OpenAI has lost another C-suite executive, Fidji Simo, its number-two executive, who told the company she is leaving due to a worsened medical condition. Simo, who had been away from her full-time role due to an extended medical leave, is stepping down as CEO Sam Altman's right hand because her road to recovery will be much longer than originally anticipated. She has been battling a chronic neuroimmune condition called Postural Orthostatic Tachycardia Syndrome since 2019 and announced she was taking medical leave in April. Simo will continue as a part-time adviser. Her departure follows an April exodus of three top executives in one day: Kevin Weil, Bill Peebles, and Srinivas Narayanan. OpenAI has reportedly delayed its initial public offering to 2027 due to concerns about dwindling market enthusiasm and increased competition from rivals like Anthropic, whose Claude AI assistant has been gaining popularity. Anthropic has surpassed OpenAI's valuation for the first time. Separately, Reuters reported that Bank of America has extended a $520 million credit line to OpenAI ahead of its IPO.