Drug bioavailability is a crucial aspect of pharmacology, affecting the effectiveness of drug therapy. Understanding how drugs are absorbed, distributed, metabolized, and eliminated in patients’ bodies is essential to ensure proper and safe treatment. This publication aims to highlight the relevance of drug bioavailability research and its importance in therapy. In addition to biochemical activity, bioavailability also plays a critical role in achieving the desired therapeutic effects. This may seem obvious, but it is worth noting that a drug can only produce the expected effect if the proper level of concentration can be achieved at the desired point in a patient’s body. Given the differences between patients, drug dosages, and administration forms, understanding and controlling bioavailability has become a priority in pharmacology. This publication discusses the basic concepts of bioavailability and the factors affecting it. We also looked at various methods of assessing bioavailability, both in the laboratory and in the clinic. Notably, the introduction of new technologies and tools in this field is vital to achieve advances in drug bioavailability research. This publication also discusses cases of drugs with poorly described bioavailability, providing a deeper understanding of the complex challenges they pose to medical researchers and practitioners. Simultaneously, the article focuses on the perspectives and trends that may shape the future of research regarding bioavailability, which is crucial to the development of modern pharmacology and drug therapy. In this context, the publication offers an essential, meaningful contribution toward understanding and highlighting bioavailability’s role in reliable patient treatment. The text also identifies areas that require further research and exploration.

The publication focuses on the innovative applications of PROTAC (proteolysis-targeting chimera) technology in modern pharmacotherapy, with particular emphasis on cancer treatment. PROTACs represent an advanced therapeutic strategy that enables selective protein degradation, opening new possibilities in drug design. This technology shows potential in the treatment of cancers, viral infections (such as HIV and COVID-19), and chronic diseases including atherosclerosis, Alzheimer’s disease, atopic dermatitis, and Huntington’s disease. Promising results from clinical studies on the compound ARV-471 confirm the effectiveness of this approach. New types of PROTACs, like TF-PROTAC and PhosphoTAC, are designed to enhance the effectiveness, stability, and absorption of treatment drugs. The conclusions of the review highlight the broad therapeutic potential of PROTACs in various diseases and their relevance for the future of therapies, particularly in oncology.