Cuba launches Phase 3 trial of its COVID-19 vaccine. Earlier test results are still unknown

Cuba became the first country in Latin America to launch a Phase 3 trial with a homegrown COVID-19 vaccine Thursday, although the government has not yet released data from earlier testing.

“Our Sovereign, the first Latin American phase III vaccine!” wrote Cuban leader Miguel Díaz-Canel on Twitter on Thursday, referring to the vaccine known as Soberana in Spanish.

Other countries in the region have purchased vaccines or joined COVAX, a World Health Organization-backed initiative to ensure equitable distribution of shots worldwide. Cuba has an experienced biotechnology industry and is betting on the vaccine’s success as it tries to weather a severe economic contraction and an uptick in virus cases.

The government has set a goal of vaccinating the entire population of 11.3 million people this year in a bid to combat the pandemic and reopen the economy, which has been hit by travel restrictions and a reduction in tourism. The island appears to be positioning itself to also export the vaccine abroad and even attract visitors looking for a shot. A video that ran on state-controlled Venezuelan channel Telesur in January promoting “beaches, mojitos, and vaccines” featured Cuba’s top vaccine scientist, Vicente Vélez, saying tourists would be able to get the inoculation.

“It is a significant milestone,” Vélez said at a Thursday press conference. “It is incredible that a small country like Cuba, an island poor in material resources but very rich in human resources, has reached this point.”

Although news of the Cuban vaccine has offered hope to other countries in the region, such as Mexico and Jamaica, which have struggled to get shots and expressed an interest in acquiring it, experts warn that trials must follow international protocols and share results with the scientific community.

“We welcome any vaccine development in Latin America and the Caribbean. This effort by the Cuban government is certainly very relevant for the region,” said Dr. Jarbas Barbosa, deputy director of the Pan American Health Organization, at a press conference on Wednesday. But the official added that “we have to wait.”

Cuba is currently testing five coronavirus vaccine candidates.

Soberana 02 was developed by the state-run Finlay Vaccine Institute, and the final testing in a Phase 3 trial was approved on Wednesday by CECMED, the Cuban drug regulatory authority. Partial data available in a public registry for clinical trials indicates that the study, which aims to demonstrate the vaccine’s efficacy and safety in a wide group of people, will include about 44,000 volunteers in Havana between 19 and 80 years old.

The first Soberana 02 trials began in August with 900 volunteers. The results of the first two testing phases showed the inoculation’s “safety” and that “the vaccine is being effective against the virus,” said the director of CECMED, Olga Lidia Jacobo, at a press conference on Wednesday.

The trial protocol calls for administering two doses of Soberana 02 and one of Soberana 01, another vaccine candidate that is being studied to treat recovering COVID-19 patients. Soberana 02 works by combining a fragment of a protein in the “spikes” on the virus’ surface with a tetanus vaccine to generate an immune response.

In January, officials announced the final testing would also take place in Iran. An Iranian official said his country would also produce the Cuban vaccine.

Scientists involved in developing the vaccine said at a press conference Thursday that the country has the capacity to produce one to two million doses monthly of the vaccine, which would allow the population to be immunized within six months. They also said the country was working to scale up production for export. Previously, Vélez, the Finlay Vaccine Institute director, said that the country was preparing to produce 100 million doses.

Vélez said that results of the pre-clinical studies on Soberana 02 have been published but he did not share any of the findings. State media reported on preliminary and not peer reviewed findings suggesting that the vaccine induced a strong immunological response in mice. Vélez said data from human trials would be published in scientific journals in the future.

According to data from Cuba’s clinical trial registry, the study’s final results will not be published until early next year.

Barbosa, the PAHO deputy director, said the Americas branch of the World Health Organization cannot make any type of agreement for its distribution at this stage.

”Vaccines produced in all countries must meet the same requirements,” he said. “They must complete all pre-clinical and clinical trials, they must present a dossier that demonstrates the quality of production, that the vaccine is safe and is efficacious.”

Miami Herald reporter Jacqueline Charles contributed to this report.

Follow Nora Gámez Torres on Twitter: @ngameztorres