Oncological diseases rank high in the structure of population morbidity and mortality. They entail considerable direct and indirect economic costs. In the past decades, the cost of oncotherapy has increased significantly, which is largely conditioned by high prices of antitumor drugs, which on average increased by ten times in the past ten years. At the same time, many innovative medications have only minor advantages over cheaper old medications because they are registered based on the data on the achievement of the surrogate endpoint – extension of progression-free survival. The high cost of oncotherapy is associated with financial toxicity that affects negatively the patients’ quality of life, their adherence to treatment and consequently survival. To reduce the cost of oncotherapy, it is necessary to conduct pharma-economic analysis, the results of which can serve as the basis to negotiate price-cutting with the manufacturers, as well as to use high-quality generics and biosimilars as effective and safe as their originals, and to monitor effectiveness and safety of all antitumor drugs within the pharmacovigilance framework.

The article discusses the role of second-generation androgen receptor inhibitors (ARi) in therapy of non-metastatic castration resistant prostate cancer (nmCRPC). The phase 3 trials PROSPER (enzalutamide), SPARTAN (apalutamide) and ARAMIS (darolutamide) showed that these medicines if used in combination with androgen deprivation therapy (ADT) make possible to significantly improve, as compared with placebo, metastasis-free survival and overall survival of patients with nmCRPC. An important role in choosing a certain medicine of the group is played by its safety profile, including its drug-drug interaction potential and effect on patient’s quality of life. In this respect, darolutamide has a number of advantages over apalutamide or enzlutamide. The frequency of CNS (cognitive, psychiatric, convulsive) and other adverse drug reactions that significantly worsen the patients’ quality of life (falls, fractures, hypertension, etc.) in therapy with darolutamide does not differ from that with placebo. Moreover, this medicine retains its antagonistic effects to all clinically significant androgen receptor mutations that develop resistance to enzalutamide and apalutamide.

The review discusses the interchangeability of medications, approaches to the registration of original and generic drugs, and types of their equivalence, as well as problems with generics in clinical practice. Results of pharmacoepidemiological studies, which have been widely carried out recently, speak of insufficient understanding of the impact of generics on remote outcomes of chronic diseases, including mortality. The longterm economic prospects of generic drug administration continue to remain unclear. Among the primary differences between generics and brandname drugs are the differences in active ingredient synthesis methods and the composition of adjuvants and additives. Comparative studies on the therapeutic equivalence of generics with their originals or between themselves are rarely conducted. They are often affected by methodological flaws, which cannot ensure their comparable efficacy and safety. In this regard, automatic replacement of drugs containing the same active ingredient should be avoided without the participation of the attending physician.