What happened Shares of Sorrento Therapeutics (NASDAQ: SRNE) were trading 5.5% lower as of 12:22 p.m. EDT on Wednesday. The morning's declines came after the company announced earlier that it had completed its acquisition of SmartPharm Therapeutics on Tuesday. So what Investors have known about Sorrento's plans to acquire SmartPharm since July 24. Were they disappointed with the decision? Nope. The biotech stock soared by more than 150% over the next few weeks before giving up the gains. Image source: Getty Images. So why did Sorrento's shares sink Wednesday? Part of the reason relates to how it's paying for the acquisition. The company issued around 1.76 million new shares to give to SmartPharm stockholders to close the deal, which diluted the value of the previously existing shares. But the number of new shares issued represents less than 1% of Sorrento's outstanding shares, so clearly, the closing of the SmartPharm deal wasn't the only driver of Wednesday's drop. It appears to be the continuation of a downward trend that began more than three weeks ago, stemming from the growing concerns among investors about Sorrento's prospects in the fast-moving COVID-19 therapeutics and vaccine markets. Now what Sorrento needs a clear win to turn things around -- and the FDA could hand it one or two in the not-too-distant future. The biotech is awaiting decisions from the regulator on an emergency use authorization for its COVI-TRACK novel coronavirus antibody test and on allowing it to initiate a phase 1 clinical study of its experimental antibody therapy, COVI-GUARD. 10 stocks we like better than Sorrento TherapeuticsWhen investing geniuses David and Tom Gardner have a stock tip, it can pay to listen. After all, the newsletter they have run for over a decade, Motley Fool Stock Advisor, has tripled the market.* David and Tom just revealed what they believe are the ten best stocks for investors to buy right now... and Sorrento Therapeutics wasn't one of them! That's right -- they think these 10 stocks are even better buys. See the 10 stocks *Stock Advisor returns as of August 1, 2020 Keith Speights has no position in any of the stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. The Motley Fool has a disclosure policy.Source