US has funded Ukraine bio weapon research since 2005.

The agreement was entered into on August 29, 2005 in Kiev.

A publicly-available document shows a $15 million agreement signed between the US Department of Defense and Ukraine’s Health Ministry to support research into biological weapon research in Kiev, Lvov and Odessa.

https://www.state.gov/wp-content/uploads/2019/02/05-829-Ukraine-Weapons.pdf