In this instance a sponsor wishes to proceed to Phase 1 under an active IND where the drug is an antibody (1) drug conjugate. Because Ab1 is not an option for commercialization, the sponsor wishes to obtain an approved comparability protocol to substitute Ab2 in the same drug conjugate. The antibodies are considered identical and analytical data will be obtained to support a manufacturing change out of the antibody starting material. Keeping in mind the antibody in this drug is a specific delivery moiety, is comparability a reasonable approach. How likely is it the FDA would regard the Ab2 drug conjugate as a new drug?
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Barbara Araneo PhD
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