Table 4.

HER2-targeted therapy.

	Total (n = 24)
HER2 therapy at trial start
Pertuzumab + Trastuzumab	19 (79 %)
Trastuzumab	1 (4 %)
Trastuzumab deruxtecan	1 (4 %)
Trastuzumab Emtansine	3 (12 %)
Change of HER2 therapy
No	19 (79 %)
Yes	5 (21 %)
What was the change in HER2 therapy
Pertuzumab + Trastuzumab to Trastuzumab emtansine prior to 3 month visit	2 (40 %)
Trastuzumab emtansine to Lapatinib prior to 9 month visit  Pertuzumab + Trastuzumab to Trastuzumab emtansine prior to 12 month visit	1 (20 %) 1 (20 %)
Trastuzumab emtansine to Trastuzumab prior to 12 month visit	1 (20 %)