The invention relates to a drug combination including: (1) a first drug, which is a CDK inhibitor or pharmaceutically acceptable salt thereof, and (2) a second drug, which is an anti hormone agent or pharmaceutically acceptable salt thereof. The invention also relates to a drug combination including: (1) a first agent, which is a CDK inhibitor or pharmaceutically acceptable salt thereof, (2) a second agent, which is an anti hormone agent or pharmaceutically acceptable salt thereof, and (3) a third agent, which is a reagent regulating PI3K / Akt / mTOR pathway or pharmaceutically acceptable salt thereof.本發明涉及包括以下的藥物組合:(1)第一藥劑,其是CDK抑制劑或其藥學上可接受鹽和(2)第二藥劑,其是抗激素劑或其藥學上可接受鹽。本發明還涉及包括以下的藥物組合:(1)第一藥劑,其是CDK抑制劑或其藥學上可接受鹽,(2)第二藥劑,其是抗激素劑或其藥學上可接受鹽,和(3)第三藥劑,其是調節PI3K/Akt/mTOR通路的試劑或其藥學上可接受鹽。