aDivision of Clinical Pharmacology, Johns Hopkins University School of Medicine, Baltimore, MD;

bDivision of Infectious Diseases, Johns Hopkins University School of Medicine, Baltimore, MD;

cJohns Hopkins Bloomberg School of Public Health, Baltimore, MD; and

dHealthcare Distribution Alliance, Washington, DC.

Correspondence to: Ethel D. Weld, MD, PhD, Division of Clinical Pharmacology, Johns Hopkins University School of Medicine, 600 North Wolfe Street, Osler 508, Baltimore, MD 21287 (e-mail: [email protected]).

C.W.H. has received research funding for clinical research and/or served on scientific advisory boards for Gilead Sciences, ViiV/GSK, Merck, Orion Biopharma, RTI, and Population Council. E.J.F. and C.W.H. are inventors on US Patents No. 10,092,509 and 10,646,434 owned by Johns Hopkins University, and both are founders of Prionde Biopharma, LLC.

We are grateful for the contributions of our study volunteers and the staff of the Drug Development Unit within the Division of Clinical Pharmacology.