Please tell me can drug induced immune system suppression reverse vaccinations?

Confusing question: During immunosuppression caused by a variety of drugs, the immune system is transiently reduced.It does not remove the biological memory created by vaccines.Once the drug or drugs are withdrawn, the immune system gradually returns with its memory intact.The exception would be the harsh chemo that is used to prepare one for bone marrow transplant. Those patients get their shots again after recovery