Facilitating compound progression of antiretroviral agents via modeling and simulation

Antiretroviral pharmacology in mucosal tissues

Strategies to prevent HIV infection using preexposure prophylaxis are required to curtail the HIV pandemic. The mucosal tissues of the genital and rectal tracts play a critical role in HIV acquisition, but antiretroviral (ARV) disposition and correlates of efficacy within these tissues are not well understood. Preclinical and clinical strategies to describe ARV pharmacokinetic-pharmacodynamic relationships within mucosal tissues are currently being investigated. In this review, we summarize the physicochemical and biologic factors influencing ARV tissue exposure. Furthermore, we discuss the necessary steps to generate relevant pharmacokinetic-pharmacodynamic data and the challenges associated with this process. Finally, we suggest how preclinical and clinical data might be practically translated into optimal preexposure prophylaxis dosing strategies for clinical trials testing using mathematical modeling and simulation.

A sensitive and rapid liquid chromatography-tandem mass spectrometry method for the quantification of the novel neurokinin-1 receptor antagonist aprepitant in rhesus macaque plasma, and cerebral spinal fluid, and human plasma with application in translational NeuroAIDs research

A sensitive and rapid liquid chromatography-tandem mass spectrometry method has been developed for to assess therapeutic exposures of aprepitant in HIV-infected patients and rhesus macaques. The method utilized a simple sample-preparation procedure of protein precipitation with methanol. Chromatographic separation was performed on a reversed phase C(8) column (Hypersil Gold, 50 mm x 2.1 mm, 3 microm) using a mobile phase composed of acetonitrile and water in 0.5% formic acid through gradient elution. Electro-spray ionization in positive mode was incorporated in the tandem mass spectrometric detection. The lower limit of quantitation of aprepitant in plasma of rhesus macaques and human and cerebral spinal fluid of rhesus macaques were 1, 1, and 0.1 ng/mL, respectively. The method has been successfully employed to measure aprepitant in preclinical and clinical samples collected from three SIV-infected rhesus macaques and ten patients with HIV infection. In conclusion, this liquid chromatography-tandem mass spectrometry method is suitable for preclinical-clinical translational research exploring exposure-response relationships with aprepitant as well as therapeutic drug monitoring of aprepitant.

The role of quantitative pharmacology in an academic translational research environment

Translational research is generally described as the application of basic science discoveries to the treatment or prevention of disease or injury. Its value is usually determined based on the likelihood that exploratory or developmental research can yield effective therapies. While the pharmaceutical industry has evolved into a highly specialized sector engaged in translational research, the academic medical research community has similarly embraced this paradigm largely through the motivation of the National Institute of Health (NIH) via its Roadmap initiative. The Clinical and Translational Science Award (CTSA) has created opportunities for institutions which can provide the multidisciplinary environment required to engage such research. A key component of the CTSA and an element of both the NIH Roadmap and the FDA Critical Path is the bridging of bench and bedside science via quantitative pharmacologic relationships. The infrastructure of the University of Pennsylvania/Children's Hospital of Philadelphia CTSA is highlighted relative to both research and educational objectives reliant upon quantitative pharmacology. A case study, NIH-sponsored research program exploring NK1r antagonism for the treatment NeuroAIDS is used to illustrate the application of quantitative pharmacology in a translational research paradigm.