One of the last big IPOs of the year just got delayed as the short-lived rebound in the new-issue market unravels.

Waystar was set to launch its roadshow to pitch investors this week, but now is not expected to do so until December at the earliest, people familiar with the matter said. The healthcare-payments company, which at one point was expected to fetch a valuation in the high-single-digit billions, will likely wait until 2024, some of the people said.