A highly virulent variant of HIV-1 circulating in the Netherlands

We discovered a highly virulent variant of subtype-B HIV-1 in the Netherlands. One hundred nine individuals with this variant had a 0.54 to 0.74 log₁₀ increase (i.e., a ~3.5-fold to 5.5-fold increase) in viral load compared with, and exhibited CD4 cell decline twice as fast as, 6604 individuals with other subtype-B strains. Without treatment, advanced HIV-CD4 cell counts below 350 cells per cubic millimeter, with long-term clinical consequences-is expected to be reached, on average, 9 months after diagnosis for individuals in their thirties with this variant. Age, sex, suspected mode of transmission, and place of birth for the aforementioned 109 individuals were typical for HIV-positive people in the Netherlands, which suggests that the increased virulence is attributable to the viral strain. Genetic sequence analysis suggests that this variant arose in the 1990s from de novo mutation, not recombination, with increased transmissibility and an unfamiliar molecular mechanism of virulence.

Cost-effectiveness and Cost-utility of the Adherence Improving Self-management Strategy in Human Immunodeficiency Virus Care: A Trial-based Economic Evaluation

Background

Several promising human immunodeficiency virus (HIV) treatment adherence interventions have been identified, but data about their cost-effectiveness are lacking. This study examines the trial-based cost-effectiveness and cost-utility of the proven-effective Adherence Improving Self-Management Strategy (AIMS), from a societal perspective, with a 15-month time horizon.

Methods

Treatment-naive and treatment-experienced patients at risk for viral rebound were randomized to treatment as usual (TAU) or AIMS in a multicenter randomized controlled trial in the Netherlands. AIMS is a nurse-led, 1-on-1 self-management intervention incorporating feedback from electronic medication monitors, delivered during routine clinical visits. Main outcomes were costs per reduction in log10 viral load, treatment failure (2 consecutive detectable viral loads), and quality-adjusted life-years (QALYs).

Results

Two hundred twenty-three patients were randomized. From a societal perspective, AIMS was slightly more expensive than TAU but also more effective, resulting in an incremental cost-effectiveness ratio (ICER) of €549 per reduction in log10 viral load and €1659 per percentage decrease in treatment failure. In terms of QALYs, AIMS resulted in higher costs but more QALYs compared to TAU, which resulted in an ICER of €27759 per QALY gained. From a healthcare perspective, AIMS dominated TAU. Additional sensitivity analyses addressing key limitations of the base case analyses also suggested that AIMS dominates TAU.

Conclusions

Base case analyses suggests that over a period of 15 months, AIMS may be costlier, but also more effective than TAU. All additional analyses suggest that AIMS is cheaper and more effective than TAU. This trial-based economic evaluation confirms and complements a model-based economic evaluation with a lifetime horizon showing that AIMS is cost-effective.

Clinical Trials Registration

NCT01429142.

High Treatment Uptake in Human Immunodeficiency Virus/Hepatitis C Virus-Coinfected Patients After Unrestricted Access to Direct-Acting Antivirals in the Netherlands

Background

The Netherlands has provided unrestricted access to direct-acting antivirals (DAAs) since November 2015. We analyzed the nationwide hepatitis C virus (HCV) treatment uptake among patients coinfected with human immunodeficiency virus (HIV) and HCV.

Methods

Data were obtained from the ATHENA HIV observational cohort in which >98% of HIV-infected patients ever registered since 1998 are included. Patients were included if they ever had 1 positive HCV RNA result, did not have spontaneous clearance, and were known to still be in care. Treatment uptake and outcome were assessed. When patients were treated more than once, data were included from only the most recent treatment episode. Data were updated until February 2017. In addition, each treatment center was queried in April 2017 for a data update on DAA treatment and achieved sustained virological response.

Results

Of 23574 HIV-infected patients ever linked to care, 1471 HCV-coinfected patients (69% men who have sex with men, 15% persons who [formerly] injected drugs, and 15% with another HIV transmission route) fulfilled the inclusion criteria. Of these, 87% (1284 of 1471) had ever initiated HCV treatment between 2000 and 2017, 76% (1124 of 1471) had their HCV infection cured; DAA treatment results were pending in 6% (92 of 1471). Among men who have sex with men, 83% (844 of 1022) had their HCV infection cured, and DAA treatment results were pending in 6% (66 of 1022). Overall, 187 patients had never initiated treatment, DAAs had failed in 14, and a pegylated interferon-alfa-based regimen had failed in 54.

Conclusions

Fifteen months after unrestricted DAA availability the majority of HIV/HCV-coinfected patients in the Netherlands have their HCV infection cured (76%) or are awaiting DAA treatment results (6%). This rapid treatment scale-up may contribute to future HCV elimination among these patients.

[Revised prevention strategies for persons with (functional) hypo- or asplenie]

The Dutch guideline for the preventions of infections in persons with (functional) hypo- or asplenie has been revised, recommending adjustments for the use of vaccinations and antibiotics. The spleen has an important function in the defence against infections. Around 1,000 splenectomies are performed in the Netherlands every year. Three different groups of patients are distinguished: (a) persons with a partially or completely removed spleen after surgery or embolization; (b) persons with congenital asplenia; and (c) a heterogeneous group of patients, who may have functional hyposplenie or asplenia due to an underlying condition or specific treatments. Patients with asplenia have an increased risk of severe infections by encapsulated bacteria, including in particular Streptococcus pneumoniae, but also Haemophilus influenzae type b and Neisseria meningitides may lead to an increased risk S.pneumoniae causes up to 90% of the infections, which makes it the most important infectious agent in patients with asplenia. A number of preventive measures are recommended to prevent infections in patients with hypo- or asplenie, including the use of vaccinations and antibiotics and patient counselling.

A prospective, double-blind, randomized, placebo-controlled study on the efficacy and safety of influenza vaccination in myasthenia gravis

OBJECTIVE

To investigate the efficacy and safety of an influenza vaccination in patients with myasthenia gravis with acetylcholine receptor antibodies (AChR MG).

METHODS

An influenza vaccination or placebo was administered to 47 AChR MG patients. Before and 4 weeks after administration blood samples and clinical outcome scores were obtained. Antibodies to the vaccine strains A/California/7/2009 (H1N1)pdm09, A/Hong Kong/4801/14 (H3N2) and B/Brisbane/060/08 were measured using the hemagglutination-inhibition (HI) assay and disease-specific AChR antibody titers were measured with a radio-immunoprecipitation assay. Forty-seven healthy controls (HC) were vaccinated with the same influenza vaccine to compare antibody titers.

RESULTS

A post-vaccination, seroprotective titer (HI ≥ 1:40) was achieved in 89.4% of MG patients vs. 93.6% in healthy controls for the H3N2 strain, 95.7% vs 97.9% for the H1N1 strain and 46.8 vs 51% for the B-strain. A seroprotective titer for all three strains of the seasonal influenza vaccine was reached in 40.4% (19/47) of the MG group and in 51% (24/47) of the HC group. Immunosuppressive medication did not significantly influence post geomean titers (GMT). The titers of disease-specific AChR antibodies were unchanged 4 weeks after vaccination. The clinical outcome scores showed no exacerbation of MG symptoms.

CONCLUSION

The antibody response to an influenza vaccination in patients with AChR MG was not different from that in healthy subjects, even in AChR MG patients using immunosuppressive medication. Influenza vaccination does not induce an immunological or clinical exacerbation of AChR MG.

CLINICAL TRIAL REGISTRY

The influenza trial is listed on clinicaltrialsregister.eu under 2016-003138-26.

A Survey of Patients' Perspectives on Outpatient HIV Care in the Netherlands

Introduction

Responding to patients’ needs and preferences is important in the delivery of outpatient care. Recent and systematically collected data reflecting human immunodeficiency virus (HIV)-infected patients’ opinions on how their outpatient care should be delivered are lacking. Our aim was to identify aspects of care that people with HIV in outpatient care in The Netherlands consider important and to evaluate the extent to which the received care meets their expectations.

Methods

We measured patient preferences and experiences in a nationwide sample of HIV-infected patients using a modified, previously validated questionnaire (QUOTE-HIV).

Results

The aspects of care that were considered most important were specific expertise of the care provider in HIV medicine, the care provider taking the patient seriously and receiving adequate information about treatment options. In addition, confidentiality of HIV status at the outpatient clinic was a major concern. Patient experiences were positive, with the majority of the respondents indicating that they always or usually received care in accordance with their preferences.

Conclusion

HIV-infected patients greatly value having care providers with HIV-specific expertise. Safeguarding the privacy of HIV status and the provision of information about treatment options are matters that deserve continuous attention in the delivery of outpatient HIV care.

Electronic supplementary material

The online version of this article (doi:10.1007/s40121-017-0164-z) contains supplementary material, which is available to authorized users.

Effectiveness and cost-effectiveness of a nurse-delivered intervention to improve adherence to treatment for HIV: a pragmatic, multicentre, open-label, randomised clinical trial

BACKGROUND

No high-quality trials have provided evidence of effectiveness and cost-effectiveness of HIV treatment adherence intervention strategies. We therefore examined the effectiveness and cost-effectiveness of the Adherence Improving self-Management Strategy (AIMS) compared with treatment as usual.

METHODS

We did a pragmatic, multicentre, open-label, randomised controlled trial in seven HIV clinics at academic and non-academic hospitals in the Netherlands. Eligible participants were patients with HIV who were either treatment experienced (ie, with ≥9 months on combination antiretroviral therapy [ART] and at risk of viral rebound) or treatment-naive patients initiating their first combination ART regimen. We randomly assigned participants (1:1) to either AIMS or treatment as usual (ie, containing a range of common adherence intervention strategies) using a computer-generated randomisation table. Randomisation was stratified by treatment experience (experienced vs naive) and included block randomisation at nurse level with randomly ordered blocks of size four, six, and eight. 21 HIV nurses from the participating clinics received three training sessions of 6 h each (18 h in total) on AIMS and a 1·5 h booster training session at the clinic (two to three nurses per session) after each nurse had seen two to three patients. AIMS was delivered by nurses during routine clinic visits. We did mixed-effects, intent-to-treat analyses to examine treatment effects on the primary outcome of log₁₀ viral load collected at months 5, 10, and 15. The viral load results were exponentiated (with base 10) for easier interpretation. Using cohort data from 7347 Dutch patients with HIV to calculate the natural course of illness, we developed a lifetime Markov model to estimate the primary economic outcome of lifetime societal costs per quality-adjusted life-years (QALYs) gained. This trial is registered at ClinicalTrials.gov (number NCT01429142).

FINDINGS

We recruited participants between Sept 1, 2011, and April 2, 2013; the last patient completed the study on June 16, 2014. The intent-to-treat sample comprised 221 patients; 109 assigned to AIMS and 112 to treatment as usual. Across the three timepoints (months 5, 10, and 15), log viral load was 1·26 times higher (95% CI 1·04-1·52) in the treatment-as-usual group (estimated marginal mean 44·5 copies per mL [95% CI 35·5-55·9]) than in the AIMS group (estimated marginal mean 35·4 copies per mL [29·9-42·0]). Additionally, AIMS was cost-effective (ie, dominant: cheaper and more effective) since it reduced lifetime societal costs by €592 per patient and increased QALYs by 0·034 per patient.

INTERPRETATION

Findings from preparatory studies have shown that AIMS is acceptable, feasible to deliver in routine care, and has reproducible effects on medication adherence. In this study, AIMS reduced viral load, increased QALYs, and saved resources. Implementation of AIMS in routine clinical HIV care is therefore recommended.

FUNDING

Netherlands Organisation for Health Research and Development.

[Twenty years of combination antiretroviral therapy for HIV infection in the Netherlands: progression and new challenges]

Due to the introduction of combination antiretroviral therapy (cART) 20 years ago, HIV infection in the Netherlands has changed from a fatal disease to a chronic condition with a near normalized life expectancy. The average age of HIV-positive patients continues to increase, as does the prevalence of non-HIV-related comorbidity. The number of new HIV diagnoses seems to be decreasing in the Netherlands, which is partly due to increased testing, earlier diagnosis, prompt cART initiation, and achievement of high levels of viral suppression, resulting in a reduced likelihood of onward transmission. In order to further curb the epidemic, it is important that as yet undiagnosed people living with HIV are identified as soon as possible. All practicing physicians in the Netherlands can contribute to this goal.

Virological and Social Outcomes of HIV-Infected Adolescents and Young Adults in The Netherlands Before and After Transition to Adult Care

BACKGROUND

As a result of effective combination antiretroviral therapy (cART) and advanced supportive healthcare, a growing number of human immunodeficiency virus (HIV)-infected children survive into adulthood. The period of transition to adult care is often associated with impaired adherence to treatment and discontinuity of care. We aimed to evaluate virological and social outcomes of HIV-infected adolescents and young adults (AYAs) before and after transition, and explore which factors are associated with virological failure.

METHODS

We included 59 HIV-infected AYAs from the Netherlands who had entered into pediatric care and transitioned from pediatric to adult healthcare. We used HIV RNA load and cART data from the Dutch Stichting HIV Monitoring database (1996-2014), and collected social and treatment data from patients' medical records from all Dutch pediatric HIV treatment centers and 14 Dutch adult treatment centers involved. We evaluated risk factors for virological failure (VF) in a logistic regression model adjusted for repeated measurements.

RESULTS

HIV VF occurred frequently during the study period (14%-36%). During the transition period (from 18 to 19 years of age) there was a significant increase in VF compared with the reference group of children aged 12-13 years (odds ratio, 4.26 [95% confidence interval, 1.12-16.28]; P = .03). Characteristics significantly associated with VF were low educational attainment and lack of autonomy regarding medication adherence at transition.

CONCLUSIONS

HIV-infected AYAs are vulnerable to VF, especially during the transition period. Identification of HIV-infected adolescents at high risk for VF might help to improve treatment success in this group.

Patients' Willingness to Take Multiple-Tablet Antiretroviral Therapy Regimens for Treatment of HIV

BACKGROUND

The costs of combination antiretroviral therapy (cART) for HIV, consisting of separate, particularly generic, components (multiple-tablet regimens, MTR) are generally much lower than those of single-tablet regimens (STR) comprising the same active ingredients.

OBJECTIVES

To assess whether patients would be willing to take MTR, once-daily, instead of STR, with the goal of reducing general healthcare costs. In addition, we aimed to examine whether willingness was associated with particular patient characteristics.

METHODS

Data from the ATHENA cohort database in The Netherlands of adult HIV-1-infected patients in care and taking cART ≥6 months were used to select 1000 potential participants for an online patient survey on patient preferences and satisfaction. Participants were asked whether they would be willing to take three pills with the equivalent active ingredients simultaneously instead of STR to reduce costs. Multivariate logistic regression was used to examine associations between patient characteristics and willingness to take MTR instead of STR.

RESULTS

Forty-seven percent (n = 152) of the 322 respondents answered 'yes' and 26 % (n = 83) answered 'maybe' when asked whether they would be willing to take three pills with the equivalent active ingredients simultaneously to reduce costs. Non-Dutch patients were significantly more likely to answer 'no' (OR: 2.49; 95 % CI: 1.17-5.30) or 'maybe' (OR: 2.63; 95 % CI: 1.24-5.60). Answering 'no' was less common among patients who had been taking cART ≥15 years (OR: 0.23; 95 % CI: 0.09-0.58). Commonly reported concerns included the dosing frequency, efficacy and tolerability of MTR.

CONCLUSIONS

HIV-infected patients do not necessarily oppose the decision to prescribe MTR instead of STR to reduce healthcare costs. However, the potential trade-off in terms of convenience should be carefully weighed against the projected savings.

Structure and quality of outpatient care for people living with an HIV infection

Policy-makers and clinicians are faced with a gap of evidence to guide policy on standards for HIV outpatient care. Ongoing debates include which settings of care improve health outcomes, and how many HIV-infected patients a health-care provider should treat to gain and maintain expertise. In this article, we evaluate the studies that link health-care facility and care provider characteristics (i.e., structural factors) to health outcomes in HIV-infected patients. We searched the electronic databases MEDLINE, PUBMED, and EMBASE from inception until 1 January 2015. We included a total of 28 observational studies that were conducted after the introduction of combination antiretroviral therapy in 1996. Three aspects of the available research linking the structure to quality of HIV outpatient care were evaluated: (1) assessed structural characteristics (i.e., health-care facility and care provider characteristics); (2) measures of quality of HIV outpatient care; and (3) reported associations between structural characteristics and quality of care. Rather than scarcity of data, it is the diversity in methodology in the identified studies and the inconsistency of their results that led us to the conclusion that the scientific evidence is too weak to guide policy in HIV outpatient care. We provide recommendations on how to address this heterogeneity in future studies and offer specific suggestions for further reading that could be of interest for clinicians and researchers.

Acute hepatitis C in the Netherlands: characteristics of the epidemic in 2014

Within the Dutch Acute HCV in HIV Study, a surveillance system was initiated to estimate the incidence of hepatitis C virus (HCV) infections in 2014. Following the Dutch HIV treatment guidelines, HIV-positive men having sex with men (MSM) in 19 participating centers were screened. Ninety-nine acute HCV infections were reported, which resulted in a mean incidence of 11 per 1000 patient-years of follow-up. Unfortunately, the HCV epidemic among Dutch HIV-positive MSM is not coming to a halt.

Treatment of Pneumocystis pneumonia with intermediate-dose and step-down to low-dose trimethoprim-sulfamethoxazole: lessons from an observational cohort study

Background

The recommended treatment of Pneumocystis jirovecii pneumonia (PCP) is high-dose trimethoprim–sulfamethoxazole (TMP–SMX) in an equivalent of TMP 15–20 mg/kg/day and SMX 75–100 mg/kg/day for 2 or 3 weeks. High rates of adverse events are reported with this dose, which raises the question if lower doses are possible.

Methods

All adult patients diagnosed with PCP in various immune dysfunctions and treated with TMP–SMX between January 1, 2003 and July 1, 2013 in a tertiary university hospital were included. Per institutional protocol, patients initiated treatment on intermediate-dose TMP–SMX (TMP 10–15 mg/kg/day) and could be stepped down to low-dose TMP–SMX (TMP 4–6 mg/kg/day) during treatment. Clinical variables at presentation, relapse rate and mortality rates were compared between intermediate- and step-down treatment groups by uni- and multivariate analyses.

Results

A total of 104 patients were included. Twenty-four patients (23 %) were switched to low-dose TMP–SMX after a median of 4.5 days (IQR 2.8–7.0 days). One relapse (4 %) occurred in the step-down group versus none in the intermediate-dose group. The overall 30-day mortality was 13 %. There was 1 death in the step-down group (4 %) compared to 13 deaths (16 %) in the intermediate-dose group.

Conclusions

We observed high cure rates of PCP by treatment with intermediate-dose TMP–SMX. In addition, a step-down strategy to low-dose TMP–SMX during treatment in selected patients appears to be safe and does not compromise the outcome of treatment.

Durability of protective antibody titres is not enhanced by a two-dose schedule of an ASO3-adjuvanted pandemic H1N1 influenza vaccine in adult HIV-1-infected patients

The immune response after influenza vaccination is impaired in HIV-infected individuals and can be enhanced by a second dose. The durability of the antibody protection and its clinical benefit is not known. We investigated clinical symptoms and antibody titres against H1N1 influenza A following no dose, 1 dose, or 2 doses of an ASO3-adjuvanted H1N1 vaccine in HIV-infected patients. Seroprotection was found in 7.9%, 52.2%, and 57.3% of patients who received no dose, 1 dose, and 2 doses of the vaccine, respectively (p-value for group comparison < 0.001), after a median of 8.2 ± 1.6 months. Clinical symptoms suggestive of an influenza-like illness were slightly more frequently reported in the unvaccinated group. Vaccinated HIV-infected patients were more likely to be seroprotected at follow-up, but there was no difference comparing those who had received 1 or 2 doses of the vaccine.

Temporary treatment during primary HIV infection does not affect virologic response to subsequent long-term treatment

Temporary cART during primary HIV-infection (PHI) did not select for drug resistance mutations after treatment interruption and did not affect the subsequent virological response to long-term cART. Our data demonstrate that fear of drug resistance development is not a valid argument to refrain from temporary early treatment during PHI.

Hepatitis B surface antigen declines and clearance during long-term tenofovir therapy in patients coinfected with HBV and HIV

BACKGROUND

The kinetics of hepatitis B surface antigen (HBsAg) are predictive in HBV-infected patients treated with pegylated interferon. Knowledge about the value of HBsAg levels in patients coinfected with HBV and human immunodeficiency virus (HIV) is lacking.

METHODS

We quantified serum HBsAg in a Dutch multicenter cohort of 104 patients coinfected with HIV and HBV who were treated with tenofovir disoproxil fumarate (TDF) as part of highly active antiretroviral therapy. The median duration of therapy was 57 months (interquartile range, 34-72 months).

RESULTS

Hepatitis B e antigen (HBeAg)-positive patients achieved a decline of 2.2 log IU/mL in HBsAg, whereas HBeAg-negative patients only achieved a decline of 0.6 log IU/mL during 6 years of TDF therapy. Declines in HBsAg at months 6 and 12 correlated with CD4 cell count for HBeAg-positive patients. Five HBeAg-positive patients (8%) and 3 HBeAg-negative patients (8%) cleared HBsAg. HBeAg-negative patients who cleared HBsAg had lower baseline HBsAg as compared to patients who remained HBsAg positive. The majority of patients who cleared HBsAg achieved this end point within the first year. In HBeAg-positive patients, decline in HBsAg at month 6 was predictive of achieving HBsAg seroclearance.

CONCLUSIONS

Receipt of TDF therapy by HIV/HBV-coinfected patients for up to 6 years led to a significant decrease in HBsAg in the HBeAg-positive population. HBsAg kinetics early during treatment were predictive of HBsAg seroclearance and correlated with an increased CD4 cell count, underlining the importance of immune restoration in HBV clearance.

Soluble CD27 induces IgG production through activation of antigen-primed B cells

OBJECTIVES

High levels of soluble CD27 (sCD27), a marker of immune activation, are found in several infectious [including human immunodeficiency virus type-I (HIV-1)] and autoimmune diseases; however, a direct biological effect of sCD27 on B cells has not been established. The aim of this study was to investigate whether sCD27, by binding to CD70, can induce immunoglobulin G (IgG) production from B cells.

METHODS

B cells from healthy and HIV-1-infected individuals were cultured with recombinant human sCD27 (rhsCD27), and IgG production was measured. The role of rhsCD27 in inducing the expression of transcription factors involved in plasma cell differentiation was evaluated. Furthermore, we investigated the impact of different cytokines on the modulation of CD70 expression on B cells and the relationship between levels of IgG and sCD27 in serum from healthy and HIV-1-infected individuals.

RESULTS

We demonstrated that rhsCD27 induced IgG production from antigen-primed (CD27+) B cells. This effect was mediated by rhsCD27 binding to CD70 on B cells leading to activation of Blimp-1 and XBP-1, transcription factors associated with plasma cell differentiation. We found a significant correlation between levels of serum sCD27 and IgG in HIV-1-infected individuals and healthy controls.

CONCLUSIONS

sCD27 may act to enhance immunoglobulin production and differentiation of activated memory or recently antigen-experienced B cells, thus providing an activation signal to antigen-experienced B cells. This mechanism may operate during autoimmune and chronic infectious diseases, situations in which continuous immune activation leads to upregulation of CD70 expression and increased sCD27 cleavage.

[Prevention of severe infections in patients with hyposplenism or asplenia]

Each year, up to a 1000 splenectomies are performed in the Netherlands. Aside from patients without a spleen, there is also a large group of patients with hyposplenism or functional asplenia due to other primary diseases. All these patients are at risk of developing severe infections, such as post-splenectomy sepsis (PSS), which is associated with very high mortality. However PSS can partly be prevented by taking simple measures such as immunizations and prophylactic or early use of antibiotics. Healthcare professionals in first and secondary care in the Netherlands are generally not well informed about which preventive measures should be taken to prevent these infections, resulting in often suboptimal management of patients. In this article, recommendations are given on vaccination and administration of antibiotics to prevent severe infections such as PSS in this group of patients.

Changes in antigen-specific IgG1 Fc N-glycosylation upon influenza and tetanus vaccination

Antibody effector functions have been shown to be influenced by the structure of the Fc N-glycans. Here we studied the changes in plasma or serum IgG Fc N-glycosylation upon vaccination of 10 Caucasian adults and 10 African children. Serum/plasma IgG was purified by affinity chromatography prior to and at two time points after vaccination. Fc N-glycosylation profiles of individual IgG subclasses were determined for both total IgG and affinity-purified anti-vaccine IgG using a recently developed fast nanoliquid chromatography-electrospray ionization MS (LC-ESI-MS) method. While vaccination had no effect on the glycosylation of total IgG, anti-vaccine IgG showed increased levels of galactosylation and sialylation upon active immunization. Interestingly, the number of sialic acids per galactose increased during the vaccination time course, suggesting a distinct regulation of galactosylation and sialylation. In addition we observed a decrease in the level of IgG1 bisecting N-acetylglucosamine whereas no significant changes were observed for the level of fucosylation. Our data indicate that dependent on the vaccination time point the infectious agent will encounter IgGs with different glycosylation profiles, which are expected to influence the antibody effector functions relevant in immunity.

Outbreaks and clustering of Pneumocystis pneumonia in kidney transplant recipients: a systematic review

From 1980 onwards, an increasing number of outbreaks of Pneumocystis pneumonia (PCP) among kidney transplant recipients have been reported. The cause of these outbreaks is unclear and different explanations have been provided. We performed a systematic review to provide a comprehensive overview of the epidemiologic characteristics as well as the involved clinical risk factors. A total of 15 peer-reviewed English language articles published from 1980 onward were included. Outbreak settings were all marked by absence of adequate chemoprophylaxis, frequent inter-patient contacts and lack of isolation measures taken during hospitalization of PCP cases. PCP-associated mortality rates significantly decreased from a weighted mean of 38% before 1990 to 19% and 13% in the following two decades. Clinical risk factors for PCP in outbreak settings were largely similar to non-outbreak settings. Genotyping by multilocus sequence typing (MLST) or comparison of the internal transcribed spacer (ITS) regions 1 and 2 showed that the outbreaks are most frequently caused by a predominant or a single Pneumocystis strain. Pooled epidemiological data and genotyping results strongly support the theory that interhuman transmission of Pneumocystis occurred. No seasonal trend was noted. The results emphasize the need for chemoprophylaxis in kidney transplant recipients despite a low baseline incidence of PCP in this population, and support the current CDC recommendation with regard to isolation of patients with PCP during hospitalization.

Immunological analysis of treatment interruption after early highly active antiretroviral therapy

We longitudinally evaluated HIV-specific T-cell immunity after discontinuation of highly active antiretroviral therapy (HAART). After treatment interruption (TI), some individuals could maintain a low plasma viral load (<15,000 copies/mL), whereas others could not (>50,000 copies/mL). Before HAART was initiated, plasma viral load was similar. After TI, the numbers of CD8(+) T cells increased more in individuals without viral control, whereas individuals maintaining a low viral load showed a more pronounced increase in HIV-specific CD8(+) T-cell numbers. No differences were seen in the number or percentage of cytokine-producing HIV-1-specific CD4(+) T cells, or in proliferative capacity of T cells. Four weeks after TI, the magnitude of the total HIV-1-specific CD8(+) T-cell response (IFN-γ(+) and/or IL-2(+) and/or CD107a(+)) was significantly higher in individuals maintaining viral control. Degranulation contributed more to the overall CD8(+) T-cell response than cytokine production. Whether increased T-cell functionality is a cause or consequence of low viral load remains to be elucidated.

Response to 2009 pandemic influenza A (H1N1) vaccine in HIV-infected patients and the influence of prior seasonal influenza vaccination

Background

The immunogenicity of 2009 pandemic influenza A(H1N1) (pH1N1) vaccines and the effect of previous influenza vaccination is a matter of current interest and debate. We measured the immune response to pH1N1 vaccine in HIV-infected patients and in healthy controls. In addition we tested whether recent vaccination with seasonal trivalent inactivated vaccine (TIV) induced cross-reactive antibodies to pH1N1. (clinicaltrials.gov Identifier:NCT01066169)

Methods and Findings

In this single-center prospective cohort study MF59-adjuvanted pH1N1 vaccine (Focetria®, Novartis) was administered twice to 58 adult HIV-infected patients and 44 healthy controls in November 2009 (day 0 and day 21). Antibody responses were measured at baseline, day 21 and day 56 with hemagglutination-inhibition (HI) assay. The seroprotection rate (defined as HI titers ≥1∶40) for HIV-infected patients was 88% after the first and 91% after the second vaccination. These rates were comparable to those in healthy controls. Post-vaccination GMT, a sensitive marker of the immune competence of a group, was lower in HIV-infected patients. We found a high seroprotection rate at baseline (31%). Seroprotective titers at baseline were much more common in those who had received 2009–2010 seasonal TIV three weeks prior to the first dose of pH1N1 vaccine. Using stored serum samples of 51 HIV-infected participants we measured the pH1N1 specific response to 2009–2010 seasonal TIV. The seroprotection rate to pH1N1 increased from 22% to 49% after vaccination with 2009–2010 seasonal TIV. Seasonal TIV induced higher levels of antibodies to pH1N1 in older than in younger subjects.

Conclusion

In HIV-infected patients on combination antiretroviral therapy, with a median CD4+ T-lymphocyte count above 500 cells/mm³, one dose of MF59-adjuvanted pH1N1 vaccine induced a high seroprotection rate comparable to that in healthy controls. A second dose had a modest additional effect. Furthermore, seasonal TIV induced cross-reactive antibodies to pH1N1 and this effect was more pronounced in older subjects.

A randomized controlled study of accelerated versus standard hepatitis B vaccination in HIV-positive patients

BACKGROUND

In human immunodeficiency virus (HIV)-infected patients, the immunogenicity of hepatitis B vaccines is impaired. The primary and secondary aims of our study were to investigate the effectiveness and compliance of 2 different vaccination regimen in an HIV-infected population.

METHODS

A noninferiority trial with a 10% response margin was designed. Included were patients ≥ 18 years old, with negative HBsAg/anti-HBc serology, and not previously vaccinated against hepatitis B. Patients were stratified according to CD4(+) cell count: <200, 200-500, >500. Participants received 10 μg HBvaxPRO intramuscularly according to a 0-1-3 week schedule or the standard 0-4-24 week schedule. Anti-HBs levels were measured at week 28, considered protective ≥ 10 IU/L.

RESULTS

Modified intention to treat analysis in 761 patients was performed. Overall response difference was 50%(standard arm) versus 38.7% (accelerated arm) =11.3% (95% confidence interval [CI], [4.3, 18.3]), close to the 10% response margin. In CD4(+) cell count group 200-500 cells/mm(3,) the response difference was 20.8% (95% CI [10.9, 30.7]). However, the response difference in CD4(+)cell count group >500 cells/mm(3) was -1.8% (95% CI [-13.4,+9.7]). Compliance was significantly superior with the accelerated schedule, 91.8% versus 82.7% (P ≤ .001).

CONCLUSION

In HIV-infected patients, compliance with an accelerated hepatitis B vaccination schedule is significantly better. The efficacy of an accelerated schedule proved to be non-inferior in CD4(+) cell count group >500 cells/mm(3).

CLINICAL TRIALS REGISTRATION

CT00230061.

Severe course of Lyme neuroborreliosis in an HIV-1 positive patient; case report and review of the literature

Background

Lyme Neuroborreliosis (LNB) in a human immunodeficiency virus (HIV) positive patient is a rare co-infection and has only been reported four times in literature. No case of an HIV patient with a meningoencephalitis due to LNB in combination with HIV has been described to date.

Case presentation

A 51 year old woman previously diagnosed with HIV presented with an atypical and severe LNB. Diagnosis was made evident by several microbiological techniques. Biochemical and microbiological recovery during treatment was rapid, however after treatment the patient suffered from severe and persistent sequelae.

Conclusions

A clinician should consider LNB when being confronted with an HIV patient with focal encephalitis, without any history of Lyme disease or tick bites, in an endemic area. Rapid diagnosis and treatment is necessary in order to minimize severe sequelae.

Transient lowering of the viral set point after temporary antiretroviral therapy of primary HIV type 1 infection

Whether temporary antiretroviral treatment during primary HIV infection (PHI) lowers the viral set point or affects the subsequent CD4 count decline remains unclear. The objectives of this study were to analyze the clinical, viral, and immunological effects of temporary early HAART during PHI. This is a cohort study of patients with laboratory evidence of PHI. Independent predictors of early HAART and the viral set point were analyzed using multiple regression analysis. Plasma HIV-1 RNA (pVL) and CD4 trajectories were analyzed using linear mixed models. A total of 332 patients were included in the analysis. Sixty-four patients started HAART within 180 days of seroconversion. A higher baseline pVL was independently predictive of the start of early HAART (OR: 2.69/log10pVL, p = 0.001). Thirty-two patients who interrupted early HAART were compared with 250 patients who remained untreated for more than 180 days after seroconversion. Temporary early HAART was not significantly associated with a longer AIDS-free survival but did result in an initial, but transient lowering of the viral set point. The viral set point was initially 0.6 log copies/ml lower after interruption of early HAART (p < 0.001) and remained lower during 83 weeks of follow-up. No significant difference in the slopes of CD4 decline was detected between the groups. Temporary HAART in PHI is started more frequently in patients with a higher pVL and can transiently lower the viral set point compared to never treated patients.

Vaccination of HIV-infected adults

Vaccination has been shown to be one of the most powerful tools to decrease morbidity and mortality caused by an array of infectious diseases. The risk and complications of some vaccine-preventable diseases is higher in HIV-infected individuals, underscoring the importance of vaccination in these patients. However, the immune response upon vaccination is generally impaired and shorter lasting in HIV-infected individuals, especially in those with low CD4+ T-lymphocyte counts and detectable HIV RNA, as compared with healthy controls. Even in patients responding to antiretroviral treatment, an impaired immune response may persist despite normalization of the CD4+-cell count. Caution with live-attenuated vaccines is warranted in HIV-infected individuals with low CD4 T-lymphocyte counts. Decisions regarding administering a live-attenuated vaccine should be made after weighing the risks and benefits on an individual basis. In this article the immunology of vaccination in HIV-infected individuals, as well as the most relevant caveats of vaccination in this patient group, are reviewed in addition to the currently available information concerning the influenza A/H1N1 2009 monovalent vaccine.

Intradermal influenza vaccination in immunocompromized patients is immunogenic and feasible

BACKGROUND

Many strategies, including intradermal vaccination, have been tested to augment antibody responses upon vaccination. This strategy has not been evaluated in different groups of immunocompromized patients. We conducted a prospective, randomized study to compare the humoral response upon standard intramuscular influenza vaccination with the response upon reduced-dose intradermal vaccination in patients treated with anti-tumor necrosis factor (TNF)-alpha, human immunodeficiency virus (HIV)-infected patients, hematologic stem cell transplantation (HSCT) patients, and healthy controls.

METHODS

In total 156 immunocompromized patients and 41 healthy controls were randomized to receive either 0.5mL of the 2005/2006 trivalent influenza vaccine intramuscular or 0.1mL intradermal. Humoral responses, determined by hemagglutination inhibition assay, were measured before and 28 days postvaccination. Geometric mean titers (GMTs) and protection rates (PRs) are reported as primary outcomes, adverse events as a secondary outcome.

RESULTS

Reduced-dose intradermal vaccination leads to similar GMTs and PRs, within all tested groups, compared to the standard intramuscular vaccination. Healthy controls yielded significantly better GMTs and PRs than immunocompromized patients. Local skin reactions after intradermal vaccination occurred less frequent and were milder in immunocompromized patients than in healthy subjects and were predictive for a positive vaccination outcome for individual subjects.

CONCLUSIONS

Intradermal influenza vaccination is a feasible alternative for standard intramuscular vaccination in several groups of immunocompromized patients, including those treated with anti-TNF, HIV-infected patients and HSCT patients. The occurrence of a local skin reaction after intradermal vaccination is predictive of a response to at least one of the vaccine antigens.

[Practical advice for travellers with immune disorders]

For patients with immune disorders, the risk of infection during travel depends on the cause and severity of the immune disorder and the type of travel. Immunocompromised travellers experience more severe effects of illness than those without immune disorders. Some risks can be reduced or avoided by taking adequate precautions and, in some cases, modifying travel plans. Ensuring adequate medication use during the trip requires careful planning prior to travel. Regarding vaccination, immunocompromised travellers may have an impaired ability to generate antibodies; live attenuated vaccines are often contraindicated. The treating physician must take a proactive role when an immunocompromised patient indicates that he or she plans to travel. Protocols developed by the Dutch National Coordination Centre for Travellers Health (LCR) provide practical advice regarding a number of situations. Provided that they are given proper individualised advice, there is little concrete evidence to suggest that these patients should not travel anywhere they wish.

Influenza virus vaccination induces interleukin-12/23 receptor beta 1 (IL-12/23R beta 1)-independent production of gamma interferon (IFN-gamma) and humoral immunity in patients with genetic deficiencies in IL-12/23R beta 1 or IFN-gamma receptor I

To investigate whether protective immune responses can be induced in the absence of normal interleukin-12/23/gamma interferon (IL-12/23/IFN-gamma) axis signaling, we vaccinated with the seasonal influenza virus subunit vaccine two patients with complete IL-12/23 receptor beta1 (IL-12/23R beta 1) deficiencies, two patients with partial IFN-gamma receptor I (pIFN-gamma RI) deficiencies, and five healthy controls. Blood samples were analyzed before, 7 days after, and 28 days after vaccination. In most cases, antibody titers reached protective levels. Moreover, although T-cell responses in patients were lower than those observed in controls, significant influenza virus-specific T-cell proliferation, IFN-gamma production, and numbers of IFN-gamma-producing cells were found in all patients 7 days after the vaccination. Interestingly, influenza virus-specific IFN-gamma responses were IL-12/23 independent, in striking contrast to mycobacterium-induced IFN-gamma production. In conclusion, influenza virus vaccination induces IL-12/23-independent IFN-gamma production by T cells and can result in sufficient humoral protection in both IL-12/23R beta 1- and pIFN-gamma RI-deficient individuals.

The effect of anti-tumour necrosis factor alpha treatment on the antibody response to influenza vaccination

OBJECTIVES

The effect of anti-tumour necrosis factor (TNF) therapy on the antibody responses to vaccines is the subject of ongoing debate. Therefore, we investigated the effect of the three currently available anti-TNF agents on influenza vaccination outcomes in a patient population with long-standing disease.

METHODS

In a prospective cohort study, we assessed the antibody response upon influenza vaccination in 112 patients with long-standing autoimmune disease treated with immunosuppressive medication either with anti-TNF (etanercept, adalimumab or infliximab; n = 64) or without anti-TNF (n = 48) and a control group of 18 healthy individuals. Antibody responses were determined by haemagglutination inhibition assay, before and 4 weeks after vaccination.

RESULTS

The proportion of individuals with a protective titre (>or=40) after vaccination was large (80-94%) and did not significantly differ between the three groups. Post-vaccination geometric mean antibody titres against influenza (A/H3N2 and B) were significantly lower in the 64 patients treated with anti-TNF compared with the 48 patients not receiving anti-TNF, and the healthy controls.

CONCLUSIONS

The antibody response to influenza vaccination in patients treated with anti-TNF is only modestly impaired. The proportion of patients that achieves a protective titre is not significantly diminished by the use of TNF blocking therapies.

Therapeutic drug monitoring of the HIV protease inhibitor atazanavir in clinical practice

BACKGROUND

Therapeutic drug monitoring (TDM) is being applied for a number of antiretroviral agents. Little is known about the use of TDM for atazanavir.

METHODS

This is a retrospective cohort analysis on the use of TDM of atazanavir at three clinical sites in The Netherlands. Patients were divided into three groups: (i) all patients with evaluable data of plasma atazanavir concentrations and its relationship with hyperbilirubinaemia; (ii) patients who started atazanavir without documented evidence of protease inhibitor (PI) mutations; (iii) patients who started atazanavir with documented evidence of PI mutations. The genotypic inhibitory quotient (GIQ) was calculated by dividing the mean atazanavir plasma trough concentration by the number of PI mutations.

RESULTS

A total of 108 patients were included; 70 (65.8%) were using atazanavir/ritonavir (300/100 mg once daily). No significant relationship was observed between atazanavir plasma trough concentration and antiviral response in patients starting atazanavir without PI mutations (group 2; n = 82). In contrast, a significant relationship was observed between atazanavir GIQ and treatment response in patients starting atazanavir while having PI mutations (group 3; n = 26). The cut-off value for GIQ most predictive of virological failure was 0.23 mg/L/mutation: patients (n = 8) with a GIQ equal to or below this value had 50% virological failure whereas patients (n = 18) with a GIQ above 0.23 mg/L/mutation had only 11% virological failure (chi(2): P = 0.030). Atazanavir plasma trough concentrations were significantly related with the occurrence of increased total bilirubin concentrations.

CONCLUSIONS

TDM of atazanavir might be beneficial for patients with documented PI resistance or patients with hyperbilirubinaemia.

An outbreak of Pneumocystis jiroveci pneumonia with 1 predominant genotype among renal transplant recipients: interhuman transmission or a common environmental source?

BACKGROUND

An outbreak of Pneumocystis jiroveci pneumonia (PCP) occurred among renal transplant recipients attending the outpatient department at the Leiden University Medical Centre (Leiden, The Netherlands) from 1 March 2005 through 1 February 2006. Clinical, epidemiological, and molecular data were analyzed to trace the outbreak's origin.

METHODS

Renal transplant recipients with a clinical suspected diagnosis of PCP were included in the study. The diagnosis had to be confirmed by direct microscopy or real-time polymerase chain reaction of the dihydropteroate synthase gene in a bronchoalveolar fluid specimen. To detect contacts between patients, a transmission map was constructed. A case-control analysis was performed to asses whether infection was associated with certain wardrooms. Genotyping of Pneumocystis isolates was performed by sequence analysis of the internal transcribed spacer (ITS) number 1 and 2 gene regions.

RESULTS

Twenty-two confirmed PCP cases were identified; approximately 0-1 would have been expected over the same time period. No risk factor was predominantly present, and standard immunosuppressive regimens had not changed. Liver transplant recipients who used the same outpatient facilities had not acquired PCP. The transmission map findings were compatible with interhuman transmission on multiple occasions. The case-control study did not point to wardrooms as a common source. Genotyping by sequencing of the ITS1 and ITS2 gene regions revealed type Ne in 12 of 16 successfully typed samples. Genotype Ne was found in only 2 of 12 reference samples.

CONCLUSIONS

The clinical data and genotyping results are compatible with either interhuman transmission or an environmental source of infection. More complex models may account for PCP clusters.

Effects of Active Treatment Discontinuation in Patients With a CD4+ T-Cell Nadir Greater Than 350 Cells/mm3

OBJECTIVE

To evaluate the safety and efficacy of discontinuing highly active antiretroviral therapy (HAART) in HIV-1-positive patients who initiated HAART at a CD4+ T-cell count >350 cells/mm.

METHODS

Eligible patients were identified from the Dutch AIDS Therapy Evaluation, The Netherlands (ATHENA) national observational cohort. Interruption or continuation of HAART was offered to all.

RESULTS

Of 71 patients enrolled, 46 (64%) interrupted HAART (STOP group) and 25 (36%) continued HAART (control group). The median CD4+ T-cell nadirs at the start of HAART were 469 (interquartile range [IQR]: 430-720) cells/mm3 and 510 (IQR: 440-637) cells/mm3, respectively. At week 48, the median plasma HIV RNA level in the STOP group had stabilized at approximately pre-HAART values (4.55 log10, IQR: 4.2-4.9 copies/mL), but the CD4+ T-cell count still exceeded the pre-HAART count (563 cells/mm3, IQR: 450-710 cells/mm3). Only 5 patients (11%) had reinitiated HAART after 48 weeks, all for personal reasons. No Centers for Disease Control and Prevention category events or death occurred after interruption. In 6 (13%) of 46 patients, mild symptoms of acute retroviral rebound syndrome (ARVS) were identified. No improvement was observed in mental or physical health scores. In 37% of patients, nonnucleoside reverse transcriptase inhibitor drug concentrations were still detectable 1 week after stopping.

CONCLUSIONS

Although HAART can safely be interrupted in patients with a high CD4 T-cell nadir, no improvement in quality of life was established. Patients can experience ARVS, the risk for development of resistance after treatment interruption is realistic, and there is a potential hazard of HIV transmission to sexual partners. We would not actively advise stopping treatment in patients who started treatment too early according to current guidelines.

Loss of memory B cells impairs maintenance of long-term serologic memory during HIV-1 infection

Circulating memory B cells are severely reduced in the peripheral blood of HIV-1-infected patients. We investigated whether dysfunctional serologic memory to non-HIV antigens is related to disease progression by evaluating the frequency of memory B cells, plasma IgG, plasma levels of antibodies to measles, and Streptococcus pneumoniae, and enumerating measles-specific antibody-secreting cells in patients with primary, chronic, and long-term nonprogressive HIV-1 infection. We also evaluated the in vitro production of IgM and IgG antibodies against measles and S pneumoniae antigens following polyclonal activation of peripheral blood mononuclear cells (PBMCs) from patients. The percentage of memory B cells correlated with CD4+ T-cell counts in patients, thus representing a marker of disease progression. While patients with primary and chronic infection had severe defects in serologic memory, long-term nonprogressors had memory B-cell frequency and levels of antigen-specific antibodies comparable with controls. We also evaluated the effect of antiretroviral therapy on these serologic memory defects and found that antiretroviral therapy did not restore serologic memory in primary or in chronic infection. We suggest that HIV infection impairs maintenance of long-term serologic immunity to HIV-1-unrelated antigens and this defect is initiated early in infection. This may have important consequences for the response of HIV-infected patients to immunizations.

Pharmacokinetics of once-daily lopinavir/ritonavir and the influence of dose modifications

We studied the pharmacokinetics of lopinavir/ritonavir dosed at 800/200 mg a day in 20 HIV-1-infected patients, and evaluated the effect of dose modifications in the case of trough concentration (Ctrough) levels less than 1.0 mg/l. Ctrough levels after the daily administration of lopinavir/ritonavir were lower than with twice daily administration. Dose modifications in four patients with Ctrough levels less than 1.0 mg/l succeeded in only one patient. Therapeutic drug monitoring can identify patients with lower-than-expected lopinavir exposure in a larger study.

[Meningitis caused by Toscana virus during a summer stay in Italy]

A 44-year-old woman suffered fever, headache and meningism during a summer stay in a region of central Italy where sand-fly fever is endemic. A few days after returning to the Netherlands, she appeared mentally and physically slow but had no fever. Because of the possibility of viral meningitis an examination of the cerebrospinal fluid (CSF) was carried out. This revealed a cell count of 1074/3 cells. Toscana virus antibodies of the IgG and IgM subclass were detected in two respective serum samples and in the CSF. This led to the diagnosis 'Toscana virus meningo-encephalitis'. Toscana virus is classified amongst the sandfly fever virus group. These viruses are transmitted by sand flies (Phlebotomus species) which reside in humid areas around the Mediterranean. Toscana virus is the main cause of viral meningoencephalitis in some areas of central Italy and possibly in southern Spain. The patient recovered within a few days without antiviral therapy. Toscana virus meningo-encephalitis should be included in the differential diagnosis of holidaymakers with neurological symptoms returning from the Mediterranean.

Immune restoration disease in HIV-infected individuals receiving highly active antiretroviral therapy: clinical and immunological characteristics

BACKGROUND

HIV-infected patients responding to HAART can show a diverse spectrum of symptoms caused by inflammatory reaction. The pathogenesis of this phenomenon, called immune restoration disease (IRD), is unclear. This study describes the spectrum of IRD and analyses the immunological and clinical parameters that could be related to its development.

METHODS

In a retrospective, matched case-control study, 17 HIV-infected individuals who developed inflammatory symptoms < 12 months after initiation of HAART were included. HIV-infected controls were matched for age, gender and CDC classification. Factors included in the analysis were: CD4+ and CD8+ cell counts, deltaCD4+ and deltaCD8+, CD4/CD8 ratios, HIV-1-RNA load (VL), AVL and the number of CDC events prior to HAART.

RESULTS

The median time after initiation of HAART and developing IRD (n = 17) was 72 days (range 2-319). In nine cases (53%) a mycobacterial infection was identified as the underlying cause. HAART was started at a mean CD4+ count (+/- SD) of 55 x 10(6) /l (+/- 59) and 85 x 10(6) /l (+/- 78.0) for cases and controls, respectively (p = 0.13). After initiation of HAART, the CD4+ count showed a 10.6 fold increase at the onset of IRD in the cases and a 2.7 fold increase in the controls in an equal period of time (p = 0.020). The other parameters analysed did not differ significantly between cases and controls.

CONCLUSION

We conclude that the risk of developing IRD is associated with a high-fold increase in CD4+ lymphocytes. In this study, mycobacteria are the pathogens most frequently associated with IRD.

Vaccination with Rabies to Study the Humoral and Cellular Immune Response to a T-Cell Dependent Neoantigen in Man

We investigated the humoral (antigen-specific immunoglobulin isotypes, IgG subclasses, and avidity maturation) and cellular (antigen-specific in vitro proliferation) immune response in 18 healthy adult volunteers, following a primary and a single booster vaccination with the T-cell dependent neoantigen rabies administered at a 3-months interval. The IgG antibody titer showed a mean 31-fold increase (range 3-154) 4 weeks after the first vaccination and a memory response was observed after booster vaccination, i.e. high IgG titers, switch from IgM to IgG and IgA and increased antibody avidity. All healthy adults showed a rabies-induced proliferative response with a mean stimulation index of 45 (range 3.5-200) after in vitro stimulation of PBMC obtained at 4 weeks after booster vaccination. The results obtained in this study provide a frame of reference for the interpretation of specific immune responses to the T-cell dependent neoantigen rabies in patients suspected of a primary or secondary immunodeficiency. Humoral and cellular immune responses to the rabies neoantigen provide complementary information on the condition of the immune system of an individual. Five patients diagnosed with a combined immunodeficiency were vaccinated using the same protocol and showed a number of abnormalities, either in the humoral or the cellular immune response to the rabies neoantigen.

Saquinavir soft-gel capsules (Fortovase) give lower exposure than expected, even after a high-fat breakfast

BACKGROUND

The soft-gel capsule (sgc) of saquinavir has been developed in order to improve the poor oral bioavailability of the original hard-gel capsules. However, in a Dutch study population using saquinavir-sgc plasma levels were lower than expected. We hypothesised that this was caused by differences in the amount of fat in the meals of the study populations.

METHODS

8-h steady-state plasma curves after observed ingestion of 1200 mg saquinavir-sgc were recorded, concomitantly with a normal breakfast (600 kcal, 33% fat) on the first day, and a high-fat breakfast (1040 kcal, 54% fat) on the second day. Additionally, a comparison was made between saquinavir hard-gel capsules and saquinavir-sgc with or without grapefruit juice (n = 1). Furthermore, a comparison between saquinavir-sgc and ritonavir + saquinavir-sgc 400/400 mg bid was made (n = 1).

RESULTS

Although saquinavir exposure was improved by fat, grapefruit juice or ritonavir, exposure to saquinavir for all recorded curves was lower than expected. A large proportion of trough concentrations was below the efficacy threshold.

CONCLUSION

Intake of squinavir-sgc with high-fat meals or grapefruit juice may improve the pharmacokinetic profile. However, plasma concentrations may then still be lower than expected and insufficient for good antiviral efficacy. Probably the only way to reach adequate saquinavir concentrations is by combining saquinavir with ritonavir.