Whether the coronavirus vaccine developed by Moderna succeeds or not, executives at the small biotech company have already made tens of millions of dollars by cashing in their stock. An NPR examination of official company disclosures has revealed additional irregularities and potential warning signs. Since January, CEO Stéphane Bancel has sold roughly $40 million worth of Moderna stock; Chief Medical Officer Tal Zaks has sold around $60 million; and President Stephen Hoge has sold more than $10 million. The stock sales first came to widespread notice after Moderna announced positive early data from a vaccine trial in May. At that point, the company's share price jumped and official disclosures showed executives cashing in their shares for millions of dollars. Advocates have questioned whether it's appropriate for executives to privately profit before bringing the vaccine to market, especially when American taxpayers have committed roughly $2.5 billion to the company's vaccine development. Moderna says its executives pre-scheduled their stock sales long in advance. Those schedules - known as 10b5-1 plans - can act as a defense to charges of insider trading. But the plans have to be put in place when executives do not have confidential inside information. NPR has found multiple executives adopted or modified their plans just before key announcements about the company's vaccine. That has raised questions about whether they were aware of nonpublic information when they planned their stock trades.