No over the past few years, more adults have started to be treated by BMT but the numbers are still low.  One recent major advance has been the development of what is known as ‘reduced-intensity conditioning’; this is a milder form of chemotherapy used to prepare the patient for the donor’s bone marrow. This has been used successfully in BMT for some adults with PID. It is likely that more adults with PID will be treated by BMT in the next few years.