12 CLINICAL PHARMACOLOGY
12.1 Mechanism of Action
Protection against invasive meningococcal disease is conferred mainly by complement-mediated antibody-dependent killing of N. meningitidis. The effectiveness of Trumenba was assessed by measuring serum bactericidal activity using human complement (hSBA).
fHBP is one of many proteins found on the surface of meningococci and contributes to the ability of the bacterium to avoid host defenses. fHBPs can be categorized into two immunologically distinct subfamilies, A and B.1 The susceptibility of serogroup B meningococci to complement-mediated antibody-dependent killing following vaccination with Trumenba is dependent on both the antigenic similarity of the bacterial and vaccine fHBPs, as well as the amount of fHBP expressed on the surface of the invading meningococci.