As the coronavirus outbreak continues to spread, some of the biggest drug companies are moving closer to finding a vaccine.Biotech giant Gilead Sciences GILD is planning to administer its remdesivir drug to patients next month. Remdesivir is an experimental drug that has been used to treat Ebola. The World Health Organization (WHO) believes it may be the best chance to effectively treat the coronavirus.Novavax NVAX and Moderna MRNA are also working on vaccines, and both companies expect to begin phase 1 studies soon. Drugmaker Sanofi SNY recently announced plans to develop a vaccine; it said it will leverage previous work for a SARS pre-clinical vaccine. Other large drug makers like GlaxoSmithKline GSK and Johnson & Johnson JNJ are working on vaccines as well.Scientists are hoping to cut the time it takes to develop a vaccine in half—which used to take years, since the virus had to be grown in a lab—with a new tool that builds a vaccine based on a virus’ genetic sequence. Researchers are hoping to have a viable preventive by this fall.We are reissuing this article to correct a mistake. The original article, issued February 28, 2020, should no longer be relied upon.Looking for Stocks with Skyrocketing Upside?Zacks has just released a Special Report on the booming investment opportunities of legal marijuana.Ignited by new referendums and legislation, this industry is expected to blast from an already robust $6.7 billion to $20.2 billion in 2021. Early investors stand to make a killing, but you have to be ready to act and know just where to look.See the pot trades we're targeting>>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 Johnson & Johnson (JNJ): Free Stock Analysis Report Sanofi (SNY): Free Stock Analysis Report Gilead Sciences, Inc. (GILD): Free Stock Analysis Report Moderna, Inc. (MRNA): Free Stock Analysis Report GlaxoSmithKline plc (GSK): Free Stock Analysis Report Novavax, Inc. (NVAX): Free Stock Analysis Report To read this article on Zacks.com click here. Zacks Investment Research