Kennedy Jr. rejected characterizations of him as an anti-vaxxer in a Senate hearing Wednesday where senators will weigh his confirmation as Health and Human Services Secretary—as his former billionaire running mate threatens to fund primary challenges against lawmakers who vote against him.

Robert F. Kennedy Jr. will undergo intense scrutiny over his history of controversial and inflammatory comments at his Senate confirmation hearing on Wednesday to become President Donald Trump’s Health and Human Services secretary.

RFK Jr. claimed he is not “anti-vaccine” and appeared unfamiliar with key aspects of healthcare insurance programs in his confirmation hearing.

In this week’s edition of InnovationRx, we look at HHS nominee Robert F. Kennedy Jr.’s first Senate confirmation hearing, the chaos at the NIH and with federal research funding, new dosages for an Alzheimer’s drug, a major tuberculosis outbreak, and more. To get it in your inbox, subscribe here.

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.

Robert F. Kennedy Jr. responded to tough questioning during his Senate confirmation hearings, defending his stance on public trust in health agencies, abortion, and vaccines. Despite criticisms over his past anti-vaccine activism,

Kennedy’s hearing Wednesday to be the nation’s top health official quickly devolved into an argument over the questions he’s raised for years about vaccine safety.