This work was funded by a grant from the Swedish Research Council (grant no. 2021-04747). We thank ChemAxon for providing a free academic license, Optibrium for providing access to StarDrop and the Uppsala Drug Optimization and Pharmaceutical Profiling platform at the Department of Pharmacy, Uppsala University for the determination of logD for cyclosporin A and tacrolimus. We are grateful to P. Sjö at Drugs for Neglected Diseases initiative (DNDi) for helpful comments on the manuscript.