National Hospital Organization Hokkaido Cancer Center, Hokkaido, Japan.
National Hospital Organization Osaka National Hospital, Osaka, Japan.
Cancer Med. 2020 Jul;9(14):4929-4940. doi: 10.1002/cam4.3091. Epub 2020 May 18.
Palbociclib is a highly selective, reversible, oral inhibitor of cyclin-dependent kinases 4 and 6 that is approved to treat hormone receptor-positive/human epidermal growth factor receptor 2-negative advanced breast cancer. An open-label, single-arm, Japanese phase 2 study was conducted to investigate the efficacy and safety of palbociclib plus letrozole as first-line treatment in 42 postmenopausal patients with estrogen receptor-positive/human epidermal growth factor receptor 2-negative advanced breast cancer. The probability of progression-free survival originally reported at 1 year was 75.0% (90% confidence interval, 61.3-84.4), but median progression-free survival was not attained at the primary analysis. In this report, updated efficacy and safety results with a longer follow-up period are presented. The median duration of treatment in the updated analysis was 33.0 months (range, 1.8-49.2). The probability of progression-free survival at 1 year was 75.6% (90% confidence interval, 62.4-84.7). Median progression-free survival was 35.7 months (95% confidence interval, 21.7-46.7). Objective response rate and disease control rate were 47.6% (95% confidence interval, 32.0-63.6) and 85.7% (95% confidence interval, 71.5-94.6), respectively. Common treatment-related adverse events (all grades; grade 3/4) were neutropenia (100%; 93%), leukopenia (83%; 60%), and stomatitis (76%; 0%). Treatment-related febrile neutropenia was reported in one patient. In general, no clinically meaningful deterioration in health-related quality of life was observed. Palbociclib plus letrozole remained effective and tolerable in Japanese postmenopausal patients with estrogen receptor-positive, human epidermal growth factor receptor 2-negative advanced breast cancer in this updated analysis.
帕博西尼是一种高度选择性、可逆的细胞周期蛋白依赖性激酶 4 和 6 抑制剂，已被批准用于治疗激素受体阳性/人表皮生长因子受体 2 阴性的晚期乳腺癌。一项开放标签、单臂、日本的 2 期研究旨在调查帕博西尼联合来曲唑作为一线治疗方案在 42 例绝经后激素受体阳性/人表皮生长因子受体 2 阴性的晚期乳腺癌患者中的疗效和安全性。最初报告的 1 年无进展生存率为 75.0%（90%置信区间，61.3-84.4），但主要分析时未达到中位无进展生存期。本报告介绍了随访时间更长的更新疗效和安全性结果。更新分析中治疗的中位持续时间为 33.0 个月（范围，1.8-49.2）。1 年无进展生存率为 75.6%（90%置信区间，62.4-84.7）。中位无进展生存期为 35.7 个月（95%置信区间，21.7-46.7）。客观缓解率和疾病控制率分别为 47.6%（95%置信区间，32.0-63.6）和 85.7%（95%置信区间，71.5-94.6）。常见的治疗相关不良事件（所有级别；3/4 级）为中性粒细胞减少（100%；93%）、白细胞减少（83%；60%）和口腔炎（76%；0%）。1 例患者报告了治疗相关性发热性中性粒细胞减少症。一般来说，未观察到健康相关生活质量的临床意义恶化。在这项更新分析中，帕博西尼联合来曲唑在日本绝经后激素受体阳性、人表皮生长因子受体 2 阴性的晚期乳腺癌患者中仍然有效且耐受良好。
