The present disclosure relates to an antibody or antigen-binding portion thereof that binds to a filovirus. The antibody or antigen-binding portion thereof may have one or more murine CDRs and one or more human framework, regions. Also provided herein are compositions comprising the antibody or antigen-binding portion t hereof, methods of producing the antibody or antigen-binding portion thereof and methods of using the antibody or antigen-binding portion thereof.