Janssen-Cilag’s Imbruvica has become the first therapy to be specifically approved for the rare blood cancer Waldenstrom's macroglobulinemia in Europe.

A type of non-Hodgkin lymphoma, WM usually gets worse slowly over time and causes abnormal blood cells to grow within the bone marrow, lymph nodes, liver and spleen. Abnormal B-cells also overproduce proteins that can cause excess bleeding and problems with vision and the nervous system.

European approval of Imbruvica (ibrutinib) for the condition was based on data from a Phase II multicenter study showing that 91% of patients experienced some degree of tumour shrinkage after taking the drug.

Also, estimated progression-free survival and overall survival rates at 24 months were 69% and 95%, respectively, and, on the safety side, the most commonly occurring adverse reactions in WM patients treated with Imbruvica were neutropenia, thrombocytopenia, diarrhoea, rash, nausea, muscle spasms, and fatigue.

The drug is already on the market in Europe to treat adult patients with relapsed or refractory mantle cell lymphoma and certain adult patients with chronic lymphocytic leukaemia.

Earlier this year, Imbruvica picked up its fourth approval, for WM, in the US, where it is jointly developed and commercialised by Pharmacyclics - now part of AbbVie - and Janssen Biotech. In Europe and rest of the world Janssen-Cilag holds marketing rights.