haart: where we’ve come, and where we’re going
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HAART: Where we’ve HAART: Where we’ve come, and where we’re goingcome, and where we’re going
Jeffrey B. Greene, MD
Chairperson- MCCC
AIDS Institute
H.A.A.R.T.
Highly
Active
Anti-
Retroviral
Therapy
1994-5: The HAART stage was set
• Concorde Study
• ACTG studies of dual nucleosides
• Availability of reliable tests of viral load
• Link between viral resistance and success of therapy
• Saquinavir- 1st of a new class of antiviral
The Birth of HIV/AIDS Therapeutics
0
2
4
6
8
10
12
14
16
Number of Available Agents
1987 1989 1991 1993 1995 1997 1999
Lopinivir
Amprenavir
Abacavir
Efavirenz
Delavridine
Neviripine
Nelfinivir
Indinivir
Ritonivir
Saquinivir
DDC
D4T
3TC
DDI
AZT
Short-term Clinical Effects of HAART
• Resolution of HIV-induced symptoms• Marked reduction of HIV load in plasma• Increase in CD-4 cell counts• Control of active O.I.’s (e.g.: MAC, CMV)• Reduction in the incidence of new O.I.’s• Reduction of hospital days, and need for home IV
therapies/ nutrition• 50% reduction in mortality rate in NY
Change in the treatment paradigm
The success of therapy was assessed by laboratory outcomes, instead of
clinical outcomes
TREAT HARD ! TREAT HARD ! TREAT EARLY!TREAT EARLY!
It’s the Virus, STUPID!
• Frequent alterations of regimen to address “bumps” in viral load
• Increasing doses of antiviral agents
• Adding pharmacologic enhancers to increase blood levels of antivirals (e.g.- Indinivir + Ritonivir)
• “Mega-HAART”
Keeping the Goals of Therapy in Focus
Successful Treatment/ At the
Expense of the Patient?
Limitations of Aggressive HAART
• Pill burden
• Food and storage restrictions
• Drug- drug interactions
• Severe side-effects
• Reduction in Quality of Life measures
• Emergence of multiple drug resistance mutations
Optimal HAART Requires Optimal Adherence
• Understand patient-specific issues
• Deal with patient concerns
• Weigh efficacy against toxicity
• Build a trusting provider/ patient relationship
Defining “Optimal” Adherence
• 95% accuracy in dosing– e.g.- missing no more than 3/ 60 doses/ month
in a b.i.d. regimen
• Respecting dietary restrictions
• Proper storage of medication
• Avoiding co-therapies that might alter the
HAART blood levels
Helping Patients Juggle The Therapies
• Trusting provider relationships
• Ongoing patient education
• Utilize entire support team
• Simply regimens
• Dosing reminders (pill boxes, alarms, beepers)
Helping Providers Juggle the Therapies
• Know what therapeut-ic response to expect
• Anticipate toxicity and monitor for it
• Set reasonable treat-ment goals for patient
• Understand and consider drug-drug interactions
Lopinivir(Kaletra™) + Neviripine (Viramune ™)
ABBOTT Labs
Effect of Lopinivir on Viramune- None
Effect of Viramune on Lopinivir- Negligible
Recommendation: No change in
recommended doses
Boheringer-Ingleheim
Effect of Lopinivir on Viramune- None
Effect of Viramune on Lopinivir- 25% reduction in levels
Recommendation: Increase dose of
Lopinivir
Resist the urge to try the
“Drug-de-Jour”
Long term toxicity of HAART
• Hypercholesterolemia, Hypertriglyceridemia• Diabetes mellitis• Atherosclerotic cardiovascular and
cerebrovascular disease• Lipodystrophy, fat- redistribution• Lipoatrophy• Lactic acidosis• Osteoporosis
Initiating HAART
Then (1998)
• HIV symptoms• CD-4 counts < 500• HIV-1/PCR > 10K
Now (2001)
• HIV symptoms• CD-4 counts < 350• HIV-1/PCR > 20-30K
Reasons for changing successful HAART
• Drug Toxicity (e.g.- neuropathy, pancreatitis, renal stones, diarrhea/ nausea, insomnia/ neuroirritability, lipoatrophy, fat redistribution, diabetes, lipid abnormalities)
• Quality of Life issues (e.g.- conflict of schedules, privacy, refrigeration)
• Fear of long-term adverse drug reactions
Definition of Failing HAART
• Incompatible with proper adherence
• Less than a 1.5- 2.5 log drop in viral load
• Rising viral load after an initial drop
• Falling CD-4 counts
• ? CD-4 counts that do not increase from baseline?
• Continued HIV-associated symptoms
Factors Favoring Mutational Drug Resistance
• Rapid rate of spontaneous mutation• Low therapeutic margins of many drugs• Erratic pharmacokinetics• Cross- resistance within classes• Providers with low index of suspicion• Prior exposure to sub-optimal therapy• Long duration of HAART• Poor adherence
RNA
RNAD
NA
R-T EnzymeR-T Enzyme
Tests of HIV drug resistance
• Genotypic Assays– Benefits: cheaper, quicker, may detect the
emergence of resistance earlier.– Draw backs: Predictive, not demonstrative
• Phenotypic Assays– Benefits: Useful in highly HAART-experienced
patients needing salvage, may be able to semi-quantitate resistance
– Drawbacks: Long turn-around, expensive
Roles of HIV-Resistance Testing
• Assessment of susceptibility prior to changing HAART;– Starting therapy in a previously treated patient– Changing successful therapy (PCR > 1-2,000)– Changing a failing regimen
• ? Use in choosing an initial HAART regimen in treatment naïve patients
• ? Use in choosing PEP
Reasons for Interruption of HAART
• Patient Fatigue, lack of confidence in rx., fear of toxicity, travel
• Surgical or medical conditions requiring npo
• A failing regimen, while resistance studies are pending
• Poor adherence and need for further patient education
Strategic/Structured Treatment Interruption
(STI)- Rationale
• ? Enhanced HIV-specific cellular and humoral immune response?
• ? Reduction of long term toxicity?
Possible Effects of HAART-induced long-term survival
• Neurological (e.g.- neuropathy, dementia, neuromuscular)
• Neoplastic • Skeletal/ Joint• Cardiovascular (e.g.- ASHD, ASPVD,
cardiomyopathy)• Endocrinologic (e.g.- thyroid, hypothalamic,
adrenal)
New Directions in HAART
• “User Friendly” drugs- (e.g.- QD/ BID, reduced toxicity, fewer drug-drug interactions)
• Optimize pharmacodynamics of existing drugs• Develop NRTI, NNRTI, PI’s with improved
resistance pattern• New Classes of drugs (e.g.- Fusion inhibitors,
Chemokine antagonists, integrase inhibitors, TAT protein and CD-4 antagonists, vaccines, immunostimulants)
Selected HIV agents in development
• Nucleosides- DAPD, Tenofovir, Emtricitabine(FTC), DOTC, GW-42086, D-D4FC
• Non-nucleosides- DPC 961, DPC 083, Capravirine, Calanolide A, TMC 120
• PI’s- Tipranavir, BMS 232632, AG 1776, DMP 450, CGP61755, DPC 681, DPC 684, TMC 126
Selected HIV agents in development-con’t
• Fusion Inhibitors- T-20, T- 1249
• Interleukin-2
• Vaccine development- vCP1452, gp-160
• Integrase Inhibitors- DCQA/DCTA, Zintevir
• Hydroxyurea-like Compds- BCX-34, mycophenolate mofetil
For more HIV-related resources, please visit www.hivguidelines.org
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