Updated

A U.S. drug company backed by President Trump supporter Peter Thiel secretly conducted human trials for a herpes vaccine on the Caribbean island of St. Kitts — and the local government is now investigating, according to a report.

Thiel, the co-founder of PayPal, is one of several big-name investors who have backed the offshore testing of the experimental herpes inoculation by the company Rational Vaccines, The Daily Beast reported.

A former Hollywood filmmaker, who has not been identified publicly, was also a financial backer — and has claimed that the vaccine was successful during clinical trials, The Daily Beast reported.

The investment group kicked in at least $7 million for the research, and hoped to run tests in Mexico and Australia, according to the report.

The trials were reportedly performed in St. Kitts from April to August 2016 — without approval of the US Food and Drug Administration or the oversight of an institutional review board, also known as IRB — on a group of 20 people, mostly Americans.

St. Kitts officials told The Daily Beast the tests were conducted without government permission.

“The Ministry of Health states categorically that neither the Cabinet, the Ministry of Health, the office of Chief Medical Officer (CMO) nor the St. Kitts and Nevis Medical Board has ever been approached on this project,” a government press release said Wednesday night.

Agustín Fernández III, co-founder of Rational Vaccines, told The Daily Beast that his partner, William Halford, assured him he informed the St. Kitts government.

But Halford, a tenured professor at Southern Illinois University and lead researcher on the island project, died of cancer in June.

American researchers in recent years have opted to test new drugs abroad to cut costs. FDA rules require them to be monitored by an IRB or international equivalent when experimenting on humans.

Rational Vaccines claims there was little or no risk of the participants being harmed — because they already had herpes.

Still, experts told The Daily Beast that there is almost no chance of the vaccine being approved by the FDA, due to the fact that the company refused to follow American regulations or traditional safety rules.

“You can’t just ignore human-subject protections that have evolved since the end of the Second World War,” said Jonathan Zenilman, chief of Johns Hopkins Bayview Medical Center’s Infectious Diseases Division.

“What they’re doing is patently unethical,” he added. “There’s a reason why researchers rely on these protections. People can die.”

Thiel’s reps did not respond to Daily Beast requests for comment.