本研究是一项单臂、单中心II期临床试验。主要入排标准为:组织学确认的HER2阳性晚期乳腺癌HER2阳性晚期乳腺癌;既往晚期阶段接受过不超过1个系统治疗方案;至少有一个符合RECIST1.1标准的可测量病灶;患者既往可接受过曲妥珠单抗治疗;排除有临床症状的脑转移患者。入组受试者接受达尔西利(125mg/d口服21天、间隔7天)联合吡咯替尼(400mg/d连续口服)治疗,每28天为一个周期,治疗直至疾病进展、不可接受的毒性、死亡、撤回知情同意或研究判断需结束治疗的其他情况。研究主要终点为ORR,次要终点为PFS、总体生存(OS)和安全性。 共计41例患者入组研究并接受了至少一次研究治疗,1例患者因不符合入
受试者的mPFS为11.0个月,12个月PFS率为44.7%。OS数据尚未成熟,预估的12个月和18个月OS率分别为90.0%和82.5%。研究整体安全性可控,无新的安全性信号。
非预设的事后亚组分析显示,HR阴性(81.8% vs 55.6%)和曲妥珠单抗敏感(80.0% vs 53.3%)的受试者ORR有更高的趋势,其PFS也趋于更长(分别为19.3 vs 9.1个月,和12.9 vs 9.1个月)。在13例基线具有无症状脑转移的患者中,整体ORR为84.6%,mPFS为11.0个月。 1.Min Y, et al. Dalpiciclib and pyrotinib in women with HER2-positive advanced breast cancer: a single-arm phase II trial. Nat Commun 14, 6272 (2023). 2.Spring LM, et al. Cyclin-dependent kinase 4 and 6 inhibitors for hormone receptor-positive breast cancer: past, present, and future. Lancet 395, 817-827 (2020).
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