Novartis generics subsidiary Sandoz has started a late-stage trial of its biosimilar version of Amgen and Pfizer’s blockbuster arthritis drug Enbrel (etanercept).
The trial is designed to support registration of biosimilar etanercept in the US and EU but will focus on moderate to severe chronic plaque-type psoriasis, a much smaller indication for Enbrel than rheumatoid arthritis.
Observers have suggested that psoriasis will be an easier and shorter development and regulatory route for Sandoz’ etanercept, allowing the biosimilar to reach the market sooner and potentially allowing clinicians to prescribe it off-label for arthritis ahead of a phase III trial in this setting.
Enbrel has been a huge success for Amgen and Pfizer and continues to grow despite being on the market for two decades. Last year, Amgen reported $4.2bn in sales from the US and Canada, while Pfizer – which licenses rights elsewhere – booked $3.8bn.
These huge sales of the drug despite its long stay on the market are indicative of the issues driving the development of biosimilars around the world.
Commenting on Sandoz’ plans, psoriasis specialist Alan Menter of Baylor University Medical Centre in the US, said: “The continued increase in spending on biological agents for treatment of immune-mediated diseases such as rheumatoid arthritis and psoriasis is a growing concern among physicians in many developed and developing countries.”
“A high-quality and clinically-proven biosimilar version of etanercept could play an important role in generating much-needed savings for healthcare systems,” he added.
The route to market in the US for Sandoz product may prove challenging, however, given that Amgen was awarded a patent extension in 2011 that, unless challenged successfully in the courts, extends exclusivity on the market out to 2028.
Outside the US the situation is very different, with Enbrel copies already on the market in India and China from the likes of Cipla and CP Guojian Pharmaceutical, although these are different in amino acid sequence from Amgen and Pfizer’s drug so could be launched under current US and EU biosimilar guidelines.
Sandoz seems to be leading the field in development of biosimilars for established pharma markets, and is currently claiming more than 50 per cent market share of all biosimilars approved in the US, Canada, Europe, Japan and Australia.
It predicts that the market for biosimilars will rise from around $500m in 2011 to between $2bn and $3bn in 2015 and more than $15bn by 2020.
Sandoz currently has three biosimilars on the market (somatropin, filgrastim and epoetin) and five in late-stage testing, including etanercept, rituximab and peg-filgrastim.