Follow up phase will continue until either 100% of the patients have died, are lost to follow up or have withdrawn consent or a maximum of 4 years from the last patient enrolled, whichever comes first. All other efficacy and safety endpoints will be updated at this time. In the unlikely event that the study will be closed and patients are still responding to treatment at this time, Celgene will discuss with the treating physicians options to provide further treatment to the patient after study closure in line with local regulation.