Cardiotoxicity of HER2-Targeted Drugs When Combined with Other Drugs: A Systematic and Meta-analysis of Randomized Controlled Trials.

The development and use of HER2-targeted drugs has improved the prognosis of HER2-positive cancer patients. However, in addition to improved survival rates, treatment-induced adverse events and nontumor-related deaths have increased. We sought to assess the incidence of cardiovascular adverse events when HER2-targeted drugs are combined with other drugs. We systematically searched the literature on the cardiotoxicity of anti-HER2 drugs in electronic databases, including PubMed, Web of Science, Cochrane Library, OVID and CNKI, from their inception to April 2022. The Cochrane Collaboration's tool for assessing risk of bias and the Jadad scale were used to evaluate the risk of bias and quality of the studies, respectively. For each included trial, we calculated the incidence of cardiovascular adverse effects (CAEs) and 95% confidence intervals (95% CIs) and performed a meta-analysis using a random effects model (REM). The meta-analysis was performed using R 4.2.1. We included 41 randomized clinical trials (RCTs) in the meta-analysis, consisting of 56 groups and 31,934 patients. The meta-analysis revealed the following: (1) The incidence of cardiotoxicity in groups given monoclonal antibody treatment was 14% for single therapy (95% CI: 2-34%) and 10%, 11%, and 12% for adjuvant therapy combined with combined therapy (95% CI: 6-13%), chemotherapy (95% CI: 8-13%) and endocrine therapy (95% CI: 7-18%), respectively. However, in the groups treated with the antibody‒drug conjugates (ADCs), the percentage of patients treated with the combination therapy was 1% (95% CI: 0-2%) and 5% (95% CI: 4-7%), respectively, with a significant difference (P < 0.01). The heterogeneity among the included studies was significant (I² = 94%, p < 0.01). (2) When monoclonal antibodies were combined with chemotherapy, the incidence of cardiotoxicity under anthracycline-containing therapy (10.3%) was significantly greater than that under nonanthracycline-containing therapy (8.8%). (3) Significant differences were found between subgroups, except for the endocrine group versus some others, although this difference might result from the different inclusion criteria of the original trials. (1) When anti-HER2 drugs are administered in combination with anthracycline-containing chemotherapy, the incidence of cardiotoxicity is greater than with other drugs. (2) Safety benefits can be achieved by replacing traditional monoclonal antibodies with ADCs. The comprehensive use of these drugs necessitates collaboration between oncologists and cardiologists.