One of the biggest names in the untamed world of cryptocurrencies, the Bahamas-based FTX exchange, was hurtling toward insolvency Thursday after its rivals scrapped plans to bail it out and customers scrambled to withdraw their assets before the final death knell.

The saga has dragged the price of bitcoin, the most popular cryptocurrency, down to levels not seen for at least two years, and has the potential to cost prominent backers of the platform — everyone from football star Tom Brady and prominent Wall Street banks to the Ontario Teachers’ Pension Plan — billions of dollars. As recently as January, the company was raising money at a valuation north of $32 billion.