There were three presentations that I thought were very interesting and important. The first study was an update of the ASCEMBL trial in which patients were randomized to either asciminib or bosutinib for multi-resistant CML. And we now have two-year data, which confirms a substantially better outcome for the patients who were randomized to as asciminib, with the number of patients who achieved both major molecular response and an MR 2, which is below 1% BCR-ABL being significantly higher in the asciminib arm...
There were three presentations that I thought were very interesting and important. The first study was an update of the ASCEMBL trial in which patients were randomized to either asciminib or bosutinib for multi-resistant CML. And we now have two-year data, which confirms a substantially better outcome for the patients who were randomized to as asciminib, with the number of patients who achieved both major molecular response and an MR 2, which is below 1% BCR-ABL being significantly higher in the asciminib arm. And that difference has remained at two years. There’s also a lot more patients remaining on asciminib than remaining on bosutinib because of the intolerance issues with bosutinib. So it just confirms what we saw with the one-year data, that there’s an advantage to asciminib in these patients with resistance to several prior TKIs.
The second important study to mention is the Canadian study, looking at a second attempt at treatment-free remission for patients who have failed their first attempt on imatinib. Often these patients are 7, 8, 9 years on imatinib, and then stopped the drug and failed, had a molecular relapse. And the Canadian study put those patients on dasatinib and waited until they achieved an MR 4.5, and then waited a further 12 months and then stopped again. And what they found was that there was a very low rate of success using that approach, around about 10%, suggesting that that particular strategy of using a more potent drug for a relatively short period may not be the best way to go when you’re looking at a second attempt at treatment-free remission.
It’s possible that with a longer duration of MR 4.5, they might have achieved a much better success rate, but we don’t know that until that’s actually addressed in a clinical trial. So it’s an important message there for clinicians that, at the moment at least, the evidence would be that if you want to try a second time, you need to wait a substantial period before re-attempting treatment-free remission. And the relative role of a more potent drug versus just continuing imatinib also needs to be established.
