RESUMO
Background: Tucidinostat, which is a subtype-selective histone deacetylase inhibitor, has been approved in China for the treatment of hormone receptor-positive (HR+) human epidermal growth factor receptor 2-negative (HER2-) advanced breast cancer (ABC). However, existing evidence mainly stemmed from randomized controlled trials, and might have limitations in representing the complexities of clinical practice and diverse patient populations. Therefore, there is a need to explore the efficacy and optimal therapeutic modality for tucidinostat in real-world clinical settings. Methods: The objective of this real-world study was to analyze the clinical data of 47 patients with HR+/HER2- ABC who received tucidinostat treatment at West China Hospital, Sichuan University, between August 2020 and May 2023. The primary outcomes were progression-free survival (PFS) and clinical benefit rate [CBR; defined as partial response (PR) and stable disease (SD) for ≥6 months on clinical evaluation]. Results: A total of 47 patients were included, and the median follow-up time was 18.20 months. The median line of tucidinostat therapy was 3 (range, 1-9). In all, 52.17% patients were treated with tucidinostat plus fulvestrant, while 38.30% were treated with tucidinostat plus aromatase inhibitors. Notably, 10.64% of the patients with rapidly progressing visceral metastases received tucidinostat plus endocrine therapy as maintenance treatment after achieving disease control with chemotherapy. The median PFS was 4.43 months [95% confidence interval (CI), 2.77-10.53], and the median overall survival was 19.57 months (95% CI, 12.83-not reached). The 6-month CBR for the overall population was 41.86%. Patients undergoing maintenance therapy demonstrated a significantly longer PFS than did those who did not receive it as maintenance therapy (14.13 vs. 3.93 months; P=0.01). Univariate Cox regression analysis showed that use of tucidinostat in lines 1-2, use of tucidinostat plus fulvestrant, presence of one metastatic site, and lack of brain metastasis were favorable factors for PFS. Thrombocytopenia was the most frequently reported adverse event, with an incidence rate of 31.91% at all grades and 14.89% at grade ≥3. Four (8.51%) patients discontinued the treatment. Conclusions: For patients with HR+/HER2- ABC, tucidinostat combination therapy offers certain survival benefits with controllable safety. Furthermore, compared with non-maintenance therapy, maintenance therapy after chemotherapy may have promising efficacy.
RESUMO
Introduction: Palbociclib and ribociclib are indicated in the first-line treatment of hormonal receptor-positive HER-2 negative (HR+/HER2- negative) advanced breast cancer. Although randomized-controlled trials (RCTs) proved their clinical efficacy, there are no observational studies yet to validate the clinical findings in the real-world. Therefore, this study aimed to evaluate and compare the clinical effectiveness and safety profiles of palbociclib and ribociclib in Qatar. Materials and methods: A retrospective observational study was conducted on HR+/HER-2-negative stage-IV breast cancer patients receiving palbociclib or ribociclib in the state of Qatar. Clinical data were collected from the National Center for Cancer Care and Research (NCCCR) in Qatar using Cerner®. Primary outcomes were progression-free-survival (PFS) and overall-survival (OS) generated by Kaplan-Meier curves. Moreover, safety profiles of both two treatments were evaluated. Results: The data from 108 patients were included in the final analysis. There was no statistically significant difference in PFS between the palbociclib and ribociclib groups; PFS was 17.85 versus 13.55 months, respectively(p> 0.05). Similarly, there was no statistically significant difference in OS between the two medications, 29.82 versus 31.72 months, respectively(p>0.05). Adverse events were similar between the two groups. Neutropenia was the most common side effect in the study population accounting for 59.3% of the patients. Conclusions: Therefore, both treatments have similar efficacy and safety profiles. Further research on a larger-scale population and longer follow-up period is recommeneded.