The judge in the Chloe Mitchell trial has discharged the jury.
Chloe Mitchell went missing in June 2023 and her remains were found days later.
Brandon Rainey, 30, formerly of James Street, Ballymena, has denied murdering her and preventing the lawful burial of her remains.
The trial began on Wednesday. The trial has been re-listed for the 25 November, when a new jury will be sworn in.
The judge has given no reasons for the decision. He said he will give his reasons in due course, after the conclusion of the trial.
He said "matters" had been brought to his attention and as a result, had made inquiries which meant the trial could not continue at present.
What happened to Chloe Mitchell?
The 21-year-old was last seen alive on CCTV in Ballymena town centre in the early hours of 3 June 2023 and an extensive search operation was launched by the PSNI.
Detectives investigating her disappearance later launched a murder inquiry after human remains were discovered in the County Antrim town.