There are studies, MRD directed studies, just to say the most important one was the BLAST
programme that was finished, analysed and published with this bispecific agent, blinatumomab, which
is a bispecific antibody targeting at the same time CD19 positive blast cells, B lineage ALL, and
normal CD3 positive T-cells. The mechanism is that blinatumomab engages these CD3 positive T-
cells against the leukemic blasts and the T-cells kill the leukaemia cells in the end. This agent was
used in monotherapy in a large international study, the BLAST, on MRD positive patients. It was adult
patients and, most interestingly, they expressed high levels of minimal residual disease – from 10 -3
and higher which is an aggravation of the prognostic significance of MRD.

The results were extremely interesting because, with little toxicity and it could be administered as
outpatient, 80% of these patients converted to molecularly negative status which improved their
outcome compared to the historical control group, roughly 25% survival. It was with the BLAST trial
something like 60% complete MRD responders. Many of them were transferred to transplantation,
roughly 70%, that was a successful strategy confirming the ability of blinatumomab to obtain an MRD
negative condition, allowing many more patients to be transplanted and improving the transplant
results. Quite positive information.