What systemic treatment would you offer for metastatic HER2+ breast cancer that has progressed through THP and TDM-1 with predominant CNS progression and without localized treatment options?

For patients after 2 standard lines of HER2-targeted therapies with CNS progression who are not candidates for local CNS therapy, my first option would be to use trastuzumab plus tucatinib (with capecitabine if not previously used) if available (e.g. single patient IND). There is demonstrated activi...