Despite FDA accelerated approval in April, we still need to learn more about resistance to this antibody drug conjugate, said Aditya Bardia, MBBS, MPH, breast medical oncologist, Massachusetts General Hospital, Harvard Medical School.
The FDA granted accelerated approval to sacituzumab govitecan in April based on results seen in patients with triple-negative breast cancer. However, there is still more to learn about resistance to the antibody drug conjugate and what leads to treatment failure, said Aditya Bardia, MBBS, MPH, breast medical oncologist, Massachusetts General Hospital, Harvard Medical School.
What clinical activity of sacituzumab govitecan led to its FDA accelerated approval status earlier this year?
As a single agent, a response rate of 33% was noted with sacituzumab govitecanin patients who had received at least 2 prior lines of therapy for metastatic triple-negative breast cancer. And in this setting, standard chemotherapy would be associated with a response rate of 5% to 10%. So it was more than double as compared to what you would see with standard chemotherapy. And that's why the FDA granted accelerated approval to this agent.
What causes immuno-oncology treatment failure and how are clinicians alerted to this?
That's an area of ongoing research. We don't really understand the mechanisms governing resistance to sacituzumab govitecan, and that's something that we are interested in understanding so that we can build additional therapies and further improve outcomes of patients with metastatic disease.
In terms of what physicians should look out for, standard signs of disease progression. So if someone is having more pain, more symptoms, there's concern for disease progression, [and] then scans should be obtained. Any therapy that's effective should be continued. But if a therapy has stopped working, you should not waste time by continuing an ineffective therapy.