Rintatolimod (brand name Ampligen) is an experimental drug in development for the treatment of a variety of chronic diseases and viral disorders, including Chronic Fatigue Syndrome or Myalgic Encephalomyelitis (ME).
The drug has not been authorised by the European Medicines Agency for the treatment of ME in the European Union. If the drug should receive marketing authorisation in Ireland, it would then be open to the marketing authorisation holder to make the drug available for prescribing, and to apply to the HSE to have the product reimbursed under the State drugs schemes.
I understand that the U.S. Food and Drug Administration (FDA) has declined to approve rintatolimod for use in the U.S., despite conducting several reviews of the drug over the last decade.