 Shares in Accelerate Diagnostics surged almost 10 in extended market trading after the company said the US Food and Drug Administration FDA granted Emergency Use Authorization EUA for its COVID-19 antibody testing system.The stock soared to 16.30 in after-market trading on Tuesday. Accelerate Diagnostics AXDX said that following the FDA designation it will market and commercialize its COVID-19 serology-based testing platform. The MS-Fast system and BioCheck SARS-CoV-2 chemiluminescence tests process human serum samples in 30 minutes to detect antibodies that indicate recent or prior COVID-19 infection.This EUA will allow for more widespread adoption of the MS-Fast serology-based COVID-19 antibody testing platform, Jack Phillips, Accelerate Diagnostics CEO said. Serology testing is an important tool in the fight against COVID-19, as it enables the demographic and geographic surveillance necessary to guide an appropriate response to the current pandemic.Phillips added that the FDA approval marks the next phase in the companys plan to make a simple-to-use, scalable platform for COVID-19 serology testing available to all laboratories.The BioCheck SARS-CoV-2 IgM and IgG Combo Test targets the S1 protein, which is the major antigen of the novel coronavirus. The S1 protein has the fewest similarities to other coronaviruses, which allows for a lower probability of false positives due to cross reactivity, the company said.The S1 protein is also the primary target for the leading COVID-19 vaccines candidates, which are being developed to neutralize antibodies that can block the virus from infecting healthy cells, said Shelley Campeau, Accelerate Diagnostics Clinical Trials Manager. Several other EUA approved tests target the nucleocapsid N protein, but we believe the S1 protein antibodies are more likely to be protective against infection and are thus a more clinically relevant marker.AXDX shares are down 12 on a year-to-date basis mainly due to profit-taking over the past month.Looking ahead, the two analysts covering the stock see room for more upside. Piper Sandler analyst Rachel Vatnsdal earlier this month raised the stocks price target to 18 from 14 implying 21 upside potential and reiterated a Buy rating. Craig-Hallum analyst Alexander Nowak this month upgraded AXDX to Buy from Hold with a price target of 20. See Accelerate Diagnostics stock analysis at TipRanksMeanwhile, the average price target of 19 suggests room for 28 share appreciation over the coming year.Related News: Sorrento Dives 14 In Extended Trading After CFO Ousted Pfizer Inks Deal To Manufacture Gileads Covid-19 Remdesivir Treatment Krystals Promising Cystic Fibrosis Drug Scores Orphan Designation More recent articles from Smarter Analyst: Agilent Falls In Pre-Market As Quarterly Sales Miss; Oppenheimer Says Hold Australia Inks Deal With AstraZeneca For Supply Of Covid-19 Vaccine Candidate Verona Up 10 On Lung Trial Kick Off; Analyst Initiates Stock At Buy Etsy Declares 650M Convertible Note Offering; Stock Up 200 YTD 