4.4.2 Pharmacodynamics
Pharmacokinetic (PK) or pharmacodynamic (PD) correlates of clinical efficacy have not
been established for influenza. Two studies of peramivir in the influenza mouse model
suggested that the best predictor of efficacy was AUC, whether after oral or IV
administration. To investigate the relationship between peramivir dose and potential
metrics of clinical efficacy, such as plasma concentration above viral IC50 for a targeted
duration of time, the Applicant developed a population PK/PD model, details of which
are described here.