Compartment modeling to understand depot pharmacokinetics in humans. a) two compartment model schema with first-order kinetics between compartments, including relevant physiological parameters and antibody drug characteristics. Pharmacokinetic profiles were generated for antibodies with different elimination half-lives to simulate antibody release from subcutaneous depots exhibiting different release rate constants: b) IgM class antibodies, c) VRC01, an anti-HIV bnAb, d) REGN-COV2, antibody cocktail against SARS-CoV-2, and e) mAb-LS, indicating a bnAb modified with the LS mutation to increase serum half-life. Arrows on bars indicate that serum titer remained above the 3 μg/mL threshold beyond 365 days.