History of antibody therapy
In 1890, Behring and his team discovered that the serum obtained from a rabbit infected with diphtheria was effective in preventing the diphtheria infection (awarded Nobel Prize in 1901). Later, it was revealed that the effect was due to antibodies contained in the serum. However, some problems arose...
Serum therapy was initially less effective than current antibody therapeutics and also had substantial side effects. (Because substances other than antibodies were contained in the serum.)
Separation of antibody fraction from serum.
Even after the separation, antibody fraction contained unintended antibodies and impurities that could not be removed, the sufficient effect could not be obtained and there were also side effects.
Human body created the antibody against the administered mouse antibody, which lead to the insufficient efficacy and remaining side effects.
Mouse antibodies with a high level of antigenecity have evolved into low antigenic chimeric antibodies, humanized antibodies and fully human antibodies.