Promises and pitfalls for recombinant oligoclonal antibodies-based therapeutics in cancer and infectious disease.

•Heterogeneity and plasticity are key obstacles in cancer and infectious diseases.•Oligoclonal antibodies are uniquely suited to address and overcome these obstacles.•Numerous oligoclonal mAbs are being developed for cancer and infectious diseases.•Development of oligoclonal antibodies present significant, but surmountable challenges.•Strategies to overcome these challenges will have broad applicability across disease areas.