK.
• If the biosimilar’s price was set at a 75% discount to the reference infliximab, savings in rheumatology ranged from €66 million in France to €289 million in Germany. In gastroenterology, savings ranged from €24 million in Italy to €340 million in the UK.

The researchers concluded that the introduction of biosimilar infliximab would lead to increasing budgets in some countries, and would only lead to modest savings in other countries. Because savings were produced only when discounts reached 50% or more, the authors state that policy makers should ensure substantial price reductions in order to spur physician uptake of biosimilars and generate cost savings in healthcare budgets.