SABCS: Merck's Keytruda notches win in triple-negative breast cancer as Roche's Tecentriq falls short

Tecentriq failed to top chemo in reaching pathologic complete response in triple-negative breast cancer patients. (Pixabay)

SAN ANTONIO—Merck & Co.'s Keytruda and Roche's Tecentriq are battling for immuno-oncology supremacy in an ever-growing range of indications. But in hard-to-treat triple-negative breast cancer (TNBC), Keytruda's latest data came out on top.

Adding Keytruda to standard-of-care chemotherapy ahead of surgery delivered pathologic complete responses—a lack of cancer cells in surgically removed tissue––in 64.8% of newly diagnosed TNBC patients whose disease had spread to the lymph nodes, a new subanalysis shows. Just 44.1% of those treated with chemo alone could say the same.

Drawn from Keytruda's phase 3 Keynote-522 study, the subgroup data were presented Thursday at the San Antonio Breast Cancer Symposium. They back up top-line numbers released in September showing a Keytruda-chemo combo achieved a pathologic complete response in 64.8% of the study's patients compared with 51.2% on chemo alone.

Overall, patients in the Keynote-522 study also showed a 37% risk reduction in disease recurrence after surgery compared with solo chemo, a result that wasn't statistically significant.

RELATED: ESMO: Merck's Keytruda posts first-in-class victory in pre-surgery breast cancer