Robert F. Kennedy Jr. told senators he would apologize if data shows vaccines don’t cause autism, but he cited a poorly conducted study to counter the dozens that show they do not.

The man who hopes to be President Trump's Health secretary says he needs to see data showing vaccines are safe, but dismissed evidence shown by a Republican senator.

Kennedy Jr. is revising his ethics agreement to divest his interest in litigation against an HPV vaccine maker and directing the stake to his adult son, The New York Times reported Friday, citing a written response to questions from senators who are weighing his confirmation as Health and Human Services secretary.

Sen. Bill Cassidy, the top Republican on the Senate Committee on Health, Education, Labor and Pensions, concluded Thursday's hearing by saying he was "struggling" with the nomination due to Kennedy's vaccine positions. Kennedy notably refused to say vaccines don't cause autism as he faced pointed question from lawmakers.

If approved, Kennedy will control a $1.7 trillion agency that oversees food and hospital inspections, hundreds of health clinics, vaccine recommendations and health insurance for roughly half the country.

Democrats focused on Kennedy's anti-vaccine advocacy. Republicans probed the former Democratic leader on his abortion and agriculture views.

The top Republican on the Senate's health committee, Sen. Bill Cassidy, R-La., faced criticism from fellow Republicans after he suggested his vote for Robert F. Kennedy Jr.'s confirmation as Health and Human Services secretary is not a lock.