Overcoming Therapeutic Resistance of Triple Positive Breast Cancer with CDK4/6 Inhibition

Table 2

Ongoing clinical trials combining CDK4/6 inhibitors with HER2-targeted and antihormonal agents in patients with HR+/HER2+ breast cancer.

Clinical trial	Therapeutic agents	Phase	Line of therapy; Disease stage	Location
NCT03054363^a	(i) Palbociclib; (ii) Tucatinib; (iii) Letrozole	Ib/II	line and beyond; Stage IV	United States; ABRCC consortium
NCT02947685; (PATINA)	(i) Palbociclib; (ii) Trastuzumab; (iii) Pertuzumab; (iv) Any AI^b or fulvestrant	III	line maintenance after cycles of induction chemotherapy; Stage IV	United States; Alliance foundation
NCT02907918; (PALTAN)	(i) Palbociclib; (ii) Trastuzumab; (iii) Letrozole	II	Neo-adjuvant therapy; Stage II, III	United States
NCT02675231; (MonarcHER2)	(i) Abemaciclib; (ii) Trastuzumab; (iii) Fulvestrant	II	line and beyond; Stage IV	Worldwide
NCT02448420; (PATRICIA)	(i) Palbociclib; (ii) Trastuzumab; (iii) Letrozole	II	to line of therapy; Stage IV	Spain; SOLTI group
NCT02530424; (NA-PHER2)	(i) Palbociclib; (ii) Trastuzumab; (iii) Pertuzumab; (iv) Fulvestrant	II	Neo-adjuvant therapy; Stage I-III	Italy
NCT03304080	(i) Palbocilib; (ii) Trastuzumab; (iii) Pertuzumab; (iv) Anastrozole	I/II	line; Stage IV	United States

a: clinical trial number in the US National Institutes of Health clinical trial database; b–AI: aromatase inhibitor.