Biotech firm Moderna Inc. could reap tens of billions of dollars in sales and stock appreciation if it wins the race for a COVID-19 vaccine. If it loses, the early-stage company’s value could crash.

In the meantime, the firm’s chief executive is pocketing millions of dollars every month by selling shares that have tripled in price on news of Moderna’s development progress, a Reuters analysis of corporate filings shows. The sales — by CEO Stephane Bancel, his childrens’ trust and companies he owns — amount to about $21 million between January 1 and June 26, including $6 million in May.

The company’s chief medical officer, Tal Zaks, has cashed out the majority of his available stock and options, netting over $35 million since January, the filings show.