PROBLEM TO BE SOLVED: To provide a combination therapy of an HSP90 inhibitor targeting HSP90 greatly involved in survival of cancer cells and other antitumor agents.SOLUTION: An antitumor agent is obtained by combining a triazole compound (A) represented by general formula (1) with an epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (B).COPYRIGHT: (C)2014,JPO&INPIT【課題】癌細胞の生存に大きく関与するHSP90を標的とするHSP90阻害剤と他の抗腫瘍剤との併用療法の提供。【解決手段】下記一般式(1)で表されるトリアゾール化合物(A)と、上皮増殖因子受容体(EGFR)チロシンキナーゼ阻害剤(B)を組み合わせた抗腫瘍剤。【選択図】図1