The federal order temporarily halts the Trump administration’s plans to slash $4 billion in overhead costs for research at universities and medical centers into diseases like cancer.

Robert F. Kennedy Jr. also disclosed that he had reached at least one settlement agreement with a company or individual that has accused him of “misconduct or inappropriate behavior.”

Senators had objected to the financial conflict posed by Robert F. Kennedy Jr.’s decision to retain a financial stake in lawsuits against a major drug company. It remains unclear whether any proceeds would be redirected.

If confirmed as health secretary, Robert F. Kennedy Jr. would oversee the Food and Drug Administration and other agencies that issue key decisions for drug companies.

In a scathing letter to lawmakers weighing Robert F. Kennedy Jr.’s nomination for health secretary, Ms. Kennedy called her cousin unfit for the job and a “predator” who led family members to addiction.

In the final days of the Biden administration, the F.D.A. is moving ahead with a proposal to require companies to produce a less addictive product for traditional smokers.