Atazanavir and darunavir in pregnant women with HIV: evaluation of laboratory and clinical outcomes from an observational national study

Background

Atazanavir and darunavir represent the main HIV PIs recommended in pregnancy, but comparative data in pregnant women are limited. We assessed the safety and activity profile of these two drugs in pregnancy using data from a national observational study.

Methods

Women with atazanavir or darunavir exposure in pregnancy were evaluated for laboratory measures and main pregnancy outcomes (e.g. preterm delivery, low birthweight, non-elective caesarean section and neonatal gestational age-adjusted birthweight Z-score).

Results

Final analysis included 500 pregnancies with either atazanavir (n = 409) or darunavir (n = 91) exposure. No differences in pregnancy outcomes, weight gain in pregnancy, drug discontinuations, undetectable HIV-RNA, haemoglobin, ALT, total cholesterol, HDL cholesterol and LDL cholesterol were observed between the two groups. At third trimester, exposure to darunavir was associated with higher levels of plasma triglycerides (median 235.5 versus 179 mg/dL; P = 0.032) and a higher total cholesterol/HDL cholesterol ratio (median 4.03 versus 3.27; P = 0.028) and exposure to atazanavir was associated with higher levels of plasma bilirubin (1.54 versus 0.32 mg/dL; P < 0.001).

Conclusions

In this observational study, the two main HIV PIs currently recommended by perinatal guidelines showed similar safety and activity in pregnancy, with no evidence of differences between the two drugs in terms of main pregnancy outcomes. Based on the minor differences observed in laboratory measures, prescribing physicians might prefer either drug in some particular situations where the different impacts of treatment on lipid profile and bilirubin may have clinical relevance.

Delayed diagnosis and treatment of tuberculosis in HIV+ patients in Mozambique: A cost-effectiveness analysis of screening protocols based on four symptom screening, smear microscopy, urine LAM test and Xpert MTB/RIF

Background

Tuberculosis (TB) represents the ninth leading cause of death worldwide. In 2016 are estimated 1.3 million TB deaths among HIV negative people and an additional 374,000 deaths among HIV positive people. In 2016 are estimated 1.4 million new cases of TB in people living with HIV (PLHIV), 74% of whom were living in Africa. In light of these data, the reduction of mortality caused by TB in PLHIV is strongly required specially in low-income countries as Mozambique. According to international guidelines, the initial TB screening in HIV+ patients should be done with the four symptoms screening (4SS: fever, current cough, night sweats and weight loss). The diagnostic test more used in resource-limited countries is smear microscopy (SMEAR). World Health Organization (WHO) recommended Lateral Flow urine LipoArabinoMannan assay (LF-LAM) in immunocompromised patients; in 2010 WHO endorsed the use of Xpert Mycobacterium Tuberculosis/Rifampicin (MTB/RIF) test for rapid TB diagnosis but the assay is not used as screening test in all HIV+ patients irrespectively of symptoms due to cost and logistical barriers. The paper aims to evaluate the cost-effectiveness of three screening protocols: standard (4SS and SMEAR in positive patients to 4SS); MTB/RIF; LF-LAM / MTB/RIF.

Methods

We developed a model to assess the cost-effectiveness of the MTB/RIF protocol versus the common standard and LF-LAM / MTB/RIF protocol. The model considered a sample of 1,000 HIV+ antiretroviral treatment naïve patients in Mozambique. We evaluated disability-adjusted life year (DALY) averted for each protocol, cost per DALY, and incremental cost-effectiveness ratio (ICER), over 1-year, assuming a national healthcare system perspective. The model considered the delayed diagnosis as the time elapsed between a false negative test and the diagnosis and treatment of TB. Additional health system organization delay is defined as the time interval between positive test and treatment initiation caused by a delay in the delivery of results due organization of services. We conducted a sensitivity analysis on more relevant variables.

Results

The MTB/RIF protocol was cost-effective as compared to the standard protocol with an ICER of $56.54 per DALY saved. In a cohort of 1,000 patients MTB/RIF and LF-LAM / MTB/RIF protocol generated 1,281 and 1,254 DALY’s saved respectively, with a difference of 174 and 147 DALY respect to the standard protocol. The total cost of MTB/RIF protocol was lower ($92,263) than the standard ($147,226) and the LF-LAM / MTB/RIF ($113,196). Therefore, the cost per DALY saved including new infections due to delayed diagnosis with the standard protocol was $79.06, about 5 fold higher than MTB/RIF and LF-LAM / MTB/RIF protocols. The cost of additional TB infections due to delays in diagnosis plus health system delay seemed the more relevant costs. The low sensibility and sensitivity of the standard protocol led to a high number of false negatives, thus delayed TB diagnoses and treatment lead to the development of newly transmitted TB infections.

Conclusions

Our study shows that the MTB/RIF adoption could lead to an increasing of TB case-finding and a reduction in costs compared with standard and LF-LAM / MTB/RIF protocols.

Rate, correlates and outcomes of repeat pregnancy in HIV-infected women

OBJECTIVES

The aim of the study was to assess the rate, determinants, and outcomes of repeat pregnancies in women with HIV infection.

METHODS

Data from a national study of pregnant women with HIV infection were used. Main outcomes were preterm delivery, low birth weight, CD4 cell count and HIV plasma viral load.

RESULTS

The rate of repeat pregnancy among 3007 women was 16.2%. Women with a repeat pregnancy were on average younger than those with a single pregnancy (median age 30 vs. 33 years, respectively), more recently diagnosed with HIV infection (median time since diagnosis 25 vs. 51 months, respectively), and more frequently of foreign origin [odds ratio (OR) 1.36; 95% confidence interval (CI) 1.10-1.68], diagnosed with HIV infection in the current pregnancy (OR: 1.69; 95% CI: 1.35-2.11), and at their first pregnancy (OR: 1.33; 95% CI: 1.06-1.66). In women with sequential pregnancies, compared with the first pregnancy, several outcomes showed a significant improvement in the second pregnancy, with a higher rate of antiretroviral treatment at conception (39.0 vs. 65.4%, respectively), better median maternal weight at the start of pregnancy (60 vs. 61 kg, respectively), a higher rate of end-of-pregnancy undetectable HIV RNA (60.7 vs. 71.6%, respectively), a higher median birth weight (2815 vs. 2885 g, respectively), lower rates of preterm delivery (23.0 vs. 17.7%, respectively) and of low birth weight (23.4 vs. 15.4%, respectively), and a higher median CD4 cell count (+47 cells/μL), with almost no clinical progression to Centers for Disease Control and Prevention stage C (CDC-C) HIV disease (0.3%). The second pregnancy was significantly more likely to end in voluntary termination than the first pregnancy (11.4 vs. 6.1%, respectively).

CONCLUSIONS

Younger and foreign women were more likely to have a repeat pregnancy; in women with sequential pregnancies, the second pregnancy was characterized by a significant improvement in several outcomes, suggesting that women with HIV infection who desire multiple children may proceed safely and confidently with subsequent pregnancies.

Virological failure at one year in triple-class experienced patients switching to raltegravir-based regimens is not predicted by baseline factors

We evaluated rates and determinants of virological failure in triple-class experienced patients receiving raltegravir-based regimens from a national observational study over 48 weeks, defined by any one of the following: (1) no HIV-RNA suppression to undetectable levels (<50 copies/mL) during follow-up; (2) detectable viral load after obtaining undetectable levels; and (3) leaving the study before 48 weeks. Among 101 eligible patients, 26 (25.7%; 95% CI 17.2–34.2) had virological failure. No significant differences between patients with and without virological failure were observed for gender, age, route of transmission, baseline CD4/HIV-RNA, CDC group, hepatitis B or C co-infections, resistance (based on the last genotype available), type and number of concomitant drug classes, concomitant use of darunavir, atazanavir, etravirine, enfuvirtide or maraviroc, and health-related quality-of-life measures. A high rate of treatment response was observed. The analyses did not identify any baseline factor associated with failure, including resistance status. Even if we cannot exclude the presence of pre-existing minority resistant variants not captured by genotypic tests, the lack of baseline predictors of failure suggests the need to monitor patients closely during follow up for other factors, such as potential drug interactions and reduced levels of adherence, which may favour virological failure.

Amniocentesis and chorionic villus sampling in HIV-infected pregnant women: a multicentre case series

OBJECTIVES

To assess in pregnant women with HIV the rates of amniocentesis and chorionic villus sampling (CVS), and the outcomes associated with such procedures.

DESIGN

Observational study. Data from the Italian National Program on Surveillance on Antiretroviral Treatment in Pregnancy were used.

SETTING

University and hospital clinics.

POPULATION

Pregnant women with HIV.

METHODS

Temporal trends were analysed by analysis of variance and by the Chi-square test for trend. Quantitative variables were compared by Student's t-test and categorical data by the Chi-square test, with odds ratios and 95% confidence intervals calculated.

MAIN OUTCOME MEASURES

Rate of invasive testing, intrauterine death, HIV transmission.

RESULTS

Between 2001 and 2015, among 2065 pregnancies in women with HIV, 113 (5.5%) had invasive tests performed. The procedures were conducted under antiretroviral treatment in 99 cases (87.6%), with a significant increase over time in the proportion of tests performed under highly active antiretroviral therapy (HAART) (100% in 2011-2015). Three intrauterine deaths were observed (2.6%), and 14 pregnancies were terminated because of fetal anomalies. Among 96 live newborns, eight had no information available on HIV status. Among the remaining 88 cases with either amniocentesis (n = 75), CVS (n = 12), or both (n = 1), two HIV transmissions occurred (2.3%). No HIV transmission occurred among the women who were on HAART at the time of invasive testing, and none after 2005.

CONCLUSIONS

The findings reinforce the assumption that invasive prenatal testing does not increase the risk of HIV vertical transmission among pregnant women under suppressive antiretroviral treatment.

TWEETABLE ABSTRACT

No HIV transmission occurred among women who underwent amniocentesis or CVS under effective anti-HIV regimens.

Lipid Profile During Pregnancy in HIV-Infected Women

PURPOSE

We investigated the evolution of serum lipid levels in HIV-infected pregnant women and the potential effect of antiretroviral treatment during pregnancy using data from a national surveillance study.

METHOD

Fasting lipid measurements collected during routine care in pregnancy were used, analyzing longitudinal changes and differences in lipid values at each trimester by protease inhibitors (PIs) and stavudine use. Multivariate analyses were used to control for simultaneous factors potentially leading to hyperlipidemia. Study population included 248 women.

RESULTS

Lipid values increased progressively and significantly during pregnancy: mean increases between the first and third trimesters were 141.6 mg/dL for triglycerides (p < .001), 60.8 mg/dL for total cholesterol (p < .001), 13.7 mg/dL for HDL cholesterol (p < .001), and 17.8 mg/dL for LDL cholesterol (p = .001). At all trimesters, women on PIs had significantly higher triglyceride values compared to women not on PIs. The effect of PIs on cholesterol levels was less consistent. Stavudine showed a dyslipidemic effect at first trimester only. Multivariate analyses confirmed these observations and suggested a potential role of other cofactors in the development of hyperlipidemia during pregnancy.

CONCLUSION

The changes observed point to the need to further explore the causes and the clinical correlates of hyperlipidemia during pregnancy in women with HIV.

Rate, predictors, and consequences of late antenatal booking in a national cohort study of pregnant women with HIV in Italy

OBJECTIVE

To evaluate the prevalence and consequences of late antenatal booking (13 or more weeks gestation) in a national observational study of pregnant women with HIV.

METHODS

The clinical and demographic characteristics associated with late booking were evaluated in univariate analyses using the Mann-Whitney U test for quantitative data and the chi-square test for categorical data. The associations that were found were re-evaluated in multivariable logistic regression models. Main outcomes were preterm delivery, low birthweight, nonelective cesarean section, birth defects, undetectable (<50 copies/mL) HIV plasma viral load at third trimester, delivery complications, and gender-adjusted and gestational age-adjusted Z scores for birthweight.

RESULTS

Rate of late booking among 1,643 pregnancies was 32.9%. This condition was associated with younger age, African provenance, diagnosis of HIV during pregnancy, and less antiretroviral exposure. Undetectable HIV RNA at third trimester and preterm delivery were significantly more prevalent with earlier booking (67.1% vs 46.3%, P < .001, and 23.2% vs 17.6, P = .010, respectively), whereas complications of delivery were more common with late booking (8.2% vs 5.0%, P = .013). Multivariable analyses confirmed an independent role of late booking in predicting detectable HIV RNA at third trimester (adjusted odds ratio [AOR], 1.7; 95% CI, 1.3-2.3; P < .001) and delivery complications (AOR, 1.8; 95% CI, 1.2-2.8; P = .005).

CONCLUSIONS

Late antenatal booking was associated with detectable HIV RNA in late pregnancy and with complications of delivery. Measures should be taken to ensure an earlier entry into antenatal care, particularly for African women, and to facilitate access to counselling and antenatal services. These measures can significantly improve pregnancy management and reduce morbidity and complications in pregnant women with HIV.

Birth defects in a national cohort of pregnant women with HIV infection in Italy, 2001-2011

OBJECTIVE

We used data from a national study of pregnant women with HIV to evaluate the prevalence of congenital abnormalities in newborns from women with HIV infection.

DESIGN

Observational study.

SETTING

University and hospital clinics.

POPULATION

Pregnant women with HIV exposed to antiretroviral treatment at any time during pregnancy.

METHODS

The total prevalence of birth defects was assessed on live births, stillbirths, and elective terminations for fetal anomaly. The associations between potentially predictive variables and the occurrence of birth defects were expressed as odds ratios (ORs) with 95% confidence intervals (95% CIs) for exposed versus unexposed cases, calculated in univariate and multivariate logistic regression analyses.

MAIN OUTCOME MEASURES

Birth defects, defined according to the Antiretroviral Pregnancy Registry criteria.

RESULTS

A total of 1257 pregnancies with exposure at any time to antiretroviral therapy were evaluated. Forty-two cases with major defects were observed. The total prevalence was 3.2% (95% CI 1.9-4.5) for exposure to any antiretroviral drug during the first trimester (23 cases with defects) and 3.4% (95% CI 1.9-4.9) for no antiretroviral exposure during the first trimester (19 cases). No associations were found between major birth defects and first-trimester exposure to any antiretroviral treatment (OR 0.94, 95% CI 0.51-1.75), main drug classes (nucleoside reverse transcriptase inhibitors, OR 0.95, 95% CI 0.51-1.76; non-nucleoside reverse transcriptase inhibitors, OR 1.20, 95% CI 0.56-2.55; protease inhibitors, OR 0.92, 95% CI 0.43-1.95), and individual drugs, including efavirenz (prevalence for efavirenz, 2.5%).

CONCLUSIONS

This study adds further support to the assumption that first-trimester exposure to antiretroviral treatment does not increase the risk of congenital abnormalities.

Prevalence and characteristics of symptomatic and asymptomatic tuboovarian masses in women with HIV: an ultrasonographic study

HIV-positive women with pelvic inflammatory disease have been reported to have an increased prevalence of tuboovarian masses (TOMs). The aim of this study was to assess the prevalence of asymptomatic ultrasonographic TOMs in women with HIV and to identify associated factors in order to formulate a selective ultrasonographic screening strategy. Two-hundred and four HIV outpatients underwent transvaginal ultrasonography. Eight (3.9%) had a diagnosis of TOM (5 were asymptomatic). Two profiles of patients at risk for TOM were identified who could be considered for selective screening strategies: the 'long-term infected' (age>35 years, diagnosis of HIV infection more than 5 years ago, HIV clinical category C, CD4 counts below 200/mm(3), >5 lifetime partners and on antiretroviral therapy) and the 'recently diagnosed with HIV' (African ethnicity, age 25-35, HIV diagnosis in the previous year, >5 lifetime partners, HIV clinical category C and not on antiretroviral therapy).

Efficacy and safety of atazanavir in patients with end-stage liver disease

BACKGROUND

No data are available on the use of atazanavir (ATV) in patients with end-stage liver disease (ESLD), and guidelines discourage its use in this setting. The objective of our study was to evaluate the efficacy and safety of unboosted ATV in patients infected with HIV and suffering from ESLD who had been screened for orthotopic liver transplantation (OLT(x)).

PATIENTS AND METHODS

This was a single-arm, 24-week pilot study. Atazanavir-naïve patients undergoing a highly active antiretroviral therapy were switched to ATV 400 mg daily plus two non-thymidine nucleoside reverse transcriptase inhibitors.

RESULTS

Fifteen patients (ten males and five females, age range 36-59 years) were enrolled in the study. Of these, 11 (73%) had a baseline CD4 cell count > 200 microl(-1), and 12 had undetectable plasma HIV-RNA. 12 subjects (80%) were able to remain on ATV until week 24 (n = 10) or transplantation (n = 2). At the end of the study, the median CD4 cell count was 340 microl(-1) , and nine of the ten patients had undetectable RNA. During the study period, two patients received a transplant, two died of intracerebral hemorrhage and lactic acidosis, respectively, and one discontinued ATV. Among the ten patients completing the 24-week study, no significant changes from baseline were observed for most of the liver function markers, with the exception of unconjugated bilirubin (from 1.15 mg/dl to 1.32 mg/dl, p = 0.047).

CONCLUSIONS

Unboosted ATV treatment did not worsen liver disease and was able to maintain or gain immunovirological eligibility for OLT(x) in all patients, with a limited effect on unconjugated bilirubin. These results suggest that ATV is an easy-to-use drug in patients with ESLD.

Pregnancy outcomes and antiretroviral treatment in a national cohort of pregnant women with HIV: overall rates and differences according to nationality

We used data from the main surveillance study of HIV and pregnancy in Italy to evaluate possible differences in pregnancy care and outcomes according to nationality. Among 960 women followed in 2001-06, 33.5% were of foreign nationality, mostly from African countries. Foreign women had lower rates of preconception counselling and planning of pregnancy. They had more frequently HIV diagnosed during pregnancy, with a later start of antiretroviral treatment and lower treatment rates at all trimesters but not when the entire pregnancy, including delivery, was considered. No differences were observed between the two groups in ultrasonography assessments, hospitalisations, AIDS events, intrauterine or neonatal deaths, and mode and complications of delivery. Foreign women had a slightly lower occurrence of preterm delivery and infants with low birthweight. The results indicate good standards of care and low rates of adverse outcomes in pregnant women with HIV in Italy, irrespective of nationality. Specific interventions, however, are needed to increase the rates of counselling and HIV testing before pregnancy in foreign women.

Pharmacokinetics of nelfinavir in HIV-1-infected pregnant and nonpregnant women

AIMS

To compare steady-state nelfinavir (NFV) pharmacokinetics in pregnant and nonpregnant HIV-infected women.

METHODS

Twenty-five pregnant HIV-infected women were selected from an ongoing observational study evaluating the pharmacokinetics of antiretroviral agents during pregnancy. Twenty of them were in the third and five in the second trimester. Data for the control group of 21 HIV-infected nonpregnant women were taken from a previous multicentre pharmacokinetic trial. All the participating women achieved steady-state plasma concentrations while on a highly active antiretroviral therapy (HAART) regimen including NFV (1250 mg bid) and two nucleoside reverse transcriptase inhibitors (NRTIs). Blood samples for NFV measurement were collected predose (C(trough)) and at 0.5, 1, 2, 3, 4, 5, 6, 8 and 12 h post dose.

RESULTS

During the third trimester of pregnancy NFV AUC(0-12 h) median (range) values were 25.76 (12.61-42.74) microg h(-1) ml(-1), and were 32.49 (19.16-63.81) microg h(-1) ml(-1) in the control group [mean difference - 9.30 microg h(-1) ml(-1); 95% confidence interval (CI) -15.76, -2.83; P < 0.05). Median oral clearance (CL/F) was significantly higher in pregnant women than in the control group (48.5 l h(-1), range 29.3-99.1 l h(-1) vs. 38.5 l h(-1), range 19.6-65.2 l h(-1); mean difference 12.6 l h(-1); 95% CI 3.3, 21.9) but the difference disappeared when CL/F was adjusted for body weight. C(trough) was significantly (P < 0.01) lower in pregnant compared with nonpregnant women (median 0.8 microg ml(-1), range 0-2.6 microg ml(-1) vs. 1.5 microg ml(-1), range 0.5-4.9 microg ml(-1); mean difference -1.0 microg ml(-1); 95% CI -1.7, -0.31). The median elimination half-life of NFV observed during pregnancy was 3.7 h (range 1.4-6.6 h), compared with 5.2 (range 3.1-10.1 h) in the control group (mean difference -1.7; 95% CI -2.8, -0.51).

CONCLUSIONS

Our results indicate that women in the later stages of pregnancy may be exposed to subtherapeutic concentrations of NFV. Thus, adjustments in drug dosage or frequency of administration may be required.

Diagnosis of HIV infection in pregnancy: data from a national cohort of pregnant women with HIV in Italy

We analysed the characteristics of the pregnancies with a previously undetected HIV infection in a national observational study of pregnant women with HIV in Italy. In a total of 443 pregnancies with available date of HIV diagnosis, 118 were characterized by a previously undetected HIV infection (26.6%, 95% CI 22.5-30.8). The following factors were independently associated with this occurrence in a multivariate analysis (adjusted odds ratios; 95% CIs): foreign nationality (5.1, 2.8-9.3); no pre-conception counselling (35.9, 4.8-266.1); first pregnancy (2.1, 1.2-4.0); asymptomatic status (6.8, 1.5-30.6). Women with previously undetected infection started antiretroviral treatment significantly later during pregnancy (P < 0.001). Missed diagnosis was responsible for one case of transmission. A high rate of previously undetected HIV infection was observed. This suggests a good HIV detection during pregnancy, but also the need to reinforce HIV testing strategies among women of childbearing age. We identified some determinants which may be considered for intervention measures.

Virological and immunological outcomes at 3 years after starting antiretroviral therapy with regimens containing non-nucleoside reverse transcriptase inhibitor, protease inhibitor, or both in INITIO: open-label randomised trial

BACKGROUND

Antiretroviral therapy has greatly reduced HIV mortality and morbidity. However, the best sequence of regimens and implications of initial regimen for long-term therapeutic success are not well defined.

METHODS

In INITIO, a large international randomised trial, we compared antiretroviral therapy with two nucleoside analogue reverse transcriptase inhibitors (didanosine+stavudine) plus either a non-nucleoside reverse transcriptase inhibitor (efavirenz, EFV) or a protease inhibitor (nelfinavir, NFV), or both (EFV/NFV), in patients with HIV-1 infection who had not previously received antiretroviral drugs. Primary outcomes were proportion with undetectable HIV RNA in plasma, and change in CD4 count from baseline at 3 years. Analyses were by intention-to-treat. This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN44582462.

FINDINGS

We followed up 911 participants (297 EFV, 311 NFV, 303 EFV/NFV). At 3 years, the proportion with HIV RNA less than 50 copies per mL was highest in the EFV group (188 [74%] EFV, 162 [62%] NFV, 155 [62%] EFV/NFV; p=0.004). Mean (95% CI) increases in CD4 count were 316x10(6) cells per L (288-343) for EFV, 289x10(6) cells per L (262-316) for NFV, and 274x10(6) cells per L (231-291) for EFV/NFV (p=0.1). Fewer participants in the EFV group than in the other groups stopped adequate antiretroviral therapy for more than 30 days (p=0.005). Participants in the EFV/NFV group had shorter time to stopping the initial regimen (p<0.0001) and to a treatment modifying adverse event (p=0.04) than those in the other groups.

INTERPRETATION

Starting antiretroviral therapy with a three-drug/two-class regimen including efavirenz was better than starting with regimens including nelfinavir or efavirenz plus nelfinavir in terms of virological suppression and durability of the initial regimen. The shorter time on adequate antiretroviral therapy or to a treatment-modifying adverse event might explain the absence of additional benefit for the four-drug regimen.

Risk factors and occurrence of rash in HIV-positive patients not receiving nonnucleoside reverse transcriptase inhibitor: data from a randomized study evaluating use of protease inhibitors in nucleoside-experienced patients with very low CD4 levels (<50 cells/mmuL)

BACKGROUND

Most of the studies evaluating rash in HIV-positive patients have focused on nonnucleoside reverse transcriptase inhibitors (NNRTI), particularly nevirapine, and little is known about the occurrence of rash and the risk factors for its development in patients receiving regimens not based on NNRTI.

METHODS

We evaluated all cases of rash observed during a 48-week randomized multicentre trial in 1251 nucleoside-experienced patients who started treatment with protease inhibitors (ritonavir or indinavir) at CD4 counts below 50 cells/microL. Incidence rates for rash were calculated according to gender, clinical status, age, use of highly active antiretroviral therapy (HAART), Pneumocystis carinii pneumonia (PCP) prophylaxis and use of individual antiretroviral drugs at enrollment. Differences between groups defined according to the above characteristics were tested for statistical significance using the log-rank test in a Kaplan-Meier survival analysis. All factors that gave results in the univariate analyses below the significance level of 0.05 were included in a multivariate analysis using a Cox regression model.

RESULTS

During a follow-up period of 9690 person-months, 66 patients (5.3%) developed rash (0.68 events/100 person-months). In the univariate analyses, risk of rash did not differ with trial treatment (indinavir or ritonavir), clinical status, PCP prophylaxis, or age. During follow-up, rash was observed in 7.5% of enrolled women and in 4.5% of enrolled men (P=0.03). Serious rash occurred in 4.5% of enrolled women and in 1.6% of enrolled men (P=0.003). Use of HAART (P<0.001) and inclusion of zidovudine and of zalcitabine in the prescribed regimen (P=0.02) appeared to be associated with a lower risk of rash. In the multivariate analysis, the variables that remained significantly predictive of rash were gender (risk for women compared to men: 1.65, 95% confidence interval (CI): 1.00-2.72, P=0.048) and use of a non-HAART regimen (risk for non-HAART patients compared to HAART: 2.73, 95% CI: 1.49-5.02, P=0.001).

CONCLUSIONS

In our study, about 5% of HIV-positive patients who started treatment with protease inhibitors at very low CD4 counts developed rash, generally in the first few weeks after treatment. Risk was significantly higher in women and in patients who did not receive a HAART regimen. Our data indicate that women have a higher risk of rash than men, also with regimens that do not include NNRTI.

HIV-related morbidity and mortality in patients starting protease inhibitors in very advanced HIV disease (CD4 count of < 50 cells/microL): an analysis of 338 clinical events from a randomized clinical trial

BACKGROUND

AIDS defining events occur infrequently in the presence of CD4 counts above 200 cells/microL. It is, however, uncertain for most of the AIDS defining conditions whether this threshold can be considered equally safe in patients with a previously very low CD4 nadir.

METHODS

We evaluated in detail all the AIDS defining events observed during a 48-week clinical trial in 1251 nucleoside reverse transcriptase inhibitor-experienced patients who started protease inhibitors (PIs) at CD4 counts below 50 cells/microL. The type of event, immunological status at the moment of event and time between start of PI treatment and event occurrence were analysed cumulatively and by event type; event rates were calculated.

RESULTS

Concomitant data on CD4 counts were available for 338 AIDS defining events (81% of total events). Median time between start of treatment with PI and event was 94.5 days and median absolute CD4 value at the occurrence of event was 20 per microL. Only 14 events (in 12 patients) were observed above the threshold of 200 CD4 cells/microL. An analysis of the 67 deaths with concomitantly available CD4 counts (57%) showed a median CD4 count of 10 cells/microL, with only four deaths occurring in the presence of a CD4 count above 100 cells/microL.

CONCLUSIONS

Very few clinical AIDS defining conditions were observed in patients who start PIs at very low CD4 counts and with treatment restore absolute values in CD4 counts above 200 cells/microL. This threshold can therefore be considered a clinically effective goal of treatment with respect to occurrence of all AIDS defining conditions in patients starting PIs in very advanced HIV disease.

A randomized trial comparing the introduction of ritonavir or indinavir in 1251 nucleoside-experienced patients with advanced HIV infection

ISS-IP1, a multicenter, randomized, 48-week open trial, was designed to compare the introduction of ritonavir or indinavir in patients with previous nucleoside experience and CD4+ cell counts below 50/mm3. Concomitant antiretroviral treatment with nucleoside analogs was allowed. Primary efficacy measures were survival and time to a new AIDS-defining event or death, analyzed through the whole period of observation by the intention-to-treat approach. Primary toxicity measures were time to treatment discontinuation and adverse events, grade at least 3/serious, analyzed by an on-treatment approach. Evaluation-of efficacy also included CD4+ cell and RNA response. The trial enrolled 1251 patients in 5 months. At baseline, mean CD4+ cell count was about 20 cells/mm3 and mean HIV RNA copy number was 4.9 log10/ml in both groups. Overall, 402 patients in the ritonavir group and 250 patients in the indinavir group permanently discontinued the assigned treatment (relative risk, 1.96; 95% CI, 1.68-2.30; p = 0.0001), with most of this difference dependent on a higher number of discontinuation for adverse events in the ritonavir group. After a mean follow-up of 307 days (ritonavir, 304; indinavir, 309), 124 deaths (ritonavir, 61; indinavir, 63; relative risk, 0.96; 95% CI, 0.67-1.36; p = 0.80) and 330 new AIDS-defining events (ritonavir, 170; indinavir, 160; relative risk, 1.05; 95% CI, 0.85-1.31; p = 0.60) were observed. CD4+ cell counts increased in both groups in patients still receiving treatment, with about 100 cells gained by week 24 and 150 cells gained by week 48. Body weight also increased over time in both groups. Analysis of RNA response showed a decrease of 1.5 log10 or higher in both treatment groups. Overall, 400 patients in the ritonavir group and 338 patients in the indinavir group developed at least one grade 3/serious new adverse event during follow-up (relative risk, 1.48; 95% CI, 1.28-1.72; p = 0.0001). Favorable CD4+ cell and RNA responses at 24 and 48 weeks were observed in both groups of patients remaining on treatment. Indinavir showed slightly better effects in sustaining RNA, CD4+ cell, and body weight responses. Ritonavir and indinavir results were comparable in terms of clinical outcome (survival and AIDS-defining events).

Quality of life outcomes of combination zidovudine- didanosine-nevirapine and zidovudine-didanosine for antiretroviral-naive advanced HIV-infected patients

OBJECTIVES

To evaluate the quality of life outcomes in antiretroviral-naive patients randomized to zidovudine plus didanosine versus zidovudine plus didanosine plus nevirapine for treatment of advanced HIV disease (the Istituto Superiore di Sanità 047 trial).

DESIGN

A 48-week randomized, double-blind trial.

METHODS

Sixty patients were enrolled and evaluated over 24 weeks. Quality of life was assessed using a modified version of the Medical Outcomes Study-HIV Health Survey. For analysis, we calculated two summary scores reflecting the physical (PHS) and the mental (MHS) components of health.

RESULTS

Although the three-drug combination was superior at inducing immunologic and virologic responses, the two-drug regimen was superior for both PHS and MHS, especially at week 8 where differences were both statistically and clinically significant (5.8 and 9.2 points, respectively, P< 0.02 for both). Quality of life changes paralleled trends in body weight and Karnofsky performance status score.

CONCLUSION

Although a three-drug antiretroviral therapy regimen was superior in terms of short term virologic/immunologic response, the two-drug regimen was better in terms of quality of life. In general, triple therapy remains the most effective treatment option. However, quality of life assessments can yield results that may be discordant with and complementary to those obtained using conventional endpoints. Comparative trials should collect a comprehensive range of outcome measures, including patient-reported quality of life, in order to provide clinicians and patients with additional information that may influence treatment decisions.

Plasma HIV-1 copy number and in vitro infectivity of plasma prior to and during combination antiretroviral treatment

Some studies on untreated patients have shown a general correlation between plasma HIV copy number and plasma infectivity in in vitro models. Recent observations also indicate that HIV-RNA level is an important predictor of perinatal transmission and may also have a role in heterosexual transmission. To further analyse the correlation between HIV viral load and plasma infectivity, we studied the relationship between HIV-1 plasma copy number and plasma infectivity prior to and during treatment with antiretroviral combination regimens in HIV-1 infected adults. Plasma infectivity was assessed in vitro by coculture of plasma from HIV-positive patients with PHA-stimulated fresh PBMC from uninfected donors. A positive plasma isolation, in almost all cases (43/45) and irrespective of treatment status, was associated with an HIV viral load higher than 100000 copies per ml, with higher plasma HIV-1 RNA values in isolation-positive samples compared with isolation-negative samples (median values, 710000 vs. 37500 copies per ml, respectively). SI and NSI strains had similarly high viral load values (470000 vs. 790000 copies per ml), but CD4 counts were lower in the SI phenotype group. Our data indicate that low levels of viral load are only exceptionally associated with isolation from plasma in the in vitro model we used. This observation confirms indirectly the presence of an association between viral load and infectivity. The requisite of a high plasma viral load in order to obtain infectivity (i.e. positivity of HIV isolation from plasma) also seems maintained under antiretroviral treatment, adding confidence in the conclusion that reductions in viral load translate into reduction of plasma infectivity. Due to the extreme complexity of factors determining transmission, a very prudent interpretation of the results is essential when information from experimental studies has to be transferred to clinical situations requiring assessment of risks or clinical decisions.

Hospitalizations and costs of treatment for protease inhibitor-based regimens in patients with very advanced HIV-infection (CD4 < 50/mm(3))

PURPOSE

To describe the cost of hospitalization and treatment in patients with very advanced disease who tart different regimens based on a protease inhibitor (PI).

METHOD

An observational retrospective analysis was performed on data from a 48-week randomized, multicenter study. Analysis was based on a subgroup of centers that were geographically defined. Costs of ordinary hospital admissions and of antiretroviral treatment were considered. Incidence of hospitalization and number of days free from hospitalization during the period of observation were calculated. Cost and hospitalization measures were compared among patients receiving three different therapeutic regimens: only PI, PI plus one nucleoside, or PI plus two nucleosides. A multivariate analysis was used to assess cost differences, controlling for variables potentially able to influence outcome.

RESULTS

Overall, among 166 patients starting PI (PI plus two nucleosides, 71;PI plus one nucleoside, 65; only PI, 30), 162 ordinary hospital admissions were observed during about 1 year of follow-up. Monthly rates of admission per person and incidence of first hospitalization on 100 person-months showed a clear inverse relationship with the number of drugs comprising the baseline treatment regimen, with the lower rates for the triple therapy group (0.06 and 3.9, respectively), intermediate values for the dual therapy group (0.10 and 8.1, respectively), and higher rates for the PI monotherapy group (0.15 and 13.7, respectively). The average number of days free from hospitalization per month was 29.5 in the triple therapy group, 28.6 in the dual therapy group, and 27.9 in the monotherapy group. The results of cost analysis showed, despite higher cost of antiretroviral treatment, that global costs were progressively lower using regimens of increasing potency: Compared to PI monotherapy, global cost (costs of antiretroviral treatment and of hospitalizations combined) per month per patient was 31.9% lower for the triple therapy group and 19.3% lower for the dual therapy. Global cost for the triple therapy was 15.7% lower compared to global cost for dual therapy. After adjustment for CD4 count, AIDS status, and Karnofsky score, both hospitalization costs and global costs were significantly lower for triple therapy compared to monotherapy (p =.002 and.039, respectively).

CONCLUSION

In advanced and nucleoside-experienced patients, PI-containing regimens have a differential impact according to the overall strength of the regimen, with the best effects on both hospitalizations and treatment costs obtained using PI within potent combination regimens.

Prevalence and characteristics of multinucleoside-resistant human immunodeficiency virus type 1 among European patients receiving combinations of nucleoside analogues

The prevalence and the genotypic and phenotypic characteristics of multinucleoside-resistant (MNR) human immunodeficiency virus type 1 (HIV-1) variants in Europe were investigated in a multicenter study that involved centers in nine European countries. Study samples (n = 363) collected between 1991 and 1997 from patients exposed to two or more nucleoside analogue reverse transcriptase inhibitors (NRTIs) and 274 control samples from patients exposed to no or one NRTI were screened for two marker mutations of multinucleoside resistance (the Q151M mutation and a mutation with a 2-amino-acid insertion at codon 69, T69S-XX). Q151M was identified in six of the study samples (1. 6%), and T69S-XX was identified in two of the study samples (0.5%; both of them T69S-SS), but both patterns were absent among control samples. Non-NRTI (NNRTI)-related changes were observed in viral strains from two patients, which displayed the Q151M resistance pattern, although the patients were NNRTI naive. The patients whose isolates displayed multinucleoside resistance had received treatment with zidovudine and either didanosine, zalcitabine, or stavudine. Both resistance patterns conferred broad cross-resistance to NRTIs in vitro and a poor response to treatment in vivo. MNR HIV-1 is found only among multinucleoside-experienced patients. Its prevalence is low in Europe, but it should be closely monitored since it seriously limits treatment options.

A randomized, double-blind trial on the use of a triple combination including nevirapine, a nonnucleoside reverse transcriptase HIV inhibitor, in antiretroviral-naive patients with advanced disease

The immunologic and virologic activity of nevirapine in combination with two nucleosides (zidovudine [ZDV] and didanosine [ddI]) was evaluated in antiretroviral-naive patients with a CD4 count <200/mm3 or clinical AIDS. In all, 68 patients were enrolled in a 48-week double-blind, placebo-controlled trial. A group of 32 patients received ZDV + ddI + nevirapine, and 36 patients received ZDV + ddI. Primary efficacy parameters were the activity on HIV-1 RNA and on peripheral blood CD4+ cells, with differences between groups analyzed by the Wilcoxon's nonparametric two-sample test. Baseline RNA was high in both treatment groups (median values, 5.8 and 5.7 log10). RNA and CD4 responses were significantly higher with the triple combination (median RNA reductions, 2.69 versus 1.05 log10 at 24 weeks and 1.97 versus 1.20 log10 at 48 weeks; median CD4 increases, 81 versus 64 cells/mm3 at 24 weeks and 101 versus 27 cells/mm3 at 48 weeks). This study demonstrates that a triple combination of ZDV + ddI + nevirapine used as first-line regimen in antiretroviral-naive patients can induce sustained virologic and immunologic response in patients with low CD4 count or a previous diagnosis of AIDS.

Saquinavir. Clinical pharmacology and efficacy

Saquinavir is an HIV protease inhibitor with no, or limited, effect on the activity of other structurally related human aspartic proteinases. As with other HIV protease inhibitors, saquinavir inhibits the cleavage of the gag-pol protein substrate leading to the release of structurally defective and functionally inactive viral particles. It is active on both HIV-1 and HIV-2, and also has activity on chronically infected cells and HIV strains resistant to reverse transcriptase inhibitors. Synergy of action has been observed with other antiretroviral drugs. Saquinavir is characterised by a low bioavailability which is further reduced in the fasting state. Metabolism is mainly hepatic through cytochrome P450 (CYP) 3A4, but intestinal metabolism through the same system has also been reported. To achieve higher drug plasma concentrations and increase the antiviral effect, a new formulation of saquinavir with a higher bioavailability has recently been introduced. Higher plasma drug concentrations may also be obtained by combining the drug with CYP blockers, such as ritonavir or ketoconazole. Because of its metabolic interference with the CYP system, saquinavir cannot be coadministered with astemizole, terfenadine or cisapride. Rifampicin (rifampin) is also contraindicated because coadministration can lead to decreases in saquinavir concentrations. Interactions have also been reported with other drugs metabolised through the same system, including non-nucleoside reverse transcriptase inhibitors and HIV protease inhibitors. Resistance has been observed after both in vitro and in vivo drug exposure, with a relatively specific mutation profile compared with other protease inhibitors. Saquinavir is generally well tolerated, with mild gastrointestinal symptoms representing the most commonly observed adverse effects. Although characterized by low bioavailability, in phase III trials saquinavir has been shown to have clinical efficacy in terms of survival and progression rate. As with the other protease inhibitors, saquinavir should be used in combination with other antiretroviral drugs. Current therapeutic guidelines, however, recommend the selection of an initial treatment regimen with other protease inhibitors with higher in vivo activity in terms of RNA and CD4 response. The results of ongoing studies will clarify to what extent a new saquinavir formulation, recently introduced, is superior to the previous one in terms of antiviral activity and to provide comparisons with other protease inhibitors. Further studies are also needed to define the best place of saquinavir within treatment strategies based on protease inhibitors, particularly in respect to the optimal sequence for its use with other protease inhibitors, and the dynamics of cross-resistance and its role within regimens based on the combination of protease inhibitors.

A randomized trial (ISS 902) of didanosine versus zidovudine in previously untreated patients with mildly symptomatic human immunodeficiency virus infection

In this multicenter study (ISS 902), 554 previously untreated patients with <500 CD4 cells/mm3 and mildly symptomatic human immunodeficiency virus disease were randomized to receive zidovudine or didanosine (ddI). After a mean follow-up of 20 months, 80 patients (40 zidovudine, 40 ddI) had died and 146 had at least one AIDS-defining event (73 zidovudine, 73 ddI). Overall, no difference was found between treatments with respect to progression to AIDS or death. The analysis of relative risk (RR) of progression over time, however, showed an initially minor risk for zidovudine patients and an inversion in the zidovudine-ddI RR in the second and third years of follow-up. Didanosine showed a greater effect on CD4 cell count response. The two drugs confirmed the toxicity patterns already reported in other trials, with a low occurrence of pancreatitis (ddI 1.3%, zidovudine 0.4%). The overall results suggest that, in this population, zidovudine and ddI monotherapies have comparable long-term clinical efficacy and that more powerful regimens should be preferred.

AIDS dementia complex in the Italian National AIDS Registry: temporal trends (1987-93) and differential incidence according to mode of transmission of HIV-1 infection

OBJECTIVES

To investigate the occurrence of AIDS dementia complex (ADC) in Italy and its incidence over time, examining possible correlations between this condition and some demographic and immunological variables.

DESIGN

Inception cohort. Data collected from the case notification forms of the Italian National AIDS Registry.

SUBJECTS

16813 consecutive AIDS cases reported to the National AIDS Registry from August 1, 1987 through October 31, 1993 were included.

STATISTICAL METHODS

All data refer to the time of AIDS diagnosis as reported on the case notification forms. Main analyses of the monthly proportion of ADC cases were by multiple logistic regression.

RESULTS

1364 subjects (8.1%) were reported with a diagnosis of ADC as the first AIDS defining disease, either as the only manifestation or associated with other AIDS defining conditions. At the time of AIDS diagnosis, the observed ADC/AIDS proportion was significantly higher among intravenous drug users (IVDU), 9.1%, compared to heterosexuals, 6.3%, and homo-bisexual men, 5.2%. Simple logistic regression analysis showed a significant (p < 0.0001) quadratic trend in the monthly ADC/AIDS proportion, peaking in March 1990 and decreasing thereafter. Multiple logistic regression, adjusting for month of diagnosis, showed that IVDUs have consistently the highest risk and homo-bisexual men the lowest, although differences tended to decrease with increasing age. Older age, in fact, was highly associated with an increased risk, especially within the homo-bisexual and heterosexual transmission categories. CD4 + cells counts proved to have no significant effect on the risk of progressing to AIDS with ADC rather than with any other AIDS indicative disease.

CONCLUSIONS

ADC is a relatively frequent manifestation at diagnosis of AIDS among Italian patients, and particularly in IVDUs. Differences in its occurrence were found according to time of diagnosis, transmission category and age.

A randomized trial (ISS 901) of switching to didanosine versus continued zidovudine after the diagnosis of AIDS

Although the efficacy of switching from zidovudine (AZT) to didanosine (ddI) has already been evaluated in controlled studies, prior investigations were not specifically designed to evaluate this issue in patients with acquired immune deficiency syndrome (AIDS). This open, randomized, multicenter study (ISS 901) was designed to evaluate the clinical benefit in patients with AIDS of switching to ddI after 6-18 months of AZT and no major intolerance. Patients were randomized to continue AZT, maintaining the current dosage at randomization (n = 79), or to receive ddI (n = 80) at the dosage of 375 mg and 250 mg b.i.d. for body weight > 60 and < or = 60 kg, respectively. Primary efficacy measures were survival and time to new AIDS-defining events, analyzed by the intent-to-treat approach. The two groups were comparable for baseline characteristics, follow-up (15 months), and time spent on allocated treatment. At the end of the study, 104 patients (48 AZT, 56 ddI) had died and 90 had at least one new AIDS-defining event (44 AZT, 46 ddI). Kaplan-Meier estimates of survival and of time to first new AIDS-defining event showed no differences between the treatment groups. No differences were detected in other efficacy measurements (p24 antigenemia, CD4+ count, Karnofsky score, and body weight), occurrence of severe toxicities, and treatment modifications. Pancreatitis occurred only in ddI-treated patients (6%). In our population of patients with advanced disease, switching from AZT to ddI did not produce apparent benefits, suggesting that application of this strategy earlier in the course of human immunodeficiency virus disease should be considered.

A randomized controlled trial of a protease inhibitor (saquinavir) in combination with zidovudine in previously untreated patients with advanced HIV infection

This study assessed the activity and tolerability of an HIV-protease inhibitor, saquinavir, alone or in combination with zidovudine. A total of 92 previously untreated HIV-infected patients with CD4 cell counts < 300 cells/mm3 participated in a parallel, randomized double-blind study. Patients were randomized to receive one of five treatments, each three times a day: 600 mg of saquinavir; 200 mg of zidovudine; 75, 200 or 600 mg of saquinavir in combination with 200 mg of zidovudine. The primary treatment period was 16 weeks, with monthly extensions in patients who did not show major disease progression or toxicity. The main measures of the efficacy of therapy used were changes in CD4 cell counts and in the concentration of HIV-1 RNA in the plasma (as determined by quantitative polymerase chain reaction). The 600 mg dose of saquinavir in combination with zidovudine induced a 1.6 log (after 4 weeks) and a 0.7 log (after 16 weeks) median reduction in plasma RNA concentration; this reduction was greater than those seen in the other four treatment groups. The combination of 600 mg of saquinavir with zidovudine also resulted in a larger and more sustained improvement in the CD4 cell count than either saquinavir or zidovudine monotherapy or the other combination therapies. In the group receiving 200 mg of saquinavir in combination with zidovudine, the maximal median change in CD4 cell count occurred at week 2 (85 cells/mm3), and by week 16 had fallen to 15 cells/mm3. In the group receiving 600 mg of saquinavir plus zidovudine, the median change in CD4 cell count remained high for the 16-week period (median change of 48 cells/mm3 at week 2 and 61 cells/mm3 at week 16). Saquinavir was safe and very well tolerated, either alone or in combination with zidovudine. The incidence of adverse events was greater in the four groups receiving zidovudine therapy, and all the most commonly reported adverse events have previously been associated with zidovudine therapy. Few changes in laboratory values occurred during the study, except for known zidovudine-associated toxicities. The most frequent abnormalities were raised aspartate aminotransferase and alanine aminotransferase levels, depressed calcium levels, and abnormally high or low phosphate levels. Despite the low oral bioavailability of saquinavir, combined virological and immunological data show definite antiviral activity in vivo for the combination of saquinavir at 600 mg plus zidovudine at 200 mg (each three times daily). The combination of drugs with different mechanisms of action represents an advance in the treatment of HIV infection.

Effect of sex, age and transmission category on the progression to AIDS and survival of zidovudine-treated symptomatic patients

OBJECTIVE

To evaluate the effect of transmission category and demographic, clinical and immunological characteristics on the progression to AIDS and survival of zidovudine-treated patients.

DESIGN

Prospective multicentre cohort study of symptomatic non-AIDS patients.

SETTING

Eighty-three clinical centres reporting data to the National Zidovudine Registry.

PATIENTS

A total of 1468 patients enrolled between July 1987 and January 1991 were analysed.

MAIN OUTCOME MEASURES

Three-year AIDS-free survival probability estimates since therapy start. Cox proportional hazards regression analysis was used to identify independent predictors of progression to AIDS and survival.

RESULTS

Faster progression was associated with increasing age (8% risk increase for a 5-year increase), low baseline CD4+ count (39% risk increase for 100 x 10(6)/l cells decrease), and zidovudine > 1000 mg/day (20% risk increase compared with < or = 1000 mg/day). Homosexual men had a 33% risk increase compared with other risk groups. The presence of fever and oral candidiasis at enrolment were also independently associated with a higher risk of progression. Differences in the risk of progression were not significant between men and women. Older age, baseline CD4+ count, homosexual behaviour, fever and oral candidiasis were independently associated with a shorter survival.

CONCLUSIONS

Our results confirm that age and baseline CD4+ count are independent predictors of progression, but do not provide evidence for differences in clinical outcome between the sexes. The higher risk of progression to AIDS and shorter survival for homosexual men appears to be correlated with the higher risk of developing Kaposi's sarcoma.

Differential survival of patients with AIDS according to the 1987 and 1993 CDC case definitions

OBJECTIVE

To evaluate the impact of the 1993 Centers for Disease Control and Prevention (CDC) revised classification system for human immunodeficiency virus and expanded surveillance case definition for acquired immunodeficiency syndrome (AIDS) on the number of cases and on survival of patients with AIDS.

DESIGN

Retrospective analysis of data from a prospective cohort study of patients treated with zidovudine.

PATIENTS

A total of 3515 patients enrolled in the Italian National Registry of Zidovudine-Treated Patients between July 1987 and December 1991 were analyzed.

MAIN OUTCOME MEASURES

Numbers and survival probability estimates (using the Kaplan-Meier method) for patients satisfying the 1993 CDC case definition compared with patients fulfilling the 1987 CDC classification. Multiple regression analysis was also used to analyze the combined effect of independent variables on survival.

RESULTS

According to the new classification system, the number of AIDS cases in the study population would increase by 188%. While the median survival of patients meeting the 1987 definition was 24 months, at the end of 57 months 53% of patients meeting the 1993 definition were still alive. Among the patients meeting the laboratory criteria for AIDS diagnosis using the new definition (CD4+ lymphocyte count < 0.20 x 10(9)/L [200/microL]), the presence of an AIDS-defining illness was a strong independent predictor of death.

CONCLUSIONS

The application of the new definition results in a considerable increase in the number of cases. Survival for patients classified according to the 1993 definition is much longer than for those classified with the 1987 definition. Clinical status plays a major role in predicting survival outcome among patients whose CD4+ lymphocyte counts meet the new case definition.

Long-term follow-up of zidovudine therapy in asymptomatic HIV infection: results of a multicenter cohort study. The Italian Zidovudine Evaluation Group

In 1990 the results of a placebo-controlled study conducted within the AIDS Clinical Trials Group (ACTG 019) showed that in the short term, zidovudine was effective in slowing progression to advanced disease in HIV-infected asymptomatic patients with low CD4 cell counts. More recently, the preliminary results of the Concorde Trial suggested that while the data at 1 year agreed with those of ACTG 019, no sustained clinical benefit was detectable at 3 years for early versus deferred therapy. Therefore, the length of the clinical usefulness of zidovudine in this population is still to be determined. We evaluated the 2-year outcome of zidovudine therapy in asymptomatic patients through the prospective follow-up of a cohort of 936 subjects with low CD4+ (< 500/mm3) counts who strictly satisfied, at enrollment, the inclusion and exclusion criteria of the ACTG 019 trial. The clinical end point of the analysis was the development of AIDS. The majority (72.2%) of the individuals in the cohort acquired HIV infection through intravenous drug use; 26.6% were women. The median baseline CD4 cell count was 308/mm3. At 55 weeks of mean follow-up, the progression rate to AIDS (3.2 events per hundred person-years) appears to be comparable to that already reported at the same mean follow-up time for the ACTG 019 zidovudine-treated asymptomatic patients. After 124 weeks of mean follow-up, the overall rate of progression to AIDS was 5.2 per hundred person-years.(ABSTRACT TRUNCATED AT 250 WORDS)

The effects of AZT and DDI on pre- and postimplantation mammalian embryos: an in vivo and in vitro study

This study reports the effects of the nucleoside analogs dideoxyinosine (DDI) and 3'-azido-3'-deoxythymidine (AZT) on mammalian embryonic development. When administered to pregnant mice (at concentrations ranging from 10 to 300 mg/kg/day), through all or part of gestation, AZT and DDI did not result in any visible effect on mouse embryos nor did they cause any obvious malformation or defect at birth or during postnatal growth. Similarly, when embryonic or fetal mouse or human cells (from brain, limb buds, or different organ rudiments) were exposed to AZT or DDI in vitro, cytotoxicity was observed only in the mM range, with AZT showing slightly higher cytotoxicity and brain cells appearing slightly more sensitive to both nucleosides. However, even in cultures treated with very high concentrations of AZT or DDI, the reduction in the number of terminally differentiated skeletal myotubes, cardiocytes, neurons, and chondrocytes was similar to the reduction in the total number of cells, indicating that AZT and DDI did not selectively inhibit differentiation of any of the above-mentioned cell types. Finally, preimplantation mouse embryos (at the 2-cell or 4-cell stage), treated in vitro with micromolar concentrations of AZT, were arrested at the 4-cell stage. DDI or other nucleoside analogs tested did not have this effect.

Survival of zidovudine-treated patients with AIDS compared with that of contemporary untreated patients. Italian Zidovudine Evaluation Group

OBJECTIVE

To assess the long-term effectiveness of zidovudine (AZT) in patients with acquired immunodeficiency syndrome (AIDS). This assessment has never been adequately done because controlled clinical trials were stopped early and survival comparisons were made with historical controls.

DESIGN

Nonrandomized contemporary observational study of patients treated and not treated with zidovudine.

SETTING

Twenty-three AIDS treatment centers throughout Italy that reported cases to the National Registry of AIDS Cases between July 1987 and March 1988.

PATIENTS

One hundred fifty-nine zidovudine-treated and 112 untreated patients with AIDS, the majority of whom had acquired human immunodeficiency virus (HIV) infection through intravenous drug use.

OUTCOME MEASURES

Median survival and 1- and 2-year survival for treated and untreated groups, as estimated using the Kaplan-Meier method. Cox proportional hazards regression analysis was also used to identify independent predictors of survival among the variables studied.

RESULTS

Patients were similar with respect to CD4/CD8 ratio, age, sex, clinical and immunological status at diagnosis, and source of HIV infection. After 24 months, survival was 45.9% (95% confidence interval [CI], 36.1% to 55.7%) in the treated group and 20.5% (95% CI, 12.6% to 28.3%) in the untreated group, with median survival of 21.2 and 9.6 months, respectively.

CONCLUSIONS

Possible biases of this study include imperfect matching for clinical status and better overall medical care of treated patients. Nevertheless, we believe that the observed differences in survival were primarily due to zidovudine treatment.