U.S. Department of Defense claims they targeted three chemical weapons facilities with 105 missiles.
One of the three targets, Barzah, had 76 missiles (66% of all missiles) used against it, according to DOD.
OPCW cleared Barzah between November of 2017 and February of 2018 as not being in violation of the chemical weapons convention.
Workers at Barzah claim they were working on antidotes to scorpion and snake venom.
https://www.opcw.org/fileadmin/OPCW/EC/87/en/ec87dg21_e_.pdf
https://www.afp.com/en/news/826/destroyed-syria-lab-workers-deny-producing-toxic-weapons-doc-1411by1