4. Discussion and conclusion
Results of the current study suggest that PBPK modelling successfully predicted plasma concentration-time profiles of chloroquine and lopinavir (LPV/r) when given alone, or in combination. The results suggest that there is a weak but potentially significant DDIs between chloroquine, and LPV/r. Using PBPK modelling can guide the selection of appropriate dose regimens in terms of both efficacy, and safety. Simulations of several dosage regimens of chloroquine administration alone, and when co-administered with lopinavir (LPV/r) offer potential dose optimization strategies for the treatment regimen for COVID-19 infected patients.