Would you feel comfortable changing to subcutaneous pertuzumab/trastuzumab in a patient who has already been receiving IV formulation?

Yes, I have been switching people over from IV therapy to SQ over the past few months, and patients have liked it.

Conversely, most patients who start SQ HP don't want to switch to IV therapy.

Yes, I am comfortable making the switch to subcutaneous formulation, based on the results of the FeDeriCa study. The key points of the study are:

1. The fixed-dose combination of pertuzumab and trastuzumab for subcutaneous injection provides non-inferior serum concentrations of pertuzumab to intrav...

Yes, I see no reason to avoid a change during therapy.