Antiretroviral therapy in children: Indian experience

BACKGROUND

There is a paucity of reports on Highly Active Antiretroviral therapy (HAART) in children. We studied feasibility and effectiveness fixed dose combination (FDC) of lamivudine, nevirapine and stavudine in HIV infected children.

DESIGN

Interventional study.

SETTING

A Tertiary care center.

SUBJECTS

Twenty five consecutive HIV positive antiretroviral naive children older than 18 months.

METHODS

The study subjects were started on weight-appropriate doses of the FDC and followed up for 6 months. Weight, CD4 counts, absolute lymphocyte count (ALC) and number of episodes of illness were assessed before and after HAART. Adherence and barriers to adherence were studied.

RESULTS

Mean weight increased from 15.2 to 16.8 kg (P < 0.001) while mean CD4 counts increased from 488/cmm to 765/cmm (P < 0.001). Only 2 cases of drug associated adverse event were encountered. Improvement in Center for Disease Control (CDC) immunological classification of the subjects was significant while that in World Health Organization (WHO) clinical staging was not statistically significant. Follow up visits were 95% of the expected 175 visits. The average distance traveled by the patient for every visit was 72 km (one way).

CONCLUSIONS

Use of FDC in weight specific dosages is feasible and effective for treatment of Pediatric HIV in resource scarce setting. These preliminary results need to be tested in a different setting.

Systematic review of clinical trials evaluating low doses of stavudine as part of antiretroviral treatment

Stavudine is a nucleoside analogue used for the treatment of HIV-1 infection, as part of highly active antiretroviral treatment. In developing countries, stavudine is used widely, owing to low cost and inclusion in generic fixed-dose combinations. In developed countries, stavudine is now rarely used, although it is highly effective. This is because newer drugs show lower rates of mitochondrial toxicities, such as lipoatrophy, peripheral neuropathy and lactic acidosis. In the development of stavudine, there was evidence that a dosage of 20-30 mg b.i.d. was effective, but the 40-mg b.i.d. dose gained regulatory approval. This review analyses the clinical trials conducted before and after the regulatory approval of stavudine, and shows that the dose of 30 mg b.i.d. has equivalent antiviral efficacy (given the caveats of meta-analysis), with some evidence of lower rates of peripheral neuropathy and lipoatrophy. With limited resources for HIV-1 treatment in developing countries, and only 25% of eligible patients receiving highly active antiretroviral treatment, low-cost treatment options such as stavudine still need to be pursued, if safety can be improved by dose optimisation.

Triple antiretroviral prophylaxis administered during pregnancy and after delivery significantly reduces breast milk viral load: a study within the Drug Resource Enhancement Against AIDS and Malnutrition Program

BACKGROUND

The administration of antiretroviral therapy to lactating women could represent a possible strategy to reduce postnatal HIV transmission. In this study, we assessed the effect of antiretroviral treatment on breast milk viral load and determined plasma and breast milk drug concentrations in pregnant women receiving highly active antiretroviral therapy (HAART).

METHODS

We studied 40 women receiving zidovudine, lamivudine, and nevirapine from 28 weeks of gestation to 1 month postpartum (group A) and 40 untreated pregnant women (group B). Blood and breast milk samples were collected at delivery and 7 days postpartum.

RESULTS

Women in group A had received a median of 85 days of therapy before delivery. Median breast milk concentrations of nevirapine, lamivudine, and zidovudine were 0.6, 1.8, and 1.1 times, respectively, those in maternal plasma. HIV RNA levels in breast milk were significantly lower in group A than in group B (median of 2.3 vs. 3.4 log at delivery and 1.9 vs. 3.6 log at day 7; P < 0.001 for both comparisons).

CONCLUSIONS

Antiretroviral drugs administered during the last trimester of pregnancy and after delivery reach levels similar to or higher than plasma concentrations in breast milk and can significantly reduce HIV RNA levels. Our data support the potential role of maternal HAART prophylaxis in reducing the risk of breast-feeding-associated transmission.

Relation of stavudine discontinuation to anthropometric changes among HIV-infected women

OBJECTIVE

To characterize changes in regional anthropometry associated with stavudine exposure and discontinuation.

DESIGN

Seven hundred thirty-four HIV-infected participants who reported using stavudine (574 of whom later discontinued stavudine) and 698 HIV-uninfected participants from the Women's Interagency HIV Study provided anthropometrics at 8706 semiannual visits between July 1999 and March 2005.

METHODS

Changes in weight, waist, chest, upper arm, hip, and midthigh circumferences were evaluated using linear regression with generalized estimating equations.

RESULTS

HIV-uninfected women demonstrated increases in regional anthropometry at every body site, whereas HIV-infected women demonstrated decreases in weight and circumferences of the waist, chest, hip, and thigh. A smaller annual decrease in hip circumference was seen after discontinuing stavudine for >2.25 years compared with the decrease observed while on stavudine (P = 0.01). Discontinuing stavudine for >2.25 years was associated with smaller (P < 0.05) decreases in hip (-0.06 cm/y) and thigh (-0.005 cm/y) circumference compared with the decreases observed between 1 and 2.25 years (hip: -0.46 cm/y, thigh: -0.24 cm/y) or < or =1 year (hip: -0.64 cm/y, thigh: -0.27 cm/y) after stavudine discontinuation.

CONCLUSIONS

Regardless of continuing or discontinuing stavudine, HIV-infected women demonstrate decreases in weight and body circumference measurements over time. The lower limb seems to be most affected by stavudine exposure, with stabilization observed more than 2 years after discontinuation.

Evaluation of Human Immunodeficiency Virus Type 1-Infected Chinese Patients Treated with Highly Active Antiretroviral Therapy for Two Years

The purpose of this study was to evaluate the long-term efficacy and safety of nevirapine in combination with didanosine and stavudine in the treatment of human immunodeficiency virus (HIV)1-infected Chinese patients in routine clinical practice. The study, from April 2003 to May 2005, with follow-up through 24 mo, was conducted at the Department of Infectious Diseases, Second Xiangya Hospital, Central-South University in Changsha, Hunan Province, China. Twenty-seven HIV1-infected patients received didanosine, stavudine, and nevirapine. Information from case notes regarding age, sex, side effects, viral load, naive and memory T cells, and CD4(+) and CD8(+) T cell count at baseline, 3, 6, 12, 18, and 24 mo was collected and analyzed. Virologic suppression, defined as an HIV RNA concentration of less than 50 copies/mL at months 3, 6, 12, 18, and 24, was considered the main outcome measure. Of 27 patients, 17 were men with a mean age 33.5 yr. The mean baseline viral load was 5.15 log copies/mL and the mean CD4(+) cell count was 185 cells/dL. Of 27 patients, 3 patients discontinued study medication; treatment was changed, because of side effects, from didanosine (ddI), stavudine (d4T), and nevirapine (NVP) to zidovudine, lamivudine, and NVP for 24 patients who had completed 24 mo of treatment with ddI, d4T, and NVP; and viral load suppression was attained in 17 patients (70.8%) at 12 mo, in 14 patients (58.3%) at 18 mo, and in 13 patients (56.6%) at 24 mo. The CD4 T cell count increased by 114 cells/microL (mean, 299 cells/microL) after 12 mo of treatment and by 132 cells/microL (mean, 317 cells/microL) after 24 mo of treatment. Naive T cells and memory cells also increased in number, but at a slower rate. Activated (CD38(+)) CD8(+) T cells were elevated at baseline (67.7%) and declined by month 24 (49.7%), but did not reach normal levels. We conclude that a regimen of NVP with ddI and d4T provided durable suppression of plasma viral load in HIV-infected patients, with significant improvement in the CD4 cell count, and can be well tolerated by patients with HIV-1 infection.

Plasma nevirapine levels and 24-week efficacy of a fixed-dose combination of stavudine, lamivudine and nevirapine (GPO-VIR) among Thai HIV-infected patients

BACKGROUND

A fixed-dose combination of stavudine, lamivudine, and nevirapine (GPO-VIR) is the most affordable antiretroviral therapy (ART) regimen in Thailand. The data of nevirapine (NVP) level and efficacy of this fixed-dose combination is limited.

MATERIAL AND METHOD

Patients who were initiated GPO-VIR in 2004 were enrolled NVP levels at 12 weeks were determined. Patients were followed for 24 weeks.

RESULTS

Fifty-nine patients with a mean age of 36.4 years and 54% male were enrolled. Mean body weight was 54.7 kgs. Median baseline CD4 and HIV-RNA were 29 cells/mm3 and 270,000 (5.4 log10) copies/mL, respectively. Mean plasma NVP levels at 12 weeks was 6.4 mg/L. By linear regression, female gender (p = 0.042), and higher weight (p = 0.020) were associated with lower NVP levels. At 24 weeks, 78% achieved undetectable HIV-RNA and median CD4 was 156 cells/mm3.

CONCLUSION

NVP levels and 24-week efficacy of GPO-VIR are favorable. According to the affordable cost, GPO-VIR should be an appropriate initial regimen for naïve HIV-infected patients in resource-limited settings.

Efficacy of a generic fixed-dose combination of stavudine, lamivudine and nevirapine (GPO-VIR) in Thai HIV-infected patients

BACKGROUND

GPO-VIR, fixed-dose combination of stavudine 30/40 mg, lamivudine 150 mg, and nevirapine 200 mg are widely used in Thailand.

OBJECTIVE

Determine the efficacy and tolerability of GPO-VIR in naive HIV-infected patients.

MATERIAL AND METHOD

Primary outcome was the time of initiation to achieve the goal of therapy, which was HIV RNA < 50 copies/mL or 50% increased of CD4 cell count. Ninety patients were eligible for the present study. Mean +/- SD age was 35 +/- 7 years and 51% were male. Median baseline CD4 and HIV RNA were 52 cells/ mm3 and 280,000 (5.4 log10) copies/mL, respectively. Sixty-two (69%) patients had previous opportunistic infections.

RESULTS

In a median follow-up period of 15 weeks, 49 (54%) patients achieved the goal of therapy. The probability of goal achievement showed that 12-, 24-, 36- and 48- weeks success rates were 8.5% [95% confidence interval (CI): 3.9-18.0%], 62.7% (95% CI: 50.8-74.6%), 80.0% (95% CI: 67.3-90.1%), and 93.3% (95% CI: 76.3-99.4%), respectively. The median success time to achieve the goal was 21 weeks. Eleven (12%) patients needed to discontinue GPO-VIR because of adverse drugs reaction.

CONCLUSION

GPO-VIR may be one of the antiretroviral regimens for HIV-infected patients in Thailand and other resource-limited countries. Its efficacy is good in patients with advanced HIV infection.

Severity of the toxicity associated with combinations that include didanosine plus stavudine in HIV-infected experienced patients

BACKGROUND

The combination of didanosine (ddI) and stavudine (d4T) is no longer recommended as a first-line treatment because of toxicity, but it may be useful in experienced patients.

METHODS

Retrospective chart review of experienced patients on ddI plus d4T was conducted at a single institution, recording the development of adverse events as well as their severity and action taken. The risk of developing severe toxicities was estimated by Kaplan-Meier analysis.

RESULTS

A total of 616 patients were on ddI plus d4T for a median time of 12 months (interquartile range: 5.0-24.7 months). Among them, 213 (34.6%) had AIDS, 161 (27.4%) had CD4 counts <200 cells/mm, and 503 (81.2%) had >2 previous treatment failures. Adverse events related to ddI plus d4T were recorded in 136 patients (22.1%), which were mild to moderate in 118 (19.1%) patients and severe in 18 (2.9%) patients. The mean times to development of severe and nonsevere adverse events were 72 (95% confidence interval [CI]: 70 to 75) weeks and 52 (95% CI: 48 to 55) weeks, respectively. The probability of developing severe adverse events was related to the nadir CD4 count, with higher risk in patients with <200 cells/mm (log rank test, P = 0.045).

CONCLUSIONS

Multiexperienced patients treated with combinations, including ddI plus d4T, frequently develop drug-related toxicity, but these events are rarely severe. Thus, these drugs can still be considered a valid option for salvage regimens.

High doses of stavudine induce fat wasting and mild liver damage without impairing mitochondrial respiration in mice

OBJECTIVE

Stavudine (d4T), a nucleoside reverse-transcriptase inhibitor (NRTI), can induce lipoatrophy, fatty liver, hyperlactataemia and abnormal liver tests. NRTI toxicity is usually ascribed to mitochondrial DNA (mtDNA) depletion and impaired mitochondrial respiration. However, NRTIs could have effects unrelated to mtDNA. Recently, we reported that 100 mg/kg/day of d4T stimulated fatty acid oxidation (FAO) in mouse liver, and reduced body fatness without depleting white adipose tissue (WAT) mtDNA. We hypothesized that higher d4T doses could further reduce adiposity, while inhibiting hepatic FAO.

METHODS

Mice were treated for 2 weeks with d4T (500 mg/kg/day), L-carnitine (200 mg/kg/day) or both drugs concomitantly. Body fatness was assessed by dual energy X-ray absorptiometry, and investigations were performed in plasma, liver, muscle and WAT.

RESULTS

D4T reduced the gain of body adiposity, WAT leptin, whole body FAO and plasma ketone bodies, and increased liver triglycerides and plasma aminotransferases with mild ultrastructural abnormalities in hepatocytes. Plasma lactate and respiratory chain activities in tissues were unchanged. Stearoyl-CoA desaturase (SCD-1), an enzyme negatively regulated by leptin, was overexpressed in liver. High doses of beta-aminoisobutyric acid (BAIBA), a d4T catabolite, increased plasma ketone bodies. Although L-carnitine did not correct body adiposity, it prevented d4T-induced impairment of FAO and liver abnormalities.

CONCLUSIONS

D4T overdosage triggers fat wasting, leptin insufficiency and mild liver damage, without causing respiratory chain dysfunction. Overexpression of SCD-1 reduces fatty acid oxidation and overcomes the stimulating effect of BAIBA on hepatic FAO. L-carnitine does not correct leptin insufficiency but prevents d4T-induced impairment of FAO and liver damage.

Nevirapine concentrations in HIV-infected children treated with divided fixed-dose combination antiretroviral tablets in Malawi and Zambia

OBJECTIVE

To investigate nevirapine concentrations in African HIV-infected children receiving divided Triomune tablets (stavudine+lamivudine+nevirapine).

DESIGN

Cross-sectional study.

METHODS

Steady-state plasma nevirapine concentrations were determined in Malawian and Zambian children aged 8 months to 18 years receiving Triomune in routine outpatient settings. Predictors from height-for-age, body mass index (BMI)-for-age, age, sex, post-dose sampling time and dose/m2/day were investigated using centre-stratified regression with backwards elimination (P<0.1).

RESULTS

Of the 71 Malawian and 56 Zambian children (median age 8.4 vs 8.5 years, height-for-age -3.15 vs -1.84, respectively), only 1 (3%) of those prescribed > or =300 mg/m2/day nevirapine had subtherapeutic concentrations (<3 mg/l) compared with 22 (23%) of those prescribed <300 mg/m2/day; most children with subtherapeutic nevirapine concentrations were taking half or quarter Triomune tablets. Lower nevirapine concentrations were independently associated with lower height-for-age (indicating stunting) (0.37 mg/l per unit higher [95% confidence interval (CI): -0.003, +0.74]; P=0.05), lower prescribed dose/m2 (+0.89 mg/l per 50 mg/m2 higher [95% CI: 0.32, 1.46]; P=0.002) and higher BMI-for-age (indicating lack of wasting) (-0.42 mg/l per unit higher [95% CI: -0.80, -0.04]; P=0.03).

CONCLUSIONS

Currently available adult fixed-dose combination tablets are not well suited to children, particularly at younger ages: Triomune 30 is preferable to Triomune 40 because of the higher dose of nevirapine relative to stavudine. Further research is required to confirm that concentrations are reduced in stunted children but increased in wasted children. Development of appropriate paediatric fixed-dose combination tablets is essential if antiretroviral therapy is to be made widely available to children in resource-limited settings.

Experience with the use of a first-line regimen of stavudine, lamivudine and nevirapine in patients in the TREAT Asia HIV Observational Database

BACKGROUND

The antiretroviral treatment (ART) combination of stavudine, lamivudine and nevirapine (d4T/3TC/NVP) is the most frequently used initial regimen in many Asian countries. There are few data on the outcome of this treatment in clinic cohorts in this region.

METHODS

We selected patients from the TREAT Asia HIV Observational Database (TAHOD) who started their first ART regimen with d4T/3TC/NVP. Treatment change was defined as cessation of therapy or the addition or change of one or more drugs. Clinical failure was defined as diagnosis with an AIDS-defining illness, or death while on d4T/3TC/NVP treatment.

RESULTS

The rate of treatment change among TAHOD patients starting d4T/3TC/NVP as their first antiretroviral treatment was 22.3 per 100 person-years, with lower baseline haemoglobin (i.e. anaemia) associated with slower rate of treatment change. The rate of clinical failure while on d4T/3TC/NVP treatment was 7.3 per 100 person-years, with baseline CD4 cell count significantly associated with clinical failure. After d4T/3TC/NVP was stopped, nearly 40% of patients did not restart any treatment and, of those who changed to other treatment, the majority changed to zidovudine (ZDV)/3TC/NVP and less than 3% of patients changed to a protease inhibitor (PI)-containing regimen. The rates of disease progression on the second-line regimen were similar to those on the first-line regimen.

CONCLUSION

These real-life data provide an insight into clinical practice in Asia and the Pacific region. d4T/3TC/NVP is maintained longer than other first-line regimens and change is mainly as a result of adverse effects rather than clinical failure. There is a need to develop affordable second-line antiretroviral treatment options for patients with HIV infection in developing countries.

[The clinical and biological tolerance of nevirapine among patients with AIDS under treatment at the Hospital of the Point G]

The national policy of assumption of responsibility of the PVVIH decided to put 80% of new inclusions under Triomune, 1st therapeutic line made up of 3TC + D4T + Nevirapine. The use of Nevirapine among patients VIH+ plays a very important part in improvement of the quality of their life. The goal of this study was to evaluate the clinical and biological tolerance of Nevirapine at the PVVIH under treatment ARV and having Nevirapine in their diagram. We had collected 102 files of patients. The average age was 38 years. Association Lamivudine + Stavudine + Nevirapine was the diagram most frequently prescribed (82.4%). The skin, mucous and neurological signs, digestive disorders, muscular signs, cardiopulmonary signs were frequently observed in the first month of the treatment but these symptoms became less frequent in the third month and disappeared at the 6th month. We observed disorders in hepatic and renal functional parameters, rise in the lymphocytes. We obtained a considerable increase in the rate of CD4 between the beginning of the treatment and the 6th month. The treatment schema of 3TC + D4T + Nevirapine gives an excellent clinical and biological tolerance. But, the study must continue to confirm these results over a longer period.

Nevirapine-based antiretroviral therapy started early in the course of tuberculosis treatment in adult Malawians

BACKGROUND

The tuberculosis (TB) mortality rate of registered TB patients in Malawi is 23%, and 59% of the deaths occur in the first 2 months of treatment. HIV-related complications appear to be an important cause. Starting antiretroviral therapy early during tuberculosis treatment may improve outcome but problems often arise with drug interactions, adherence, toxicity and immune reconstitution disease (IRD).

METHODS

We prospectively followed 27 HIV-infected adult Malawians after starting Triomune (a generic fixed drug combination of stavudine, lamivudine and nevirapine) in the second week of tuberculosis treatment.

RESULTS

At baseline, 88% had CD4+ T-cell counts <100 cells/ml, all were anaemic and 78% were malnourished. Five patients (19%) died, two withdrew consent and one stopped all drugs due to hepatitis. At 6 months, all but one of the 19 remaining patients had good virological results (16 patients: <400 copies/ml, two patients: <1,000 copies/ml) and the median CD4+ T cell increase was 170 cells/ml. Adverse events were numerous, particularly in the first 2 months. Suspected IRD episodes could be managed without treatment interruptions. During the lead-in phase, 59% of nevirapine plasma levels were sub-therapeutic despite good adherence, compared with only 14% during weeks 4 and 8.

CONCLUSION

It is feasible to start Triomune early during TB treatment with good treatment outcome. The nevirapine lead-in phase should be avoided when rifampicin-based tuberculosis treatment is started >1 week beforehand.

Long-term results of initial therapy with abacavir and Lamivudine combined with Efavirenz, Amprenavir/Ritonavir, or Stavudine

OBJECTIVE

To compare alternative class-sparing antiretroviral regimens in treatment-naive subjects.

DESIGN

Open-label, multicenter, randomized trial of up to 3 consecutive treatment regimens over 96 weeks.

METHODS

Two hundred ninety-one subjects received abacavir (ABC) and lamivudine and efavirenz (nonnucleoside reverse transcriptase inhibitors [NNRTIs]), ritonavir-boosted amprenavir (protease inhibitor [PI]), or stavudine (nucleoside reverse transcriptase inhibitor [NRTI]) by random assignment. The primary end points were the percentages of subjects with plasma HIV-1 RNA levels <400 copies/mL and time to treatment failure over 96 weeks.

RESULTS

Ninety percent of subjects completed 96 weeks of follow-up, and 79% remained on study treatment. At week 96, there were no differences between arms in the percentages of subjects with plasma HIV-1 RNA levels <400 and <50 copies/mL, mean changes in plasma HIV-1 RNA levels, time to treatment failure, time to first or second virologic failure, or CD4 cell counts. The NNRTI arm had a greater percentages of subjects with RNA levels <or=50 copies/mL at weeks 24 and 48 and a greater overall duration of plasma HIV-1 RNA levels <400 copies/mL. Three subjects in the NNRTI arm had treatment failure on their first regimen and switched therapy compared with 16 in the NRTI arm and 13 in the PI arm. Twenty-one subjects had hypersensitivity reactions attributed to ABC (7.3%). Fewer drugs were used by subjects in the NNRTI arm, and fewer subjects in the NNRTI arm used 3 drug classes.

CONCLUSIONS

All treatment regimens demonstrated excellent 96-week results. Secondary analyses favored the NNRTI regimen over the PI and NRTI regimens.

Pharmacokinetics of two generic fixed-dose combinations for HIV-infected children (Pedimune Baby & Pedimune Junior) are similar to the branded products in healthy adults

OBJECTIVES

Cipla Pharmaceuticals have developed generic fixed-dose combinations of stavudine, lamivudine and nevirapine for HIV-infected children (Pedimune Baby and Junior). We determined the pharmacokinetic profiles of stavudine, lamivudine and nevirapine in Pedimune and compared these with the branded products.

METHODS

This Phase I, comparative, single-centre, open-label, three-period, single-dose study was designed as a pilot study to exclude large differences in pharmacokinetics. Six healthy males were randomized to the following regimen sequences: ABC; ACB; BCA; BAC; CAB; CBA (A = reference, B = Pedimune Baby, C = Pedimune Junior). Single doses of medication were administered at 3 time points 4 weeks apart. An 8 h pharmacokinetic curve was recorded at day 1 of every cycle after medication intake. In addition, blood samples were taken on days 2, 3, 4, 8 and 15.

RESULTS

Non-parametric statistical tests revealed no statistically significant differences in Cmax (0.173 < or = P < or = 0.753) and Tmax (0.317 < or = P < or = 1.000) of stavudine, lamivudine and nevirapine between the two Pedimune formulations and the branded drugs. Also, there were no significant differences in AUC(0-infinity) of stavudine, lamivudine and nevirapine between Pedimune Junior and the branded drugs (0.345 < or = P < or = 0.600) and between Pedimune Baby and the branded drug for nevirapine (P = 0.463). In contrast, the AUC(0-infinity) of stavudine (mean change: +21%; P = 0.046) and lamivudine (mean change: +14%; P = 0.028) differed significantly between Pedimune Baby and the branded drugs, but these changes were considered not clinically significant.

CONCLUSIONS

The pharmacokinetic profiles of stavudine, lamivudine and nevirapine in Pedimune Baby and Junior are comparable to the branded products. Based on these results, it is acceptable to test the pharmacokinetics and dosing requirements of Pedimune in HIV-infected children.

Efficacy and safety of generic fixed-dose combination of stavudine, lamivudine and nevirapine (GPO-vir) in advanced HIV infection

OBJECTIVES

To assess the efficacy and safety of generic fixed-dose combination of stavudine, lamivudine and nevirapine; GPO-vir in advanced HIV infection.

MATERIAL AND METHOD

Open-label combined prospective and retrospective study involving 102 HIV infected patients with baseline CD4 cell count < 100 cells/mm3. All patients received GPO-vir for 48 weeks. The CD4 cell count and plasma viral load (pVL) was measured at 48 weeks.

RESULTS

The median baseline CD4 cell count and pVL were 13 cells/mm3 and 363,500 copies/ml, respectively. At 48 weeks, the median CD4 cell count increased to 191 cells/mm3 and 63.7% in intention-to treat and 82.3% in on-treatment analysis had pVL < 50 copies/ml. There was no significant difference in pVL between patients with baseline pVL > 100,000 or < or = 100,000 copies/ml (p = 0.312). The incidence of hepatotoxicity, rash and peripheral neuropathy was 4.9%, 14.7% and 6.9%, respectively.

CONCLUSION

GPO-vir was well tolerated and effective in increasing CD4 cell count and suppressing plasma viremia in advanced HIV infection during the 48 weeks follow-up period.

Pharmacokinetics of nevirapine: once-daily versus twice-daily dosing in the 2NN study

OBJECTIVE

As part of the large international, randomized 2NN trial, the pharmacokinetics of nevirapine in once-daily 400 mg and twice-daily 200 mg dosing regimens were investigated.

METHOD

Treatment-naive HIV-1-infected patients were randomized to receive nevirapine 400 mg once daily or 200 mg twice daily, in combination with lamivudine and stavudine. Blood samples were collected at several time-points (day 3, weeks 1, 2, 4, 24, and 48). Differences in pharmacokinetics between once- versus twice-daily dosing were investigated with nonlinear mixed effects modelling (NONMEM).

RESULTS

In total, 2,899 nevirapine plasma concentrations were available from 578 patients. Dosage and dosing frequency did not influence clearance or volume of distribution of nevirapine, indicating linear pharmacokinetic behavior of nevirapine whether given as a single daily dose or as divided doses over 24 hours. During steady state, the Cmin was lower (3.26 mg/L vs. 4.44 mg/L; p < .001) and the Cmax was higher (7.88 mg/L vs. 6.55 mg/L; p < .001) in the once-daily arm. However, compared to total variability in nevirapine levels for both treatments, these differences were minor. During steady state, total exposure, measured as AUC24h, was comparable for both regimens (133 mg/L*h vs. 133 mg/L*h; p = .084).

CONCLUSION

The daily exposure to nevirapine (AUC24h) was similar for the 400 mg once-daily and the 200 mg twice-daily dosing regimens. The Cmin of nevirapine is lower and the Cmax of nevirapine is higher for the once-daily regimen as compared to the twice-daily regimen. As a result, 200 mg nevirapine dosed twice daily may be preferred over 400 mg nevirapine dosed once daily.

Devenir à long terme d'un cas de périartérite noueuse cérébrale associée au VIH

INTRODUCTION

HIV-associated vasculitis is an infrequent entity, and only few data about its long-term evolution is available.

EXEGESIS

We report the long-term outcome of a patient with central nervous system HIV-associated periarteritis nodosa and then discuss the therapeutic options for this class of vasculitis.

CONCLUSION

This observation highlights the role of HAART in the treatment of HIV-associated vasculitis. Persistent remission can be obtained when viral replication is under control.

Nevirapine/lamivudine/stavudine as a combined-formulation tablet: bioequivalence study compared with each component administered concurrently under fasting condition

OBJECTIVE

The objective of the study was to compare the bioequivalence of a fixed-dose combination of a nevirapine 200 mg, lamivudine 150 mg and stavudine 30 mg combination tablet with application of the 3 medications, at the same dosage, concurrently as separate formulations, in healthy, adult subjects under fasting conditions.

MATERIAL AND METHODS

An open-label, balanced, randomized, 2-treatment, 2-period, 2-sequence, single-dose, crossover bioavailability study was conducted in 40 subjects with 21-day washout period between each treatment. Blood samples were collected for 168 hours. Plasma concentrations of nevirapine, lamivudine and stavudine were determined using a validated LC-MS-MS method. Noncompartmental pharmacokinetics and statistical analyses were performed using SAS (SAS Institute Inc., Cary, NC, USA) software (SAS System under Windows, Version 8.02).

RESULTS

The ratios of least-square means and the 90% confidence intervals of the log-transformed data were calculated for AUC(0-t), AUC(0-inf), and Cmax. The 90% confidence interval for least-square mean ratio between test and reference formulation for log-transformed parameters Cmax, AUC(0-t) and AUC(0-inf) were within the requirements of the 80-125% range.

CONCLUSION

The test formulation (Ranbaxy Laboratories Ltd., Gurgaon, India) is bioequivalent to the reference formulations both in terms of rate and extent of absorption after single-dose administration under fasting condition.

Generic fixed-dose combination antiretroviral treatment in resource-poor settings: multicentric observational cohort

BACKGROUND

The use fixed-dose combination (FDC) is a critical tool in improving HAART. Studies on the effectiveness of combined lamivudine, stavudine and nevirapine (3TC/d4T/NVP) are scarce.

OBJECTIVE

To analyse 6861 patients in a large observational cohort from 21 Médecins Sans Frontieres (MSF) HIV/AIDS programmes taking 3TC/d4T/NVP, with subcohort analyses of patients at 12 and 18 months of treatment.

METHODS

Survival was analysed using Kaplan-Meier method and factors associated with progression to death with Cox proportional hazard ratio.

RESULTS

Median baseline CD4 cell count at initiating of FDC was 89 cells/microl [interquartile range (IQR), 33-158]. The median follow-up time was 4.1 months (IQR, 1.9-7.3). The incidence rate of death during follow-up was 14.2/100 person-years [95% confidence interval (CI), 13.8-14.5]. Estimates of survival (excluding those lost to follow-up) were 0.93 (95% CI, 92-94) at 6 months (n = 2,231) and 0.90 (95% CI, 89-91) at 12 months (n = 472). Using a Cox model, the following factors were associated with death: male gender, symptomatic infection, body mass index < 18 kg/m and CD4 cell count 15-50 cells/microl or < 15 cells/microl. Subcohort analysis of 655 patients after 1 year of follow-up (M12 FDC cohort) revealed that 77% remained on HAART, 91% of these still on the FDC regimen; 5% discontinued the FDC because of drug intolerance. At 18 months, 77% of the patients remained on HAART.

CONCLUSIONS

Positive outcomes for d4T/3TC/NVP are reported for up to 18 months in terms of efficacy and safety.

Large-scale synthesis and formulation of GMP-grade stampidine, a new anti-HIV agent

The arylphosphoramidate derivative of stavudine (STV, d4T, 2,3'-didehydro-3'-deoxythymidine, CAS 3056-17-5), stampidine (STAMP, DDE-113, HI-113, N-[p-(4-bromophenyl)-2',3'-didehydro-3'-deoxy-5'-thymidylyl]-L-alanine methyl ester, CAS 217178-62-6), is a novel anti-HIV agent. STAMP was prepared under current Good Manufacturing Practice (cGMP) conditions on the scale of kilograms. Solid STAMP was subsequently formulated as a capsule under GMP conditions for oral administration.

Stavudine, lamivudine and nevirapine combination therapy for treatment of HIV infection and AIDS in adults

BACKGROUND

A favourable regimen for people infected with HIV/AIDS is one that provides optimal efficacy, durability of antiretroviral activity, tolerability, and has low adverse effects and drug-drug interactions. The combination of the non-nucleoside reverse transcriptase inhibitor nevirapine (NVP), and two nucleoside reverse transcriptase inhibitors, stavudine (d4T) and lamivudine (3TC), is widely used as first-line therapy, especially in low-resource countries. Analysis of the efficacy, durability and tolerability of the regimen is thus important to clinicians, consumers and policy-makers living in both rich and poor countries.

OBJECTIVES

To examine the efficacy of the stavudine, lamivudine and nevirapine regimen for the treatment of HIV infection and AIDS in adults.

SEARCH STRATEGY

We used the comprehensive search strategy developed specifically by the Cochrane HIV/AIDS Review Group to identify HIV/AIDS randomised controlled trials, and searched the following electronic databases: MEDLINE (searched July 2004); Embase (searched October 2004); and CENTRAL (July 2004). This search was supplemented with a search of AIDSearch (April 2005) to identify relevant conference abstracts, as well as searching reference lists of all eligible articles. The search was not limited by language or publication status.

SELECTION CRITERIA

Randomised controlled trials of the stavudine, lamivudine and nevirapine regimen, compared with any other regimens for treating HIV/AIDS, in antiretroviral treatment-naive or antiretroviral treatment-experienced adults.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed the methodological quality of the trials and extracted data.

MAIN RESULTS

Our search resulted in 1,148 records, of which two studies described trials that met our inclusion criteria. One trial was a small single-centre Australian trial of 70 antiretroviral-naive participants, while the other trial was a large, multicentre trial, conducted in 14 countries, of 1,216 antiretroviral-naive participants. In both trials over 60% of participants were male. As the therapeutic combinations compared in both trials were not identical, it was not possible to conduct a meta-analysis to increase the power of the results. The main findings, therefore, are from the much larger trial, which was of a high quality. This trial found that there was no statistically significant difference in the efficacy (measured by treatment failure) between nevirapine and efavirenz (EFZ), when used in combination with 3TC and d4T (RR = 1.16; 95%CI: 0.95, 1.41). There was no statistically significant difference between once daily or twice-daily dosing of NVP, when used in combination with 3TC and d4T (RR = 1.00; 95%CI: 0.83; 1.21). It also showed that, compared with NVP plus EFZ, 3TC and d4T, a once-daily dosing of NVP, in combination with 3TC and d4T, performs better in averting treatment failure (RR = 0.82; 95%CI: 0.67, 1.00) than does twice-daily dosing of NVP with 3TC and d4T (RR = 0.82; 95%CI: 0.69; 0.97). Frequency of toxicity was higher in participants receiving NVP, compared with EFZ.

AUTHORS' CONCLUSIONS

The combination of nevirapine, 3TC and d4T is as efficacious as a combination of efavirenz, 3TC and d4T. Once-daily NVP with twice-daily 3TC and d4T is as efficacious as twice-daily NVP, 3TC and d4T. However, toxicity may be increased in the once-daily NVP regime. Additional trials of sufficient duration are required to provide better evidence for the use of this combination as a first line therapy. Ideally, trials should use standardised assessment measures especially with respect to measuring viral load, so that results can be compared and combined in meta-analyses.

The 118I Reverse Transcriptase Mutation Is the Only Independent Genotypic Predictor of Virologic Failure to a Stavudine-Containing Salvage Therapy in HIV-1-Infected Patients

Patients infected with HIV-1 with more than 1000 HIV-1 RNA copies/mL, who were genotyped within 3 months before starting stavudine and treated for at least 3 months with a stable stavudine-containing highly active antiretroviral therapy, were selected from our database to identify the determinants of response to stavudine. Nonresponse was defined as a failure to achieve HIV-1 RNA level of less than 400 copies/mL or a reduction of more than 2 log10 by week 12. Univariate logistic analysis was used to elicit the failure-associated reverse transcriptase mutations (scored 1 to develop a genotype score). Eighty-one patients were eligible for the analysis, including 75 (93%) who previously received zidovudine. Thirty-five (43%) were nonresponders. Univariate logistic analysis revealed the following failure-associated mutations: 41L (P = 0.0001), 44D (P = 0.02), 118I (P = 0.0006), 184V (P = 0.04), 210W (P = 0.0004), and 215Y (P = 0.002) for a median stavudine score of 2. Failure was observed in 7 (18.9%) of 37 patients with a score less than 2, compared with 28 (63.6%) of 44 patients with a score of 2 or greater (P < 0.0001). The multivariable analysis showed that the 118I mutation (P = 0.04) was the only independent genotypic predictor of failing on a stavudine- containing highly active antiretroviral therapy.