Selecta Biosciences, a clinical-stage biopharmaceutical company, signed a deal to extend its 27,833-square-foot headquarters lease at 480 Arsenal St. in Watertown, MA for an additional three years.

The company’s original lease was scheduled to expire on March31, 2017. The annual base rent will be $1.263 million beginning April 1, 2017, and will increase by three percent of the current base rent for 2018 and 2019.

Built in 1997, 480 Arsenal…