COVID-19 vaccine made in Cuba.
While part of the world has already begun to vaccinate, Cuba waits for Soberana 01, Soberana 02, Mambisa or Abdala. The island's four vaccine candidates against COVID-19 are developed as subunit vaccines, one of the most economical approaches and the type for which Cuba has the greatest know-how and infrastructure. From protein S - the antigen or part of the SARS-CoV2 virus that all COVID vaccines target because it induces the strongest immune response in humans - Cuban candidates are based only on the part that is involved in contact with the cell's receptor: the RBD (receptor-binding domain) which is also the one that induces the greatest amount of neutralizing antibodies.
This strategy is not exclusive to Cuban vaccines. But Soberana 02 does distinguish itself from the rest of the world's candidates as the only “conjugate vaccine”. Currently in phase III clinical trials, it combines RBD with tetanus toxoid, which enhances the immune response. Apparently, with positive and early results, which have put it at the forefront of the Cuban race for the vaccine.
Cuba had already developed another vaccine with this principle. It is Cheimi-Hib, "the first of its kind to be approved in Latin America and the second in the world", against haemophilus influenzae type b, coccobacilli responsible for diseases such as meningitis, pneumonia and epiglottitis.
Competing interests: No competing interests