Retrospective analysis of suspending HAART in selected patients with controlled HIV replication

We sought to determine the consequences of stopping highly active antiretroviral therapy (HAART) in a group of 41 HIV-infected individuals with undetectable HIV viral loads and CD4+ counts greater than 500 cells per microliter for 6 months or more. Clinical and laboratory parameters were monitored, as was the time to HAART reinitiation. Three months after HAART interruption, the median CD4+ count declined by 162 cells per microliter and HIV viral load increased by 24,000 copies per milliliter. Over the next year, CD4+ counts continued to decrease by an average of 11 cells per microliter per 3-month intervals. In contrast, HIV viral loads remained stable over the same period. Five of 7 patients (71%) with elevated cholesterol levels and 6 of 13 patients (46%) with elevated triglyceride levels had these values normalize after stopping HAART. After a median of 21 months follow-up, 26 of 41 patients (63%) have restarted HAART. Patients with Centers for Disease Control (CDC) HIV/AIDS C classification were more likely to restart HAART than those with A or B classification (p = 0.008). Reasons for HAART restart included clinical events in 8 patients. Fifteen patients restarted HAART for immunologic reasons: CD4+ count less than 300 cells per microliter (n = 7); HIV viral load greater than 55,000 copies per milliliter (n = 3); or both (n = 5). Three patients restarted HAART because of personal preference. Within 4 months, all 26 patients who restarted HAART achieved HIV viral loads less than 50 copies per milliliter. Although patients were able to rapidly achieve nondetectable HIV viral loads after restarting HAART, the inability to foresee clinical events among 8 patients (20%) is disconcerting. We advise caution before HAART interruption, particularly for those patients with a preceding history of significant HIV-related complications.     

CD4 cell-monitored treatment interruption in patients with a CD4 cell count > 500 x 106 cells/l

BACKGROUND: Little is known about CD4 cell count changes in patients with high CD4 cell counts who interrupt antiretroviral therapy, especially in those with a nadir of 250-350 x 10 cells/l. METHODS: Data derived from 139 patients from seven prospective cohorts who had > 12 months highly active antiretroviral therapy (HAART), CD4 cell count nadir of > 250 x 10 cells/l and at pre-interruption of > 500 x 10 cells/l. Endpoint was time to CD4 cell count < 350 x 10 cells/l or reinitiation of treatment. RESULTS: At interruption, the median CD4 cell count was 800 x 10 cells/l, median viral load was 1.7 log10 copies/ml. At the time of analysis, 63 (45.3%) had resumed therapy or experienced < 350 x 10 cells/l CD4 cells over a median interruption of 75 weeks. Of these, 33 (52.4%) experienced a decline to < 350 x 10 cells/l and 30 (47.6%) restarted therapy before their CD4 cell count had fallen below this level. In 43 patients with CD4 cell nadir of 251-350 x 10 cells/l, median time to therapy resumption or CD4 cell count < 350 x 10 cells/l was 61 weeks. Higher CD4 cell count nadir, longer duration of viral load suppression on therapy, and higher viral load level at interruption were independently associated with longer time to restart therapy. The risk of clinical events was 5 per 1000 person-years of follow-up. CONCLUSIONS: Patients who started therapy with CD4 cell count of 250-350 x 10 cells/l and who later interrupted therapy appear able to remain off therapy with a CD4 cell count > 350 x 10 cells/l for a substantial period of time.     

The virological and immunological consequences of structured treatment interruptions in chronic HIV-1 infection.

BACKGROUND: Some individuals with chronic HIV-1 infection have discontinued their drug therapy with consequent plasma virus rebound. In a small number of patients, a delayed or absent rebound in plasma virus load has been noted after drug cessation, apparently associated with prior drug interruptions and autologous boosting of HIV-1 specific immune responses. We hypothesized that cyclic structured treatment interruptions structured treatment interruptions (STI) could augment HIV-1 specific immune responses in chronic HIV-1 infection, which might help to control HIV-1 replication off therapy. METHODS: We initiated an STI pilot study in 10 antiretroviral treatment-naive HIV-1 chronically infected subjects with baseline CD4 T-cell counts > 500 x 10(6) cells/l and plasma viral load > 5000 copies/ml who received highly active antiretroviral therapy (HAART) for 1 year with good response (plasma viral load < 20 copies/ml for at least 32 weeks). Three cycles of HAART interruption were performed. RESULTS: In all of the patients viral load rebounded, but doubling times increased significantly between the first and third stops (P = 0.008), and by the third stop, six out of nine subjects had a virological set-point after a median 12 months off therapy that was lower than baseline before starting HAART (ranging from 0.6 log(10) to 1.3 log(10) lower than baseline) and in four it remained stable below 5000 copies/ml. Those subjects who controlled viral replication developed significantly stronger HIV-1 specific cellular immune responses than subjects lacking spontaneous decline (P < 0.05). During viral rebounds no genotypic or phenotypic changes conferring resistance to reverse trancriptase inhibitors or protease inhibitors was detected, but mean absolute CD4 T-cell counts declined significantly, although never below 450 x 10(6)/l and the mean value at 12 months off therapy was significantly higher than the pre-treatment level (P = 0.004). CONCLUSIONS: Our findings suggest that STI in chronic HIV-1 infection might augment HIV-1-specific cellular immune responses associated with a spontaneous and sustained drop in plasma viral load in some subjects but at the potential cost of lower CD4 T-cell counts.     

Structured intermittent interruption of chronic HIV infection treatment with highly active antiretroviral therapy: effects on leptin and TNF-alpha

The changes in nutritional parameters and adipocytokines after structured intermittent interruption of highly active antiretroviral treatment of patients with chronic HIV infection are analyzed. Twenty-seven patients with chronic HIV infection (median CD4+ T cell count/microl: nadir, 394; at the beginning of structured interruptions, 1041; HIV viral load: nadir, 41,521 copies/ml; at the beginning of structured interruptions <50 copies/ml; median time of previous treatment: 60 months) were evaluated during three cycles of intermittent interruptions of therapy (8 weeks on/4 weeks off). CD4+ T cell count, HIV viral load, anthropometric measures, and serum concentrations of triglycerides, cholesterol, leptin, and tumor necrosis factor and its soluble receptors I and II were determined. After the three cycles of intermittent interruptions of therapy, no significant differences in CD4+ T cell count/microl, viral load, or serum concentrations of cholesterol or triglycerides with reference to baseline values were found. A near-significant higher fatty mass (skinfold thicknesses, at the end, 121 mm, at the beginning, 100 mm, p = 0.100), combined with a significant increase of concentration of leptin (1.5 vs. 4.7 ng/ml, p = 0,044), as well as a decrease in serum concentrations of soluble receptors of tumor necrosis factor (TNFRI, 104 vs. 73 pg/ml, p = 0.022; TNFRII 253 vs. 195 pg/ml, p = 0.098) were detected. Structured intermittent interruption of highly active antiretroviral treatment of patients with chronic HIV infection induces a valuable positive modification in markers of lipid turnover and adipose tissue mass.     

CD4+ cell-count-guided treatment interruptions in chronic HIV-infected patients with good response to highly active antiretroviral therapy

OBJECTIVE: To evaluate the safety of treatment interruption guided by CD4+ cell count in HIV-infected patients followed up prospectively. METHODS: Patients on highly active antiretroviral therapy with CD4+ cell counts > 500 x 10(6) cells/l discontinued therapy with instructions to start therapy again before their CD4+ count dropped below 200 x 10(6) cells/l. Any patients who resumed therapy would be eligible to interrupt treatment again once their CD4+ cell count increased above 500 x 10(6) cells/l. RESULTS: Data on 71 HIV infected patients is reported. Their median nadir CD4+ cell count before antiretroviral treatment was 352 x 10(6) cells/l [interquartile range (IQR), 294-445 x 10(6) cells/l]. The median CD4+ cell count at the time of first interruption was 790 x 10(6) cells/l (IQR, 657-1041 x 10(6) cells/l). The median follow-up after starting the first treatment interruption was 28.3 months (IQR, 21.4-37.0 months). During the follow-up 49 patients restarted therapy and 22 patients remain off therapy; 24 patients have interrupted therapy twice, nine patients have interrupted therapy three times and six patients four times. No AIDS-defining illnesses occurred during the follow-up. The median duration of the first interruption was 15 months (IQR, 6-26 months). The overall reduction of time on therapy was 71.1%. The duration of the first interruption and the reduction of time on therapy were related to nadir CD4+ cell count. The patients who resumed HAART rapidly regained CD4+ cells and achieved viral suppression. CONCLUSION: If carefully monitored, treatment interruptions guided by CD4+ cell count in patients with an initially high CD4+ cell counts are clinically safe, decrease exposure to the drugs and do not reduce the efficacy of therapy when this is re-started.     

Immunological markers after long-term treatment interruption in chronically HIV-1 infected patients with CD4 cell count above 400 x 10(6) cells/l

OBJECTIVE: To analyse immunological markers associated with CD4+ lymphocyte T-cell count (CD4+) evolution during 12-month follow-up after treatment discontinuation. METHOD: Prospective observational study of chronically HIV-1 infected patients with CD4+ above 400 x 10(6) cells/l. RESULTS: CD4+ changes took place in two phases: an initial rapid decrease in the first month (-142 x 10(6) cells/l on average), followed by a slow decline (-17 x 10(6) cells/l on average) The second slope of CD4+ decline was not correlated with the first and only baseline plasma HIV RNA was associated with it. The decline in CD4+ during the first month was steeper in patients with higher CD4+ and weaker plasma HIV RNA baseline levels. Moreover, the decline was less pronounced (P < 10(-4)) in patients with CD4+ nadir above 350 x 10(6) cells/l (-65 x 10(6) cells/l per month) in comparison with those below 350 x 10(6) cells/l (-200 x 10(6) cells/l per month). A high number of dendritic cells (DCs) whatever the type was associated with high CD4+ at the time of treatment interruption and its steeper decline over the first month. Moreover, the myeloid DC level was stable whereas the lymphoid DC count, which tended to decrease in association with decrease in CD4+, was negatively correlated with the HIV RNA load slope. CONCLUSIONS: The results support the use of the CD4+ nadir to predict the CD4+ dynamic after treatment interruption and consideration of the CD4+ count after 1-month of interruption merely reflects the 12-month level of CD4+. Although DCs seem to be associated with the CD4+ dynamic, the benefit of monitoring them has still to be defined.     

Immunophenotype of HIV+ patients during CD4 cell-monitored treatment interruption: role of the IL-7/IL-7 receptor system

OBJECTIVE: To investigate immunological changes during CD4-guided therapy interruption in HIV(+) patients who suspended HAART. PATIENTS: Seventeen patients aged > 18 years, who had received HAART for at least 12 months, and had a pre-interruption CD4+ cell count > 500 cells/microl, interrupted treatment. Median nadir CD4(+) cell count was 288 cells/microl. HIV plasma viral load at discontinuation was < 50 or > 50 copies/ml. Criteria for restarting treatment were: a CD4(+) T-lymphocyte count < 350 cells/microl on two separate occasions, a clinical manifestation of AIDS, and the patient's desire to resume HAART. Eleven patients were still off therapy after 12 months (group A); according to the first criterion, six patients restarted therapy within 12 months (group B). METHODS: Haematological, viro-immunological, cytofluorimetic and molecular assays were performed at baseline and every 2 months following standard methods. Statistical analysis was performed under Stata 7.0. RESULTS: In the first 2 months of treatment interruption, a significant increase in viral load and CD8(+) lymphocyte activation occurred. Then such parameters decreased and remained stable. In all patients, a decrease in CD4(+) lymphocytes took place as well, that affected in a similar manner naive, central memory, effector memory and terminally differentiated cells. Group B always presented lower amounts of CD4(+) effector memory lymphocytes. The expression of CD127 was always higher in group A. CONCLUSIONS: The loss of CD4(+) lymphocytes upon viral rebound is equal among naive and memory subsets. Patients with higher expression of CD127, who are likely to exert a better capacity to utilize endogenous interleukin-7 by T cells, could remain off therapy for longer periods.     

Recrudescent Kaposi's sarcoma after initiation of HAART: a manifestation of immune reconstitution syndrome

The objective of this case series and literature review is to characterize the clinical course and prognosis of HIV-infected patients with Kaposi's sarcoma (KS) flare during immune reconstitution inflammatory syndrome (IRIS), a heterogeneous and sometimes fatal disorder of immune perturbation after initiation of highly active antiretroviral therapy (HAART). Medical records of 9 HIV-infected patients with KS flare after virologic and immunologic response to HAART were reviewed from a single institution. An additional 10 cases were abstracted by computerized search of the medical literature. In our single institution series, mean time to onset of KS flare was 5 weeks. Pretreatment mean CD4+ count was 190 cells/mm(3) and mean HIV viral load was 153,934 copies per milliliter. During flare, mean CD4+ count was 256 cells/mm(3) and mean HIV viral load was 1156 copies per milliliter. Similar aggregate results are represented in the literature. Six fatalities are reported, 4 from pulmonary KS and 2 from unrelated causes. Systemic chemotherapy universally led to tumor regression, but was administered in only 10 of 19 cases. In no instance was HAART discontinued. Onset of IRIS-associated KS flare is observed as early as 3 weeks, with most cases diagnosed within 2 months after immunologic and virologic response to HAART. Such a flare does not necessarily portend a poor prognosis. Even for those patients with rapidly symptomatic KS, early systemic chemotherapy is effective in suppressing IRIS-associated flare. Close clinical supervision is warranted for the KS patient initiating, changing, or resuming HAART. Particular vigilance is recommended for pulmonary involvement.     

Nadir CD4+ T-cell count and numbers of CD28+ CD4+ T-cells predict functional responses to immunizations in chronic HIV-1 infection

OBJECTIVE: To ascertain whether delaying the initiation of highly active antiretroviral therapy (HAART) compromises functional immune reconstitution in HIV-1 infection in persons who regain 'normal' CD4 T-cell counts after suppressive antiretroviral therapies. DESIGN: Prospective open-label study carried out at two University-affiliated HIV-outpatient clinics in the USA. SUBJECTS AND METHODS: Response to immunization was used as a model for in vivo functional immune competence in 29 HIV-1 infected patients with CD4 T-cell counts > 450 x 106 cells/l and HIV-RNA < 400 copies/ml for > 12 months after HAART and nine HIV-1 seronegative controls. After immunization with tetanus toxoid, diphtheria-toxoid, and keyhole limpet hemocyanin, immune response scores (IRS) were calculated using postimmunization antibody concentrations, lymphocyte proliferation, and delayed-type hypersensitivity responses to vaccine antigens. RESULTS: Despite normal numbers of circulating CD4 T-cells, the CD4 T-cell nadir before HAART initiation predicted the immune response to immunization (rho = 0.5; P < 0.005) while current CD4 T-cell count did not. Likewise, CD4 T-lymphocyte expression of the co-stimulatory molecule CD28 was also an independent predictor of response to immunization (rho = 0.5; P < 0.005). CONCLUSIONS: Even among persons who controlled HIV replication and normalized CD4 T-cell counts with HAART, pretreatment CD4 T-cell count and numbers of circulating CD4+CD28+ T-cells at immunization, but not current CD4 T-cell count, predict the ability to respond to vaccination. Delaying the initiation of HAART in chronic HIV-1 infection results in impaired functional immune restoration despite normalization of circulating CD4 T-cell numbers.     

Highly active antiretroviral therapy as the sole treatment for AIDS-related primary central nervous system lymphoma: a case report with implications for treatment

A 40-year-old male presented to medical attention with Pneumocystis jiroveci pneumonia and HIV infection. His CD4+ count was 18 cells per microliter and his HIV viral load (VL) was more than 400,000 copies milliliter. After 3 weeks of antibiotic therapy, he continued to have global cognitive deficits. A brain imaging study showed a right temporal mass, which on biopsy proved to be primary central nervous system lymphoma (PCNSL). He began highly active antiretroviral therapy (HAART) but declined palliative whole-brain radiotherapy (WBRT). Four months later, his CD4+ count had improved to 153 cells per microliter and his HIV VL was less than 75 copies per milliliter. At 36 months follow-up, he remained in complete remission (CR). Through a literature review, we identified 4 additional PCNSL patients who achieved prolonged remission after the initiation of HAART. One patient required WBRT and ventriculo-peritoneal shunting for signs and symptoms of obstructive hydrocephalus. The other 3 patients presented with stable neurologic findings and were treated with HAART alone. The median initial CD4+ count for these patients was 50 cells per microliter (range, 2 to 220 cells per microliter). All 5 remained in CR with a median follow-up of 23.5 (range, 13 to 36) months. For patients who present with PCNSL as their initial AIDS-defining event, stable neurologic findings, and effective HAART options, initial treatment with HAART alone may be possible, reserving WBRT and corticosteroids for those who show signs of impending neurologic demise. Chemotherapy and other novel approaches could also be considered for selected patients with lesser degrees of immune suppression and high baseline functional status.     

Immunologic and virologic consequences of temporary antiretroviral treatment interruption in clinical practice

To determine the long-term immunologic and virologic effects of antiretroviral treatment interruptions, a retrospective analysis of an ongoing observational database was performed at a university HIV clinic. All patients who began highly active antiretroviral therapy (HAART) after January 1, 1996 and (1) were HAART experienced for >/=90 days, (2) had a treatment interruption (TI) for >/=30 days, (3) resumed HAART for >/=30 days, and (4) had CD4(+) cell counts performed pre- and post-TI were included. Main outcome measures included the following: Immunologic success was defined as a post-TI CD4(+) cell count >90% of the pre-TI CD4(+) cell count (post-TI/pre-TI, >90%). Virologic success was defined as a post-TI viral load (VL) less or equal to twice the pre-TI VL (post-TI/pre-TI, 相似文献   

Five-year immunological outcome of highly active antiretroviral treatment in a clinical setting: results from a single HIV treatment centre

Our objective was to study the evolution of CD4 cell count five years after starting highly active antiretroviral treatment (HAART) in a clinical setting. The study was performed at the HIV outpatient clinic, Institute of Tropical Medicine, Antwerp. All patients (n = 225) who started HAART in 1997, who had a CD4 cell count within six months prior to starting HAART and who were subsequently followed for at least two years were included. Change in CD4 cell count after start of HAART and the influence of patient and clinical factors were investigated using graphical exploration, endpoint analysis and mixed-effects linear regression. The mean CD4 cell count at start of HAART was 280 cells/mm(3). At the five-year endpoint of the study the mean increase in CD4 cell count was 333 cells/mm(3), while 79% of the patients had a viral load less than 400 copies/mL. There was a significant negative correlation between increase in CD4 cell count at five years and time since first positive HIV test at start of HAART (P = 0.021). Patients who ever had a HAART interruption of more than seven days had a significantly lower increase in CD4 cell count than those who did not (225 cells/mm(3) compared with 438 cells/mm(3); P < 0.001). A mixed-effects linear regression model additionally suggested a significant impact of exposure to antiretrovirals prior to HAART (P = 0.03). Overall, the recovery of CD4 cell count after five years of HAART is good, although therapy interruptions have an important negative impact.     

A prospective trial of structured treatment interruptions in human immunodeficiency virus infection

BACKGROUND: According to the "autovaccination hypothesis," reexposure to human immunodeficiency virus (HIV) during treatment interruptions may stimulate the HIV-specific immune response and lead to low viremia after withdrawal of highly active antiretroviral treatment (HAART). Many patients who started HAART earlier in their disease course than is currently recommended would like to discontinue, but it is unknown whether it is safe to do so. OBJECTIVES: To determine whether repeated treatment interruptions of HAART (1) stimulated the cytotoxic HIV-specific immune response and whether such stimulation correlated with low viremia off treatment, and (2) were safe with respect to clinical complications, development of viral resistance, and decline in CD4 cell counts. DESIGN: Interventional study with before-after comparison. SETTING: Outpatient clinics of university hospitals in Switzerland and Spain. PATIENTS: A total of 133 patients receiving HAART, with a median CD4 cell count of 740/ microL, and whose viral load had been undetectable for a median of 21 months. INTERVENTIONS: HAART was interrupted for 2 weeks, restarted, and continued for 8 weeks. After 4 such cycles, treatment was indefinitely suspended 40 weeks after study entry. MAIN OUTCOME MEASURES: HIV-specific cytotoxic T-cell responses were evaluated by interferon gamma enzyme-linked immunospot analysis. The proportion of "responders" (viral load <5000 copies/mL) was measured at weeks 52 and 96. HIV-related diseases and CD4 cell counts were recorded. RESULTS: Seventeen percent of patients (95% confidence interval, 11%-25%) were responders at week 52, and 8% at week 96. Low pre-HAART viral load and lack of rebound during weeks 0 to 40 predicted response. HIV-specific CD8+ T cells increased between week 0 (median, 343 spot-forming cells per million peripheral blood lymphocytes [SFC/106 PBL]) and week 52 (median, 1930 SFC/106 PBL), but there was an inverse correlation between response and the number of spot-forming cells. Eighty-five (64%) of 133 patients stopped therapy for at least 12 weeks, and 55 (41%) for at least 56 weeks. The median CD4 cell count decreased from 792/ microL to 615/ microL during the first 12 weeks without treatment, but stabilized thereafter. One patient (0.75%) developed drug resistance necessitating salvage treatment. There were no AIDS-related clinical complications. CONCLUSIONS: Results of this study do not favor the autovaccination hypothesis. Treatment interruptions did not provoke clinical complications, and there was little drug resistance. Comparative trials will have to show what benefit, if any, is associated with intermittent, as opposed to continuous treatment.     

Development of opportunistic infections after diagnosis of active tuberculosis in HIV-infected patients

Despite advances in highly active antiretroviral therapy (HAART), its use during tuberculosis (TB) treatment is fraught with challenges, often leading to delayed therapy. This report describes the course of HIV infection and outcomes of 26 consecutive TB/HIV coinfected patients who received TB treatment in Rhode Island. HIV infection was diagnosed in 26 (4%) of 598 TB cases in during a 10-year period. Of these patients, TB was the first indication of HIV infection in 15 patients (58%). Of the 21 patients who were not on antiretrovirals at the time of TB diagnosis, 17 (81%) met criteria for immediate initiation of HAART. The median CD4 cell counts and HIV-1 plasma viral load were 80 cells per microliter (range, 2-800 cells per microliter) and 255,631 copies per milliliter (range, 50,000 to > 500,000 copies per milliliter), respectively, for the patients whose baseline measurements were available. CD4 lymphocyte count was less than 200 cells per microliter in 13 (76%) of the 17 patients whose measurements were available. Three (30%) of the 10 patients whose CD4 cell count was less than 100 cells per microliter developed subsequent AIDS-defining illness prior to the initiation of HAART and a fourth patient, within 30 days of starting HAART. None of the patients who had CD4 cell counts 100 cells per microliter or greater developed subsequent AIDS-defining illness during TB treatment. The median time to starting HAART after starting TB treatment was 12 weeks (range, 3-36 weeks). From our limited experience based on this case series, we recommend early initiation of HAART in coinfected patients with CD4 cell counts less than 100 cells per microliter.     

Safety of long-term interruption of successful antiretroviral therapy: the ATHENA cohort study

We studied the dynamics of CD4 cell counts after the interruption of virologically successful highly active antiretroviral therapy (HAART) in 139 patients. Changes in CD4 cell counts during HAART interruption followed a biphasic pattern: an initial rapid decline during the first month followed by a slow decrease. During 48 weeks of follow-up mean CD4 cell counts remained just above the mean pre-HAART level. This limits the feasibility of structured treatment interruptions for patients with low nadir CD4 cell counts.     

Treatment interruption of highly active antiretroviral therapy in patients with nadir CD4 cell counts >200 cells/mm3

BACKGROUND: The goal of the present study was to characterize outcome and predictors of outcome of treatment interruption (TI) in highly active antiretroviral therapy (HAART)-treated patients. METHODS: A systematic chart/database review was conducted to identify patients with nadir CD4 cell counts >200 cells/mm(3) and without acquired immunodeficiency syndrome-defining illnesses who underwent a TI. Collected data included duration and reason for TI, demographic characteristics, CD4 cell count, and plasma viral load. Human immunodeficiency virus (HIV) envelope (V3) loop genotyping was performed on plasma HIV RNA. The presence of basic residues at aa 11 and/or 25 (the "11/25" genotype) was a further possible prognostic variable of interest. Cox proportional hazards models were used to assess characteristics associated with time to HAART reinitiation after TI. RESULTS: A total of 208 of 4461 (4.7%) patients underwent TI. The study group consisted of 197 (94.7%) of 208 participants for whom V3 genotyping was successful. The median CD4 cell count at time of the initiation of TI was 620 cells/mm(3). A total of 59 (29.9%) patients reinitiated HAART after a median of 15 months. At the time of the reinitiation of HAART, the median plasma viral load was >100,000 copies/mL, and the median CD4 cell count was 260 cells/mm(3). Among the 197 study patients, there were 6 deaths, none of which was attributable to the TI. A total of 81% had plasma viral loads <50 copies/mL by 15 months of follow-up after reinitiation of HAART. In multivariate analysis, a nadir CD4 cell count < or =250 cells/mm(3) (risk ratio [RR], 2.79 [95% confidence interval [CI], 1.60-4.86]; P < .001) and the presence of the 11/25 genotype (RR, 2.07 [95% CI, 1.07-4.02]; P = .031) were positively and independently associated with faster time to HAART reinitiation, after adjusting for age and plasma virus load at the start of TI. CONCLUSIONS: Our study suggests that TI is a viable option for HIV-positive adults with nadir CD4 cell counts >250 cells/mm(3). A nadir CD4 cell count of 200-250 cells/mm(3) and the 11/25 viral genotype were found to be associated with a faster HAART reinitiation.     

Rapid activation of lymph nodes and mononuclear cell HIV expression upon interrupting highly active antiretroviral therapy in patients after prolonged viral suppression

OBJECTIVE: To compare the architecture and HIV-1 RNA and Gag p24 protein expression in lymph nodes (LN) excised from individuals during chronic highly active antiretroviral therapy (HAART) with LN removed from the same patient after plasma virus rebound following the interruption of HAART. MATERIALS AND METHODS: Six HIV-1-infected patients on HAART, with CD4 cell counts greater than 350 cells/microl, and plasma HIV-1 RNA less than 50 copies/ml, underwent inguinal LN excision upon discontinuation of HAART, and again after rebound of plasma virus. Lymph nodes were evaluated by immunohistochemical staining for Gag p24 antigen and Ki67, in-situ hybridization for HIV-1 RNA and H3-histone, and transmission electron microscopy (TEM). RESULTS: LN at baseline were quiescent to mildly hyperplastic and generally contained more primary than secondary follicles. Only one LN had detectable follicular dendritic cell (FDC)-associated p24 antigen, none had HIV RNA. Few mononuclear cells (MNC) expressed RNA or p24 antigen. Plasma virus at the second biopsy ranged from 329 to 3.2 x 10(6) copies/ml. CD4 cell count decline ranged from 5 to 51% during drug hiatus, and was greatest in patients with highest viral rebound. Four of six of the second LN were more hyperplastic than the initial LN, two showed paracortical hyperplasia. MNC expression of HIV RNA in the second LN paralleled the level of plasma viremia. Increased Ki67 and H3-histone signal occurred in the second LN. CONCLUSION: Quiescent LN from individuals on HAART rapidly become hyperplastic and activated within 1-2 months after treatment interruption. As in acute HIV infection, virus expression by LN MNC parallels the rebound in plasma viremia and fall in CD4 cell count.     

HIV-1 and T cell dynamics after interruption of highly active antiretroviral therapy (HAART) in patients with a history of sustained viral suppression

Identifying the immunologic and virologic consequences of discontinuing antiretroviral therapy in HIV-infected patients is of major importance in developing long-term treatment strategies for patients with HIV-1 infection. We designed a trial to characterize these parameters after interruption of highly active antiretroviral therapy (HAART) in patients who had maintained prolonged viral suppression on antiretroviral drugs. Eighteen patients with CD4(+) T cell counts >/= 350 cells/microliter and viral load below the limits of detection for >/=1 year while on HAART were enrolled prospectively in a trial in which HAART was discontinued. Twelve of these patients had received prior IL-2 therapy and had low frequencies of resting, latently infected CD4 cells. Viral load relapse to >50 copies/ml occurred in all 18 patients independent of prior IL-2 treatment, beginning most commonly during weeks 2-3 after cessation of HAART. The mean relapse rate constant was 0.45 (0.20 log(10) copies) day(-1), which was very similar to the mean viral clearance rate constant after drug resumption of 0.35 (0.15 log(10) copies) day(-1) (P = 0.28). One patient experienced a relapse delay to week 7. All patients except one experienced a relapse burden to >5,000 RNA copies/ml. Ex vivo labeling with BrdUrd showed that CD4 and CD8 cell turnover increased after withdrawal of HAART and correlated with viral load whereas lymphocyte turnover decreased after reinitiation of drug treatment. Virologic relapse occurs rapidly in patients who discontinue suppressive drug therapy, even in patients with a markedly diminished pool of resting, latently infected CD4(+) T cells.     

Factors associated with poor immunologic response to virologic suppression by highly active antiretroviral therapy in HIV-infected women

Virologic response to highly active antiretroviral therapy (HAART) typically results in a substantial rise in CD4 cell counts. We investigated factors associated with poor CD4 response among HIV-infected women followed at 6-monthly intervals in the Women's Interagency HIV Study. Women with nadir CD4 counts < 350 cells/mm3 who achieved at least 6 months of plasma HIV RNA < 400 copies/ml were studied. Demographic, clinical, and treatment factors were compared between immunologic nonresponders, defined as the lower quartile of CD4 count change after two visits with virologic suppression (< 56 cell/mm3; n = 38), and the remaining group of responders (n = 115). Immunologic nonresponders had lower baseline HIV RNA levels and higher CD4 counts, more frequently used HAART 6 months prior to achieving consistent viral suppression, and more commonly had HIV RNA levels > 80 but < 400 copies/mL at both suppressive visits (21 vs. 7.8%, p = 0.024). In multivariate analysis, higher CD4 count and lower HIV RNA level at the last presuppressive visit were associated with immune nonresponse. We conclude that higher baseline CD4 count and lower HIV RNA level were associated with poor immunologic response to HAART in women with virologic suppression for at least 6 months. Persistent low level viremia may also contribute.