In the 1980s the drug became commercially available in East Germany, where it was marketed as Helpin by a pharmaceutical company called Berlin-Chemie. Only after the indication was changed to the treatment of herpes zoster in 2001 did it become more widely available in Europe.
The drug became accessible in East Germany during the 1980s, marketed as Helpin by Berlin-Chemie. It wasn't until 2001 that its use expanded to treat herpes zoster and gained wider availability across Europe.