AAL 993 is primarily used in research settings for its immunosuppressive properties. It is known to modulate sphingosine-1-phosphate (S1P) receptor activity, which plays a key role in lymphocyte trafficking. This makes it a valuable tool in studying autoimmune diseases such as multiple sclerosis, type 1 diabetes, and inflammatory bowel disease. Due to its ability to reduce the circulation of lymphocytes, it has been investigated for potential use in organ transplantation to prevent graft rejection. Additionally, AAL 993 serves as a reference compound in pharmacological studies aiming to develop new S1P receptor-targeted therapies. Its application remains largely confined to preclinical research, where it helps elucidate immune system regulation and assess therapeutic efficacy in animal models.