ATLANTA, GEORGIA — Robert Malone resigned from the Advisory Committee on Immunization Practices on Tuesday afternoon. Malone, a former researcher turned outspoken anti-vaccine activist and conspiracy theorist, served as vice chair of the committee.

Health Secretary Robert F. Kennedy Jr. had hand-selected Malone to the Advisory Committee on Immunization Practices. Last June, Kennedy fired all 17 experts on the committee and populated it with anti-vaccine allies.

Last week, a federal judge temporarily blocked appointments to the Advisory Committee on Immunization Practices made by Kennedy, including Malone. The judge stayed changes that committee members had made to federal vaccine guidance and ruled that Kennedy's changes to the committee and the childhood vaccine schedule were likely illegal.

The judge claimed that Kennedy's appointees to the Advisory Committee on Immunization Practices were unqualified. Kennedy had made changes to the childhood vaccine schedule without input from committee members.

On Thursday, Malone claimed on social media that the Department of Health and Human Services had disbanded the Advisory Committee on Immunization Practices and planned to reconstitute it. Malone later retracted his claim and said that disbanding the committee was one of the options being considered.

Andrew Nixon released a statement saying that any assertions about HHS actions without an official announcement are baseless speculation. Following Nixon's statement, Malone announced his resignation.

"After Andrew trashing me with the press, I am done with the CDC and ACIP. That was the last straw," Malone said.

"Hundreds of hours of uncompensated labor, incredible hate from many quarters, hostile press, internal bickering, weaponized leaking, sabotage—I have better things to do," he said.

Martin Kulldorff, HHS chief science officer, contacted an outlet to confirm Malone's departure. "In light of the court ruling and the enormous amount of volunteer time provided by ACIP members to enhance public health, I can sympathize with Malone's decision to step away," Kulldorff said.

Joseph Hibbeln, an ACIP member, commented on Malone's resignation. "Contrasts with his prior dramatic and confusing statements," Hibbeln said. "It is good that Dr. Malone wishes now to decrease drama regarding vaccines."