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Saquinavir is a peptidomimetic inhibitor of HIV protease. Initially marketed as Invirasetrade mark, the effectiveness of saquinavir was greatly hindered by its nearly complete first pass metabolism by cytochrome P450 3A4. A new formulation, Fortovasetrade mark, appears to yield some six times the drug exposure and has been demonstrated to yield virological and immunological results similar to those of other protease inhibitors (PIs) when used in conjunction with two nucleoside reverse transcriptase inhibitors (nRTIs). Emerging data suggest it is safe to use twice daily. Co-administration of either formulation of saquinavir with nelfinavir and especially ritonavir yields greatly increased blood levels, with corresponding superior magnitude and durability of viral suppression in first line therapy, albeit with increased adverse effects. The combination of ritonavir and saquinavir has also yielded the most promising results published for second line therapy, after virological breakthrough on previous PI-containing therapy. In addition, preliminary data suggests the possibility of once daily dosing of ritonavir and saquinavir, which would be expected to increase compliance and allow for direct observed therapy.

Aim Our aim was to evaluate the effect of ketoconazole on ritonavir and saquinavir plasma and cerebrospinal fluid (CSF) concentrations. Methods Twelve patients who were human immunodeficiency virus–seropositive and who were receiving 400 mg of ritonavir and 400 mg of saquinavir twice daily completed a nonfasted, two-period, two-group, longitudinal pharmacokinetic study. Blood samples were collected over the daytime 12-hour dosing interval of the protease inhibitors at baseline (period 1, day 0) and after 10 days of coadministration of 200 mg (n = 6) or 400 mg (n = 6) of ketoconazole once daily (period 2, day 10). One set of paired CSF and blood samples was collected between 4 and 5 hours after the dose on both days. Results Ketoconazole significantly increased area under the plasma concentration-time curve, plasma concentration at 12 hours after the dose, and half-life of ritonavir by 29% (95% confidence interval (CI), 13%-46%), 62% (95% CI, 37%-92%), and 31% (95% CI, 13%-51%), respectively. Similar increases of 37% (95% CI, 4%-81%), 94% (95% CI, 41%-167%), and 38% (95% CI, 15%-66%), respectively, were observed for these parameters for saquinavir. Ketoconazole significantly elevated ritonavir CSF concentration by 178% (95% CI, 59%-385%), from 2.4 to 6.6 ng/mL, with no change in paired unbound plasma level (26 ng/mL); this led to a commensurate 181% increase (95% CI, 47%-437%) in CSF/plasma unbound ratio. All pharmacokinetic changes were unrelated to ketoconazole dose or plasma exposures. Corresponding changes for saquinavir CSF pharmacokinetics were insignificant (P > .06); saquinavir CSF levels were unmeasurable in 7 patients (

Intravascular lymphoma (IVL) is a rare form of non-Hodgkin lymphoma characterized by proliferation of malignant lymphoid cells limited to the lumen of small vessels. Clinical manifestations are nonspecific and result from vascular obliteration and hypoxia. The disease affects primarily the skin and central nervous system, often associated with rapid systemic dissemination and aggressive clinical course if appropriate therapy is not initiated early. Involvement of the lungs, kidneys, adrenal glands, and prostate may occur. Primary pulmonary IVL is exceedingly rare. We describe a case of primary pulmonary IVL in an HIV-positive man presenting with nonspecific constitutional symptoms. High-resolution computed tomography demonstrated centrilobular nodules with ground-glass attenuation and peribronchial ground-glass opacities. The diagnosis was confirmed by thoracoscopic biopsy and histologic findings consisted of accumulation of malignant lymphocytes within alveolar capillaries, pulmonary veins, and peribronchial arterioles. Immunohistochemistry confirmed positivity for CD20, a marker for B lymphocytes. Combined systemic chemotherapy including rituximab was started and resulted in significant clinical and radiologic improvement with long-term disease-free survival.

BACKGROUND Dramatic reductions in plasma HIV RNA levels are possible with current antiretroviral regimens; the effect of potent therapies and "undetectable" viral load on the perceived risk of HIV transmission and need for safer practices remains unknown. METHODS A questionnaire was developed to examine perceptions of HIV transmission risk and need for safer practices with unprotected anal, vaginal, and oral sex and intravenous drug use with needle sharing for HIV-discordant couples in which the HIV-infected partner was receiving no therapy, was receiving reverse transcriptase inhibitor therapy, and protease inhibitor (PI)-based therapy with viral load "undetectable". This was applied anonymously to 147 unselected HIV-infected individuals attending a university-based HIV clinic. RESULTS Almost all respondents believed that all sexual activities except oral sex were "very risky" and that safer practices were "extremely important" for those not receiving antiretroviral agents. Significantly fewer considered that anal or vaginal sex was "very risky" for those receiving PI therapy (90.9% and 86.0%, respectively), and fewer thought that safer practices for anal or vaginal sex were "very important" for those receiving PI therapy (93.0% and 91.6%, respectively). In total, 20.4% thought the risk of HIV transmission for at least one activity was reduced for those receiving PI therapy, and 19.0% believed that the need for safer practices was reduced by PI therapy. CONCLUSION A small but significant proportion of HIV-infected people perceive the need for safer practices to be reduced during antiretroviral therapy, particularly those containing PIs. Even if the risk is truly reduced, the importance of safer practices should be conveyed consistently and terms such as "undetectable" to describe HIV RNA responses should be avoided.

Disseminated Mycobacterium avium complex (MAC) infection is common in persons with advanced HIV infection and can be prevented by prophylactic use of rifabutin; however, routine prophylaxis is costly and incompletely effective. Chronic anemia is a common manifestation of MAC infection. We conducted a retrospective population study of the annual incidence of MAC bacteremia and blood transfusion for anemia in a regional HIV-positive population before and after the introduction of rifabutin to determine the effect of MAC prophylaxis on the incidence of transfusion-requiring anemia. The HIV-infected patient populations in 1992 and 1993 were comparable in number, severity of immunodeficiency, and zidovudine (ZDV) use. The use of rifabutin for MAC prophylaxis for those with CD4 T-lymphocyte counts < 100/microl increased from 17.2% in 1992 to 33.7% in 1993 (p < 0.001), whereas diagnostic surveillance for MAC bacteremia was stable. In 1993, there was a decrease in the number of HIV-infected persons from whom MAC was isolated (10 vs. 26, p = 0.004), and a significant decrease in the number of patients transfused for anemia (15 vs. 35, p = 0.002), number of transfusion episodes, and numbers of units transfused, associated with significant cost and resource savings. Adoption of MAC prophylaxis was followed by a significant decrease in the number of diagnosed MAC infections and in transfusion requirements in an HIV-positive population with sustained surveillance and similar levels of immunodeficiency, which may represent a health and economic benefit of effective [correction of defective] MAC prophylaxis in a population at risk.

A 55-year-old man who was recently diagnosed with HIV/AIDS developed multiple bilateral pulmonary nodules after starting highly active antiretroviral therapy. Workup confirmed the diagnosis of pulmonary hyalinizing granuloma. This is the first described case of pulmonary hyalinizing granuloma in HIV/AIDS, and may represent a rare form of immune reconstitution inflammatory syndrome.

OBJECTIVE To determine the safety of discontinuing Pneumocystis jiroveci pneumonia (PCP) prophylaxis, in patients on effective antiretroviral therapy with CD4+ T-cell counts that have plateaued at < 200 cells/microl. METHODS We prospectively evaluated a cohort of HIV infected patients at a multidisciplinary HIV clinic with sustained HIV RNA levels < 50 copies/ml and CD4+ T-cell counts that have plateaued at < 200 cells/microl and who have discontinued PCP prophylaxis. RESULTS Nineteen patients fulfilled the above criteria. Eleven had been taking daily trimethoprim-sulfamethoxazole, seven were receiving monthly aerosolized pentamidine, and one patient never received any prophylaxis. The median CD4+ T-cell count at the time of discontinuation and at the most recent determination were 120 (range, 34-184) and 138 (range, 6-201) cells/microl, respectively. To date, patients have been off PCP prophylaxis for a mean of 13.7 +/- 10.6 months and a median of 9.0 (range 3-39) months for a total of 261 patient-months. To date, no patient has developed PCP. This is significantly different from the risk of developing PCP with a CD4+ T-cell count of < 200 cells/microl in untreated HIV infection (rate difference 9.2%; 95% confidence interval, 5.7 to 12.8%; P < 0.05). CONCLUSION With sustained suppression of viral replication, PCP prophylaxis may not be necessary, regardless of CD4+ T-cell count. This illustrates a degree of immune recovery that occurs with virologic suppression that is not reflected in absolute CD4+ T-cell count or percentage and suggests that guidelines for P. jiroveci pneumonia prophylaxis may need to be re-evaluated.

When prescribed appropriately and taken adherently, antiretroviral therapy can consistently and durably suppress HIV replication, potentially translating into years of near normal health for HIV-infected persons. However, presently available antiretrovirals are associated with a cluster of physical and metabolic symptoms termed HIV lipodystrophy. This article reviews the state of knowledge about the pathogenesis and treatment of the various manifestations of these adverse effects.

An HIV-1 infected man who experienced rapid disease progression and poor response to therapy after starting a new sexual relationship with an infected partner is known as the 'Ottawa superinfection case'. Subsequent analysis of viral sequences of protease, reverse transcriptase, Gag p17, and Env V3 provided no evidence for the acquisition of genetically divergent viruses before disease progression or drug resistance during virological failure of combination therapy. Whether HIV-1 superinfection contributes to disease progression or the spread of drug-resistant HIV-1 remains unknown.

Objectives Natural killer (NK) cell function is likely to be important in controlling HIV infection and opportunistic pathogens. We therefore evaluated NK function and phenotype over the course of antiretroviral therapy (ART) and examined the potential mechanisms of altered NK activity in HIV infection. Methods We measured NK cell percentage, NK cytolytic activity (both by flow cytometry) and plasma IL-10 concentrations (by enzyme-linked immunosorbent assay) in 10 HIV-seropositive patients before and over one year of effective ART. To examine potential mechanisms of altered NK activity, we measured NK receptor expression in ART treated and untreated HIV-positive individuals by flow cytometry. As IL-10 enhances NK activity, we studied the effect of IL-10 on NK receptor expression and activity in peripheral blood mononuclear cells (PBMC) from HIV-seronegative individuals. Results NK cytolytic activity was elevated in HIV infection and decreased with ART to levels observed in HIV-negative individuals. A greater proportion of NK cells from untreated HIV-positive individuals expressed the NK receptors CD158a and CD161 than either HIV-negative volunteers or effectively treated HIV-positive patients. NK cells from PBMC incubated with IL-10 demonstrated increases in CD158a, CD161 and CD94 expression and increases in cytolytic activity. The treatment-associated decrease in NK activity paralleled a decrease in IL-10 production. Conclusion The observation that IL-10 alters NK receptor expression similar to that observed in HIV infection, and the fact that NK receptor expression and activity normalize in parallel with ART-induced reduction of circulating IL-10 levels supports a role for IL-10 in NK cell activity and HIV immunopathogenesis.

The dramatic clinical benefit of highly active antiretroviral therapy has been offset, to an extent, by the development of unforeseen long-term toxicities. Of these, the HIV lipodystrophy syndrome is most prominent. The array of related but possibly separate manifestations includes fat deposition and atrophy and metabolic complications such as hyperlipidemias and diabetes mellitus. These have been attributed to the use of protease inhibitors, but other factors may be involved, particularly the use of nucleoside reverse transcriptase inhibitors, especially stavudine. The pathogenesis of any of the manifestations of the syndrome remains to be explained. The metabolic complications may respond to standard treatments, but most therapies directed at fat changes have been unsuccessful. This review will summarize the state of knowledge in the field.

Antiretroviral treatment of patients infected with HIV results in improvements in CD4+ T cell number. Emerging evidence suggests that some of the improvements in CD4+ T cell number that occur in response to protease inhibitor (PI) therapy may not be accounted for solely by enhanced viral suppression, implying that PI may directly affect T cell survival. Since HIV T cell depletion is associated with enhanced apoptosis, we analyzed the effect of PIs on T cell apoptosis. In vitro treatment of peripheral blood lymphocytes (PBLs) from HIV-infected but untreated patients with reverse transcriptase inhibitors (RTIs) does not alter apoptosis, whereas PI treatment rapidly reduces CD4+ and CD8+ T cell apoptosis. In contrast, PI treatment does not alter apoptosis in PBL blasts from HIV-negative patients, or in Jurkat T cells. Consistent with this observation, 8 days of PI therapy in HIV-infected patients does not significantly alter plasma viremia, yet results in significant inhibition of CD4+ and CD8+ T cell apoptosis. The inhibitory effects of PI on apoptosis have implications concerning the treatment of HIV and its pathogenesis.

The degree of immune recovery achievable with anti-human immunodeficiency virus (HIV) therapy remains to be established. The effects of potent antiretroviral therapy, including ritonavir and saquinavir, on immune function were studied for a prolonged period in 41 patients. After 96 weeks, 88% of patients had plasma HIV RNA levels below the limit of quantitation. There were continuous increases in CD4 lymphocyte counts and in CD4:CD8 ratios over time. About half the patients developed lymphoproliferative responses to HIV p24 antigen, and nearly all developed responses to phytohemagglutinin. This occurred in parallel with increases in interleukin-12 production and expression of CD28 on CD8 lymphocytes, despite potential antiproliferative effects of protease inhibitors. Transient increases in virus load were temporally associated with loss of proliferative responses. The improved immune function, including HIV-specific immunity in many subjects, demonstrates the potential reversibility of HIV-induced immunodeficiency and does not identify a limit to immune recovery.

T cells from HIV infected patients undergo spontaneous apoptosis at a faster rate than those from uninfected patients, are abnormally susceptible to activation induced cell death (AICD), and undergo increased apoptosis in response to Fas receptor ligation. These observations have led to the hypothesis CD4 T cell apoptosis may be a mechanism of CD4 T cell depletion and the pathogenesis of AIDS. Successful treatment of HIV infected patients is accompanied by quantitative and qualitative improvements in immune function reflecting at least partial reversibility of the underlying pathogenesis of HIV. In this report we correlate improvements in markers of immune function with a decrease in apoptosis, and changes in its regulation. Therapy with nelfinavir plus saquinavir in combination with two nucleoside analogue inhibitors of reverse transcriptase dramatically reduces plasma viremia and increases CD4 T cell counts. Coincident with these improvements, CD38 and HLA-DR coexpression on both CD4 and CD8 T cells decrease, and CD45RA and CD62L coexpression increase. Furthermore, spontaneous apoptosis decreases in both CD4 and CD8 T cells (CD4 apoptosis 17.4 vs 2.6%, P=0.005; CD8 apoptosis 15.0 vs 1.0%, P

Eight patients with infection due to human immunodeficiency virus type 1 developed fat pads at the bases of their necks a median of 22 weeks (range, 4-61 weeks) after initiation of protease inhibitor therapy. This finding was seen in association with the use of each of the available protease inhibitors. The patients had no other cushingoid features or histories of corticosteroid use, and all had normal 24-hour urine cortisol levels. The computed tomography scans of five patients showed large, nonencapsulated accumulations of subcutaneous adipose tissue. Histological examination of tissue from one patient confirmed a nonlipomatous subcutaneous fat deposition. Although the pathogenesis of this unique clinical finding is unclear, the temporal relationship between the use of protease inhibitors and the development of cervical fat pads is suggestive of a complication of therapy.

Background. Ritonavir is a potent, orally bioavailable inhibitor of HIV-1 protease. We undertook an international, multicentre, randomised, double-blind, placebo-controlled trial of ritonavir in patients with HIV-1 infection and CD4-lymphocyte counts of 100 cells/μL or less, who had previously been treated with antiretroviral drugs. Methods. 1090 patients were randomly assigned twice-daily liquid oral ritonavir 600 mg (n = 543) or placebo (n = 547) while continuing treatment with up to two licensed nucleoside agents. The primary study outcome was any first new, or specified recurrent, AIDS-defining event or death. Open-label ritonavir was provided after 16 weeks in the study to any patient who had an AIDS-defining event. Findings. The baseline median CD4-lymphocyte count was 18 (IQR 10-43)/μL in the ritonavir group and 22 (10-47)/μL in the placebo group. Study medication was discontinued in 114 (21.1%) ritonavir-group patients and 45 (8.3%) placebo-group patients mainly because of initial adverse symptoms. Outcomes of AIDS-defining illness or death occurred in 119 (21.9%) ritonavir-group patients and 205 (37.5%) placebo-group patients (hazard ratio 0.53 [95% CI 0.42-0.66]; log-rank p < 0.0001) during median follow-up of 28.9 weeks, with loss to follow-up of 15 (1.4%) patients. Ritonavir was then offered to all patients; at median follow-up of 51 weeks, 87 (16%) ritonavir-group patients had died of any cause versus 126 (23%) placebo-group patients (hazard ratio 0.69 [95% CI 0.52-0.91], log-rank p = 0.0072). Interpretation. Although earlier intervention with combination therapy may provide much more effective treatment, ritonavir in patients with advanced disease and extensive previous antiretroviral use is safe and effective, lowers the risk of AIDS complications, and prolongs survival.

(2009). HIV Essentials By Paul E. Sax, Calvin J. Cohen, and Daniel R. Kuritzkes. Jones & Bartlett Publishers, 2008, 200 pp. HIV Clinical Trials: Vol. 10, No. 1, pp. 63-63.

Background: Acquired immunodeficiency syndrome (AIDS) has become a leading cause of death of young men in the United States. With the introduction of prophylaxes and antiretrovirals for opportunistic infection, there have been significant changes in the clinical history of human immunodeficiency virus (HIV) infection. Objective: To determine the cause of death of the patients followed up by our clinic from 1984 to 1995. Methods: A critical chart review was performed on the records of all patients affiliated with the Ottawa General Hospital HIV/AIDS Clinic, Ottawa, Ontario, who died between 1984 and July 15, 1995. Data regarding the cause of death, last CD4 T-lymphocyte cell count before death, medication use at time of death, and location and year of death were collected. Data were analyzed for 1984 through 1988, 1989 through 1991, and 1992 through 1995, corresponding to the evolution of HIV-related medical care. Results: The median CD4 T-lymphocyte cell count at death has declined. Pneumocystis carinii pneumonia has decreased significantly as cause of death (28.6%-3.8%, p p =.04), and untreatable illnesses have increased in frequency as causes of death. Patients are increasingly likely to die at home (0%-25%, P P Conclusions: The HIV-infected persons are dying with more advanced HIV immunosuppression. Advances in P carinii pneumonia prophylaxis and treatment have had a dramatic effect on the cause of death of HIV-infected persons. Improved prophylaxis and treatment for non— P carinii pneumonia opportunistic infections and malignancies and HIV wasting syndrome are required. Arch Intern Med. 1997;157:2069-2073