RedHill Biopharma Ltd. RDHL announced that the first patient was dosed in the phase II/III study of orally-administered RHB-107 (upamostat), an investigational new drug for patients with symptomatic COVID-19 who do not require hospital care. The study is being conducted in the United States.RHB-107 is a novel, potent inhibitor of serine proteases that targets human cell factors involved in preparing the spike protein for viral entry into target cells and is therefore expected to be effective against emerging viral variants with mutations in the spike protein.The phase II/III study (NCT04723527) is aimed at evaluating treatment with RHB-107 in patients with symptomatic COVID-19 early in the course of the disease, with a simple once-daily oral treatment in an outpatient setting.The first part of the study is designed for dose selection and will enroll 60 patients. The second part of the study is planned to enroll 250 patients and will evaluate time to sustained recovery from illness as the primary endpoint. Each patient will be tested for specific viral strains.Meanwhile, RedHill is also evaluating its second COVID-19 drug candidate, opaganib, in patients hospitalized with severe COVID-19. The phase II study of opaganib demonstrated safety and positive efficacy data across key primary and secondary endpoints. This study continues to enroll, having recently received a positive DSMB futility review. Top-line data and potential subsequent global emergency use authorization applications are expected in the second quarter of 2021.Shares of RedHill have rallied 34.1% in the year so far compared with the industry’s growth of 9%.Given the alarming levels of the spread and severity of the pandemic even after almost a year, quite a few pharma/biotechs are developing antibodies or evaluating their approved drugs or pipeline candidates to determine if they are effective enough to treat the infected patients. The emerging new strains pose a greater threat and the pharma/biotech companies are racing against time now.Regeneron’s REGN antibody cocktail, REGEN-COV (casirivimab and imdevimab), has also shown promise in this regard. Researchers and scientists have recently confirmed that REGEN-COV successfully neutralizes the circulating SARS-CoV-2 variants first identified in the U.K. (B.1.1.7) and South Africa (B.1.351).Earlier, Eli Lilly and Company LLY, Vir Biotechnology, Inc. and GlaxoSmithKline plc GSK announced a collaboration to evaluate a combination of two COVID-19 therapies in low-risk patients with mild-to-moderate COVID-19.Zacks RankRedHill currently carries a Zacks Rank #4 (Sell).You can see the complete list of today’s Zacks #1 Rank (Strong Buy) stocks here.Zacks Names “Single Best Pick to Double”From thousands of stocks, 5 Zacks experts each have chosen their favorite to skyrocket +100% or more in months to come. From those 5, Director of Research Sheraz Mian hand-picks one to have the most explosive upside of all.You know this company from its past glory days, but few would expect that it’s poised for a monster turnaround. Fresh from a successful repositioning and flush with A-list celeb endorsements, it could rival or surpass other recent Zacks’ Stocks Set to Double like Boston Beer Company which shot up +143.0% in a little more than 9 months and Nvidia which boomed +175.9% in one year.Free: See Our Top Stock and 4 Runners Up >>Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report Regeneron Pharmaceuticals, Inc. (REGN): Get Free Report Eli Lilly and Company (LLY): Free Stock Analysis Report GlaxoSmithKline plc (GSK): Free Stock Analysis Report Redhill Biopharma Ltd. (RDHL): Free Stock Analysis Report To read this article on Zacks.com click here. Zacks Investment Research