Reductions in Stavudine Dose Might Ameliorate Mitochondrial-Associated Complications Without Compromising Antiviral Activity

BACKGROUND

Stavudine (d4T) is a nucleoside analogue approved for the treatment of HIV infection. Concern has risen due to its association with mitochondrial toxicity. Given that the toxicity might be dose-dependent, we explored prospectively whether lowering d4T doses might improve the safety profile of the drug without compromising its antiviral activity.

METHOD

All HIV-infected patients seen at our institution during the first semester of year 2003 who were receiving a d4T-containing regimen and had plasma HIV RNA below 50 copies/mL for the previous 3 months were invited to participate in a trial in which half of patients reduced the dose of d4T from 40 to 30 mg bid (cases) and the other half continued with the same d4T dose (controls).

RESULTS

A total of 92 patients were recruited in the study: 47 cases and 45 controls. A total of 9 patients experienced virological failure during the following 12 months: 4 cases and 5 controls. No significant differences between groups were recognized for mean transaminase levels, cholesterol, triglycerides, and lactate at baseline nor over the 12-month follow-up period. Lipodystrophy was recognized in 20% of patients at baseline, without significant differences between groups, and no significant improvements were recognized in the d4T 30 mg bid arm after 12 months follow-up. However, a median significant increase of 2.23-fold in the mitochondrial DNA content in peripheral blood mononuclear cells (PBMCs) was recognized in a subset of 11 patients who reduced the d4T dose, whereas it remained unchanged in 10 controls.

CONCLUSION

A reduction in the d4T dose from 40 to 30 mg bid may ameliorate mtDNA depletion in PBMCs without compromising the antiviral activity of the drug. However, significant improvements on surrogate laboratory markers of mitochondrial toxicity or in lipoatrophy could not be recognized over 12 months follow-up.

Hepatic and Renal Safety Profile of Tenofovir in HIV-Infected Patients with Hepatitis C, Including Patients on Interferon Plus Ribavirin

The liver safety of tenofovir (TDF) was investigated in 142 HIV+ patients exposed to the drug for longer than 12 months. No evidence of liver enzyme elevations were seen, even in 66 patients with chronic hepatitis C virus (HCV) co-infection. Given that TDF is an adenosine analogue, like didanosine, exposure to ribavirin might increase intracellular phosphorylated TDF metabolites, which could result in a higher risk of nephrotoxicity. Signs of tubular dysfunction in blood or urine were not recognized in 17 HCV-HIV co-infected patients exposed to TDF during interferon plus ribavirin therapy.

Simplification from protease inhibitors to once- or twice-daily raltegravir: the ODIS trial

BACKGROUND

Raltegravir has demonstrated good antiviral activity and safety profile in twice-daily (bid) dosing. However, its long terminal elimination half-life might allow once-daily (qd) administration.

METHODS

Consecutive HIV-infected individuals at our clinic under protease inhibitor (PI)-based regimens with plasma HIV-RNA <50 copies/mL for > 24 weeks were invited to replace PIs with raltegravir. Patients were randomly assigned to raltegravir 800 mg qd, 400 mg bid, or twice daily for the first 3 months and then once daily.

RESULTS

A total of 222 patients completed 24 weeks of follow-up on raltegravir (149 once-daily arm, 35 twice-daily arm, and 38 twice-daily to once-daily arm). At inclusion, mean CD4+ count was 574±308 cells/µL. Within 24 weeks, 13 (5.9%) patients experienced virological failure: 12 (6.4%) in the once-daily arms, and 1 (2.9%) in the twice-daily arm (P = .18). The rate of virological failure was 16.2% (12/74) in patients with prior nucleoside reverse transcriptase inhibitor (NRTI) resistance but only 0.7% (1/148) in the rest (P < .001).

CONCLUSION

A switch from PIs to raltegravir in HIV-infected patients with undetectable plasma HIV-RNA effectively sustains viral suppression, as long as prior NRTI resistance had not been selected. No significant differences were seen when comparing raltegravir twice daily or once daily in this context, although once-daily dosing tended to perform less well.

Differences in liver fibrosis and response to pegylated interferon plus ribavirin in HIV/HCV-coinfected patients with normal vs elevated liver enzymes

Severity of liver fibrosis and response to pegylated interferon plus ribavirin (pegIFN-RBV) are not well known in HIV/HCV-coinfected patients with persistently normal alanine aminotransferase (PNALT). All HIV/HCV-coinfected patients who had been assessed for liver fibrosis using elastometry during 2005 at our clinic were evaluated. Those with at least 1 year with three prior consecutive ALT measurements below the upper limit of normality were compared with patients with elevated ALT. Response to pegIFN-RBV was assessed in a subset of these patients. We analysed 87 patients with PNALT and 122 with elevated ALT. Compared to patients with elevated ALT, those with PNALT were significantly more often women (42%vs 26%), had greater mean CD4 counts (565 vs 420 cells/mm³), had lower mean serum HCV-RNA (5.8 vs 6.2 log IU/ml) and were infected by HCV genotype 4 (33%vs 6%). Liver fibrosis was considered as severe (Metavir F3) in 10% of patients with PNALT, and another 4% had cirrhosis based on stiffness values. These numbers were 16% and 35% in patients with elevated ALT. Treatment with pegIFN-RBV was given to 22 and 45 patients with PNALT and elevated ALT, respectively. Sustained virological response was achieved in 50% and 29% of them. In the multivariate analysis, PNALT was independently associated with response (OR: 7.9; 95% CI: 1.4-45.2; P = 0.02). Nearly 15% of HIV/HCV-coinfected patients with PNALT showed advanced liver fibrosis (Metavir F3-F4 estimates by elastometry). In summary, response to pegIFN-RBV is higher in patients with PNALT than in those with elevated ALT. Therefore, treatment should not be denied in HIV/HCV-coinfected patients with PNALT.

Liver fibrosis in patients with chronic hepatitis C and persistently normal liver enzymes: influence of HIV infection

Liver fibrosis progress slowly in patients with chronic hepatitis C and persistently normal alanine aminotransferase (PNALT) compared to subjects with elevated aminotransferases. Differences in liver fibrosis according to human immunodeficiency virus (HIV) status in this population have not been examined. All patients with serum hepatitis C virus (HCV)-RNA and PNALT who underwent liver fibrosis assessment using elastometry since 2004 at three different European hospitals were evaluated. Patients previously treated with interferon were excluded. PNALT was defined as ALT below the upper limit of normality in at least three consecutive determinations within the last 12 months. Fibrosis stage was defined as mild (Metavir F0-F1) if stiffness < or =7.1 kPa; moderate (F2) if 7.2-9.4 kPa; severe (F3) if 9.5-14 kPa, and cirrhosis (F4) if >14 kPa. A total of 449 HIV-negative and 133 HIV-positive patients were evaluated. HIV-negative patients were older (mean age 51.8 vs 43.5 years) and more frequently females (63%vs 37%) than the HIV counterparts. Mean serum HCV-RNA was similar in both the groups (5.9 vs 5.8 log IU/mL). Overall, 78.8% of the HIV patients were on HAART and their mean CD4 count was 525 (+/-278) cells/microL. In HIV-negatives, liver fibrosis was mild in 84.6%; moderate in 8.7%, severe in 3.3% and cirrhosis was found in 3.3%. In HIV patients, these figures were 70.7%, 18.8%, 6%, and 4.5%, respectively. In the multivariate logistic regression analysis, older age (odds ratio or OR: 1.04; 95% confidence interval or CI: 1.02-1.07; P < 0.001) and being HIV+ (OR: 2.6; 95% CI: 1.21-5.85; P < 0.01) were associated with severe liver fibrosis or cirrhosis (F3-F4). Thus, severe liver fibrosis and cirrhosis are seen in 6.6% of the HCV-monoinfected and in 10.5% of HCV-HIV co-infected patients with PNALT. Some degree of liver fibrosis that justifies treatment is seen in 15% of the HCV-monoinfected but doubles to nearly 30% in HIV-HCV co-infected patients with PNALT.

Liver complications have reached a plateau as cause of hospital admission and death in HIV patients in Madrid

Hospital admissions and deaths due to liver-related complications as result of chronic viral hepatitis are globally on the rise in HIV patients. However, a steady decline in liver-related hospitalizations and deaths has occurred at our HIV clinic in Madrid since year 2003. Hepatic complications are currently still responsible for 8.7% of all hospital admissions and one-third of in-hospital deaths, with hepatitis C virus infection by far the leading etiologic agent.

Changing rates and patterns of drug resistance mutations in antiretroviral-experienced HIV-infected patients

Surveillance of drug resistance mutations in antiretroviral-experienced HIV(+) patients may provide useful information regarding options available for rescue interventions. All resistance tests performed from 1999 to 2005 on antiretroviral-experienced individuals at one reference laboratory in Madrid were examined. Only mutations associated with drug resistance recorded at the September 2006 IAS-USA list were considered. A total of 2137 specimens were analyzed. Overall, 71.1% showed resistance mutations to at least one drug class, 56.1% to at least two, and 21% to all three drug families. Resistance mutations were 65% for NRTI, 44.4% for NNRTI, and 42.5% for PI. Mutations T215Y/F, M184V, and M41L were the most frequent for NRTI. Their rate significantly declined since 1999. K65R significantly increased since 1999 (0.8%) to 2003 (7.3%) but declined up to 3.3% in 2005. For NNRTI, K103N significantly increased from 21.8% in 1999 to 29.5% in 2005 (p < 0.01). The most frequent PI resistance mutations were L90M (24.3%), V82X (19.9%), M46I/L (19.5%), and I54V (17.1%). The presence of five or more was 58.8% in 1999 but declined to 22.2% in 2005. The rate of drug resistance mutations causing NRTI and PI resistance has steadily declined in antiretroviral-experienced patients since 1999. The availability of a large number and/or more convenient NRTI as well as the wide use of ritonavir-boosted PI could explain these observations. However, broad PI cross-resistance was seen in nearly 25% of antiretroviral-experienced patients in 2005. Therefore, there is a still need for new antiretrovirals with different resistance profiles.

Treatment of Chronic Hepatitis B or C in HIV‐Infected Patients with Dual Viral Hepatitis

Dual chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) infections are recognized in 3%-5% of human immunodeficiency virus (HIV)-infected individuals. More severe liver disease is seen in these patients. Viral interference may account for the fact that replication of one virus generally predominates over replication of the other. The impact that treatment of HBV or HCV infection has on this reciprocal inhibition is not well established. No evidence of reactivation of either HBV or HCV was seen when complete suppression of the other predominant virus was achieved with specific therapy in 21 subjects with HIV infection and dual HBV/HCV infections. This information has important pathogenic implications and may influence therapeutic decisions.

Update on the treatment of chronic hepatitis C in HIV-infected patients

Liver disease is currently the second leading cause of death in HIV-infected persons in Western countries. Hepatitis C virus infection accounts for the majority of cases of hepatic illness in this population. Although great progress has been made in the treatment of chronic hepatitis C in HIV-positive patients, many challenges still remain unsolved. The combination of pegylated interferon plus ribavirin is the current treatment of choice in hepatitis C virus/HIV-coinfected patients, regardless of hepatitis C virus genotype. However, the limited efficacy of this therapy in the HIV setting makes necessary the development of new strategies and/or drugs for the treatment of hepatitis C infection. Several anti-hepatitis C virus compounds are currently under investigation, although most are still in the early stages of clinical development. There is a relatively large group of patients who will be unable to be treated with the current hepatitis C virus medication based on interferon, mainly due to contraindications such as serious neuropsychiatric or cardiovascular history. However, for those without contraindications, treatment should be provided with no restrictions at the start (e.g. asking unnecessarily for a liver biopsy), and reassessed at weeks 4 and 12, considering virologic responses. Treatment should only be continued in early virologic responders. The use of standard doses of ribavirin (1000-1200 mg/day) and for at least 12 months seems crucial to maximize the effect of current hepatitis C treatment in the HIV setting, while no further benefit seems to derive from using higher than recommended pegylated interferon dosages. In patients with rapid virologic response (undetectable viremia at week 4) to anti-hepatitis C therapy, shorter periods of therapy (24 weeks) may be advisable in hepatitis C genotypes 2 and 3. Finally, adequate selection of candidates and careful selection of concomitant antiretroviral medications must be encouraged. Patients with low CD4 percentages (< 15%) should be deferred for treatment and HAART prioritized in order to improve CD4 counts. When possible, nucleoside analogs such as zidovudine, stavudine, and abacavir should be replaced by others having no deleterious interactions with ribavirin (e.g. tenofovir, lamivudine, or emtricitabine). Didanosine should never be coadministered with ribavirin due to potential life-threatening complications.

Influence of Liver Fibrosis Stage on Plasma Levels of Antiretroviral Drugs in HIV‐Infected Patients with Chronic Hepatitis C

BACKGROUND

Most antiretrovirals are metabolized in the liver, and lower dosing could be advisable in patients with severe liver insufficiency.

METHODS

Plasma drug levels were measured in hepatitis C virus (HCV)/human immunodeficiency virus (HIV)-coinfected patients receiving nevirapine (NVP), efavirenz (EFV), lopinavir/ritonavir (LPV/r), or atazanavir (ATV) with or without ritonavir. Liver fibrosis was measured using elastometry.

RESULTS

A total of 268 coinfected patients with compensated liver disease were analyzed. Mean plasma levels were 6.1 micro g/mL for NVP (35 patients), 2.8 micro g/mL for EFV (46 patients), 5.8 micro g/mL for LPV (56 patients), 0.4 micro g/mL for ATV (58 patients), and 0.7 micro g/mL for ATV/r (73 patients). Overall, drug levels were higher in patients with cirrhosis than in those without cirrhosis for EFV (median, 3.4 vs. 1.9 micro g/mL; P<.01) and NVP (median, 6.6 vs. 5.8 micro g/mL; P=.33). EFV plasma levels above the toxic threshold (>4 micro g/mL) were more frequent in patients with cirrhosis than in those without (31% vs. 3%; P<.001). The same trend was seen for NVP levels >8 micro g/mL (50% vs. 27%; P=.27). By contrast, plasma levels of protease inhibitors (PIs) did not differ significantly between patients with and those without cirrhosis.

CONCLUSIONS

Liver clearance of nonnucleoside reverse-transcriptase inhibitors, particularly EFV, is impaired in patients with cirrhosis. No similar effect is seen for PIs. Assessment of liver fibrosis by noninvasive tools may identify HCV/HIV-coinfected patients who might benefit from therapeutic drug monitoring to avoid drug overexposure.

Immunological and virological effects of structured treatment interruptions following exposure to hydroxyurea plus didanosine

Both hydroxyurea (HU) and structured treatment interruptions (STI) have been investigated as therapeutic approaches to enhance immune responses in chronically HIV-infected individuals. HIV-specific T cell responses as well as T cell activation were analyzed longitudinally in 31 HIV-infected individuals who had been treated for the prior 12 months with didanosine (ddI) plus HU and thereafter completed three STI cycles consisting of 2 months off and 2 months on ddI-HU. Similar increases in plasma HIV-RNA were seen in each of the three cycles off therapy, whereas CD4 counts remained fairly stable along the study period. T cell activation paralleled the evolution of plasma HIV-RNA during the first STI cycle and waned afterward. At baseline most patients presented a high level of CD8+ responses to different HIV peptide pools and 23% of them had CD4+ responses to Gag and/or Env. The level of CD8+ responses against each pool was stable and did not increase during STI cycles, while CD4 responses tended to decline. However, the contribution of Nef-specific response to the total CD8 response tended to increase. In a multivariate model, both a higher baseline plasma HIV-RNA and a higher level of Nef-specific response contribution to the total CD8+ response were independently associated with lower plasma HIV-RNA increases during each of the three STI cycles. Nef-specific CD8+ responses might contribute to a better virological control of HIV replication following treatment interruptions in HIV-infected individuals and might be boosted by the immunomodulatory effect of HU.

CD4+ T cell recovery beyond the first year of complete suppression of viral replication during highly active antiretroviral therapy is not influenced by CD8+ T cell activation

CD38 expression on CD8(+) T cells was longitudinally assessed in 31 human immunodeficiency virus (HIV)-infected persons with undetectable plasma viremia who had undergone highly active antiretroviral therapy (HAART) for 12 months and were followed for a mean of 30 months thereafter. Overall, CD4(+)T cell counts increased during follow-up, whereas CD38 expression remained stable. However, a subset of patients showed declines in CD38 expression, and, conversely, another subset showed increases in CD38 expression. No association could be found between long-term gains in CD4(+) T cells and evolution of CD38 expression. Thus, activation of CD8(+) T cells does not seem to be associated with the extent of CD4(+) T cell recovery beyond the first year of successful HAART.

Complications in treating chronic hepatitis B in patients with HIV

The management of chronic hepatitis B virus (HBV) poses specific problems in the presence of HIV infection, as therapeutic approaches have to consider both HBV and HIV. There are currently four drugs approved for the treatment of chronic HBV: IFN-alpha, lamivudine, adefovir and entecavir. Furthermore, the dual antiviral activity against HIV and HBV of antiretrovirals such as tenofovir and emtricitabine broadens the armamentarium against HBV in the HIV-coinfected population. Nucleotide analogues adefovir and tenofovir have the advantage of a higher genetic barrier for resistance when compared with the nucleoside analogues lamivudine and emtricitabine. Fortunately, the two families do not share resistance mutations, allowing salvage therapy and the consideration of combination therapy for drug-naive individuals. Although response to IFN-alpha is poorer in HBV/HIV-coinfected patients compared with HBV-monoinfected individuals, the more potent pegylated forms of IFN-alpha have brought new hopes.

Failure of hepatitis C therapy in HIV-coinfected drug users is not due to a shift in hepatitis C virus genotype

Because most patients coinfected with hepatitis C virus (HCV) and human immunodeficiency virus (HIV) are injection drug users (IDUs) who might have been exposed to multiple HCV genotypes while sharing needles, coinfection with distinct HCV genotypes could be frequent in them. Blood samples from 203 coinfected IDUs who did not respond to at least 24 weeks of interferon (IFN)-based therapies were analyzed. At baseline, 131 patients had HCV genotype 1, 4 had HCV genotype 2, 52 had HCV genotype 3, and 16 had HCV genotype 4. Changes in HCV genotype were not found in any patient when samples obtained before and after HCV therapy were compared. HCV therapy did not appear to select for IFN-resistant HCV genotypes that might have been present at baseline. Coinfection with distinct HCV genotypes is unlikely in former IDUs coinfected with HIV and does not explain the lower efficacy of HCV therapy in this population.

Mitochondrial Dna Depletion in HIV-Infected Patients is More Pronounced with Chronic Hepatitis C and Enhanced following Treatment with Pegylated Interferon plus Ribavirin

Background

Mitochondrial DNA (mtDNA) damage seems to be responsible for many of the toxicities associated with the long-term use of nucleoside analogues in HIV-infected patients. These adverse effects, mainly lipoatrophy, seem to be even more pronounced in subjects with hepatitis C virus (HCV) co-infection. However, there is no information about a possible additive effect of HCV on mtDNA depletion nor about the impact of ribavirin use in HIV/HCV-coinfected individuals.

Patients and methods

mtDNA was measured in peripheral blood mononuclear cells (PBMC) collected from 192 individuals classified into 4 groups: HIV-neg/HCV-neg (control group, n=11), HIV-pos/HCV-neg (56), HIV-neg/HCV-pos (18) and HIV-pos/HCV-pos (107). A duplex real-time NASBA assay was used to quantify mtDNA on maximal platelet-depleted specimens and all experiments were run in duplicate. The mtDNA copy number per cell was estimated taking as reference the nuclear DNA copy number.

Results

The mean mtDNA values in the control group was 757 copies/cell, while it was 428, 349 and 296 for HIV-pos, HCV-pos and HIV/HCV-coinfected individuals, respectively ( P<0.001 for all groups relative to the control group). No significant differences were observed when comparing patients with HIV or HCV infections alone, but coinfected individuals showed a lower mtDNA copy number than patients infected with HIV ( P<0.001) or with HCV ( P=0.089). In a subset of 18 patients with HIV/HCV-coinfection, treatment with pegylated interferon plus ribavirin produced a further reduction in mtDNA (mean value, 189 copies/cell; P=0.009).

Conclusions

HIV and HCV may independently cause mtDNA depletion in PBMC. Coinfection may result in more pronounced mtDNA depletion. The administration of interferon plus ribavirin may further enhance mtDNA depletion. These findings may explain the greater risk of lipoatrophy of antiretroviral therapy in HIV-infected patients with HCV coinfection and why anti-HCV therapy may aggravate this effect.

Paradoxical CD4+ T-cell decline in HIV-infected patients with complete virus suppression taking tenofovir and didanosine

BACKGROUND

Tenofovir (TDF) and didanosine (ddI) are both adenosine analogues with convenient posology, strong potency and a relatively high genetic barrier for resistance. The popularity of this combination, however, has been questioned due to concerns about pharmacokinetic interactions and increased risk of pancreatitis and hyperglycemia. Less information is available about other possible side effects.

PATIENTS AND METHODS

HIV-infected individuals who initiated a protease inhibitor-sparing regimen between September 2002 and June 2003 at five hospitals, and had at least one subsequent visit within the next 12 months, always with complete virus suppression, were retrospectively assessed. Only drug-naive individuals and patients who simplified a prior successful antiretroviral regimen were analysed.

RESULTS

Outcomes were analysed in 570 individuals according to treatment modality (98 drug-naive versus 472 simplified); the nucleoside analogue (NA) backbone (298 with TDF + ddI, 88 with ddI, 44 with TDF, and 140 with neither ddI nor TDF); and the third agent used (378 with non-nucleoside analogues versus 192 with NA). Significant CD4+ T-cell declines were seen in patients taking ddI + TDF with respect to all other NA combinations, including ddI or TDF separately. Patients exposed to high ddI doses or taking a third NA showed more pronounced CD4 declines. Plasma levels of ddI correlated with the extent of CD4+ T-cell loss.

CONCLUSION

Patients receiving ddI + TDF-based combinations show CD4+ T-cell declines despite achieving complete virus suppression. This effect generally progresses with time. An imbalance in adenosine metabolites within CD4+ T lymphocytes may explain this phenomenon, which resembles the genetic purine nucleoside phosphorylase deficiency syndrome.

Mitochondrial DNA depletion in HIV-infected patients is more pronounced with chronic hepatitis C and enhanced following treatment with pegylated interferon plus ribavirin

BACKGROUND

Mitochondrial DNA (mtDNA) damage seems to be responsible for many of the toxicities associated with the long-term use of nucleoside analogues in HIV-infected patients. These adverse effects, mainly lipoatrophy, seem to be even more pronounced in subjects with hepatitis C virus (HCV) co-infection. However, there is no information about a possible additive effect of HCV on mtDNA depletion nor about the impact of ribavirin use in HIV/HCV-coinfected individuals.

PATIENTS AND METHODS

mtDNA was measured in peripheral blood mononuclear cells (PBMC) collected from 192 individuals classified into 4 groups: HIV-neg/HCV-neg (control group, n = 11), HIV-pos/HCV-neg (56), HIV-neg/HCV-pos (18) and HIV-pos/HCV-pos (107). A duplex real-time NASBA assay was used to quantify mtDNA on maximal platelet-depleted specimens and all experiments were run in duplicate. The mtDNA copy number per cell was estimated taking as reference the nuclear DNA copy number.

RESULTS

The mean mtDNA values in the control group was 757 copies/cell, while it was 428, 349 and 296 for HIV-pos, HCV-pos and HIV/HCV-coinfected individuals, respectively (P < 0.001 for all groups relative to the control group). No significant differences were observed when comparing patients with HIV or HCV infections alone, but coinfected individuals showed a lower mtDNA copy number than patients infected with HIV (P < 0.001) or with HCV (P = 0.089). In a subset of 18 patients with HIV/HCV-coinfection, treatment with pegylated interferon plus ribavirin produced a further reduction in mtDNA (mean value, 189 copies/cell; P = 0.009).

CONCLUSIONS

HIV and HCV may independently cause mtDNA depletion in PBMC. Coinfection may result in more pronounced mtDNA depletion. The administration of interferon plus ribavirin may further enhance mtDNA depletion. These findings may explain the greater risk of lipoatrophy of antiretroviral therapy in HIV-infected patients with HCV coinfection and why anti-HCV therapy may aggravate this effect.

Therapeutic immunization with an inactivated HIV-1 Immunogen plus antiretrovirals versus antiretroviral therapy alone in asymptomatic HIV-infected subjects

To determine whether the addition of an inactivated-gp120-depleted HIV-1 Immunogen to antiretrovirals (ARTs) conferred a beneficial effect on delaying time to virologic failure relative to that obtained by ARTs alone, a phase II clinical trial was performed in 243 asymptomatic, ART naïve, HIV-1 seropositive adults. The Cox model showed that HIV-1 Immunogen treatment was associated with a 34% decrease in the risk of virologic failure (P = 0.056). When the analysis incorporated baseline HIV-RNA stratification the risk of virologic failure in the HIV-1 Immunogen Arm was significantly reduced a 37% compared to the IFA placebo Arm (P = 0.034). The data suggest that therapeutic immunization plus ARTs could influence virologic control.

High rate of resistance to antiretroviral drugs among HIV-infected prison inmates

BACKGROUND

Resistance to antiretroviral (ARV) drugs represents a major obstacle to the success of HIV therapy. The aim of the study was to examine the prevalence of genotypic resistance to ARV drugs in a large group of HIV-infected individuals incarcerated in penal facilities.

MATERIAL/METHODS

We analyzed the reverse transcriptase and protease genes on plasma samples collected from 309 HIV-infected prison inmates in Madrid. In order to compare the prevalence of resistance at different periods and detect any trend over time, half of the samples from ARV-naive and half from pre-treated subjects were randomly collected in 1999 and in 2001.

RESULTS

Overall, 63.7% of specimens harbored plasma HIV-RNA above 1000 copies/ml. Genotypic data were obtained in 94.4% of them. Primary resistance mutations among 127 drug-naive subjects were recognized in 13% in 1999 vs. 15% in 2001. In contrast, drug resistance was found in 35% and 59% of 182 pre-treated subjects in 1999 and 2001.

CONCLUSIONS

Drug resistance has increased over the last two years among inmates on ARV drugs and currently affects 59% of those failing treatment. A nearly 3-fold increase has been noticed for NNRTI resistance. In comparison with HIV-positive subjects outside jail on ARV drugs, prisoners are more likely to experience virological failure, but show a lower rate of drug resistance; this affects particularly drugs with a low genetic barrier (i.e. NNRTI and 3TC).

A randomized trial to study first-line combination therapy with or without a protease inhibitor in HIV-1-infected patients

OBJECTIVE

To compare one protease inhibitor (PI)-based and two PI-sparing antiretroviral therapy regimens.

METHODS

International, open label, randomized study of antiretroviral drug-naive patients, with CD4 lymphocyte counts >/= 200 x 106 cells/l and plasma HIV-1 RNA levels > 500 copies/ml. Treatment assignment to stavudine and didanosine plus indinavir or nevirapine or lamivudine. Primary study endpoint was the percentage of patients with plasma HIV-1 RNA levels < 500 copies/ml after 48 weeks in the intention-to-treat analysis (ITT).

RESULTS

In total, 298 patients were enrolled. After 48 weeks, the percentage of patients in the indinavir, nevirapine and lamivudine arms with HIV-1 RNA < 500 copies/ml was 57.0%, 58.4% and 58.7%, respectively, in an ITT analysis. After 96 weeks of follow-up, these percentages were 50.0%, 59.6% and 45.0%, respectively. The percentage of patients with HIV-1 RNA < 50 copies/ml was significantly less for those allocated to lamivudine in an on-treatment analysis after 48 and 96 weeks of follow-up. Patients in the nevirapine arm experienced a smaller increase in the absolute number of CD4 T lymphocytes. There were no significant differences in the incidence of serious adverse events.

CONCLUSIONS

A comparable virological response can be achieved with first-line PI-base and PI-sparing regimens. The triple nucleoside regimen utilized may be less likely to result in viral suppression to < 50 copies/ml, while the nevirapine-based regimen is associated with a lower increase in CD4 T lymphocytes.

The use of PCR in the diagnosis of hyper-reactive malarial splenomegaly (HMS)

Between August 1997 and September 1998, 14 cases of hyper-reactive malarial splenomegaly (HMS) were diagnosed in the Instituto de Salud Carlos III in Madrid, Spain. These cases, from Equatorial Guinea and Cameroon, were identified using the diagnostic criteria established by Y. M. Fakunle in 1981: gross splenomegaly; high levels of anti-malarial antibodies; IgM in serum at least two standard deviations above the local mean; and clinical and immunological response to antimalarial treatment. Although malarial parasites were only detected in the Giemsa-stained blood films of four of the cases, these four and four others were found to have the DNA of such parasites in their blood when tested using a method based on a semi-nested, multiplex PCR. These result indicate that malarial parasitaemias may be more prevalent in HMS than is usually recognized.

Epidemiology of HTLV-I infection in Spain. HTLV Spanish Study Group

BACKGROUND

The human T-lymphotropic virus type I (HTLV-I) has been implicated in the genesis of tropical spastic paraparesis (TSP), adult T-cell lymphoma (ATL), and some cases of uveitis, subacute arthropathies, chronic dermatitis and lymphocytic alveolitis. The virus is endemic in some areas of the Caribbean basin, Japan, subSaharan Africa, Central and South America, Middle East and Melanesia. Given that HTLV-I is transmitted through similar ways to HIV, screening in blood donors is recommended in some countries.

MATERIALS AND METHODS

The clinical, epidemiological and virological characteristics of 27 patients with HTLV-I infection were identified in Spain up to September 1995.

RESULTS

Eighteen cases were Spanish natives and 9 were immigrants from endemic areas. Fifteen were male and 12 were female. The majority (12/18; 66.7 percent) of subjects born in Spain had resided in endemic areas or had had sexual partners from these regions. Four patients had TSP, three had ATL and one developed lymphomatous granulomatosis and T-cell lymphoma. The remaining HTLV-I subjects were asymptomatic at the time of diagnosis. Four cases were identified from screening of blood donors.

CONCLUSION

HTLV-I is present in Spain, affecting natives and, less frequently, immigrants from endemic areas. Both neurological and lymphoproliferative diseases have been recognized in a quarter of patients.

Latent Haemophilus influenzae pneumonia in patients infected with HIV

Pneumonia caused by common pyogenic bacteria occurs frequently in HIV-infected patients. Its clinical presentation has been described as being similar to that seen in non-immunosuppressed hosts but clearly different to that of opportunistic pneumonias. An atypical presentation has rarely been seen. In a 10-month period, we saw 12 HIV-infected patients who presented with Haemophilus influenzae pneumonia which was clinically and radiologically indistinguishable from Pneumocystis carinii pneumonia. Ten of the patients were intravenous drug users and were in different stages of HIV disease. The clinical picture was characterized by a prolonged course (median 4 weeks), non-productive cough, dyspnoea, and absence of findings usually present in bacterial pneumonia. Laboratory data frequently showed absence of leukocytosis, increased lactate dehydrogenase levels, hypoxaemia, and decreased CD4+ cell counts. All presented with interstitial or mixed bilateral infiltrates. Resistance to ampicillin and trimethoprim-sulphamethoxazole were each found in seven cases. Eleven patients were cured with antibiotic therapy, although five relapsed. H. influenzae pneumonia should be considered in HIV-infected patients who present with pulmonary symptoms and bilateral infiltrates of subacute or chronic onset. Clinical resolution of pneumonia is the usual outcome, but recurrences of infection are frequent.