What question did this study set out to answer?

This meta-analysis aims to evaluate the adverse effects of CDK4/6 inhibitors with endocrine therapy in hormone receptor-positive breast cancer across different ethnicities.

May 24, 2026Open Access

462P Real-world effectiveness of 2nd-line treatments following 1L palbociclib + endocrine therapy: Preliminary results from the non-interventional study PERFORM

Key Points

This meta-analysis aims to evaluate the adverse effects of CDK4/6 inhibitors with endocrine therapy in hormone receptor-positive breast cancer across different ethnicities.
Real-world evidence analysis following PRISMA guidelines
Searches of MEDLINE and Embase included 116 studies on CDK4/6 inhibitors
Patients assessed for adverse effects by ethnicity and treatment type.
In over 23,700 patients treated with palbociclib, neutropenia was reported in 67%, with the highest rates among Asian patients (72%)
Abemaciclib showed significant ethnic variation in Grade 3 neutropenia, particularly higher in Asian patients (52.8%) compared to others
Ribociclib analysis revealed 45.8% of Asian patients experienced Grade 3 neutropenia with lower rates in White patients.

Abstract

Background: Cyclin-dependent kinase 4/6 inhibitors (CDK4/6i) with endocrine therapy are standard of care for hormone receptor-positive, HER2-negative metastatic breast cancer (HR+/HER2-MBC), although drug-specific adverse effect (AE) profiles vary.As clinical trials have limited ethnic representation, this meta-analysis uses realworld evidence to assess AEs associated with palbociclib, abemaciclib, and ribociclib across ethnic groups.Methods: Following PRISMA guidelines, MEDLINE and Embase were searched; 116 studies were included (Palbociclib: 67, Abemaciclib: 29, Ribociclib: 20).All estimates are reported with 95% confidence intervals (CI) unless specified otherwise.Results: Palbociclib 23786 patients (Asian (AS): 18124; White (WH): 4581; Black (BL): 347; Mixed Ethnicity (MX): 734; mean age: 57y) were included.Frequently reported AEs were neutropenia (67%), leukopenia (61%), and anaemia (31.5%).AS patients exhibited the highest incidence of neutropenia (72.0%) and leukopenia (76.7%), while BL and MX patients showed highest incidences of Anemia (33.8%).Metaregression showed ethnicity was not a significant moderator of AE risk (p > 0.05).Abemaciclib Among 4,715 patients (AS: 2,429; WH: 2,223; BL: 32; MX: 21; mean age: 62.4 years), considerable ethnic variation was observed in Grade 3 neutropenia.Incidence was higher in AS patients (52.8%) compared to WH (16%) and BL (12%).AS patients had the highest rates of leukopenia (77.4%) and anaemia (33.7%), while WH patients exhibit the lowest incidence across AEs.Ribociclib An analysis of 4,157 patients (WH: 2,189; AS: 1,514; BL: 131; MX: 323; mean age: 59.8 years) showed the highest incidence of Grade 3 neutropenia (45.8%; p < 0.0001), leukopenia, and anaemia in AS patients.WH patients had lower rates of haematological toxicity, while BL and MX cohorts showed intermediate incidence patterns. Conclusions:This meta-analysis identifies drastic ethnic disparities in haematological toxicity, particularly in AS.Results highlight the need for diverse RCT recruitment and standardised AE reporting to optimise personalised treatment.

KI fragen

Bookmark

View Full Paper