Clinical efficacy of CDK4/6 inhibitor plus endocrine therapy in HR-positive/HER2-0 and HER2-low-positive metastatic breast cancer: a secondary analysis of PALOMA-2 and PALOMA-3 trials
Abstract
Summary Background Cyclin-dependent kinase 4/6 (CDK4/6) inhibitors in combination with traditional endocrine therapy (ET) are now the recommended first-line treatment for hormone receptor (HR)-positive and HER2-negative metastatic breast cancer (MBC). However, the benefits of adding CDK4/6 inhibitors to ET in HER2-low-positive and HER2-0 subgroups remain unclear. We aimed to assess the effectiveness of CDK4/6 inhibitors in combination with ET in patients with HR-positive, HER2-low-positive and HER2-0 MBC. Methods This secondary analysis assessed progression-free survival (PFS) among HER2-low-positive and HER2-0 patients enrolled in the double-blind, placebo-controlled randomised clinical trials PALOMA-2 and PALOMA-3. The study included 1186 HER2-negative, HR-positive female patients, with available immunohistochemistry (IHC) and/or in situ hybridization (ISH) results, across 17 countries enrolled between February 2013 and August 2014. HER2-low-positive status was defined by IHC 1+ or 2+ with negative ISH, and HER2-zero by IHC 0. Data analyses were conducted between March and May 2023. In the PALOMA-2 trial, patients were randomly assigned to receive either palbociclib or placebo, in combination with letrozole in the first-line treatment for HR-positive MBC. Patients in the PALOMA-3 study, who had progression or relapse during previous ET, were randomly allocated to receive either palbociclib plus fulvestrant or placebo plus fulvestrant. The primary endpoint was…
How strong is the evidence?
Evidence Hub reads this as a secondary / pooled analysis, done in people. Its evidence level is 3 of 5 (Moderate · trial / cohort / secondary analysis). Trials without a large randomized design, cohorts and secondary analyses give moderate evidence. Reported size: 666 participants or records.
Read the paper
Related studies
- Improving the translation of search strategies using the Polyglot Search Translator: a randomized controlled trial
- Nutritional, Physical, Cognitive, and Combination Interventions and Frailty Reversal Among Older Adults: A Randomized Controlled Trial
- Clinical characteristics and risk factors associated with COVID-19 severity in patients with haematological malignancies in Italy: a retrospective, multicentre, cohort study
- A randomized, controlled trial of oral propranolol in infantile hemangioma
- Clinical phenotypes of delirium during critical illness and severity of subsequent long-term cognitive impairment: a prospective cohort study
- Increased physical activity improves sleep and mood outcomes in inactive people with insomnia: a randomized controlled trial
Go deeper in Evidence Hub
Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.