Endocrine Therapy Assessment and Adherence Risk Factors in Advanced HR+/HER2−Breast Cancer: An Integrated Drug Evaluation and Cox Regression Study

Background This study conducted a comprehensive clinical evaluation of endocrine therapy in patients with advanced hormone receptor (HR)–positive, human epidermal growth factor receptor 2 (HER2)–negative breast cancer and analyzed risk factors affecting medication adherence. Methods Referring to the Guidelines for Comprehensive Clinical Drug Evaluation , a retrospective analysis was performed to assess the safety, efficacy, cost‐effectiveness, innovation, suitability, and accessibility of endocrine therapy in patients with advanced HR‐positive/HER2‐negative breast cancer. Additionally, outpatient and telephone follow‐ups were investigated by calculating medication adherence rates. To evaluate medication adherence, patients with an adherence rate < 80% were classified into the poor adherence group, while those with a rate ≥ 80% were assigned to the good adherence group. Clinical data were compared between the two groups, and Cox regression analysis was used to identify risk factors influencing medication adherence in these patients. Results There were no significant differences in pre‐treatment estradiol (E2) and follicle‐stimulating hormone (FSH) levels among the four groups ( p > 0.05). However, post‐treatment E2 and FSH levels in the Abemaciclib group were significantly lower than those in the Dalpiciclib, Goserelin Acetate, and Everolimus groups ( p < 0.05). The incidence of gastrointestinal reactions and leukopenia in the Dalpiciclib group was significantly higher than in the Abemaciclib, Goserelin Acetate, and Everolimus groups ( p < 0.05). In terms of technological innovation, clinical demand, drug recommendation, and mechanism innovation, the Dalpiciclib group demonstrated significantly greater innovation compared to the Abemaciclib, Goserelin Acetate, and Everolimus groups ( p < 0.05). No significant differences were observed among the Abemaciclib, Dalpiciclib, Goserelin Acetate, and Everolimus groups regarding package insert information, labeling, expiration date, storage conditions, usage suitability, or total scores ( p > 0.05). The Abemaciclib group had lower per‐course and total costs compared to the Dalpiciclib, Goserelin Acetate, and Everolimus groups, with better affordability and availability ( p < 0.05), though no significant differences were found in per‐course costs or drug shortage rates among the groups ( p > 0.05). Beyond the comprehensive clinical drug evaluation, patient medication adherence was also a critical factor affecting treatment outcomes. Among 315 patients assessed for adherence, 61 (19.37%) scored < 6, indicating poor adherence. Univariate and multivariate Cox regression analyses identified low monthly household income, treatment with dalpiciclib succinate tablets, and adverse drug reactions as significant risk factors for poor adherence ( p < 0.05). Conclusion Based on a single‐center comprehensive clinical drug evaluation, abemaciclib exhibits superior performance in reducing sex hormone levels and enhancing cost‐effectiveness. Additionally, a comparatively higher rate of medication adherence was observed among patients within this study. In contrast, dalpiciclib succinate shows distinct advantages in terms of innovation. These findings facilitate the subsequent development of individualized medication guidelines and follow‐up protocols tailored to real‐world clinical practice. Nevertheless, the ultimate efficacy of these specific interventions warrants further validation through large‐scale, prospective investigations.