Janssen-Cilag, a subsidiary of US healthcare giant Johnson & Johnson, has been granted conditional approval in Europe for Darzalex (daratumumab) to treat patients with relapsed and refractory multiple myeloma (MM). The accelerated approval is indicated for patients whose prior therapy for the blood cancer included a proteasome inhibitor and an immunomodulatory agent, and whose disease has since progressed.

Daratumumab is the first CD38-directed monoclonal antibody approved in Europe. The drug works by binding to CD38 – a signalling molecule – and triggering the patient’s immune system to attack the cancer cells.

Approval was based on data from a Phase 2 study as well as three additional supportive studies which demonstrated that 83% of patients achieved stable disease or better. Patients who relapse after treatment with standard therapies have poor prognoses and few treatment options. MM is the second most common form of blood cancer and nearly 29% of patients die within one year of diagnosis.

Jane Griffiths, chairman of Janssen Europe, Middle East and Africa, said the company would continue to study the drug’s potential across the treatment system for both MM and other types of tumors.

Additional studies are ongoing or planned to assess daratumumab’s potential in other cancerous and pre-cancerous diseases where the CD38 molecule is expressed. Janssen licensed daratumumab from Danish biotechnology company Genmab in August 2012.