Figure 4. Human mAb combinational therapy.

Two separate neutralizing epitopes that are prevalent on the envelope glycoprotein of a circulating virus are shown. Neutralizing antibody nAb1 and nAb2 can recognize the neutralizing epitope EI (nEI) and EII (nEII) on the circulating strain (row 1). The combination of nAb1 and nAb2 will provide broad neutralization activity and can prevent neutralization escape. A natural variant of nEII or neutralization escape mutant of nAb2 is still recognized by nAb1 (row 2) and nAb4. Likewise, a natural variant of nEI or neutralization escape mutant of nAb1 is still recognized by nAb2 (row 3) and nAb3. Both nAb3 and nAb4 are available and can be used to maintain two nAbs against circulating variant viruses. Only rarely would a combination of nAb3 and nAb4 be required (row 4).

Katie Ris-Vicari