therapeutic vaccine for hiv

Conditions: HIV; Therapeutic Vaccine

Summary: background: - in most people who have human immunodeficiency virus (hiv), the immune system cannot control or cure the infection. antiretroviral therapy drugs can keep the amount of hiv virus low for a long time. however, this treatment does not remove the virus from the body. in the vast majority of patients antiretroviral therapy also will not protect the body from the virus once treatment stops. researchers want to see if therapeutic vaccination can help people with hiv. therapeutic vaccination means giving vaccines to treat an infection that someone already has (hiv, in this case). it may help the body's immune system attack the infection. this study will look at different measures of hiv infection after receiving either therapeutic vaccination or a placebo. objectives: - to see whether therapeutic vaccination is safe and can affect how the body responds to hiv infection. eligibility: - individuals between 18 and 65 years of age who have hiv and are taking antiretroviral therapy drugs. design: * participants will be screened with a physical exam and medical history. blood and urine samples will be collected. * during the screening visit and throughout the study until week 56, participants will continue to take their hiv medications. * participants will be divided into two groups. one group will have the study vaccines. the other will have a placebo. * the first study vaccine or placebo will be given in weeks 4, 12, and 36. the second study vaccine or the placebo will be given in weeks 24 and 48. blood samples and other tests will be given at each visit. * after the study visit at week 56, participants will stop their hiv medications until week 72. from weeks 58 through 72, they will come in every 2 weeks for study visits; each visit will take about 1 hour to complete. these visits will look at the body s response to the vaccines and their hiv viral load. after week 72, participants will re-start their hiv medications. * there will be follow-up study visits from weeks 76 to 96, with blood tests and other studies.

the advent of combination antiretroviral therapy (cart) has dramatically improved the clinical outcome in human immunodeficiency virus (hiv)-infected individuals through sustained reduction in viral replication. however, it has become clear that cart alone cannot eradicate hiv in infected individuals, likely in part due to the persistence of viral reservoirs in peripheral blood and various tissue compartments. consequently, a major thrust of hiv research over the past several years has been to develop therapeutic strategies that can eliminate persistent viral reservoirs and boost host immunity to control viral replication upon discontinuation of cart. therapeutic hiv vaccination is one approach that could potentially achieve these goals through vaccine-induced improvement in hiv-specific immune responses and/or by direct reactivation of hiv-specific cd4+ memory t cells that harbor latent hiv. an effective therapeutic vaccine could augment immunologic control of hiv infection and potentially obviate the need for chronic cart. the current study is an exploratory randomized, 2-arm (1:1), double-blind, placebo-controlled trial evaluating the safety and efficacy of an hiv-1 multiantigen plasmid dna (hiv-mag pdna) vaccine prime in combination with an interleukin-12 plasmid dna (il-12 pdna) adjuvant delivered by in vivo electroporation followed by a recombinant vesicular stomatitis virus vector containing the hiv-1 gag gene (rvsv hiv gag) booster vaccine in subjects on cart who started therapy during acute or early hiv infection. subjects will be randomized to receive placebo or the hiv-mag pdna (3000 g) vaccine prime and il-12 pdna adjuvant (1000 g) at week 0, 4, 12, and 36, and the rvsv hiv gag booster vaccine (1x107 plaque-forming units) at week 24 and 48. the hiv-mag pdna vaccine prime and il-12 pdna adjuvant will be administered as 2 im injections, 1 into each deltoid, with electroporation using the ichor tds device, while the rvsv hiv gag booster vaccine will be administered as 2 conventional im injections, 1 into each deltoid. after the week 56 visit, all subjects will undergo an analytical treatment interruption to determine if the vaccination strategy results in an improved immune control of viral replication, as evidenced by a blunted or absent rebound in hiv plasma viremia. all subjects will be followed through week 96 for safety and efficacy parameters. the study population includes hiv-infected adults who began cart during acute or early infection. subjects must be receiving an effective cart regimen, with a cd4 cell count of \>450 cells/mm3 at screening, and they must have documented viral suppression below the limit of detection for greater than1 year. the rationale for testing the study vaccine regimen in this subject population is because these individuals may have a relatively preserved immune function, which could be augmented by therapeutic vaccination.

Eligibility criteria:
* inclusion criteria: 1. age, 18-65 years. 2. institution of cart within 12 weeks of being diagnosed with acute or early hiv-1 infection. acute hiv-1 infection is defined as: 1. detectable plasma hiv-1 rna levels of greater than 2000 copies/ml with a negative result from an hiv-1 eia, or 2. positive result from an hiv-1 eia with a negative or indeterminate result from an hiv-1 western blot that subsequently evolves to a confirmed positive result, or 3. negative result from an hiv-1 eia within the past 4 months and hiv-1 rna levels of greater than 400,000 copies/ml, in the setting of a potential exposure to hiv-1. early hiv-1 infection is defined as: 1. negative result from an hiv-1 eia within 6 months prior to a positive result from an hiv-1 eia and an hiv-1 western blot. 2. negative result from a rapid hiv-1 test within 1 month prior to a positive result from an hiv-1 eia and an hiv-1 western blot. 3. presence of low level of hiv antibodies as determined by having a positive eia or a positive western blot with a non-reactive detuned eia according to a serologic testing algorithm for recent infection. 3. cd4+ cell count greater than 450 cells/mm3 at screening. 4. documentation of continuous cart treatment with suppression of plasma viral level below the limit of detection for greater than 1 year. subjects with a single blip (i.e., detectable viral levels on cart) prior to randomization may be included provided they satisfy the following criteria: 1. the blips are less than 400 copies/ml, and 2. succeeding viral levels return to levels below the limit of detection on subsequent testing. 5. willingness to undergo ati. 6. laboratory values within pre-defined limits at screening: * absolute neutrophil count greater than 1,000/mm3. * hemoglobin levels greater than 10.0 g/dl for men and greater than 9.0 g/dl for women. * platelet count greater than 100,000/mm3. * prothrombin time (pt) and partial thromboplastin time (ptt) less than 1.5 upper limit of normal (uln). * estimated or a measured creatinine clearance rate of greater than 60 ml/min as determined by the nih clinical center laboratory. * ast and alt levels of less than 2.5 x uln. 7. willingness to have samples stored for future research. 8. women of childbearing potential must have a negative pregnancy test result. * they must agree to use an adequate form of contraception: * hormonal contraception. * male or female condoms with or without a spermicidal * diaphragm or cervical cap with a spermicidal. * intrauterine device. exclusion criteria: 1. allergy to amide-type local anesthetics (bupivacaine (marcaine), lidocaine (xylocaine), mepivacaine (polocaine/carbocaine), etidocaine (duranest), prilocaine (citanest, emla cream). 2. chronic hepatitis b, as evidenced by a positive test for hepatitis b surface antigen (hbsag), or chronic hepatitis c virus (hcv) infection, as evidenced by a positive test for hcv rna. subjects with a positive test for hcv antibody and a negative test for hcv rna are eligible. 3. changes in cart regimen due to virologic breakthrough. 4. hiv immunotherapy or vaccine(s) received within 1 year prior to screening. 5. any licensed or experimental non-hiv vaccination (e.g., hepatitis b, influenza, pneumococcal polysaccharide) received within 4 weeks prior to study entry. 6. interruption of cart for greater than 3 months since its initiation. 8. any active malignancy that may require systemic chemotherapy or radiation therapy. 7. pregnancy or planned pregnancy during the study period or breastfeeding. 8. any active malignancy that may require systemic chemotherapy or radiationtherapy. 9. immunosuppressive medications received within 6 months before the first study vaccination (not excluded: (1) corticosteroid nasal spray for allergic rhinitis; (2) topical corticosteroids for mild, uncomplicated dermatitis; or (3) oral/parenteral corticosteroids administered for non-chronic conditions not expected to recur (length of therapy less than or equal to10 days, with completion in greater than or equal to 30 days prior to enrollment). 10. evidence of hepatic decompensation in subjects with cirrhosis: history of ascites, hepatic encephalopathy, or bleeding esophageal varices, or screening laboratory results with any of the following: 1. international normalized ratio of greater than or equal to1.5 x uln. 2. serum albumin less than 3.2 g/dl. 3. serum total bilirubin greater than 1.8 x uln, unless history of gilbert's disease or deemed related to treatment with atazanavir. 11. history or other clinical evidence of: 1. significant or unstable cardiac disease (e.g., angina, congestive heart failure, recent myocardial infarction, significant arrhythmia). 2. severe illness, malignancy, immunodeficiency other than hiv, or any other conditions that, in the opinion of the investigator, would make the subject unsuitable for the study. 3. aids-defining condition. 12. known allergy or sensitivity to the components of the investigational therapy. 13. history of significant cardiac arrhythmia (e.g., supraventricular tachycardia, ventricular tachycardia, and atrial fibrillation/flutter). 14. active drug or alcohol use or any dependence other pattern of behaivor that, in the opinion of the investigator, would interfere with adherence to study requirements. 15. any active systemic inflammatory or autoimmune disease or condition. 16. presence of implanted electronic medical device (e.g., pacemaker, implantable cardiac defibrillator) or surgical/traumatic metal implant in the upper limb and/or upper torso. 17. neurological or neuropsychiatric disorder that may interfere with the assessment of safety (e.g., frequent recurring headaches, for example, a pattern of greater than 1 headache/month affecting activities of daily living/work, frequent or severe/complicated migraines, cluster headaches); or history of encephalitis, narcolepsy, stroke with sequelae, moderate/severe major depressive disorder, moderate/severe bipolar disorder, seizure disorder. 18. deltoid skinfold measurements (by caliper) of greater than 40 mm. 19. body mass index greater than 40.

Keywords: hiv-mag pdna prime hiv therapy therapeutic vaccine