Amgen, Allergan join Rituxan biosimilar challenge with FDA filing

Amgen and Allergan have filed for approval of their biosimilar version of Roche’s CD20-targeting drug Rituxan with the FDA, vying to become the third copycat version of the blockbuster drug approved in the US.

If approved, Amgen and Allergan’s biosimilar – called ABP 798 – will follow in the footsteps of Teva/Celltrion's Truxima and Pfizer's Ruxience, approved by the FDA in 2018 and earlier in 2019, respectively.

A fourth potential rival developed by Novartis subsidiary Sandoz has been cleared in Europe but won’t be developed for the US market after the FDA requested more information on the drug last year.

Rituxan (rituximab) – known as MabThera in some markets outside the US – is used to treat blood cancers including non-Hodgkin's lymphoma (NHL) and chronic lymphocytic leukaemia (CLL), as well as immunological diseases such as rheumatoid arthritis and various forms of vasculitis.

It is still a biggest-selling brand for Roche, but is starting to be hit hard by competition from biosimilars in territories outside the US.

Sales dipped 3% to just under $5 billion in the first nine months of this year, but in the third quarter fell by 33% as lower-cost rivals gathered momentum in Europe and Japan, despite Roche’s efforts to fend off competition with the launch of a more convenient subcutaneous formulation of the drug.

The US accounted for $3.4 billion of that total so Roche is in for a bumpy ride in the coming months if declines follow the same pattern as elsewhere.

Truxima launched in the US last month at a 10% discount to Roche’s US list price, initially only for Rituxan’s oncology indications as it has agreed with Roche not to launch for RA and vasculitis uses until the second quarter of 2020.

Meanwhile, Pfizer has said it will start to roll out Ruxience in the US in January, following its approval for NHL, CLL and vasculitis indications – granulomatosis with polyangiitis and microscopic polyangiitis.

Amgen and Allergan’s statement on the biosimilar filing references those four indications, but not rheumatoid arthritis.