Osimertinib has become the standard of care for epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer (NSCLC). In order to prevent or treat toxicity, the osimertinib dose may be reduced. However, data regarding the impact of dose reduction during treatment are limited. We aimed to compare the efficacy of osimertinib early dose reduction during the first 3 months of treatment with late dose reduction in EGFR-mutated advanced NSCLC. This retrospective study included patients with EGFR-mutated advanced NSCLC who received osimertinib. We constituted two groups: 'early dose reduction' (early) with patients receiving a reduced dose of osimertinib from 80 to 40 mg within the 3 months of osimertinib initiation and 'late dose reduction' (late) with patients receiving a reduced dose after 3 months of full-dose treatment. Thirty-five patients were included, with 17 and 18 patients in the early and late groups, respectively, and a higher median age in the early group (76 vs. 67 years). The real-world progression-free survival (rwPFS) at 1 year was 70.5% in the early group and 88.9% in the late group (P = 0.31). Median rwPFS was 32.7 and 24.6 months (P = 0.98), and the median overall survival was 46.9 versus not reached in early and late groups, respectively (P = 0.17). Central nervous system rwPFS was not different between the early and late groups: 29.8 and 35.8 months, respectively (P = 0.39). We showed that a reduced dose of osimertinib within the first 3 months of treatment, compared to a later reduced dose, could influence treatment response or patient survival.

中文翻译：

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奥西替尼治疗晚期 EGFR 突变非小细胞肺癌的早期剂量减少。

奥希替尼已成为表皮生长因子受体 (EGFR) 突变的非小细胞肺癌 (NSCLC) 的治疗标准。为了预防或治疗毒性，可以减少奥希替尼的剂量。然而，有关治疗期间减少剂量的影响的数据有限。我们的目的是比较奥希替尼治疗前 3 个月早期剂量减少与晚期剂量减少对 EGFR 突变晚期 NSCLC 的疗效。这项回顾性研究纳入了接受奥希替尼治疗的 EGFR 突变晚期 NSCLC 患者。我们分为两组：“早期剂量减少”（早期）组，患者在开始使用奥希替尼后 3 个月内将奥希替尼剂量从 80 毫克减少至 40 mg；“晚期剂量减少”组（晚期），患者在开始使用奥希替尼 3 个月后接受减少剂量。几个月的全剂量治疗。共纳入 35 名患者，其中早期组和晚期组分别有 17 名和 18 名患者，早期组的中位年龄较高（76 岁与 67 岁）。早期组的真实世界 1 年无进展生存率 (rwPFS) 为 70.5%，晚期组为 88.9%（P = 0.31）。早期组和晚期组的中位 rwPFS 分别为 32.7 个月和 24.6 个月（P = 0.98），中位总生存期分别为 46.9 个月和未达到（P = 0.17）。早期组和晚期组的中枢神经系统 rwPFS 没有差异：分别为 29.8 个月和 35.8 个月（P = 0.39）。我们发现，与后期减少剂量相比，治疗前 3 个月内减少奥希替尼剂量可能会影响治疗反应或患者生存。