Tecentriq gets its narrow breast cancer label

US approval of Roche’s Tecentriq plus Abraxane in triple-negative breast cancer marks a first for an anti-PD-(L)1 drug, but also leaves an opportunity for Merck & Co’s Keytruda. This is because Tecentriq has been restricted to patients with at least 1% PD-L1 expression, based on interim results of the Impassion-130 trial showing these subjects to be driving the survival benefit (Esmo 2018 – Roche misses the bullseye in triple-negative breast cancer, October 20, 2018). Attention now turns to Keynote-119, a Keytruda study due to read out next month. However, it might be a tall order to expect this to show a benefit in PD-L1 non-expressers as it tests Keytruda as monotherapy; a better bet for Merck might be the Keynote-355 chemo combo trial due to yield data around the year end. And there are other Roche studies reading out that could bolster the Swiss group’s position, as well as acting to confirm Friday’s accelerated approval, which was backed by Impassion-130’s progression-free survival data. Tecentriq’s breast cancer label is in theory conditional on it showing an overall survival benefit, though in practice the chances of an accelerated approval being revoked are slim.