Fig. 5
From: Development of an oral once-weekly drug delivery system for HIV antiretroviral therapy
Mathematical modelling of HIV treatment outcomes using long-acting antiretrovirals. a–h Viral dynamics modelling of HIV growth and evolution within individual patients. We consider a hypothetical weekly formulation, with identical peak concentration and 7-fold longer half-life a. Adherence patterns described in more detail in text and Supplementary Information. Patients are initially fully virologically-suppressed and failure is defined as two consecutive monthly viral load measurements > 200 c/mL in the year-long follow-up period. The height of the shaded area indicates the probability of outcome. Predicted patient outcomes versus adherence level (% of scheduled doses taken) for existing daily formulation of DTG (c) and RPV (f), and for long-acting versions, (d, g). Predicted outcomes for DTG (e) and RPV (h): a cohort of patients with a distribution of adherence levels taken from empirical data11, average adherence ~70% (b). C max is the peak drug level and is determined by the dosage size and absorption. 100% means that this value is the same for the hypothetical long-acting formulation as the existing one. i–j Epidemiological modelling of the impact of using oral long-acting antiretrovirals for PrEP in South Africa. The contours show the cumulative number of additional infections prevented (in thousands) by switching from daily to weekly oral PrEP formulation in South Africa by 2037. The x-axis depicts the supposed increase in efficacy (defined as reduction in per-exposure probability of infection), compared to a baseline efficacy of 50%. Solid lines indicating the plausible estimates (confidence intervals depicted as dashed lines) from meta-analyses respectively. The y-axis shows assumed increase in coverage (% of high-risk population receiving PrEP) assuming a baseline coverage of 30%. “Pessimistic ART” assumes current rates of ART use for treatment (i) while “Achieve 90-90-90” assumes increased rates (j)
