New court documents show a former ISU researcher in the Department of Biomedical Services has agreed to plead guilty to scientific fraud, according to documents filed in U.S. District Court.

Dong-Pyou Han originally pleaded not guilty in June 2014 to four felony counts of making materially false, fictitious or fraudulent statements about a matter under the jurisdiction of a branch of the United States government. The charges carry fines and up to five years imprisonment.

The details of the plea agreement were not specified in the document filed Jan. 16 by Joe Herrold, Han’s public defender. Kevin Vander Schel, a spokesman for the U.S. attorney’s office, said prosecutors don’t release details of a plea agreement until it is formally filed in court.

After admitting he’d faked results of experiments with an AIDS vaccine in 2013, Korean-born Han was forced to resign his position as a research assistant professor. He admitted to mixing human antibodies with the blood of rabbits to make it look like the vaccine was protecting the rabbits against HIV, the virus that causes AIDS.

The falsified research originally brought in millions of dollars in federal grants, but Iowa State has since been forced to repay $496,000 to the federal government and another $1.4 million in grants have been canceled.

According to the court documents, Han “is currently on pretrial release in the state of Indiana, and, due to a health problem, is not able to drive to Iowa for change of plea proceedings.”

Herrold also asked for extra time to find a qualified Korean interpreter and “provide the defendant with sufficient time to obtain a reasonably priced flight,” which the document states Han plans to purchase himself.

Han’s trial was set to begin Feb. 2, but has been granted a continuance. A jury trial is now scheduled to begin March 2, marking the fourth time a continuance has been granted.

ISU officials have said Han was the lone culprit in the the fraud and the team will continue their research to find an AIDS vaccine.