Biogen Idec and Genentech are to co-develop a new cancer drug that the latter firm has just acquired the US rights for from Switzerland’s GlycArt.

The compound in question is GA101, a humanised anti-CD20 monoclonal antibody which works in a similar way to Rituxan (rituximab), the non-Hodgkin’s lymphoma and rheumatoid arthritis blockbuster that Genentech and Biogen co-developed and market. The new pact is an extension of the Rituxan collaboration.

Under the terms of the deal, Biogen will make an upfront payment of $31.5 million to its partner and record it as an R&D expense in the fourth quarter. The companies will share operating profits in the USA, while Roche, which is trying to buy the 44% stake in Genentech it does not already own, will retain rights to GA101. Additional financial terms were not disclosed.

Genentech took a charge of $105 million in the third quarter to get hold of the commercialisation rights to GA101 which is in Phase I/II clinical trials for CD20-positive B-cell malignancies such as NHL and chronic lymphocytic leukaemia. GlycArt, which was bought by Roche in 2005 will provide an update on Phase I data for GA101 at the American Society of Hematology meeting in December.