The peptide Isoleucyl-valyl-threonyl-asparaginyl-threonyl-threonine (SEQ ID NO.1) is disclosed with its use as a pharmaceutical composition in reducing symptoms of viral disease and stimulating properties of immune system in a subject. A method is also disclosed for making a pharmaceutical composition comprising providing an Isoleucyl-valyl-threonyl-asparaginyl-threonyl-threonine (SEQ ID NO.1) peptide and mixing said peptide with a pharmaceutical acceptable carrier.