The immunogenic potential of a drug is a key aspect of its safety in clinical application and it is therefore assessed throughout the clinical drug development program. The clinical importance of knowing about immunogenicity is related to its potential side effects, e.g., influencing the drug’s PK, neutralizing the drug’s activity, supporting hypersensitivity or autoimmunity reactions, or cross-reacting with endogenous counterparts of the drug. In worst case the presence of anti-drug antibodies might be health- of life-threatening.