[18] A 2021 multicentre, randomised, double-blind, placebo-controlled, phase III trial of Soberana 02 showed acceptable vaccine efficacy against symptomatic COVID-19 and COVID-19–related severe infections.

[8] Professor Ihosvany Castellanos Santos said that the antigen is safe because it contains parts instead of the whole live virus, and therefore it does not require extra refrigeration, like other candidates in the world.

[8] In the ACS Chemical Biology article, scientists from Cuba explain details of the vaccines technology and production.

[21] The Cuban government says it is planning to produce 100 million doses of its vaccine to respond to its own demand and that of other countries.

[30] The roll-out began with an "Interventional Trial"[31] that consisted of inoculating 150,000 at-risk participants which seems to be defined as health-care workers.

The vaccine campaign using domestic products was heralded as a huge success by Cuban President Miguel Diaz-Canel when case loads were down significantly since January 2022.

The Soberana vaccine preparations were particularly effective in children, preventing 70,000 pediatric cases before the Omicron wave hit.

[36][37] Vietnam, Iran, Venezuela, Argentina,[38][39][40] Pakistan, India, the African Union, Jamaica, and Suriname[41] have expressed interest in purchasing the vaccine, following Phase 3 results.

[38][39][40] Additionally, the Cuban government offered a "transfer of technology" to Ghana and will also supply "active materials" needed to make the vaccine.

[49] FINLAY-FR-2, which started being developed in October 2020, had 40 volunteers for its Phase I, according to the Cuban Public Registry of Clinical Trials, with an open, sequential and adaptive study to assess safety, reactogenicity and explore immunogenicity of the vaccine.

[7] Phase III commenced at the beginning of March as originally scheduled,[54][27] and "ready to publish" results are expected by June.

[54] Although the trials involve thousands of adult volunteers recruited in Havana,[60] Cuba's public health officials have said that they will also need to conduct phase III trials abroad because the island doesn't have an outbreak of sufficient scale to produce meaningful statistics on vaccine protection.

[7][26] On March 13, 2021, the Cuban Biotechnology and Pharmaceutical Industries Business Group (BioCubaFarma) announced on social media that it had sent 100,000 doses of its Soberana 02 coronavirus vaccine candidate to the Pasteur Institute of Iran for clinical testing, "as part of the collaboration with other countries in the development of COVID-19 vaccines.