Lipoprotein-based drug delivery

Lipoproteins (LPs) are circulating heterogeneous nanoparticles produced by the liver and intestines. LPs play a major role in the transport of dietary and endogenous lipids to target cells through cell membrane receptors or cell surface-bound lipoprotein lipase. The stability, biocompatibility, and selective transport of LPs make them promising delivery vehicles for various therapeutic and imaging agents. This review discusses isolation, manufacturing, and drug loading techniques used for LP-based drug delivery, as well as recent applications for diagnosis and treatment of cancer, atherosclerosis, and other life-threatening diseases.

Lipoproteins and lipoprotein mimetics for imaging and drug delivery

Lipoproteins are a set of natural nanoparticles whose main role is the transport of fats within the body. While much work has been done to develop synthetic nanocarriers to deliver drugs or contrast media, natural nanoparticles such as lipoproteins represent appealing alternatives. Lipoproteins are biocompatible, biodegradable, non-immunogenic and are naturally targeted to some disease sites. Lipoproteins can be modified to act as contrast agents in many ways, such as by insertion of gold cores to provide contrast for computed tomography. They can be loaded with drugs, nucleic acids, photosensitizers or boron to act as therapeutics. Attachment of ligands can re-route lipoproteins to new targets. These attributes render lipoproteins attractive and versatile delivery vehicles. In this review we will provide background on lipoproteins, then survey their roles as contrast agents, in drug and nucleic acid delivery, as well as in photodynamic therapy and boron neutron capture therapy.

[Recent development of natural and reconstituted lipoprotein based nano drug delivery vehicles]

Lipoproteins are biological lipids carriers. The natural and reconstituted lipoprotein based drug delivery systems have been extensively developed in recent years. This article reviews the development of natural and reconstituted low-density lipoprotein and high-density lipoprotein based vehicles in the antitumor area.

Pharmacokinetics of Micafungin in Healthy Volunteers, Volunteers With Moderate Liver Disease, and Volunteers With Renal Dysfunction

Micafungin is an antifungal agent metabolized by arylsulfatase with secondary metabolism by catechol-O-methyltransferase. The objectives of this study were to estimate the pharmacokinetic parameters and plasma protein binding of micafungin in volunteers with moderate hepatic dysfunction (n = 8), volunteers with creatinine clearance < 30 mL/min (n = 9), and matched controls (n = 8 and n = 9, respectively). Single-dose micafungin pharmacokinetics were estimated using noncompartmental techniques. There was a statistically lower area under the observed micafungin concentration-time curve (AUC) from time 0 to infinity for subjects with moderate hepatic dysfunction as compared to control subjects (97.5 +/- 19 microg.h/mL vs 125.9 +/- 26.4 microg.h/mL, P = .03), although there was no difference in micafungin weight-adjusted clearance (10.9 +/- 1.7 mL/h/kg vs 9.8 +/- 1.8 mL/h/kg, P = .2). The difference in area under the concentration-time curve may be explained by the differences in body weight between subjects and controls. Renal dysfunction did not alter micafungin pharmacokinetics.

Metabolism of triglyceride-rich lipoproteins and transfer of lipids to high-density lipoproteins (HDL) in vegan and omnivore subjects

BACKGROUND AND AIMS

Vegan diet excludes all foodstuffs of animal origin and leads to cholesterol lowering and possibly reduction of cardiovascular disease risk. The aim was to investigate whether vegan diet improves the metabolic pathway of triglyceride-rich lipoproteins, consisting in lipoprotein lipolysis and removal from circulation of the resulting remnants and to verify whether the diet alters HDL metabolism by changing lipid transfers to this lipoprotein.

METHODS AND RESULTS

21 vegan and 29 omnivores eutrophic and normolipidemic subjects were intravenously injected triglyceride-rich emulsions labeled with (14)C-cholesterol oleate and (3)H-triolein: fractional clearance rates (FCR, in min(-1)) were calculated from samples collected during 60 min for radioactive counting. Lipid transfer to HDL was assayed by incubating plasma samples with a donor nanoemulsion labeled with radioactive lipids; % lipids transferred to HDL were quantified in supernatant after chemical precipitation of non-HDL fractions and nanoemulsion. Serum LDL cholesterol was lower in vegans than in omnivores (2.1 ± 0.8, 2.7 ± 0.7 mmol/L, respectively, p < 0,05), but HDL cholesterol and triglycerides were equal. Cholesteryl ester FCR was greater in vegans than in omnivores (0.016 ± 0.012, 0.003 ± 0.003, p < 0.01), whereas triglyceride FCR was equal (0.024 ± 0.014, 0.030 ± 0.016, N.S.). Cholesteryl ester transfer to HDL was lower in vegans than in omnivores (2.7 ± 0.6, 3.5 ± 1.5%, p < 0,05). Free-cholesterol, triglyceride and phospholipid transfer were equal, as well as HDL size.

CONCLUSION

Remnant removal from circulation, estimated by cholesteryl oleate FCR was faster in vegans, but the lipolysis process, estimated by triglyceride FCR was equal. Increased removal of atherogenic remnants and diminution of cholesteryl ester transfer may favor atherosclerosis prevention by vegan diet.

Ligand-coupled lipoprotein for ovarian cancer-specific drug delivery

Lipoproteins are natural nanosized delivery vehicles within the circulatory system of all mammals. Scientists have long been interested in utilizing these endogenous macromolecules to transport exogenous imaging or therapeutic agents to specific cells or tissues in the body. The broad distribution of lipoprotein receptors throughout the body however has limited the utility of this approach for targeted delivery of medicinal agents. In recent years lipoprotein rerouting strategies have been developed wherein lipoproteins can be redirected from their natural lipoprotein receptors to an alternate receptor of choice. In this chapter we describe the basic methods of preparing folic acid-conjugated high-density lipoprotein nanoparticles for targeted delivery of imaging or chemotherapeutic agents to ovarian cancer cells.

Recombinant human tissue factor pathway inhibitor exerts anticoagulant, anti-inflammatory and antimicrobial effects in murine pneumococcal pneumonia

BACKGROUND

Streptococcus (S.) pneumoniae is the most common causative pathogen in community-acquired pneumonia and a major cause of sepsis. Recombinant human tissue factor pathway inhibitor (rh-TFPI) attenuates sepsis-induced coagulation and has been evaluated in clinical trials involving patients with sepsis and community-acquired pneumonia.

OBJECTIVE

To examine the effect of rh-TFPI on coagulation, inflammation and bacterial outgrowth in S. pneumoniae pneumonia in mice, with or without concurrent antibiotic treatment.

METHODS

Pneumonia was induced by intranasal inoculation with S. pneumoniae. Mice were treated with placebo, rh-TFPI, ceftriaxone or rh-TFPI combined with ceftriaxone. Early (8 h) and late (24 h) initiated treatments were evaluated. Samples were obtained 24 or 48 h after infection, for early and late initiated treatment, respectively. In vitro, placebo or rh-TFPI was added to a suspension of S. pneumoniae.

RESULTS

Rh-TFPI reduced pneumonia-induced coagulation; rh-TFPI with ceftriaxone further attenuated coagulation relative to ceftriaxone alone. Rh-TFPI inhibited accumulation of neutrophils in lung tissue and reduced the levels of several cytokines and chemokines in lungs and plasma in mice not treated with antibiotics; in these animals, rh-TFPI initiated 24 h after infection decreased pulmonary bacterial loads. In vitro, rh-TFPI also inhibited growth of S. pneumoniae.

CONCLUSIONS

Therapeutic rh-TFPI attenuates coagulation, inflammation and bacterial growth during pneumococcal pneumonia, whereby the latter two effects only become apparent in the absence of concurrent antibiotic treatment.

The protein moiety of Brucella abortus outer membrane protein 16 is a new bacterial pathogen-associated molecular pattern that activates dendritic cells in vivo, induces a Th1 immune response, and is a promising self-adjuvanting vaccine against systemic and oral acquired brucellosis

Knowing the inherent stimulatory properties of the lipid moiety of bacterial lipoproteins, we first hypothesized that Brucella abortus outer membrane protein (Omp)16 lipoprotein would be able to elicit a protective immune response without the need of external adjuvants. In this study, we demonstrate that Omp16 administered by the i.p. route confers significant protection against B. abortus infection and that the protective response evoked is independent of the protein lipidation. To date, Omp16 is the first Brucella protein that without the requirement of external adjuvants is able to induce similar protection levels to the control live vaccine S19. Moreover, the protein portion of Omp16 (unlipidated Omp16 [U-Omp16]) elicits a protective response when administered by the oral route. Either systemic or oral immunization with U-Omp16 elicits a Th1-specific response. These abilities of U-Omp16 indicate that it is endowed with self-adjuvanting properties. The adjuvanticity of U-Omp16 could be explained, at least in part, by its capacity to activate dendritic cells in vivo. U-Omp16 is also able to stimulate dendritic cells and macrophages in vitro. The latter property and its ability to induce a protective Th1 immune response against B. abortus infection have been found to be TLR4 dependent. The facts that U-Omp16 is an oral protective Ag and possesses a mucosal self-adjuvanting property led us to develop a plant-made vaccine expressing U-Omp16. Our results indicate that plant-expressed recombinant U-Omp16 is able to confer protective immunity, when given orally, indicating that a plant-based oral vaccine expressing U-Omp16 could be a valuable approach to controlling this disease.

Preparation and immunogenicity of capsular polysaccharide-surface adhesin A (PsaA) conjugate of Streptococcuspneumoniae

The efforts were focused on exploring alternative pneumococcal vaccine strategies, aimed at addressing the shortcomings of existing formulations, without compromising efficacy. We generated a stable Escherichia coli construct expressing functional recombinant PsaA and prepared CPS-rPsaA conjugate. The distribution of anti-CPS antibody response was almost completely of IgG2a subclass followed by IgG3 and low level of IgG1 subclass, which was opposite to the distribution of anti-PsaA IgG subclass antibodies. Though rPsaA was not detectable on the surface of the pneumococcal strain, the CPS-rPsaA conjugate possessed more accessibility to the surface of the strain. Mice immunized with conjugate exhibited rapid bacterial clearance from blood for the first 23h and afterward provided the best protection against challenge with pneumococcal 23F strain.

A Multicenter, Open-Label Clinical Study of Micafungin (FK463) in the Treatment of Deep-seated Mycosis in Japan

The efficacy and safety of micafungin (FK463), which is a new lipopeptide antifungal agent of the echinocandin class and is active against both Aspergillus and Candida species, were investigated in patients with deep-seated mycosis in this study. 70 patients were treated with micafungin 12.5-150 mg/d intravenously for up to 56 d. The overall clinical response rates were 60% (6/10) in invasive pulmonary aspergillosis, 67% (6/9) in chronic necrotizing pulmonary aspergillosis, 55% (12/22) in pulmonary aspergilloma, 100% (6/6) in candidemia, and 71% (5/7) in esophageal candidiasis. The response rates for patients with prior antifungal treatment which was considered ineffective or toxic, were similar to rates for patients without prior treatment. Mycological eradication was observed in patients infected with Aspergillus fumigatus, Aspergillus flavus, Aspergillus terreus, Aspergillus niger, Candida albicans, Candida glabrata, or Candida krusei. Adverse events related to micafungin were reported in 21 patients (30%), and there was no dose-related occurrence of any adverse event. It is concluded that treatment with micafungin as monotherapy seems to be effective and safe in patients with deep-seated mycosis.

Streptococcus pneumoniaeProtein Vaccine Candidates: Properties, Activities and Animal Studies

Streptococcus pneumoniae is a causative agent for community acquired pneumonia, bacteremia, acute otitis media, and meningitis. Recent emergence of multi-drug resistant clinical isolates prompts the need of effective vaccine for the prevention of disease. The licensed polysaccharide-based pneumococcal vaccines only elicit protective antibodies against the infection of serotypes that are included in the vaccine. To broaden the protection, the use of pneumococcal proteins will be a feasible and preferable alternative. This communication provides a review on the biochemical properties of these protein candidates, their immunization results in animal studies, and perspectives on the development of protein-based pneumococcal vaccine.

Intravenous injection of micafungin counteracts Candida albicans-induced aggravation of duodenal ulcers caused by cysteamine in rats

BACKGROUND

We have reported previously that Candida albicans is involved in the pathogenesis of peptic ulcer perforation; it was shown that C. albicans aggravated the severity of duodenal ulceration and increased the rate of perforation. We considered it incumbent upon us to ascertain whether C. albicans is a virulence factor involved in peptic ulcer perforation. In the present study, we administered an antifungal drug (micafungin) intravenously to rats that had received intragastric (i.g.) administration of C. albicans and cysteamine, in order to examine that micafungin could counteract the C. albicans-aggravation of duodenal ulcers.

METHODS

Cysteamine was administered thrice on day 1 to male Wistar rats. C. albicans was administered to the animals 1 h before, and 12 and 24 h after the first administration of cysteamine. Micafungin (n = 22) or saline (n = 24) was administered 12, 24, and 48 h after the administration of cysteamine.

RESULTS

The area of the duodenal ulcers was also significantly smaller in the micafungin group (P < 0.05). In addition, the survival rate of the rats was significantly higher in the micafungin group (P < 0.05). While in the control group, the ulcer base was found to be colonized by C. albicans, there was no evidence of the presence of C. albicans in the micafungin group.

CONCLUSION

It was shown that intravenous injection of micafungin counteracted the aggravation by C. albicans of cysteamine-induced duodenal ulcers in rats. This finding supports the concept that C. albicans is an aggravating factor for peptic ulcers.

Economic analysis of micafungin versus liposomal amphotericin B for treatment of candidaemia and invasive candidiasis in Germany

OBJECTIVE

To investigate the economic impact of micafungin (MICA) for treatment of invasive candidiasis and candidaemia (systemic Candida infections), a health economic analysis was conducted comparing MICA with liposomal amphotericin B (L-AMB).

RESEARCH DESIGN AND METHODS

The model was based on a phase III, randomised, double-blind, clinical trial which compared MICA with L-AMB. The model entailed a period of 14-20 weeks starting from initiation of treatment and was analysed from a German hospital perspective.

MAIN OUTCOME MEASURES

The main outcome measures were defined as the percentage of patients achieving clinical and mycological response after initial treatment and who were alive at the end of the study (EOS), and the total treatment-associated costs over the study period.

RESULTS

The health economic analysis shows that with MICA, 52.9% of patients are successfully treated and were alive at EOS compared to 49.1% for L-AMB. In addition, MICA has, on average, lower treatment-associated costs than L-AMB with euro43 243 and euro49 216 per patient, respectively. Because the costs are lower and the effectiveness is higher for MICA in comparison with L-AMB, MICA is more cost-effective than L-AMB. However, the results of the probabilistic sensitivity analysis show that the differences cannot be considered significant due to a large variance, although MICA remained the most cost-effective option throughout the one-way sensitivity analyses.

CONCLUSIONS

The lower costs and higher effectiveness reported for MICA versus L-AMB in this analysis indicate that MICA may be a more cost-effective therapy in the treatment of invasive candidiasis and candidaemia when compared with L-AMB.

[Case of bronchocentric granulomatosis that became recognized in the course of allergic bronchopulmonary aspergillosis]

A 56-year-old man with allergic bronchopulmonary aspergillosis (ABPA) was admitted due to the appearance of nodular opacities in the right upper lung field on chest radiography, after discontinuing itraconazole and clarithromycin on the suspicion of possible hepatic adverse effects. Chest CT scans on admission revealed nodular opacities in the right S3 and lingula bronchus, and bilateral bronchiectasis with mucoid impactions. A specimen obtained by transbronchial lung biopsy showed complete replacement of bronchioles by necrotizing granulomatous inflammation, containing the diagnosis of bronchocentric granulomatosis. Treatment with corticosteroids and micafungin sodium resulted in marked resolution of nodular opacities and mucoid impacts. This case suggests that abrupt cessation of antifungal agents and macrolides may provoke acute exacerbation of ABPA and development of bronchocentric granulomatosis.

Immunological responses and long-term treatment interruption after human immunodeficiency virus type 1 (HIV-1) lipopeptide immunization of HIV-1-infected patients: the LIPTHERA study

We studied the time course of immunological and virological markers after highly active antiretroviral therapy (HAART) interruption in chronically human immunodeficiency virus type 1 (HIV-1)-infected patients immunized with an HIV lipopeptide preparation. In a prospective open pilot study, 24 HIV-1-infected HAART-treated patients with undetectable plasma viral loads (pVLs) and CD4(+) T-cell counts above 350/mm(3) were immunized at weeks 0, 3, and 6 with a candidate vaccine consisting of six HIV lipopeptides. At week 24, patients with pVLs of <1.7 log(10) copies/ml were invited to stop taking HAART. Antiretroviral therapy was resumed if the pVL rose above 4.47 log(10) copies/ml and/or if the CD4(+) cell count fell below 250/mm(3). Immunological and virologic parameters were studied before and after HAART interruption. The median baseline and nadir CD4(+) cell counts were 482 (interquartile range [IQR], 195 to 826) and 313 (IQR, 1 to 481)/mm(3), respectively. New specific CD8(+) cell responses to HIV-1 epitopes were detected after immunization in 13 (57%) of 23 assessable patients. Twenty-one patients were evaluated 96 weeks after HAART interruption. The median time to pVL rebound was 4 weeks (IQR, 2 to 6), and the median peak pVL was 4.26 (IQR, 3 to 5) log(10) copies/ml. Thirteen of these 21 patients resumed HAART a median of 60 weeks after immunization (IQR, 9.2 to 68.4 weeks), when the median pVL was 4.8 (IQR, 2.9 to 5.7) log(10) copies/ml and the median CD4(+) cell count was 551 (IQR, 156 to 778)/mm(3). Eight patients were still off therapy at 96 weeks, with a median pVL of 4 (IQR, 1.7 to 4.6) log(10) copies/ml and a median CD4(+) cell count of 412 (IQR, 299 to 832)/mm(3). No clinical disease progression had occurred. Despite the lack of a control arm, these findings warrant a randomized study of therapeutic vaccination with HIV lipopeptides followed by long-term HAART interruption in AIDS-free chronically infected patients.

A review of the new antifungals: posaconazole, micafungin, and anidulafungin

This column reviews 3 new systemic antifungal agents (posaconazole, micafungin, and anidulafungin) from the standpoint of dermatology. Posaconazole, approved to treat invasive Aspergillus and Candida infections, is available in an oral suspension and resembles fluconazole, but seems to have a broader spectrum of activity. Posaconazole is effective against yeasts and molds and could be effective in treating rare fungal infections involving Zygomycetes, Mucor necrotizing fasciitis, rhinocerebral mucormycosis, some Fusarium species, Penicillium, Histoplasma, Blastomyces, Coccidioides, Paracoccidioides, and sporotrichosis, chromoblastomycosis, mycetoma, and phaeohyphomycosis, including Scedosporium apiospermum and Exophiala, Alternaria, and Bipolaris species. Posaconazole may abate onychomycosis and dermatophytes, but clinical trial data is lacking. Micafungin and anidulafungin are echinocandins like caspofungin and are useful salvage therapy for invasive aspergillosis and candidiasis. The exciting new agents have extended the armamentarium against antifungal pathogens, but have yet to find their place in the dermatologic practice.

Micafungin versus Caspofungin for Treatment of Candidemia and Other Forms of Invasive Candidiasis

BACKGROUND

Invasive candidiasis is an important cause of morbidity and mortality among patients with health care-associated infection. The echinocandins have potent fungicidal activity against most Candida species, but there are few data comparing the safety and efficacy of echinocandins in the treatment of invasive candidiasis.

METHODS

This was an international, randomized, double-blind trial comparing micafungin (100 mg daily) and micafungin (150 mg daily) with a standard dosage of caspofungin (70 mg followed by 50 mg daily) in adults with candidemia and other forms of invasive candidiasis. The primary end point was treatment success, defined as clinical and mycological success at the end of blinded intravenous therapy.

RESULTS

A total of 595 patients were randomized to one the treatment groups and received at least 1 dose of study drug. In the modified intent-to-treat population, 191 patients were assigned to the micafungin 100 mg group, 199 to the micafungin 150 mg group, and 188 to the caspofungin group. Demographic characteristics and underlying disorders were comparable across the groups. Approximately 85% of patients had candidemia; the remainder had noncandidemic invasive candidiasis. At the end of blinded intravenous therapy, treatment was considered successful for 76.4% of patients in the micafungin 100 mg group, 71.4% in the micafungin 150 mg group, and 72.3% in the caspofungin group. The median time to culture negativity was 2 days in the micafungin 100 mg group and the caspofungin group, compared with 3 days in the micafungin 150 mg groups. There were no significant differences in mortality, relapsing and emergent infections, or adverse events between the study arms.

CONCLUSIONS

Dosages of micafungin 100 mg daily and 150 mg daily were noninferior to a standard dosage of caspofungin for the treatment of candidemia and other forms of invasive candidiasis.

Population pharmacokinetics of micafungin in pediatric patients and implications for antifungal dosing

The echinocandins potentially have an important role in treatment of infections caused by Candida spp. and Aspergillus spp. in immunocompromised children. However, there are no population pharmacokinetic models of the echinocandins for pediatric patients. The safety and descriptive pharmacokinetics of micafungin in children were recently reported. However, a population pharmacokinetic model in children is needed in order to accurately determine the dosage of micafungin that produces an equivalent magnitude of drug exposure to that observed in adults. In order to explore the effect of weight on micafungin pharmacokinetics, a standard two-compartment pharmacokinetic model, a linear model, and an allometric power model were developed. For all three models, the fit to the data was excellent, with comparable measures of precision and bias. However, the superior log-likelihood value of the allometric power model suggested that it best reflected the data and was therefore chosen for a more detailed analysis of the magnitude and pattern of drug exposure which develop following the administration of micafungin. The allometric power model suggested that clearance in smaller children is higher than that predicted on the basis of weight alone. Consequently, a degree of dosage increase is required in smaller children to ensure comparable levels of drug exposure to those observed in larger children and adults. The allometric power model developed in this study enables identification of pediatric dosage regimens of micafungin which, based upon Monte Carlo simulations, result in equivalent drug exposures to those observed in adults, for which antifungal efficacy has been established.

Antibodies generated in cats by a lipopeptide reproducing the membrane-proximal external region of the feline immunodeficiency virus transmembrane enhance virus infectivity

The immunogenicity of a lipoylated peptide (lipo-P59) reproducing the membrane-proximal external region (MPER) of the transmembrane glycoprotein of feline immunodeficiency virus (FIV) was investigated with cats. In the attempt to mimic the context in which MPER is located within intact virions, lipo-P59 was administered in association with membrane-like micelles. Analyses showed that in this milieu, lipo-P59 had a remarkable propensity to be positioned at the membrane interface, displayed a large number of ordered structures folded in turn helices, and was as active as lipo-P59 alone at inhibiting FIV infectivity in vitro. The antibodies developed differed from the ones previously obtained by immunizing cats with the nonlipoylated version of the peptide (G. Freer, S. Giannecchini, A. Tissot, M. F. Bachmann, P. Rovero, P. F. Serres, and M. Bendinelli, Virology 322:360-369, 2004) in epitope specificity and in the fact that they bound FIV virions. However, they too lacked virus-neutralizing activity and actually enhanced FIV infectivity for lymphoid cell cultures. It is concluded that the use of MPER-reproducing oligopeptides is not a viable approach for vaccinating against FIV.

Review of dalbavancin, a novel semisynthetic lipoglycopeptide

Dalbavancin is a semisynthetic lipoglycopeptide that is derived from teicoplanin with an extended half-life that enables once-weekly dosing. It has potent in vitro activity against most gram-positive organisms, with lower minimum inhibitory concentration values than vancomycin and other investigational lipoglycopeptides. Dalbavancin is active against multi-drug-resistant pathogens such as methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci, except for strains exhibiting vanA resistance. Several Phase II and III trials have established similar efficacy and safety of dalbavancin with comparator agents in the treatment of complicated skin and skin structure infections and in catheter-related bloodstream infections. Dalbavancin may serve as an appealing alternative agent in the treatment of gram-positive infections, especially with its convenient once-weekly regimen.

[Two cases of successfully treated invasive pulmonary aspergillosis following influenza virus infection]

While invasive pulmonary aspergillosis usually occurs in immunocompromised hosts, it has been described after influenza virus infection in healthy individuals. The first case was a 76-year-old previously healthy woman admitted because of chest pain, cough, sputum, fever, and a chest radiograph abnormality. A transbronchial biopsy specimen showed fungal hyphae. Amphotericin B (AMPH) and Itraconazole (ITCZ) were given, and she improved gradually. A viral test showed a titre of 1/128 to influenza A. Case 2 was a 72-year-old previously healthy man admitted because of cough, fever, chest pain and a consolidation and cavitation on the chest radiograph. Antibiotics were ineffective. Cavitation with a halo sign appeared on the contralateral lung. Because his daughter was infected with Influenza B, we suspected he had been infected with IPA following influenza infection. AMPH and ITCZ and Micafungin sodium were given. His respiratory failure worsened, and on the tenth hospital day he required artificial ventilation; his condition improved gradually, (extubation after 40 days.) A viral test showed a titre of 1/128 to influenza B. IPA must be considered for the differential diagnosis of complications of influenza virus infection.

Comparison of Micafungin and Fluconazole for Experimental Candida Keratitis in Rabbits

PURPOSE

To evaluate the efficacy of subconjunctival injection of micafungin in the treatment of experimental Candida albicans keratitis in rabbits compared with fluconazole.

METHODS

In 1 eye of 24 New Zealand white rabbits, C. albicans (5 x 10 yeast cells) was inoculated in the corneal stroma. The animals were randomly assigned to 3 groups and received subconjunctival injection of 0.5 mL of 0.1% micafungin, 0.2% fluconazole, or physiologic saline once a day for 3 weeks. The eyes were examined slit-lamp biomicroscopically and histopathologically. The clinical course of fungal keratitis was compared among the 3 groups. In another 36 rabbits, a microbiological examination was performed using a quantitative isolate recovery technique, and the numbers of colony-forming units were compared among groups.

RESULTS

The clinical scores were significantly lower in the micafungin group than in the other 2 groups throughout the study period (P < 0.0001 approximately P = 0.0027, Bonferroni multiple comparison). The fluconazole group showed significantly lower clinical scores than the saline group on day 18 (P = 0.0343). At the end of the study period, there were significant differences between the saline and micafungin groups (P < 0.0001), the saline and fluconazole groups (P = 0.0072), and the fluconazole and micafungin groups (P = 0.0013). Histopathologically, similar results were obtained. Moreover, the results of the microbiological examination nearly matched the clinical and histopathologic findings.

CONCLUSIONS

Subconjunctival administration of micafungin was effective in the treatment of experimental Candida keratitis. Local application of micafungin to the eye would be a feasible treatment option for clinical fungal keratitis.

Impact of Pharmacometric Reviews on New Drug Approval and Labeling Decisions—a Survey of 31 New Drug Applications Submitted Between 2005 and 2006

Exploratory analyses of data pertaining to pharmacokinetic, pharmacodynamic, and disease progression are often referred to as the pharmacometrics (PM) analyses. The objective of the current report is to assess the role of PM, at the Food and Drug Administration (FDA), in drug approval and labeling decisions. We surveyed the impact of PM analyses on New Drug Applications (NDAs) reviewed over 15 months in 2005-2006. The survey focused on both the approval and labeling decisions through four perspectives: clinical pharmacology primary reviewer, their team leader, the clinical team member, and the PM reviewer. A total of 31 NDAs included a PM review component. Review of NDAs involved independent quantitative evaluation by FDA pharmacometricians. PM analyses were ranked as important in regulatory decision making in over 85% of the 31 NDAs. Case studies are presented to demonstrate the applications of PM analysis.

Relationship between the initial dose of micafungin and its efficacy in patients with candidemia

Micafungin, the first licensed echinocandin in Japan, has shown excellent in vitro and in vivo activity against all Candida species. However, the appropriate dose for the initial treatment of candidemia remains to be determined. In this study, we retrospectively examined the relationship between the clinical outcome of candidemia and the initial dose of micafungin. Patients were divided into two groups according to the initial dose of micafungin administered: group I (<2.25 mg/kg/day) and group II (>or=2.25 mg/kg/day). Micafungin produced an excellent 30-day clinical response in patients with candidemia, including Candida parapsilosis; the overall 30-day clinical response was 86%. The administration of higher doses of micafungin accelerated the clinical response and duration until the clinical response in group II was significantly shorter than that in group I (P = 0.021). However, no significant differences were observed in the 30-day mortality attributable to the fungal infection between the two groups. Considering these results, we recommend the administration of 2.25 mg/kg/day or more of micafungin in the initial treatment of patients with candidemia.

Clinical efficacy of micafungin for chronic pulmonary aspergillosis

The rising incidence of pulmonary aspergillosis is a major clinical concern. However, only a limited number of antifungal drugs are available in Japan that are effective for pulmonary Aspergillus infections. Micafungin (MCFG), a newly developed echinocandin family antifungal drug, has potent antifungal activity in vitro, but few reports detailing its clinical effectiveness have been published to date. A retrospective study was performed using data from nine patients (seven males and two females) with chronic invasive forms of pulmonary aspergillosis, who were treated with either MCFG alone or together with other antifungal drugs between April 2003 and March 2004. The overall efficacy of the treatments was evaluated in the terms of clinical, mycological, serological and radiological responses. The average age of the patients was 61.9 (20-83) years old. Four patients received only MCFG and the remaining five patients were treated with MCFG in combination with amphotericin B (AMB) only (1 patient), itraconazole (ITC) only (2 patients) or AMB backed up by ITC during AMB discontinuation periods (2 patients). The mean duration of MCFG administration was 59.2 (28-96) days. Overall, the treatment was judged to have been effective for seven of nine patients. No patient's condition deteriorated in response to treatment. Administration of MCFG alone was judged to have been effective in three of four patients. No notable adverse effects were documented during MCFG administration. These data suggest that MCFG may be an effective and safe antifungal drug for the treatment of chronic invasive forms of pulmonary aspergillosis.

Once-weekly micafungin therapy is as effective as daily therapy for disseminated candidiasis in mice with persistent neutropenia

The effect of micafungin dose scheduling on the treatment of candidemia is unknown. Neutropenic mice with disseminated Candida glabrata infection were treated with single intraperitoneal micafungin doses of 0 to 100 mg/kg of body weight and sacrificed 7 days later. The maximal decline in kidney fungal burden was 5.8 log(10) CFU/g. A 1-week pharmacokinetic-pharmacodynamic study revealed a micafungin serum half-life of 6.13 h. In mice treated with > or =50 mg/kg, there was maximal fungal decline without regrowth during the 1-week dosing interval. Next, doses associated with 34% (34% effective dose [ED(34)]) and 50% (ED(50)) of maximal kill were administered at one of three dose schedules: a single dose at t = 0, two equal doses at t = 0 and t = 3.5 days, and 7 equal doses daily. Some mice received a single dose of 100 mg/kg. Fungal burden was examined on days 1, 5, and 7. In mice treated with the ED(34), microbial kill with the daily therapy initially lagged behind the intermittent doses but exceeded it by day 7. In mice treated with the ED(50), daily and intermittent doses had equivalent day 7 effects. In mice treated with 100 mg/kg, there was no regrowth. The relative likelihoods that the area under the concentration-time curve/MIC ratio was linked to microbial kill versus peak concentration/MIC ratio or time above the MIC was 10.3 and 10,161.2, respectively. In all the experiments, no paradoxical increase in fungal burden was observed with high micafungin doses. However, only a single Candida isolate was tested. Regimens that simulated micafungin concentration-time profiles in patients treated with a single micafungin dose of 1,400 mg once a week demonstrated maximal fungal decline. Once-weekly micafungin therapy is as efficacious as daily therapy in a murine model of disseminated candidiasis.

The pharmacokinetics and safety of micafungin, a novel echinocandin, in premature infants

BACKGROUND

: Candidal fungal infection rates in neonates are increasing and are a significant cause of mortality, especially in low birth weight infants. Micafungin is an echinocandin that works by inhibiting 1,3-beta-D-glucan synthase, an enzyme responsible for fungal cell wall synthesis. The objective of this study was to determine the safety and pharmacokinetics of micafungin in premature infants.

METHODS

: This was a phase I, single-dose, multicenter, open-label, sequential-dose trial of intravenous micafungin investigating 3 doses (0.75 mg/kg, 1.5 mg/kg and 3.0 mg/kg) in 18 premature infants weighing >1000 g (n = 6 in each dosage group). A further 5 infants (500-1000 g) were enrolled in the 0.75 mg/kg dosage group only.

RESULTS

: The mean +/- standard deviation gestational age in the >1000 g dosage group was 26.4 +/- 2.4 weeks and, on entry, patients had one or more of a variety of underlying conditions, including sepsis, pneumonia and other infections caused by Candida or other species. Micafungin pharmacokinetics in preterm infants appears linear. However, premature infants >1000 g on average displayed a shorter half-life (8 hours) and a more rapid rate of clearance (approximately 39 mL/h per kg) compared with published data in older children and adults. All doses of micafungin were well tolerated and no serious drug-related adverse events were observed.

CONCLUSIONS

: Single doses of micafungin, ranging up to 3.0 mg/kg, appear well tolerated in premature infants weighing >1000 g. The drug's elimination half-life and total plasma clearance in preterm infants appear dissimilar to published values for these parameters in older children and adults. The reason(s) for this apparent difference remain to be investigated.

[Preoperative antifungal agent for pulmonary aspergilloma]

A 52-year-old man with a 6-month history of bloody sputum was admitted to our hospital. Chest X-ray on admission showed a pulmonary cavity with liquid content in the left upper field and consolidation at the circumference of the lesion. Chest computed tomography (CT) on the 13th hospital day revealed a typical fungus ball in the cavity, which we diagnosed as pulmonary aspergilloma. We administered him micafungin sodium for 1 month. Voriconazole was administered subsequently, but side effects developed. Therefore, itraconazole was administered as a substitute. Chest high-resolution CT (HRCT) clearly showed a reduction in size of the aspergilloma, thus confirming the effectiveness of antifungal agent administration in this case. However, since hemoptysis occurred for the case, left upper lobectomy was performed and postoperative course was excellent.

Steady-state pharmacokinetics of micafungin and voriconazole after separate and concomitant dosing in healthy adults

We assessed the pharmacokinetics and interactions of steady-state micafungin (Mycamine) or placebo with steady-state voriconazole in 35 volunteers. The 90% confidence intervals around the least-squares mean ratios for micafungin pharmacokinetic parameters and placebo-corrected voriconazole pharmacokinetic parameters were within the 80%-to-125% limits, indicating an absence of drug interaction.

Lipid-containing mimetics of natural triggers of innate immunity as CTL-inducing influenza vaccines

Anti-viral CD8(+) T cell responses can be induced using synthetic lipopeptides and a range of different lipid moieties have been examined in a variety of model systems and in man for this purpose. Nevertheless, only limited data exist on comparative efficacy of different lipopeptides in a single model of protection so that the optimal composition for vaccination purposes remains unknown. In this study, we examined different lipid structures from bacterial or non-bacterial sources coupled to peptides representing influenza viral epitopes recognized by CD8(+) and CD4(+) T cells. These were assessed in the context of intra-nasal (i.n.) immunization in the absence of added adjuvant. The strongest immunogens were those containing bacterially derived lipids that induced dendritic cell (DC) maturation via Toll-like receptor 2 (TLR2) binding. The number of DCs induced to mature in vitro was directly associated with the strength of the CD8(+) T cell-mediated viral clearing responses in primed mice. Mice immunized with the TLR2-binding lipopeptides showed greatly enhanced numbers of specific IFN-gamma-secreting CD8(+) T cells at the site of infection after i.n. exposure to virus, which resulted in enhanced protection of the pneumonic lung. Importantly, lipopeptide-pulsed DCs were able to induce the appropriate T cells, indicating that the self-adjuvanting effects could occur in the absence of free lipopeptide interacting with additional TLR2-bearing cells in vivo. This study defines a hierarchy of lipopeptide constructs that can program DC to prime memory CD8(+) T cells that on recall function to clear influenza virus from the infected lung.

Concomitant cyclosporine and micafungin pharmacokinetics in healthy volunteers

Cyclosporine is a marketed immunosuppressive agent and a known substrate for CYP3A. Micafungin is an antifungal agent and a mild inhibitor of CYP3A-mediated metabolism in vitro. The objectives of this study were to evaluate the pharmacokinetics of cyclosporine and micafungin before and with concomitant administration. The pharmacokinetics of single-dose oral cyclosporine (5 mg/kg) were estimated on days 1, 9, and 15 (n = 27). Subjects received micafungin (100 mg/d over 1 hour) on days 7, 9, and 11 through 15. Micafungin pharmacokinetics were estimated on days 7, 9, and 15. Mean apparent oral cyclosporine clearances were estimated to be 645+/-236 mL/h/kg, 546+/-101 mL/h/kg (P = .01), and 540+/-104 mL/h/kg (P = .02) for days 1, 9, and 15, respectively. Micafungin appears to be a mild inhibitor of cyclosporine metabolism.

Intranasal immunization using biphasic lipid vesicles as delivery systems for OmlA bacterial protein antigen and CpG oligonucleotides adjuvant in a mouse model

The nasal mucosa is an important arm of the mucosal system since it is often the first point of contact for inhaled antigens. The ineffectiveness of the simple delivery of soluble antigens to mucosal membranes for immunization has stimulated extensive studies in appropriate delivery systems and adjuvants. We have evaluated biphasic lipid vesicles as a novel intranasal (i.n.) delivery system (designated as vaccine targeting adjuvant, VTA) containing bacterial antigens and CpG oligodeoxynucleotides (ODNs). Results show that administration of antigen and CpG ODNs in biphasic lipid vesicles resulted in greater induction of IgA levels in serum (P< 0.05) and mucosal antibody responses such as IgA in nasal secretions and lung (P< 0.01) after immunization with a combined subcutaneous (s.c.)/i.n. as compared to s.c./s.c. approach. Based on antibody responses, VTA formulations were found to be suitable as delivery systems for antigens and CpG ODNs by the intranasal route, resulting in a Th2-type of immune response, characterized by IgG1 and IL-4 production at the systemic level.

Intranasal Vaccination with a Lipopeptide Containing a Conformationally Constrained Conserved Minimal Peptide, a Universal T Cell Epitope, and a Self‐Adjuvanting Lipid Protects Mice from Group A Streptococcus Challenge and Reduces Throat Colonization

Infection with group A streptococcus (GAS) may result in a number of human diseases, including potentially life-threatening postinfectious sequelae. In the present study, J14, a conformationally constrained conserved minimal peptide from the M protein, was incorporated into a lipopeptide construct to which a universal T cell epitope and a self-adjuvanting lipid moiety, Pam(2)Cys, were also attached. We demonstrate that this lipopeptide construct, when administered intranasally (inl) without additional adjuvants, protects outbred mice from lethal respiratory GAS challenge. In addition, the lipopeptide was capable of inducing J14-specific mucosal immunoglobulin A, which coincided with reduced throat colonization after respiratory GAS challenge. These preclinical experiments show that this lipopeptide could form the basis of an antidisease and transmission-blocking inl GAS vaccine.

Comparison of lipopeptide-based immunocontraceptive vaccines containing different lipid groups

We have previously shown that incorporating the lipid moiety dipalmitoyl-S-glyceryl cysteine (Pam2Cys) into peptide structures effectively adjuvants otherwise weak immunogens. In this study lipopeptides based on luteinising hormone releasing hormone (LHRH) as a B cell epitope, [B], were synthesised in tandem with a 17-residue T-helper epitope, [T], derived from the fusion protein of the morbillivirus canine distemper virus. In this way vaccine candidates with the structure [T]-[B] were produced. These peptides were then lipidated with different diacylated moieties. The acyl moieties used were: palmitic acid (C16) to give Pam2Cys, stearic acid (C18) to give Ste2Cys, lauric acid (C12) to give Lau2Cys and octanoic acid (C8) to give Oct2Cys. We compared the immunogenicities of these simple lipopeptides in BALB/c mice by measuring their ability to induce anti-LHRH antibodies and found that immunogenicity was dependent on the length of the alkane chains of the incorporated lipid moieties with the hierarchy C16=C18>C12>C8. The antibody levels elicited by the lipopeptides also correlated with their ability to inhibit the reproductive capability of female mice in fertility trials. Furthermore, the C16 lipopeptide was the most effective in activating dendritic cells, measured by up regulation of surface MHC Class II molecules, and also in activating NF-kappaB in a Toll-like receptor-2 (TLR2)-dependent manner.

Immunogenicity of Liposomes Containing Lipid Core Peptides and the Adjuvant Quil A

PURPOSE

The purpose of this study was to investigate the immunogenicity of liposomes containing mannosylated lipid core peptide (manLCP) constructs, both in vitro and in vivo, with or without the addition of the immune stimulating adjuvant Quil A.

METHODS

Mouse bone marrow dendritic cells (BMDC) were cultured with liposome formulations for 48 h, and the resulting level of BMDC activation was determined by flow cytometry. BMDC pulsed with liposome formulations were incubated with 5,6-carboxyfluoroscein diacetate succinimidyl ester-labeled T cells for 72 h and the resulting T cell proliferation was determined by flow cytometry. To investigate the immunogenicity of formulations in vivo, groups of C57Bl/6J mice were immunized by subcutaneous injection, and the resulting antigen-specific cytotoxic and protective immune responses toward tumor challenge evaluated.

RESULTS

Despite being unable to demonstrate the activation of BMDC, BMDC pulsed with liposomes containing manLCP constructs were able to stimulate the proliferation of naïve T cells in vitro. However, in vivo only liposomes containing both manLCP and Quil A were able to stimulate a strong antigen-specific cytotoxic immune response. Liposomes containing manLCP and Quil A within the same particle were able to protect against the growth of tumor cells to a similar level as if the antigen was administered in alum with CD4 help.

CONCLUSION

ManLCPs administered in liposomes are able to stimulate strong cytotoxic and protective immune responses if Quil A is also incorporated as an adjuvant.

[Micafungin therapy for a case of chronic necrotizing pulmonary aspergillosis]

The patient was a 42-year-old man who visited a physician with fever, and was diagnosed with pulmonary abscess. Antibiotic therapy was ineffective, and he was referred to our hospital. Chest CT scanning revealed a lesion with cavity formation with an infiltrative shadow in the right upper lobe, and another infiltrative shadow in the left upper lobe. Chronic necrotizing pulmonary aspergillosis (CNPA) was diagnosed on the basis of positive culture of bronchial lavage specimens and positive serological test results for Aspergillus, in addition to the clinical and radiographic features. Intravenous administration of micafungin (MCFG) was initiated with combination therapy of percutaneous cavity drainage, inhaled amphotericin B and oral itraconazole. Clinical symptoms and findings gradually improved, and he was discharged after 40 days of MCFG therapy. MCFG was safe and effective therapy in this case, and may be considered a new therapeutic option for CNPA.

Aggravated infection in mice co-administered with Mycobacterium tuberculosis and the 27-kDa lipoprotein

We have previously reported that mice immunized with the mycobacterial 27-kDa lipoprotein were more susceptible to Mycobacterium tuberculosis (Mtb) challenge. We also showed that 27-kDa lipoprotein abrogated the protection afforded by the BCG vaccine when administrated together, suggesting that the 27-kDa lipoprotein may modulate the course of experimental mycobacterial infection. In this study, we address the role of the 27-kDa lipoprotein in modulating the immune response to mycobacteria. Our results show that co-administration of BALB/c mice with Mtb and the 27-kDa lipoprotein (Mtb+27kDa), but not its non-acylated form, increases the susceptibility of mice to Mtb infection. Significantly lower DTH reaction and splenocyte proliferation to PPD stimulation were also observed in Mtb+27kDa-infected mice compared to Mtb-infected mice. Furthermore, during infection, splenocytes and purified T cells lost their ability to proliferate in response to concanavalin A stimulation more rapidly in the Mtb+27kDa-infected mice, which was accompanied by high IFN-gamma and NO production, but low TNF-alpha secretion levels. Addition of L-NMMA, anti-IFN-gamma and anti-TNF-alpha antibodies restored in vitro proliferative responses of T cells from Mtb+27kDa-infected mice. Short-term L-NMMA treatment of Mtb+27kDa-infected mice prevented the 27-kDa-mediated immunosuppression and increase in susceptibility to Mtb. Altogether, these data suggest that the 27-kDa lipoprotein plays a role in Mtb infection by inducing increased suppression of the immune response due to elevated NO production.

Pharmacokinetics-pharmacodynamics of micafungin in Japanese patients with deep-seated mycosis

The objective of this study was to describe the pharmacokinetic profile and investigate the effective concentration of micafungin in Japanese male patients with deep-seated mycosis. 66 patients were treated with i.v. micafungin 12.5-150 mg intravenously for up to 56 days. At this dose range, micafungin showed linear pharmacokinetics, and the mean values of Cmax and Cmin amounted to 3.16-12.9 microg/mL and 0.70-3.68 microg/mL, respectively. The mean value for the elimination half-life was 13.5 h (95 samples from 65 patients), and it remained almost constant over the dose range. In addition, the elimination half-life was not influenced by age, gender or weight, and was similar to that found in healthy subjects. The active metabolites M1 and M2 were detectable, but their exposure was lower than that of the unchanged drug. The pharmacokinetic-pharmacodynamics ob micafungin were then investigated. The overall clinical response rate against aspergillosis and candidiasis showed good results at a dose of 50 mg and over. The Cmax and Cmin at the latter dose amounted to 5.16 and 1.41 microg/mL, respectively. In conclusion, micafungin showed linear pharmacokinetics at doses ranging from 12.5 to 150 mg, and the effective concentration was considered to be over 5 microg/mL as maximum level in Japanese patients with deep-seated mycosis such as candidiasis and aspergillosis.

A study to determine the safety profile and maximum tolerated dose of micafungin (FK463) in patients undergoing haematopoietic stem cell transplantation

This open-label, dose-escalation study assessed the maximum tolerated dose (MTD) of the new antifungal micafungin in patients undergoing haematopoietic stem cell transplantation (HSCT). Participants received 3, 4, 6 or 8 mg/kg/day micafungin intravenously from 7 days to a maximum of 28 days or until neutropaenia resolved. The MTD was defined as the highest dose not causing the same Grade 3 or 4 adverse event in three or more patients. All 36 participants received >/=8 days treatment for a median of 18 days (range: 8-28); 1 patient withdrew consent and a further 11 discontinued to receive another systemic antifungal agent for a suspected infection. No case of confirmed invasive fungal infection occurred. Adverse events were those expected for patients undergoing HSCT and showed no evidence of dose-related toxicity. Criteria for MTD were not met; no patient had a Grade 3 or 4 adverse event considered causally related to micafungin. Thus, the MTD of micafungin can be inferred to be 8 mg/kg/day or higher.

Micafungin (FK463), alone or in combination with other systemic antifungal agents, for the treatment of acute invasive aspergillosis

BACKGROUND

Micafungin (FK463) is a new lipopeptide compound (echinocandin) with activity against Aspergillus and Candida species. This study evaluated the safety and efficacy of micafungin in patients with proven or probable invasive aspergillosis (IA).

METHODS

A multinational, non-comparative study was conducted to examine proven or probable (pulmonary only) Aspergillus species infection in a wide variety of patient populations. The study employed an open-label design utilizing micafungin alone or in combination with another systemic antifungal agent. Criteria for IA and therapeutic responses were judged by an independent panel.

RESULTS

Of the 331 patients enrolled, only 225 met diagnostic criteria for IA as determined by the independent panel and received at least one dose of micafungin. Patients included 98/225 who had undergone hematopoietic stem cell transplantation (HSCT) (88/98 allogeneic), 48 with graft versus host disease (GVHD), and 83/225 who had received chemotherapy for hematologic malignancy. A favorable response rate at the end of therapy was seen in 35.6% (80/225) of patients. Of those only treated with micafungin, favorable responses were seen in 6/12 (50%) of the primary and 9/22 (40.9%) of the salvage therapy group, with corresponding numbers in the combination treatment groups of 5/17 (29.4%) and 60/174 (34.5%) of the primary and salvage treatment groups, respectively. Of the 326 micafungin-treated patients, 183 (56.1%) died during therapy or in the 6-week follow-up phase; 107 (58.5%) deaths were attributable to IA.

CONCLUSIONS

Micafungin as primary or salvage therapy proved efficacious and safe in high-risk patients with IA, although patient numbers are small in the micafungin-only groups.

Clinical safety of HIV lipopeptides used as vaccines in healthy volunteers and HIV-infected adults

BACKGROUND

HIV-1 lipopeptides have been developed by the French National Agency for AIDS Research (ANRS) for use as candidate vaccine against HIV since 1994. Between 1996 and 2005, four different lipopeptide constructs were tested alone or in combination with recombinant canarypox HIV vaccines in 10 trials conducted in France. The aim of this study was to review clinical safety of HIV lipopeptides.

METHODS

A meta-analysis based on individual subject data examined clinical safety data collected in eight preventive trials and two therapeutic trials enrolling 200 HIV-1-uninfected healthy volunteers and 48 HIV-1-infected patients.

RESULTS

Of 248 trial participants, eight (3.2%) did not complete follow-up: seven among the 200 healthy volunteers, and one among the 48 HIV-1 infected patients. During the 354 person-years of follow-up, 860 lipopeptides injections were administered. Local reactions were common. However, in trials where lipopeptides were tested without adjuvant and appropriate diluents, none of the vaccinees experienced severe local response. Systemic reactions were generally mild and transient. No grade 4 reaction was reported; 18 subjects experienced grade 3 systemic events related to the vaccination, mainly asthenia, fever, headache and arthralgia. Multivariate analysis showed that female sex, number of injections and diluent (more reactions in 5% glucose alone than in combination with Tris-HCl buffer) significantly increased systemic reactions related to the vaccination.

CONCLUSION

These data demonstrate that reactogenicity and systemic safety of HIV lipopeptides vaccine are acceptable both in healthy volunteers and HIV-infected adults.

Intranasal lipopeptide primes lung-resident memory CD8+ T cells for long-term pulmonary protection against influenza

The longevity of the influenza virus-specific CD8+ T cell response following intranasal delivery of a synthetic lipopeptide was investigated and the characteristics and location of the cells associated with viral clearance examined. The lipopeptide, incorporating an epitope for CD8+ T cells and another for CD4+ T cells with the lipid moiety S-[2,3-bis(palmitoyloxy)propyl]cysteine (Pam2Cys) attached, induced potent and long-lived pulmonary protection. Both the lipopeptide and its largely unprotective non-lipidated counterpart elicited comparable numbers of CD8+ T cells in the spleen, which was the main location of the memory pool. However, the lipopeptide, unlike the non-lipidated peptide, also induced a substantial memory population that remained in the lungs and was rapidly activated upon viral challenge months later. These lipopeptide-induced lung-resident CD8+ T cells were also very similar in number and IFN-gamma-secreting potential to those induced by prior exposure to the virus itself and are likely mediators of initial viral clearance prior to recruitment from the expanding lymph node T cell pool. Significant clearing responses were demonstrated as late as 9 months post-lipopeptide vaccination. This study shows that CD8+ T cells primed by the lipopeptide are not only long-lived but can take up residence in the lung where they are important early mediators of pulmonary protection.