title: Authors' reply to the comment by Durg.
authors.affiliation: The George Institute for Global Health and Sydney Medical School, University of Sydney, Sydney, Australia.
authors.forename: C
authors.initials: C
authors.lastname: Abdel Shaheed
authors.affiliation: Faculty of Pharmacy, University of Sydney, NSW, Australia.
authors.forename: A J
authors.initials: AJ
authors.lastname: McLachlan
authors.affiliation: The George Institute for Global Health and Sydney Medical School, University of Sydney, Sydney, Australia.
authors.forename: C G
authors.initials: CG
authors.lastname: Maher