Safe Treatment Interruptions in Patients With Nadir CD4 Counts of More Than 350 Cells/μL

Clinical trials of antiretroviral treatment interruption in HIV-infected individuals

: Despite the benefits of antiretroviral therapy (ART) for people living with HIV, there has been a long-standing research interest in interrupting ART as a strategy to minimize adverse effects of ART as well as to test interventions aiming to achieve a degree of virological control without ART. We performed a systematic review of HIV clinical studies involving treatment interruption from 2000 to 2017 to describe the differences between treatment interruption in studies that contained and didn't contain an intervention. We assessed differences in monitoring strategies, threshold to restart ART, duration and adverse outcomes of treatment interruption, and factors aimed at minimizing transmission. We found that treatment interruption has been incorporated into 159 clinical studies since 2000 and is increasingly being included in trials to assess the efficacy of interventions to achieve sustained virological remission off ART. Great heterogeneity was noted in immunological, virological and clinical monitoring strategies, as well as in thresholds to recommence ART. Treatment interruption in recent intervention studies were more closely monitored, had more conservative thresholds to restart ART and had a shorter treatment interruption duration, compared with older treatment interruption studies that didn't include an intervention.

Immunological analysis of treatment interruption after early highly active antiretroviral therapy

We longitudinally evaluated HIV-specific T-cell immunity after discontinuation of highly active antiretroviral therapy (HAART). After treatment interruption (TI), some individuals could maintain a low plasma viral load (<15,000 copies/mL), whereas others could not (>50,000 copies/mL). Before HAART was initiated, plasma viral load was similar. After TI, the numbers of CD8(+) T cells increased more in individuals without viral control, whereas individuals maintaining a low viral load showed a more pronounced increase in HIV-specific CD8(+) T-cell numbers. No differences were seen in the number or percentage of cytokine-producing HIV-1-specific CD4(+) T cells, or in proliferative capacity of T cells. Four weeks after TI, the magnitude of the total HIV-1-specific CD8(+) T-cell response (IFN-γ(+) and/or IL-2(+) and/or CD107a(+)) was significantly higher in individuals maintaining viral control. Degranulation contributed more to the overall CD8(+) T-cell response than cytokine production. Whether increased T-cell functionality is a cause or consequence of low viral load remains to be elucidated.

Postpartum discontinuation of antiretroviral therapy and risk of maternal AIDS-defining events, non-AIDS-defining events, and mortality among a cohort of HIV-1-infected women in the United States

This retrospective cohort study of HIV-infected women receiving highly active antiretroviral therapy (HAART) while pregnant assessed the effect of postpartum HAART discontinuation on maternal AIDS-defining events (ADEs), non-AIDS-defining events (non-ADEs), and death 1997-2008 in Nashville, Tennessee. Cox proportional hazards models compared rates of ADE or all-cause death and non-ADE or all-cause death, and competing risks analyses compared rates of ADE or ADE-related death and non-ADE or non-ADE-related death across the groups. There were two groups: women who stopped HAART postpartum (discontinuation, n = 54) and women who continued HAART postpartum (continuation, n = 69). Fifty percent were African American, 40% had prior non-HAART antiretroviral therapy (ART) use, and 38% had a history of illicit drug use. Median age was 27.5 years, baseline CD4(%) was 532 (34%) and CD4 nadir was 332 cells/mm(3), baseline and peak HIV-1 RNA were 2.6 and 4.32 log(10) copies per milliliter, respectively. Women in the continuation group were older, had lower baseline CD4, CD4%, and CD4 nadir, and had higher peak HIV-1 RNA. In multivariable proportional hazards models, the hazard ratios [95% confidence interval (CI)] of ADE or all-cause death and non-ADE or all-cause death were lower in the continuation group, but not statistically significantly: 0.50 (0.12, 2.12; p = 0.35) and 0.69 (0.24, 1.95; p = 0.48), respectively. The results were similar in competing risks analyses. Despite having characteristics associated with worse prognosis, women who continued HAART postpartum had lower hazard ratio point estimates for ADEs or death and non-ADEs or death than women who discontinued HAART. Larger studies with longer follow-up are indicated to assess this association.

Treatment interruption in chronic HIV-1 infection: does it deliver?

PURPOSE OF REVIEW

This review sets out to overview treatment interruption in chronic HIV-1 infection: what treatment interruption promised, results from recent trials, and what the future holds.

RECENT FINDINGS

Recent studies have produced mixed results; several trials have been prematurely halted, whereas others have reported more positive outcomes. One consistent finding has been the identification of the CD4 T-cell count nadir as a critical parameter in determining the outcome of treatment interruption.

SUMMARY

The use of treatment interruption is still controversial, but it is becoming clear that certain individuals could benefit, and partial treatment interruption strategies warrant further investigation.

Treatment interruption after pregnancy: effects on disease progression and laboratory findings

OBJECTIVE

To assess clinical progression and inflammatory markers among women stopping or continuing antiretroviral therapy (ART) after pregnancy.

METHODS

ART-naïve women with CD4+ lymphocyte counts >350 cells/uL initiating ART during pregnancy had clinical events and laboratory markers compared over one year postpartum between those stopping (n = 59) or continuing (n = 147) ART.

RESULTS

Slopes in CD4 count and HIV RNA did not differ between groups overall and in subsets of ZDV or combination therapy. The hazard ratio (HR) of a new class B event was 2.09 (95% CI 0.79-5.58) among women stopping ART, 1.24 (0.31-4.95) in those stopping ZDV, and 2.93 (0.64-13.36) among those stopping combination therapy. Women stopping ART had increased immune activation. No significant differences were seen in C-reactive protein, lipids, leptin, or interleukin-6.

CONCLUSIONS

While changes in CD4 and HIV RNA levels over one year were similar between women stopping or continuing ART postpartum, higher immune activation among women stopping therapy requires further study.

Lipid and apoprotein profile in HIV-1-infected patients after CD4-guided treatment interruption

OBJECTIVES

The aims of the present study were to determine if metabolic abnormalities and cytokine derangements are modified in HIV-1-infected patients after 12 months on treatment interruption (TI).

DESIGN

The design of this study was prospective randomized study.

METHODS

Longitudinal multicenter study in HIV-1-infected patients with a 12-month follow-up. Patients on stable highly active antiretroviral therapy, with CD4 count >600/microL and HIV RNA <50 copies/mL for at least 6 months, were randomized to interrupt therapy or continue ongoing highly active antiretroviral therapy. Lipids (total cholesterol, triglycerides), apoproteins (A1, B, and E), and adipocytokines (leptin, adiponectin, plasminogen activator inhibitor-1, monocyte chemotactic protein-1, Interleukin-6, Interleukin-8, and tumor necrosis factor-alpha) were measured at baseline and at month 12. Multiplex suspension bead array immunoassay was performed using the Luminex 100 analyzer to identify protein expression in plasma.

RESULTS

Patients who underwent TI (n = 19) had a significant decrease in median cholesterol levels (P < 0.001), while median triglyceride levels remained unchanged. There was a significant decrease in Apo-A1 levels (P = 0.048) and Apo-B levels (P < 0.001) and an increase in tumor necrosis factor-alpha levels (P = 0.034). Given the greater decrease in Apo-B, the ratio Apo-A1/Apo-B increased after 12 months of TI (from 3.4 to 5.1, P = 0.008). We did not find significant variations in leptin or adiponectin levels. In patients who continued on highly active antiretroviral therapy (n = 18), there were no significant changes in any of the measured parameters.

CONCLUSION

The lipid profile and apoproteins levels change toward a less atherogenic profile after TI, arguing against a lipid-mediated mechanism to explain the increased cardiovascular risk in patients who interrupt treatment.