ASCENT-04 is a study that was presented last year at ASCO 2025 and published in The New England Journal of Medicine which had demonstrated that sacituzumab govitecan, the TROP-2 antibody-drug conjugate, along with the checkpoint inhibitor pembrolizumab, when given in combination had an improved progression free survival as compared to giving standard chemotherapy plus pembrolizumab for patients who have PD-L1 positive frontline advanced triple-negative breast cancer, which is about 40% of the population. So at ASCO 2026 we were presenting data of progression free survival 2, as well as the subsequent therapies that patients received.

Could you outline the methodology?

In ASCENT-04 there were a little shy of 450 patients that were randomly assigned in a 1:1 randomisation to SG, sacituzumab govitecan, plus pembrolizumab compared to chemo plus pembro. The primary endpoint of that study was progression free survival by blinded independent central review. It’s worth noting in the study if patients on the control arm had bigger verified progression they could received SG monotherapy, as provided on the study, which turned out to be about 80% of patients, or they could receive just the standard of care treatment. Then the patients in the SG plus pembro arm would receive local therapy at the time of progression. So we really are, in the presentation, focussing primarily on PFS2, which was an exploratory analysis which was looking at the time from randomisation to the time of progression on next-line therapy or death, whichever one came first.

What did you find?

Ultimately, we saw that with a median follow-up of about 14 months that there was an improvement not only in progression free survival but also with progression free survival 2 where in the patients who were randomly assigned to SG and pembro there was an improvement in PFS2 as compared to standard chemo plus pembro which led to a stratified hazard ratio of 0.67 with a confidence interval that did not cross 1.0. If we look at the median in the SG plus pembro arm it was not yet reached, it was about 21 months in the control arm. So ultimately we saw that there was about a third reduction in the risk of a PFS2 event favouring those that were randomly assigned to SG and pembro.

What impact could these findings have in the clinic?

We had previously reported the safety profiles of giving SG and pembro and there were no new safety profiles beyond what we had already known with SG in other randomised studies. So the data today, when we think about this in totality, are really demonstrating that for those patients who have PD-L1 positive advanced triple-negative breast cancer, frontline, which again is about 40% of those with advanced triple-negative breast cancer, that SG plus pembro is really a standard of care in these patients, given that we’re seeing this clinical improvement across these various outcomes.