Grafalon 100mg injection contains active components as Human rabbit anti-T cell immunoglobulin. It is a medication used to treat severe graft-versus-host disease (GvHD). In GvHD, the donor's immune cells (T cells) attack the recipient's body cells. The donor's T cells see the recipient's cells as foreign. GvHD can affect any body part, but it most commonly affects the skin, liver, gut, and lungs. If you have had a severe allergic reaction to this medication or other monoclonal antibodies, you should not receive it.