Distinguishing assay

A method for distinguishing in a sample an anti-drug antibody to a humanized anti-inflammatory drug antibody from an anti-human IgG antibody with an immunoassay, wherein the method comprises the following steps:

• a) providing
• a-i) a capture drug antibody, which is said drug antibody conjugated to a solid phase,
• a-ii) a tracer drug antibody, which is said drug antibody conjugated to a detectable label,
• b) contacting said capture drug antibody separately with
• b-i) said sample,
• b-ii) said sample, to which said drug antibody in monomeric form has been added,
• b-iii) said sample, to which said drug antibody in oligomeric form has been added,
• b-iv) said sample, to which human immunoglobulin G in monomeric form has been added,
• b-v) said sample, to which human immunoglobulin G in oligomeric form has been added,
• c) determining an anti-drug antibody to a humanized anti-inflammatory drug antibody by a positive immunoassay in b-i) and b-iv) and b-v) and a negative immunoassay in b-ii) and b-iii), or
• determining an antibody present in said sample to be an anti-human IgG antibody by a positive immunoassay in b-i) and b-ii) and b-iv) and a negative immunoassay in b-iii) and b-v).

A method for determining whether an anti-drug antibody in a sample is of monomeric or oligomeric form with an immunoassay, wherein the method comprises the following steps:

• a) providing
• a-i) a capture drug antibody, which is said drug antibody conjugated to a solid phase,
• a-ii) a tracer drug antibody, which is said drug antibody conjugated to a detectable label,
• b) contacting said capture drug antibody separately with
• b-i) said sample,
• b-ii) said sample, to which said drug antibody in monomeric form has been added,
• b-iii) said sample, to which said drug antibody in oligomeric form has been added,
• b-iv) said sample, to which human immunoglobulin G in monomeric form has been added,
• b-v) said sample, to which human immunoglobulin G in oligomeric form has been added,
• c) determining the anti-drug antibody in the sample to be of monomeric form by a positive immunoassay in b-i) and
• α) a negative immunoassay in b-ii) and b-iii), or
• β) a negative immunoassay in b-ii), b-iii), b-iv), and b-v),
• or
• determining an anti-drug antibody in the sample to be of oligomeric form by a positive immunoassay in b-i) and
• α) a negative immunoassay in b-iii), or
• β) a negative immunoassay in b-iii), and b-v),

A method for determining the kind of an antibody to a drug antibody present in a sample with an immunoassay, whereby the method comrprises the following steps:

• a) providing
• a-i) a capture drug antibody, which is said drug antibody conjugated to a solid phase,
• a-ii) a tracer drug antibody, which is said drug antibody conjugated to a detectable label,
• b) contacting said capture drug antibody separately with
• b-i) said sample,
• b-ii) said sample, to which said drug antibody in monomeric form has been added,
• b-iii) said sample, to which said drug antibody in oligomeric form has been added,
• b-iv) said sample, to which human immunoglobulin G in monomeric form has been added,
• b-v) said sample, to which human immunoglobulin G in oligomeric form has been added,
• c) determining an antibody present in said sample to be a specific, monomeric anti-drug antibody by a positive immunoassay in b-i) and b-iv) and b-v) and a negative immunoassay in b-ii) and b-iii), or
• determining an antibody present in said sample to be a specific, oligomeric anti-drug antibody by a positive immunoassay in bi) and b-ii) and b-iv) and b-v) and a negative immunoassay in b-iii), or
• determining an antibody present in said sample to be an unspecific, oligomeric anti-human IgG antibody by a positive immunoassay in b-i) and b-ii) and b-iv) and a negative immunoassay in b-iii) and b-v), or
• determining an antibody present in said sample to be an unspecific antibody by a positive immunoassay in b-i) and b-ii) and b-iii) and b-iv) and b-v), or
• determining an antibody present in said sample to be an unspecific, monomeric anti-human IgG antibody by a positive immunoassay in b-i) and a negative immunoassay in b-ii) and b-iii) and b-iv) and b-v).

A kit for determining an anti-drug antibody to a drug antibody in a sample comprising:

• a) a streptavidin coated micro titer plate,
• b) a reagent for conjugation of a drug antibody to biotin,
• c) a reagent for conjugation of said drug antibody to digoxigenin,
• d) a horseradish peroxidase conjugated anti-digoxigenin antibody,
• e) a reagent for oligomerization of said drug antibody,
• f) human immunoglobulin G in monomeric form and
• g) human immunoglobulin G in oligomeric form