ASCENT-04 is a randomised phase III study that looked at the combination of sacituzumab plus pembrolizumab and compared it to chemotherapy plus pembrolizumab in patients who have PD-L1 positive metastatic triple-negative breast cancer that have previously been untreated. The idea being that we know that sacituzumab govitecan is a highly effective antibody drug conjugate already approved in metastatic triple-negative disease, but as a second line and later option. There’s a lot of data suggesting that combining antibody drug conjugates with checkpoint inhibition could really enhance efficacy. So this study looked to add pembrolizumab to sacituzumab to see if it would do better than our standard of care chemotherapy and pembrolizumab.

The study did find that sacituzumab and pembrolizumab led to significant improvement in progression free survival going from 7.8 months to 11.2 months, with a hazard ratio of 0.65 and a 3.4 month difference between the two arms. I think this benefit suggests that sacituzumab and pembrolizumab could be hopefully a new potential first line standard of care for our patients.

What are the clinical implications of these findings?

I think the data looking at sacituzumab plus pembrolizumab is really the first time that we’ve had a randomised phase III study demonstrate benefits for a combination of an antibody drug conjugate with a checkpoint inhibitor. Seeing that we’re able to significantly improve progression free survival in a cancer subtype that is very aggressive and often challenging to treat I think is very meaningful for our patients. Hopefully this will become available soon for our patients.