When using T-DXd/pertuzumab regimen in frontline treatment of HER2+ metastatic breast cancer, are you adapting the regimen with induction and then de-escalation to maintenance?

Outside of a clinical trial, I do not routinely define a fixed induction-and-maintenance strategy when starting T-DXd with pertuzumab. Instead, I individualize treatment over time based on response, tolerability, and patient priorities. While many patients achieve deep and durable responses, cumulat...

I have not yet used an induction-maintenance approach with T-DXd/pertuzumab in 1L metastatic HER2+ breast cancer, but I do plan to use this approach, as I anticipate many patients will have difficulties tolerating T-DXd/pertuzumab for such a long course. In patients achieving complete or near-comple...

Typically, I would give at least 4 cycles with T-DXd/P and then consider de-escalation. It would depend on response to prior therapy (ie, long vs short disease-free interval), risk factors for lung damage (smoking status, extent of non-cancer scarring in the lung), severity of metastatic progression...