Therapeutic Drug Monitoring in HIV
OverviewHow to Order
To optimise drug regimens for the individual patient

Typically 20-50% patients in clinic have sub-therapeutic plasma concentrations of PIs and NNRTIs, while the inter-individual variability in plasma concentrations is immense (=100-fold difference) despite standard dosing. Therapeutic drug monitoring (TDM) is used to optimise drug regimens for the individual patient by increasing efficacy and avoiding drug-related toxicity. TDM for HCV drugs is also available from Lab21.

Lab21 is committed to providing the highest quality services to our customers, and test turnaround time is only 14 working days from the receipt of sample at Lab21.

HIV TDM from Lab21

Protease Inhibitors
Amprenavir, Atazanavir, Darunavir, Indinavir, Lopinavir, Nelfinavir, Ritonavir, Saquinavir, Tipranavir

NNRTIs
Efavirenz, Etravirine, Nevirapine

NtRTI
Tenofovir

Integrase Inhibitor
Raltegravir

Fusion Inhibitor
Enfuvirtide (T-20)

CCR5 Antagonist
Maraviroc

To view antiretroviral target values: HIV TDM Antiretroviral Target Values.

Not just a number

In addition to the concentration of the requested drugs, Lab21 TDM results include a clinical interpretation based on a validated algorithm. A database of reporting algorithms has been created by Professor David Back (University of Liverpool) and associates. The algorithms are developed, reviewed and updated by an international panel of experts in pharmacology and HIV therapy. Each Therapeutic Drug Monitoring report supplements the drug concentration level(s) with comments designed to assist the treating physician in interpreting the result.

Information on drug-drug interactions, and on the work of Professor Back and associates, can be found on the Liverpool HIV Pharmacology Group web-site at www.hiv-druginteractions.org.

Not just trough samples
 
Lab21 will accept all samples taken >4h after drug administration. If they are not trough samples we will estimate the trough concentration, where possible, either by projection based on population half-life data or based on population PK (percentile) data.

Pharmaceutical schemes

TDM is sponsored by Merck Sharpe & Dohme (MSD) for Indinavir in cases of suspected toxicity. Please contact your MSD representative for full details.

Reference
  1. Boffito M et al. Current status and future prospects of therapeutic drug monitoring and applied clinical pharmacology in antiretroviral therapy. Antiviral Therapy, 2005; 10: 375–392.
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