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P Vernazza

Publications and source records attributed to P Vernazza.

26 records · Page 2Linked to original sources

Clinical progression and virological failure on highly active antiretroviral therapy in HIV-1 patients: a prospective cohort study. Swiss HIV Cohort Study.

BACKGROUND: The efficacy of highly active antiretroviral therapy (HAART) in suppression of HIV-1 is well documented. We investigated virological and clinical outcomes of HAART in routine practice. METHODS: We analysed prospective data from the Swiss HIV Cohort Study on suppression of viral load and progression to AIDS or death in 2674 outpatients (median age 36 years, 27.3% women) who started HAART in 1995-98. Viral rebound was defined as two consecutive HIV-1-RNA measurements of more than 400 copies/mL. We analysed separately outcomes in patients with a history of antiretroviral treatment and in treatment-naïve patients. FINDINGS: An estimated 90.7% of treatment-naïve patients reached undetectable viral load (<400 copies/mL) by 12 months. Among pretreated patients, estimates ranged from 70.3% treated with one new drug to 78.7% on three new drugs. 2 years after reaching undetectable concentrations, an estimated 20.1% of treatment-naïve patients and 35.7-40.1% of pretreated patients had viral rebound. At 30 months, an estimated 6.6% (95% CI 4.6-8.6) of patients who had maintained undetectable concentrations, 9.0% (5.5-12.5) who had viral rebound, and 20.1% (15.3-24.9) who had never reached undetectable concentrations developed AIDS or died. Compared with patients who maintained undetectable viral load, the adjusted relative hazard of AIDS or death was 1.00 (0.66-1.55) for patients with viral rebound, and 2.40 (1.72-3.33) for patients who failed to reach undetectable concentrations. INTERPRETATION: The rate of virological failure of HAART was high among these patients, but the probability of clinical progression was low even in patients with viral rebound.

Adult↗

Characterization of V3 sequence heterogeneity in subtype C human immunodeficiency virus type 1 isolates from Malawi: underrepresentation of X4 variants.

We have examined the nature of V3 sequence variability among subtype C human immunodeficiency virus type 1 (HIV-1) sequences from plasma-derived viral RNA present in infected men from Malawi. Sequence variability was assessed by direct sequence analysis of the V3 reverse transcription-PCR products, examination of virus populations by a subtype C V3-specific heteroduplex tracking assay (V3-HTA), and selected sequence analysis of molecular clones derived from the PCR products. Sequence variability in V3 among the subtype C viruses was not associated with the presence of basic amino acid substitutions. This observation is in contrast to that for subtype B HIV-1, where sequence variability is associated with such substitutions, and these substitutions are determinants of altered coreceptor usage. Evolutionary variants in subtype C V3 sequences, as defined by the V3-HTA, were not correlated with the CD4 level in the infected person, while such a correlation was found with subtype B V3 sequences. Viruses were isolated from a subset of the subjects; all isolates used CCR5 and not CXCR4 as a coreceptor, and none was able to grow in MT-2 cells, a hallmark of the syncytium-inducing phenotype that is correlated with CXCR4 usage. The overall sequence variability of the subtype C V3 region was no greater than that of the conserved regions of gp120. This limited sequence variability was also a feature of subtype B V3 sequences that do not carry the basic amino acid substitutions associated with altered coreceptor usage. Our results indicate that altered coreceptor usage is rare in subtype C HIV-1 isolates in sub-Saharan Africa and that sequence variability is not a feature of the V3 region of env in the absence of altered coreceptor usage.

Base Sequence↗

Impact of new antiretroviral combination therapies in HIV infected patients in Switzerland: prospective multicentre study. Swiss HIV Cohort Study.

OBJECTIVES: To examine trends in disease progression and survival among patients enrolled in the Swiss HIV cohort study during 1988-96 and to assess the influence of new antiretroviral combination therapies. DESIGN: Prospective multicentre study, with follow up visits planned at six monthly intervals. SETTING: Seven HIV units at university centres and cantonal hospitals in Switzerland. PATIENTS: 3785 men (mean age 35.0 years) and 1391 women (30.3 years) infected with HIV. 2023 participants had a history of intravenous drug misuse; 1764 were men who had sex with men; 1261 were infected heterosexually; and 164 had other or unknown modes of transmission. 601 participants had had an AIDS defining illness. RESULTS: During more than 15,000 years of follow up, there were 1456 first AIDS defining diagnoses and 1903 deaths. Compared with those enrolled during 1988-90, the risk of progression to a first AIDS diagnosis was reduced by 18% (relative risk 0.82 (95% confidence interval 0.73 to 0.93)) among participants enrolled in 1991-2, by 23% (0.77 (0.65 to 0.91)) among those enrolled in 1993-4, and by 73% (0.27 (0.18 to 0.39)) among those enrolled in 1995-6. Mortality was reduced by 19% (0.81 (0.73 to 0.90)), 26% (0.74 (0.63 to 0.87)), and 62% (0.38 (0.25 to 0.97)) respectively. Compared with no antiretroviral treatment, the risk of an initial AIDS diagnosis after CD4 lymphocyte counts fell to < 200 cells x 10(6)/1 was reduced by 16% (0.84 (0.73 to 0.97)) with monotherapy, 24% (0.76 (0.63 to 0.91)) with dual therapy, and 42% (0.58 (0.37 to 0.92)) with triple therapy. Mortality was reduced by 23% (0.77 (0.68 to 0.88)), 31% (0.69 (0.60 to 0.80)), and 65% (0.35 (0.20 to 0.60)) respectively. CONCLUSIONS: The introduction of antiretroviral combination therapies outside the selected patient groups included in clinical trials has led to comparable reductions in disease progression and mortality.

Acquired Immunodeficiency Syndrome↗

[Prevalence of transmission of zidovudine-resistant viruses in Switzerland. l'Etude suisse de cohorte VIH].

Zidovudine (ZDV) was the most widely used anti-HIV drug between 1987 and 1995, and, as already reported, transmission of ZDV-resistant viruses occurs. Several mutations of the reverse transcriptase gene have been identified; one of them affects the 215 codon and is associated with a high degree of resistance. We have determined, using selective PCR, the prevalence of transmission of 215 mutant isolates in 134 patients with primary HIV infection (PHI) and have identified 8 patients with 215 mutant virus between 1989 and 1995 in Switzerland. Mutant resistant viruses have been isolated from patients treated with most antiviral drugs. A systematic search for mutant viruses may provide useful information for the adaptation of treatment strategies.

Adolescent↗

A controlled study of inhaled pentamidine for primary prevention of Pneumocystis carinii pneumonia.

BACKGROUND: Current recommendations for prophylaxis of Pneumocystis carinii pneumonia (PCP) are based on data from patients who have had at least one episode of PCP (secondary prevention). We designed a study to determine the efficacy and side effects of inhaled pentamidine in the primary prevention of PCP. METHODS: Two hundred twenty-three patients sero-positive for human immunodeficiency virus (HIV) who had the acquired immunodeficiency syndrome (AIDS) but not PCP, who had advanced AIDS-related complex, or who had less than 0.2 x 10(9) CD4-positive lymphocytes per liter received either 300 mg of pentamidine isethionate or 300 mg of sodium isethionate every 28 days by inhaler. The proportion of patients surviving without PCP was analyzed with the log-rank test as a function of time spent in the trial, according to the intention to treat with either placebo or pentamidine. RESULTS: The third of five planned interim analyses showed a significant difference in the occurrence of PCP, with 8 cases in pentamidine group and 23 in the placebo group (nominal P value = 0.0021). There were no deaths within 60 days of the diagnosis of PCP and no significant differences in survival between groups. Approximately 53 inhalations were needed to prevent one episode of pneumonia. Thirty-eight of 114 patients given pentamidine (33 percent) and 7 of 109 given placebo (6 percent) had moderate-to-severe coughing during inhalations (two-tailed P less than 0.00001), which caused 4 patients given pentamidine (3.5 percent) to discontinue taking it. CONCLUSIONS: A dose of 300 mg of aerosolized pentamidine given every four weeks was well tolerated and 60 to 70 percent effective in preventing a first episode of PCP in patients with HIV infection.

AIDS-Related Complex↗

Primary prevention of Pneumocystis carinii pneumonia by inhalation of pentamidine. Preliminary results from a placebo-controlled randomized trial. Swiss Group for Clinical Studies on AIDS.

Patients with AIDS but without pneumocystis carinii pneumonia, patients with advanced AIDS-related complex (ARC), and asymptomatic patients with less than 200 CD4-positive lymphocytes/mm3 were randomized to one of two groups: group I: Inhalation of 300 mg of pentamidine every 28 days; group II: Inhalation of placebo (300 mg of Na isethionate) every 28 days. From May to November 28, 1989, 160 patients have entered the trial. Inhalations were well tolerated, with only a 6% use of bronchodilators and a 15% incidence of cough. Until now five patients died, none of them drug related. So far, six patients have developed pneumocystis carinii pneumonia; four of these were on pentamidine, and two on placebo. Five of the six cases occurred before the second inhalation. Recruitment will continue until 250 patients are enrolled.

Administration, Inhalation↗