Further studies are also required to investigate other neratinib based combinations such as neratinib in combination with hormone treatments and/or CDK4/6 inhibitors in HER2-low ER-positive breast cancer cells and PDOs, as well as neratinib in combination with anti-PDL1/PD1 in HER2-low/TNBC cells and PDOs. Here, CDK4 is linked to breast carcinoma.