Due to the vast economic consequences of classical swine fever (CSF) outbreaks, emergency vaccination plans are under discussion in European Union Member States. However, animals vaccinated with the conventional C-strain vaccine are subject to trade restrictions. To ease these restrictions, potent marker vaccines are required. One promising candidate is the chimeric pestivirus CP7_E2alf. For emergency vaccination in a CSF outbreak scenario, early onset of immunity is required. Here, the studies performed with a CP7_E2alf virus stock produced under good manufacturing conditions (GMP) are reported. In challenge experiments, CP7_E2alf induced full clinical protection 1 week after intramuscular vaccination, and 2 weeks after oral immunization. Furthermore, even after application of diluted vaccine preparations complete protection could be achieved if challenge infection was carried out 4 weeks after vaccination. In conclusion, GMP-produced CP7_E2alf proved to be a suitable marker vaccine candidate - also for emergency vaccination - both after intramuscular and oral application.