Favoritism questions swirled around the Ministry of Food and Drug Safety (MFDS) after the regulator approved SK Bioscience’s phase 3 clinical trial of Covid-19 vaccine candidate GBP510 on Tuesday.

On Thursday, a local news report said the ministry granted the green light even though the participant enrollment plan for the trial did not meet the ministry’s guidelines of a Covid-19 vaccine study. In rebuttal, the ministry released a statement saying the guidelines were only recommendations, not mandatory.

Hankook Ilbo, a Korean vernacular daily newspaper, said the ministry went against the criteria for approving a phase 3 study when authorizing SK Bioscience’s phase 3 trial.

The guidelines for developing a local Covid-19 vaccine state that Korean nationals are recommended to account for 10 percent or more of the subjects in a global trial, the news report said. However, the number of Korean participants in the GBP510 clinical trial plan does not meet the guidelines recommended by the ministry, it added.

According to the phase 3 trial plan submitted to the MFDS by SK Bioscience, there are 93 Korean participants in the phase 3 study, where 3,990 subjects are expected to participate.

News reports said that SK Bioscience is mulling recruiting clinical participants in Eastern Europe and Southeast Asia for the multinational study.

The ministry released a statement immediately after Hankook Ilbo’s report.

“The 10 percent proportion of Koreans mentioned in the guidelines is a number that has been empirically recommended in general multinational studies. A company can set its proportion if it has data to prove consistency between countries based on statistical analysis,” it said. “The meeting of the expert advisory group on Monday concluded that SK Bioscience’s proposed number of local clinical participants was sufficient to confirm Koreans’ immunogenicity statistically.”

Vaccine industry officials showed mixed reactions to the latest controversy.

An official at a vaccine developer said he had mixed feelings.

“From a business point of view, it is good news that the government is relaxing related criteria,” he said. “If there was no issue in proving safety and efficacy in clinical design, there is no reason to reject the trial plan.”

However, another official in the vaccine industry said the government’s approval was absurd.

It is applaudable that SK Bioscience secured a control vaccine from AstraZeneca because it showed the company’s capabilities, but the government’s stance has been too inconsistent, the official said.

“It seems absurd to authorize a phase 3 study when SK Bioscience has not even finished the phase 2 trial,” he added.