Short communication: Apoptosis pathways in HIV-1-infected patients before and after highly active antiretroviral therapy: relevance to immune recovery.

Investigations into apoptotic pathways, intrinsic and extrinsic, and the effects of highly active antiretroviral therapy (HAART) on T cell death via those pathways may provide insight into the mechanisms of and barriers to immune recovery. HIV-1-infected patients were enrolled into a randomized, controlled study of the immune effects of a lopinavir/ritonavir (LPV/r)-based versus an efavirenz (EFV)-based HAART regimen in antiretroviral-naive subjects with CD4(+) counts <350 cells/mm(3). Patients were randomized to receive TDF/FTC/EFZ or TDF/FTC plus LPV/r. Fourteen patients were enrolled and 10 patients completed 6 months of therapy as per the protocol. CD4(+) counts were measured before and during HAART therapy. We isolated T cell subsets to measure ex vivo apoptosis by propidium iodide staining. We also assessed caspase activation for the intrinsic and extrinsic pathways of apoptosis, as well as effector caspase activation. We also measured mitochondrial membrane potential. Cells were analyzed by flow cytometry. All patients had increased activation of caspase 8 (extrinsic pathway), caspase 9 (intrinsic pathway), effector caspases 3/7, and low mitochondrial membrane potential at baseline compared to controls. By 4 weeks, there was a decrease in activation of all caspases, but little further decrease by week 24. T cell mitochondrial membrane potential did not increase until week 12, but continued to increase until week 24. The only predictor of CD4(+) count increase was the increase in mitochondrial membrane potential of naive cells at 6 months (r=0.66, p=0.038). This suggests that positive selection of naive CD4(+) T cells in the thymus is the major determinant of CD4(+) recovery.

Evaluation of myocardial infarction and coronary artery disease in subjects taking lopinavir/ritonavir: a study using clinical trial and pharmacovigilance databases.

OBJECTIVE: There is growing interest in studying age-related diseases, such as coronary artery disease (CAD) and resulting myocardial infarction (MI) in HIV-infected patients. While some cohort studies indicate that several antiretrovirals (ARVs), including the protease inhibitor lopinavir/ ritonavir (LPV/r), are associated with an increased relative risk (RR) of MI, other studies show a reduction of MI and CAD in subjects taking ARVs when compared with HIV+ patients not taking ARV therapy. This manuscript reviews data from Abbott-sponsored clinical trials and pharmacovigilance reporting system. METHODS: A systematic search was performed to retrieve cases of MI and CAD in Abbott's clinical trial and pharmacovigilance safety databases. The rates of MI and CAD, and risk factors for the events were reviewed in detail. RESULTS: The rate of MI and CAD per 1,000 patient treatment years (PTY) was 1.24 (95% CI = 0.40 - 2.90) and 2.74 (95% CI = 1.37 - 4.90), respectively, for subjects taking LPV/r during clinical trials. The frequency of pharmacovigilance reports of MI and CAD were 2.9 per 100,000 PTY and 3.6 per 100,000 PTY, respectively. Most subjects who had MI and CAD events had multiple baseline risk factors. CONCLUSIONS: Relatively few subjects experienced MI or CAD during Abbott-sponsored clinical trials of LPV/r. Analysis of clinical trial and pharmacovigilance data did not indicate an increased risk of MI or CAD associated with LPV/r compared with the general population. In general, the subjects that experienced MI or CAD had known traditional risk factors suggesting that addressing modifiable risk factors could decrease the risk of MI or CAD. ARVs have not been thoroughly studied in subjects at high risk for MI and CAD, and further studies of this population could identify whether starting ARVs affects the incidences of cardic events in subjects with many traditional risk factors

Serum immune activation markers are persistently increased in patients with HIV infection after 6 years of antiretroviral therapy despite suppression of viral replication and reconstitution of CD4+ T cells.

The effect of long-term antiretroviral therapy on serum immune activation markers was assessed in a cohort of 63 patients before and after 6 years of boosted lopinavir-based antiretroviral therapy. High levels of most markers were associated with lower CD4(+) T cell counts at baseline and at year 6, with the exception of soluble cytotoxic T lymphocyte antigen-4 (sCTLA-4); high levels of sCTLA-4 were associated with higher CD4(+) T cell counts at year 6. Abnormalities of serum immune activation markers persisted after 6 years of ART but probably had different causes. Further investigation of the clinical usefulness of assaying immunoglobulin A, neopterin, and sCTLA-4 levels to assess the effectiveness of treatments for human immunodeficiency virus (HIV) disease are warranted.

Differences in rates of diarrhea in patients with human immunodeficiency virus receiving lopinavir-ritonavir or nelfinavir.

STUDY OBJECTIVE: To determine and compare rates of diarrhea in patients receiving an antiretroviral regimen containing lopinavir-ritonavir versus nelfinavir and in patients who received these drugs sequentially. DESIGN: Retrospective cohort analysis. SETTING: Hospital-based human immunodeficiency virus (HIV) clinic. PATIENTS: Four hundred one participants in the HIV Atlanta VA Cohort Study who were prescribed lopinavir-ritonavir or nelfinavir from 1996-2002. MEASUREMENTS AND MAIN RESULTS: Chart review identified episodes of diarrhea that potentially were associated with an antiretroviral agent. Data collected included antidiarrheal agents dispensed, baseline viral load and CD4+ cell counts, demographic variables, and previous therapy Diarrhea associated with an antiretroviral regimen occurred in 175 (49%) of 354 patients receiving nelfinavir and 17 (17%) of 99 patients receiving lopinavir-ritonavir (p < 0.001). Treatment for the diarrhea occurred in 118 (33%) of 354 patients receiving nelfinavir and 9 (9%) of 99 receiving lopinavir-ritonavir (p < 0.001). Patients in the lopinavir-ritonavir group were more likely to have received highly active antiretroviral therapy and azithromycin than patients receiving nelfinavir, and they had lower baseline CD4+ cell counts (p < or = 0.01 for each comparison). The average number of months/person-year of diarrhea treatment was 2.0 for the nelfinavir group and 0.13 for the lopinavir-ritonavir group. Of the 10 antiretroviral-naive patients who received lopinavir-ritonavir, none needed treatment for diarrhea, whereas 78 (36%) of 217 antiretroviral-naive patients who received nelfinavir required treatment for diarrhea. Of the 52 patients who had been taking nelfinavir and were switched to lopinavir-ritonavir, they were more likely to start antidiarrheal treatment while taking nelfinavir (14 [27%]) than while receiving lopinavir-ritonavir (3 [6%]) (p = 0.004). CONCLUSIONS: Patients receiving lopinavir-ritonavir were significantly less likely to have diarrhea or to require treatment for diarrhea than patients receiving nelfinavir. The same results occurred when the drugs were given to the same patients sequentially (nelfinavir followed by lopinavir-ritonavir). The diarrhea associated with lopinavir-ritonavir was less frequent, less severe, and shorter in duration than diarrhea associated with nelfinavir.