A pharmaceutical company plans to close its facility in Kansas City by the end of June, the Missouri Journal reported.

Sanofi-Aventis LCC plans to lay off 337 in Jackson County, according to a Worker Adjustment and Retraining Notification filing posted online by the Missouri Department of Economic Development.

The WARN Act requires employees to provide a 60-day notice in advance of covered mass layoffs.

Sanofi-Aventis first announced the closure of the manufacturing facility in Kansas City back in 2009, noting the closing of the site will happen in phases.

The global pharmaceutical company also has a manufacturing facility on the other side of the state in St. Louis County.

Employers across Missouri filed seven layoff notices last month, affecting 886 employees, compared to nine notices, affecting 2,429 workers, in March, the Missouri Journal reported.