Varicella and Herpes zoster vaccines: from live attenuated vaccines to genetically engineered products

INTRODUCTION . Varicella zoster virus remains a serious threat to public health and is a sig­nificant burden on the health system due to treatment costs. Vaccination coverage against varicella zoster (VZ) and herpes zoster (HZ) remains low for a number of reasons, including lack of sufficient vaccines. Improving the existing vaccines, creating new genetically engineered, effective products with a high safety profile, and updating their assessment protocols (including cellular immune response parameters in the algorithms) is a prerequisite for further vaccine prevention of diseases caused by high-risk factors. Systematising status of VZ and HZ vaccines will help developers enhance preclinical and clinical research protocols. AIM . This study aimed to analyse the experience of developing and introducing modern vaccines to prevent diseases caused by varicella virus, as well as assessing the ways of further developments of preventive vaccines. DISCUSSION . Live vaccines are recommended for prevention of VZ and HZ, as they mimic the body’s natural immune response to a viral agent and activate both humoral and cellular immune responses. To date, seven live vaccines for VZ prevention and two live vaccines for HZ prevention are registered worldwide. However, under conditions of reduced immunity, live vaccines are not recommended due to high risk of vaccine-associated diseases. A recombinant glycoprotein E (gpE)-based vaccine with adjuvant system is indicated for HZ prevention in people over 50 years and allowed in immunocompromised patients. CONCLUSIONS . Research of vaccine development based on recombinant, RNA and DNA technologies shows the best prospects, since their safety is superior to live vaccines in a number of parameters and they can be used in immunocompromised patients. Both live attenuated and recombinant vaccines against diseases associated with the varicella virus are under development in Russia.