Key aspects of medication adherence to oral anticancer drugs: A literature review

At least 25% of the anticancer drugs are intended for oral use, while the creation and rapid introduction of oral drugs into clinical practice is constantly growing. Between 2006 and 2021, 80 oral forms of anticancer drugs were approved. It has been shown that patients prefer oral therapy to intravenous therapy if such a replacement is possible with equal efficacy and toxicity of the drugs. This once again emphasizes that the issue of adherence to treatment with oral forms is open and relevant for study. Currently, adherence, as the main factor in achieving the best clinical outcome, has been studied from different perspectives. However, there are no structured data globally, and, accordingly, evidence-based and specific recommendations in the absence of adherence. The review includes data from studies performed over the past 10 years, studying the adherence of patients to treatment with oral anticancer drugs. The data sources for the review were the Medline, Embase, and Scopus databases. Literature analysis showed that the most important aspects in the field of adherence to treatment with oral anticancer drugs include the level of patient adherence to treatment, factors affecting non-compliance, correlation of treatment adherence and clinical outcomes in malignant neoplasms. At the same time, the article considers the impact of non-compliance on the health care system as a whole. The most reliable and up-to-date data in the study area were examined to subsequently identify measures aimed at achieving the best practice in the organization of healthcare for patients with malignant neoplasms. The research results demonstrate the variability and heterogeneity of data, the lack of unified methodological approaches. In turn, this prevents the formation of objective and reliable conclusions about adherence. To make rational strategic decisions on monitoring adherence to treatment, it is necessary to initiate large-scale studies, adopt uniform standard procedures and recommendations for assessing adherence.