Clinical trials of a quadrivalent meningococcal vaccine completed in Russia

The Russian quadrivalent meningococcal conjugate vaccine MCV4-CRM197, localized by Petrovax Pharm through a full production cycle, has successfully completed Phase III clinical trials. The results confirmed that the product is comparable in efficacy to the foreign reference vaccine and offers advantages on certain measures of immune response and safety. Marketing authorization is to be obtained in summer 2026.

The clinical trial data were presented at the 12th Congress of the Euro-Asian Society for Infectious Diseases in St. Petersburg.

Bringing a domestic quadrivalent meningococcal vaccine to market is especially important given the rising incidence of the disease in Russia^[1]. Meningococcal infection is considered one of the most dangerous infections in the world: it can progress at lightning speed, and its case fatality rate reaches 15%^[2]. Up to 50% of patients who survive the invasive form of the disease are left with severe consequences^[3], including damage to the central nervous system, cognitive impairment, limb amputation, and other disabling complications. Those at greatest risk are young children, adolescents, and young adults, as well as people with weakened immunity^[4].

The clinical trial was conducted in 2025 at 18 research centers across Russia and enrolled 240 volunteers — both children and adults.

The study confirmed that the MCV4-CRM197 vaccine provides strong immune protection against the four most common meningococcal serogroups — A, C, W, and Y. Seroconversion rates ranged from 99.16% to 100%, comparable to the reference vaccine (98.33–100%).

At the same time, the MCV4-CRM197 vaccine produced a stronger immune response against serogroup C — one of the most epidemiologically significant serogroups. After a single dose, this response was 37% higher than with the reference product. Serogroup C is a frequent cause of outbreaks in kindergartens, schools, universities, and other communal settings, so these results may point to more reliable protection against it.

According to the study, the safety profile of the vaccine was comparable to that of the foreign reference product. In children, systemic post-vaccination reactions occurred half as often as with the foreign vaccine (in 20% of participants in the MCV4-CRM197 group versus 40% in the comparison group). No serious adverse events related to vaccination were recorded during the study.

Experts emphasize that the ability to prevent tragedy for a large number of Russian families depends directly on launching routine immunization against meningococcal infection without delay.

In January 2026, the Russian Ministry of Industry and Trade expanded Petrovax Pharm’s license to the production of the meningococcal vaccine. Once marketing authorization is obtained, expected this summer, the company plans to begin commercial production.

The MCV4-CRM197 vaccine is administered intramuscularly and provides simultaneous protection against all four principal meningococcal serogroups — A, C, W, and Y — which are responsible for the majority of severe cases worldwide. It is expected to be registered for use in children from three months of age and in adults up to 55 years of age. A vaccine based on this technology has been widely used around the world since 2021, and more than 3 million children have been vaccinated with it. The favorable safety profile confirmed in clinical trials supports its use in pediatric practice from three months of age.