What happened Sorrento Therapeutics (NASDAQ: SRNE), a clinical-stage biotech with an extensive COVID-19 product pipeline, is having a rough day today. The biotech's stock is down by a noteworthy 14% as of 10:54 a.m. EDT Wednesday. The culprit? Investors appear to be disappointed at Sorrento's COVID-19 pipeline and research and development update yesterday. Some shareholders seemingly had high hopes that the company would announce a game-changing event -- such as an emergency use authorization (EUA) for one of its plethora of COVID-19 pipeline candidates. Image source: Getty Images. So what Sorrento's stock has been on fire over the past few weeks leading into this pipeline update. The company, however, didn't give its investor base any groundbreaking news at this highly anticipated event. While Sorrento's braintrust did discuss the progress of its broad COVID-19 pipeline, management didn't provide any real insight into when any of these product candidates might be ready for public consumption. This lack of guidance on the commercial side of the ledger apparently gave short-sellers an opening to pounce on this red-hot biotech stock today. Now what Is Sorrento's stock worth buying on this hefty pullback? Sorrento has aggressively expanded into the COVID-19 arena this year, to be sure. But it still isn't considered a leader in any of the major medical fields dealing with the ongoing pandemic. As such, it might be best to hang back until the company's diversified COVID-19 pipeline produces a bona fide commercial-stage product. 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 September 24, 2020 George Budwell 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