PURPOSE: This study investigated the impact of healthcare professional-led interventions on adherence to oral targeted therapy and identified the behavior change techniques (BCTs) underpinning the interventions. METHODS: A systematic search of MEDLINE, Embase, APA PsycInfo, CINAHL Plus, PubMed, and Web of Science up to July 2024 identified randomized controlled trials and cohort studies involving adult patients (≥ 18 years) with cancer on oral targeted therapy receiving healthcare professional-led interventions to improve adherence. Adherence-related outcomes, including proportions of patients continuing treatments or with a medication possession ratio (MPR) ≥ 90%, were compared between intervention and control (usual care) groups. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) and heterogeneity (I RESULTS: This review included 11 studies (1,654 patients). The pooled results for proportions of patients continuing treatment (OR 17.91
95%CI 3.18, 100.73
I CONCLUSION: Despite limited evidence, healthcare professional-led interventions significantly improve treatment adherence. Future studies should tailor strategies for individual needs and apply BCTs in designing effective interventions. PROSPERO registered: no. CRD42024571808.