Based on experience in research and production of recombinant vaccines, the Center for Genetic Engineering and Biotechnology (CIGB) is developing a project aimed at obtaining the Mambisa anticovid-19 vaccine, which is administered through the nasal route.
Unlike injectable vaccines, vaccines administered by this route stimulate local immunity in the nasal mucosa, the site of entry of SARS-CoV-2, which allows early neutralization of the pathogen.
The Mambisa vaccine candidate is a combination of two recombinant proteins: the RBD protein from the spike of the SARS-CoV-2 virus, and the nucleocapsid protein from the hepatitis B virus.
CIGB research has shown that the nucleocapsid protein of the hepatitis B virus has a powerful adjuvant effect in stimulating nasal immunity, which led to its use in the production and health registration of the HeberNasvac therapeutic vaccine against hepatitis B in 2015.
Both recombinant antigens are produced on expression platforms based on technologies used for more than 25 years for the production of proteins that have been shown to be safe, functional and effective as vaccines.
The Abdala vaccine was designed to stimulate a broad immune response that includes both systemic immunity (neutralizing IgG) and local immunity (mucosal IgA, T cells) in the nasal cavity and respiratory tract. Local mucosal immunity is important in blocking replication of the SARS-CoV-2 virus. in the nose, which is the starting point and spread of the disease.
Recent studies have shown that, in the absence of mucosal immunity, the nasal cavity can become a reservoir for the coronavirus, putting the patient at risk of reinfection or transmission of the disease to others. Nasal mucosal immunity is significantly stimulated by intranasal administration of a vaccine.
The CIGB developed an adaptive, randomized, parallel group phase I/II clinical trial to evaluate the safety and immunogenicity in adults of the Mambisa vaccine candidate in 120 volunteers convalescing from covid-19.
During phase I, three nasal administration devices were compared, two of them in the form of spray, and one in the form of drops.
With all three devices, Mambisa proved to be a safe vaccine. The adverse events that were described were mostly mild, and no serious events were described.
In all groups, Mambisa induced an anti-RBD response more than four times compared to the initial level, and the inhibitory capacity against the SARS-CoV-2 virus increased by more than 20%, at the systemic level and in the nasal mucosa. Currently, the stage of inclusion of volunteer subjects in a phase II clinical study is taking place.
In addition, the phase II Baconao clinical study is underway to evaluate the immunogenicity and safety of a booster dose with Mambisa in 2,220 individuals immunized with the CIGB Abdala vaccine.
Recent publications in important scientific journals around the world, as well as relevant immunology specialists worldwide, have pointed out the great prospects and potential advantages of nasal vaccines to combat the covid-19 pandemic. However, currently only 11 vaccine candidates are in clinical research phases, with the aim that they can be used by the nasal administration route, among which Mambisa has been recognized.
The CIGB vaccine candidate Mambisa is one of the immunogens for nasal use against covid-19 with the most advanced research in the world, and high safety, as it is based on protein antigens produced on a platform with a history of safe and effective use for more than 25 years.
The CIGB is a productive scientific complex that is part of the BioCubaFarma business group, dedicated to scientific research and innovation, development, production and marketing of products, applications, medicines and vaccines with high added value.
Its products and innovation projects focus on key areas of the biomedical sector such as the diagnosis, treatment and prevention of infectious, autoimmune, cardiovascular, cerebrovascular, oncological, dermatological, hematological, neurological, gastrointestinal, diabetes and healing diseases, as well as for the control of pests and diseases that affect various species and genera of plants and animals, including aquatic species.
The CIGB also works on the development of new businesses with foreign investment, and expands its links with other entities and with universities.
(With information from CIGB and BioCubaFarma)