Safe and Effective: Use of Antiretroviral Treatments in Adults with Particular Reference to Resource Limited Settings: SECTION ONE. PRINCIPLES OF ANTIRETROVIRAL THERAPY (ART)*: 1.4. MONITORING

Safe and Effective: Use of Antiretroviral Treatments in Adults with Particular Reference to Resource Limited Settings
(2001; 36 pages) [French]

Table of Contents

	ACKNOWLEDGEMENTS
	INTRODUCTION
	SECTION ONE. PRINCIPLES OF ANTIRETROVIRAL THERAPY (ART)*
		1.1. BACKGROUND
		1.2. CHARACTERISTICS OF AVAILABLE ANTIRETROVIRAL DRUGS
		1.3. INITIATION OF THERAPY
		1.4. MONITORING
		1.5. TREATMENT FAILURE
		1.6. HIV RESISTANCE TO ANTIRETROVIRAL DRUGS
		1.7. FUTURE APPROACHES TO THERAPY
	SECTION TWO. SOME EXPERIENCES WITH ART IN RESOURCE LIMITED SETTINGS
		2.1. ART COVERAGE
		2.2. CONTEXT: PUBLIC OR PRIVATE SECTOR, DONOR SUPPORTED AND RESEARCH PROJECTS
		2.3. QUALITY OF CARE AND OUTCOMES
		2.4. LABORATORY MONITORING SERVICES
		2.5. SURVEILLANCE FOR DRUG RESISTANCE
		2.6. SUPPLY AND DISTRIBUTION OF THE DRUGS
		2.7. INITIATION OF TREATMENT
		2.8. CHOICE OF THERAPEUTIC REGIMEN
	SECTION THREE. GUIDE TO ART IN RESOURCE LIMITED SETTINGS
		3.1. WHAT SHOULD BE IN PLACE BEFORE INITIATING ART PROGRAMMES*
		3.2. COUNSELLING FOR ART
		3.3. CLINICAL EVALUATION BEFORE INITIATION OF ART
		3.4. INITIATION OF THERAPY
		3.5. MONITORING ANTIRETROVIRAL THERAPY*
		3.6. CONSIDERATIONS OF DRUG INTERACTIONS
		3.7. FURTHER RESEARCH NEEDS
		3.8. INFORMATION AND TRAINING NEEDS
	ANNEX I. LIST OF PARTICIPANTS
	ANNEX II. DRUG CHARTS

1.4. MONITORING

Response to ART is monitored clinically and biologically. The most important biological measurements are the concentration of HIV - RNA in plasma (the “viral load”) and CD4+ cell counts. These measurements correlate with clinical outcome.

The desirable “virologic” endpoint is a plasma viral load that is “below the limits of detection”, by the most sensitive assay being used, within 3 to 4 months of starting treatment and the achievement of a minimum decline from the baseline viral load of 1.5-2.0_log by the end of the first month of treatment. In patients with higher baseline plasma viral loads (e.g. above 100,000 copies/ml by RT-PCR) maximal suppression of viral replication may take a longer time.

When optimal response to therapy is achieved, the median CD4+ cell rise is 100 - 200 cells within the first year. The CD4+ cell response may lag behind the “virologic” response in timing and at times the two responses may even be discordant.

The optimal frequency of viral load monitoring is unknown. In general, plasma viral load is checked within 1 month of initiating therapy and two-monthly thereafter until the virologic goal of therapy, i.e. viral load below the limits of detection, is achieved. Following this, plasma viral load may be checked every 3 to 4 months.

Due to possible individual oscillations in the concentrations of HIV1-RNA and to variability in the assays in use, the baseline viral load measurement before initiation of treatment and any measurement thereafter that indicates a viral “rebound” significant enough to warrant considering a change in therapy, is routinely confirmed by a repeat test.

Table 2a. HIV-RNA measurements in monitoring antiretroviral therapy

HIV-RNA levels that suggest initiation of therapy	• above 30,000 copies/ml by RT-PCR
Target level of HIV-RNA after initiation of treatment	• “below the limits of detection” (at present taken as below 50 copies/ml RT-PCR) (< 400 copies/ml may be acceptable in some settings)
Timing of target response	• “below the limits of detection” within 3 to 4 months of initiating ART (in patients with high baseline HIV-RNA levels, maximal suppression may not be for 6-8 months)
Frequency of HIV-RNA measurements	• at baseline: 2 measurements 3-4 weeks apart • within 1 month of starting therapy to confirm antiviral activity of the regimen • every 2 months until viral load is below the limits of detection • every 3 to 4 months thereafter together with CD4 count (shorter intervals before critical decisions on therapy)