Shares of Moderna Inc. /zigman2/quotes/205619834/composite MRNA -3.75% gained 0.5% in premarket trading on Thursday after the drugmaker announced another manufacturing deal for its still investigational COVID-19 vaccine. As part of the deal, Laboratorios Farmacéuticos Rovi /zigman2/quotes/201694325/delayed ES:ROVI +0.73% , based in Madrid, will handle commercial fill-finish manufacturing of the vaccine candidate for use outside of the U.S. The company's vaccine candidate has not yet proven that it can protect against the coronavirus; however, drugmakers in the U.S. are moving forward with manufacturing plans often with the financial support of the U.S. government to speed up the vaccine development process. Moderna has announced several manufacturing deals for its experimental COVID-19 vaccine, including with Catalent Inc. /zigman2/quotes/206700489/composite CTLT -2.59% and CordenPharma. Moderna's stock has gained 214.8% since the start of the year, while the S&P 500 /zigman2/quotes/210599714/realtime SPX -0.37% is down 1.8%.