Biomedical subjects

S P Richieri

Publications and source records attributed to S P Richieri.

At least 19 recordsLinked to original sources

PubMed1999

Phenotypic analysis of human immunodeficiency virus (HIV) type 1 cell-mediated immune responses after treatment with an HIV-1 immunogen.

It was hypothesized that immune recognition could be stimulated with combined immune-based and potent antiviral drug therapies. This study examined human immunodeficiency virus type 1 (HIV-1)-specific lymphocyte proliferation before and after treatment with an inactivated HIV-1 immunogen in 15 chronically infected HIV-1 seropositive subjects. Lymphocyte proliferation to the immunizing antigen (gp120-depleted HIV-1; P<.001), purified native p24 (P<.001), and recombinant p24 (P<.05) increased after treatment with the HIV-specific immune-based therapy. By HIV-1 antigen-specific flow cytometry, T helper CD4 lymphocytes, CD8 lymphocytes, and NK cells (all P<.001) were the predominant cell types proliferating in vitro after treatment. Additional phenotyping of proliferating cells revealed predominantly CD4 and CD8 memory (both P<.001) phenotypes. This study supports the concept that in vitro lymphocyte proliferation to HIV-1 antigens, augmented after treatment with an inactivated HIV-1 immunogen, involves primarily CD4 and CD8 cell memory immune responses.

AIDS Vaccines↗

PubMed1998

T cell receptor peptide vaccination in rheumatoid arthritis: a placebo-controlled trial using a combination of Vbeta3, Vbeta14, and Vbeta17 peptides.

OBJECTIVE: Restricted T cell receptor (TCR) gene usage has been demonstrated in animal models of autoimmune disease and has resulted in the successful use of TCR peptide therapy in animal studies. This clinical trial was undertaken to determine the safety and efficacy of a combination of Vbeta3, Vbeta14, and Vbeta17 TCR peptides in Freund's incomplete adjuvant (IFA) in patients with rheumatoid arthritis (RA). METHODS: A double-blind, placebo-controlled, multicenter, phase II clinical trial was undertaken using IR501 therapeutic vaccine, which consists of a combination of 3 peptides derived from TCRs (Vbeta3, Vbeta14, and Vbeta17) in IFA. A total of 99 patients with active RA received either 90 microg (n = 31) or 300 microg (n = 35) of IR501 or IFA alone (n = 33) as a control. The study medication and placebo were administered as a single intramuscular injection (1 ml) at weeks 0, 4, 8, and 20. RESULTS: Treatment with IR501 was safe and well tolerated. None of the patients discontinued the trial because of treatment-related adverse events. Efficacy was measured according to the American College of Rheumatology 20% improvement criteria. Using these criteria, patients in both IR501 dosage groups showed improvement in disease activity. In the most conservative analysis used to evaluate efficacy, an intent-to-treat analysis including all patients who enrolled, the 90-microg dosage group showed a statistically significant improvement compared with control patients at the 20-week time point after the third injection. Trends toward improvement were shown in both the 90-microg and the 300-microg dosage groups at week 24 after the fourth injection. CONCLUSION: IR501 therapeutic vaccine therapy was safe and well tolerated, immunogenic, and demonstrated clinical improvement in RA patients. Additional clinical trials are planned to confirm and extend these observations.

Adult↗

PubMed1998

Whole-killed gp120-depleted HIV-1 antigen in a murine model for prophylactic vaccination.

In this study, the effects were examined of dose and adjuvant of whole-killed gp120-depleted HIV-1 antigen on antibody and cytokine responses in a murine model. Immunization with increasing doses of inactivated HIV-1 antigen in Incomplete Freund's Adjuvant (IFA) resulted in increased production of IL-4 and IgG1 antibody with decreased production of interferon gamma. Immunization with inactivated HIV-1 antigen in Detox PC adjuvant produced TH1 type predominant cytokine patterns along with IgG2a subclass antibody. Higher levels of interferon gamma were associated with immunization with inactivated HIV-1 antigen in Detox PC compared with inactivated HIV-1 in IFA or inactivated HIV-1 in saline. Inactivated HIV-1 antigen in Detox PC adjuvant produced a trend of lower levels of the beta-chemokine MIP-1 alpha compared with inactivated HIV-1 in IFA or saline. Dose and adjuvant play an important role in the type of immune response elicited to a whole-killed HIV vaccine. Low doses of inactivated HIV-1 antigen in Detox PC adjuvant are currently being studied in animal models in order to optimize cell-mediated immunity against HIV infection.

AIDS Vaccines↗

PubMed1998

In vitro p24 antigen-stimulated lymphocyte proliferation and beta-chemokine production in human immunodeficiency virus type 1 (HIV-1)-seropositive subjects after immunization with an inactivated gp120-depleted HIV-1 immunogen (Remune).

We examined the effect of immune stimulation by a human immunodeficiency virus type 1 (HIV-1) immunogen (Remune) compared to a non-HIV vaccine (influenza) on HIV-1-specific immune responses in HIV-1-seropositive subjects. HIV-1 p24 antigen-stimulated lymphocyte proliferation was not augmented after immunization with the influenza vaccine. In contrast, subjects increased their lymphocyte proliferative responses to p24 antigen after one immunization with HIV-1 immunogen (Remune) (gp120-depleted inactivated HIV-1 in incomplete Freund's adjuvant). Furthermore, p24 antigen-stimulated beta-chemokine production (RANTES, MIP-1alpha, MIP-1beta) was also augmented after immunization with the HIV-1 immunogen but not influenza vaccine. Taken together, these results suggest that in this cohort, HIV-specific immune responses to p24 antigen can be augmented after immunization with an HIV-1 immunogen. The ability to upregulate immune responses to the more conserved core proteins may have important implications in the development of immunotherapeutic interventions for HIV-1 infection.

AIDS Vaccines↗

PubMed1998

A primer on HIV type 1-specific immune function and REMUNE.

The ability to recognize HIV antigens is lost early in HIV-1 infection. Individuals with nonprogressive HIV disease have been observed to mount strong immune responses against the virus and have become a paradigm to emulate with immune-based therapies. Highly active antiviral drug therapy (HAART) has now become the standard of care for HIV-1-infected individuals. Because HIV-specific anergy occurs early in HIV infection, HAART initiated after primary infection may not reconstitute HIV-specific immune function. We have been investigating the effects of an immune-based therapy, called REMUNE, in HIV-1-seropositive individuals. REMUNE has been observed to stimulate HIV-1-specific immune function measured by delayed-type hypersensitivity, lymphocyte proliferation, Th1 cytokine, and beta-chemokine production. Multiple Phase II studies and a Phase III clinical end-point study are ongoing in thousands of seropositive individuals in order to test the clinical utility of REMUNE. The clinical testing of REMUNE and other promising immune-based therapies may provide additional treatment modalities useful in the chronic management of HIV-1.

AIDS Vaccines↗

PubMed1997

Effect of immunization with an inactivated gp120-depleted HIV-1 immunogen on beta-chemokine and cytokine production in subjects with HIV-1 infection.

OBJECTIVE: To measure beta-chemokine and cytokine production in HIV-1-infected subjects undergoing treatment with HIV-1 immunogen (REMUNE). DESIGN: Open label treatment study. METHODS: beta-Chemokine and cytokine production in peripheral blood mononuclear cell (PBMC) culture. RESULTS: Interferon-gamma production (p = 0.04) and lymphocyte proliferation (p = 0.001) to HIV-1 antigen-stimulated PBMCs increased after immunization with the HIV-1 immunogen. A correlation was demonstrated after immunization between HIV-1 antigen-stimulated lymphocyte proliferation and interferon-gamma levels (r = 0.53, p = 0.04). No significant change after immunization was seen for interleukin-4 production. A significant increase in mean levels of HIV-1 antigen-stimulated RANTES (i.e., regulated upon, activation normal T-cell expressed and secreted), was evident 1 month after immunization (p = 0.002) and remained elevated 3 months after immunization. RANTES production was decreased in CD8-depleted PBMC cultures. Mean serum HIV-1 RNA copy numbers and CD4 cell counts remained stable after immunization (p > 0.5). A correlation was demonstrated between HIV-1 antigen-stimulated interferon-gamma and RANTES production (r = 0.54, p = 0.002). CONCLUSIONS: This report describes an augmentation of beta-chemokines and TH1-type cytokines from PBMCs after immunization with the HIV-1 immunogen.

CD4 Lymphocyte Count↗

PubMed1997

Results of a phase I clinical trial of a T-cell receptor vaccine in patients with multiple sclerosis. II. Comparative analysis of TCR utilization in CSF T-cell populations before and after vaccination with a TCRV beta 6 CDR2 peptide.

We report here the results of a phase I trial of a T-cell receptor (TCR) V beta 6 CDR2 region peptide vaccine in 10 patients with multiple sclerosis who showed biased over-representations of V beta 6 mRNA among T-cells in their cerebrospinal fluids (CSF). One group of 5 patients was immunized twice during a four week period with 100 micrograms of the TCRV beta 6 peptide 39-LGQGPEF LTYFQNEAQLEKS-58 emulsified in incomplete Freund's adjuvant (IFA); the second group of 5 MS patients received 300 micrograms of the same peptide in IFA over a similar time period. Patients were monitored for adverse events, immunogenicity of the peptide and changes in their CSF T-cell populations. The results indicate that this peptide was immunogenic (T-cell proliferation assays and recall DTH responses) in some of the patients, although none of the immunized patients produced detectable anti-peptide antibodies. More importantly, we show that the 5 patients treated with higher doses of the vaccine displayed a slight decrease in CSF cellularity, a lack of growth of CSF cells in cytokine supplemented expansion cultures that implies a significant absence of a subset of activated CD4 T-cells and a marked diminution in V beta 6 mRNA levels among T-cells in these cultures. By comparison, in 5 patients receiving the lower dosage of the vaccine, CSF cellularity was the same or slightly increased over pre-vaccination levels, CSF cells from 1 patient failed to grow in expansion cultures and cultured CSF cells from 2 patients underwent a change from an oligoclonal V beta 6 pattern to one that was more polyclonal. These results justify a more through exploration of the use of TCR peptide vaccines as a possible therapeutic treatment for MS.

Adult↗

PubMed1997

Cross-clade immune responses after immunization with a whole-killed gp120-depleted human immunodeficiency virus type-1 immunogen in incomplete Freund's adjuvant (HIV-1 immunogen, REMUNE) in human immunodeficiency virus type-1 seropositive subjects.

Lymphocyte proliferation responses to gp120-depleted HZ321 virus (clade A) antigen were compared to BAL human immunodeficiency virus (HIV) virus antigen (clade B) responses, clade E HIV virus antigen responses, and purified native p24 antigen responses in 15 human immunodeficiency virus type-1 (HIV-1) seropositive subjects immunized with a whole-killed inactivated gp120-depleted HIV-1 antigen in Incomplete Freund's adjuvant (HIV-1 immunogen, REMUNE). A significant increase in lymphocyte proliferation to HZ321 antigen was observed after immunization with the HIV-1 immunogen (p = 0.02). A strong association was demonstrated between the HIV-1 immunizing antigen, HZ321, and native p24 antigen responses (r = 0.80, p < 0.0001). Furthermore, a strong association in terms of proliferative responses was demonstrated between HZ321 virus (clade A) responses and BAL virus (clade B) (r = 0.95, p < 0.0001) and clade E virus antigen (r = 0.92, p < 0.0001). Proliferative responses to HIV antigens also correlated with baseline CD4 counts. Taken together, these results support the specificity of immune responses induced by REMUNE (HIV-1 immunogen). The development of cross-reactive immune responses between clades and to the more conserved epitopes of the virus have implications in the development of therapeutic and prophylactic HIV vaccines.

AIDS Vaccines↗

PubMed1996

Initial studies on active immunization of HIV-infected subjects using a gp120-depleted HIV-1 Immunogen: long-term follow-up.

In 1987, exploratory clinical studies were initiated to determine whether the development of AIDS in HIV-infected individuals might be delayed or prevented by immunization with an inactivated HIV preparation. Preclinical studies had shown the preparation to be safe and immunogenic. Twenty-three patients with biopsy-confirmed persistent generalized lymphadenopathy (CDC III) and two with asymptomatic HIV infection and CD4 lymphocyte counts between 135 and 769/mm3 were studied, of whom eight (32%) had additional HIV-related symptoms. Over a 3-year period, they received a median of eight open-label inoculations of 100 micrograms of inactivated gp 120-depleted HIV-1 Immunogen in incomplete Freund's adjuvant (IFA). Clinical, general laboratory, immunologic, and virologic parameters were followed for up to 6 years. No serious treatment-related adverse experiences were reported, nor was accelerated HIV disease progression seen. Twelve patients developed a delayed-type hypersensitivity response (HIV-DTH) to the immunogen and nine showed fourfold or greater increases in anti-p24 antibody titers. In the follow-up period, 10 of the 25 patients developed AIDS and one with Kaposi's sarcoma (KS) at baseline progressed. Of the 12 patients who became HIV-DTH-responsive, one developed an opportunistic infection (OI), occurring approximately 5 years from study onset, and subsequently died. One additional HIV-DTH responder developed KS. Of the 13 patients who remained HIV-DTH-nonresponsive, nine (69%) progressed to AIDS and seven of these have died. Differences were also observed in terms of HIV-DNA copy number, CD4 percentages, and anti-p24 antibody patterns between the HIV-DTH-responsive and -nonresponsive groups, suggesting a more favorable clinical course in the former. HIV-1 Immunogen in IFA appears to be safe and immunogenic. Further studies are indicated to determine clinical efficacy of the HIV Immunogen as well as the significance of the apparent correlation between HIV-DTH responsivity and a more favorable clinical course.

AIDS Vaccines↗

PubMed1996

Viral load, CD4 percentage, and delayed-type hypersensitivity in subjects receiving the HIV-1 immunogen and antiviral drug therapy.

Two trials of subjects inoculated with the inactivated, gp120-depleted HIV-1 Immunogen are reported. In one study, in which 19 subjects received ZDV and 8 subjects received ddI, treatment with the HIV-1 Immunogen did not affect the pharmacokinetic parameters of the antiviral drugs. In another study, 65 subjects who were previously immunized with the HIV-1 Immunogen over a mean period of 4.0 years (range, 1.2-5.4 years) received inoculations at 0 and 6 months. At some point during this 48-week study, 72% of the subjects (47/65) were receiving antiviral drug therapy. The HIV-1 DNA load in CD4 cells and CD4 percentage were found to be stable over the 48-week period. Delayed-type hypersensitivity to HIV-1 antigens increased after two inoculations with the HIV-1 Immunogen. In these two trials, no serious treatment-related adverse events were documented in the subjects. The two studies presented herein are the first to suggest that an immune-based therapy such as the HIV-1 Immunogen can be combined safely with antiviral drugs, supporting further study to evaluate the clinical utility of this approach.

AIDS Vaccines↗

PubMed1996

Combination therapies against HIV-1 infection: exploring the concept of combining antiretroviral drug treatments with HIV-1 immune-based therapies in asymptomatic individuals.

The deleterious effect of HIV on the immune system begins at the time of infection. At seroconversion the virologic and immunologic factors that ultimately will dictate the rate of disease progression are believed to be already in place. The concept developed in this paper implies that, to impact significantly on the progression of disease, anti-HIV therapies should be initiated as early as possible in asymptomatic individuals. Published results have shown that combination drug therapies are potent in reducing HIV-1 RNA load in plasma in asymptomatic individuals, and that some HIV-1 immune-based therapies have a positive impact on immunological markers of disease progression, including HIV-1 cell-mediated immunity (CMI) and CD4 percent. The strategy discussed is to test a combination of antiretroviral therapy with HIV-1 immune-based therapy, such as the inactivated HIV-1 immunogen preparation, in asymptomatic individuals. The goal of this combination approach is to overcome the limitations of each therapy alone. Preliminary data suggest that antiretroviral therapy and the HIV-1 Immunogen can be combined with no noticeable interference and/or added toxicity in a broad range of HIV-1-infected individuals. Combining both therapies may enhance and expand the impact on key surrogate markers of disease progression, although they likely achieve this impact through different mechanisms. Thus, the primary question remains: Can these effects be synergistic?

Adjuvants, Immunologic↗

PubMed1996

V beta 17 T cell receptor peptide vaccination in rheumatoid arthritis: results of phase I dose escalation study.

OBJECTIVE: To determine whether modulation of activated T cells occurs in patients with rheumatoid arthritis (RA) after immunization with T cell receptor (TCR) V beta 17 peptides, a phase I trial was initiated to investigate the safety and feasibility of TCR peptide immunization as a therapeutic approach in RA. METHODS: 15 patients with moderate to severe RA were given an intramuscular injection of one of 4 doses (10, 30, 100, and 300 micrograms) of the V beta 17 peptide vaccination, followed by a booster injection of the same dose of vaccine 3 weeks later. Patients were followed for 48 weeks. RESULTS: The product was well tolerated and no serious adverse events attributable to the vaccine were observed. This was an uncontrolled phase I trial, however; decreases in patients joint scores were observed at all followup visits starting at 4 weeks after primary immunization. Activated V beta 17 T cells (IL-2R+) in peripheral blood were decreased (> or = 20%) in 3/5 patients in the 100 micrograms group after initial measurement at Week 2 and 3/4 patients in the 300 micrograms group 3 weeks after immunization. Lymphocyte proliferation in response to the V beta 17 peptide was detected at 6 weeks or later after primary inoculation in 6/15 patients (40%) immunized. CONCLUSION: Further controlled studies are required to assess the biologic and clinical efficacy of this treatment approach.

Adult↗

PubMed1995

Viral load in peripheral blood mononuclear cells as surrogate for clinical progression.

During the symposium on surrogate markers of HIV, the Scientific Advisory Committee posed the following question: "Which surrogate markers currently deserve the greatest commitment of investigative resources to validate them in a clinical setting?" The Committee concluded that for antiretroviral drugs measurements of HIV RNA in plasma deserve the greatest priority, and for immune-based therapies assessing viral load still had the highest priority. But it was recognized that assessing viral load should not be restricted to plasma RNA because the primary mechanisms of action are different from antiretroviral drugs. Thus, the Committee voted that based on current knowledge, investigating the clinical relevance of changes in HIV-1 DNA and RNA copy number in peripheral blood mononuclear cells (PBMCs) with validated assays should be given equal focus for immune-based therapies. This article reviews the rationale for using HIV-1 DNA and RNA load in PBMCs for the monitoring of clinical trials and presents recent data that indicate that the postseroconversion level and the dissemination of proviral DNA in the blood cells have prognostic value, i.e., high levels correlate with disease progression. In addition, longitudinal studies show that an increase in proviral DNA and/or HIV mRNA load correlates with disease progression. We present evidence that these markers are relevant activity markers for anti-HIV therapies. Changes in both DNA and RNA load can be achieved using either antiretroviral drugs or immune-based therapies. These results suggest that these markers should be evaluated in clinical studies to firmly establish their value as surrogates of clinical progression.

Biomarkers↗

PubMed1994

Effect of immunization with inactivated gp120-depleted human immunodeficiency virus type 1 (HIV-1) immunogen on HIV-1 immunity, viral DNA, and percentage of CD4 cells.

A 1-year study measured the effect of administration of an inactivated human immunodeficiency virus type 1 (HIV-1) immunogen in incomplete Freund's adjuvant (IFA) on HIV-1-specific immunity and viral burden in asymptomatic HIV-1-infected patients. A total of 103 patients were enrolled in this double-blind, randomized study comparing immunogen in adjuvant with adjuvant alone. This study was conducted at nine medical centers throughout the United States. Significant differences in cell-mediated immune responses to HIV-1 and p24 core antigen were observed between the treated and control groups (P < .01). Compared with controls, treated patients as a group had a significantly lower rate of increase in viral DNA as determined by quantitative HIV-1 DNA-polymerase chain reaction (P = .016). Significant differences in the rate of percent CD4 cell decline were also observed between the 2 groups (P = .024). These data suggest that augmentation of HIV-1-specific immunity via immunotherapy may alter the rate of increase of HIV-1 DNA in peripheral blood mononuclear cells and stabilize the percent of CD4 cell decline in relatively healthy HIV-1-infected persons.

AIDS Vaccines↗

PubMed1994

Inactivated HIV-1 Immunogen: impact on markers of disease progression.

The pursuit of valid markers of disease progression in human immunodeficiency virus type 1 (HIV-1) infection is especially relevant considering the potential treatment alternatives that presently are under evaluation. Because HIV-1 infection results in a virally induced immune suppression characterized by the loss of cell-mediated immunity (CMI), depletion of CD4+ cells, loss of core antibody, and an increase in viral burden, these markers seemed to be appropriate to monitor in a controlled study. We monitored a number of virologic, immunologic, and cytologic markers of disease progression in 103 subjects who were enrolled in a 12-month, double-blind, randomized, adjuvant-controlled study of the HIV-1 inactivated Immunogen. The markers included HIV-1 DNA, HIV-1 RNA, CD4 percent, p24 antibody, and lymphocyte proliferation. Analysis of HIV-1 DNA with a quantitatively polymerase chain reaction (PCR) assay indicated a treatment effect on viral burden in the HIV-1 Immunogen-treated group. Analysis of HIV-1 RNA revealed a similar trend favoring the Immunogen-treated group. In addition, a significant effect was shown on CD4 percent and CMI in the Immunogen-treated group. An analysis of CMI that used stimulation indices underrepresented the immunogenicity of the Immunogen. Further examination revealed that the lymphocytes of the HIV-1 Immunogen-treated patients were proliferating in vitro without exogenous antigen. Although the clinical significance of this phenomenon currently is unknown, it may be a relevant prognostic marker for assessment of HIV-1 therapy. The data presented here support the concept that immunotherapy with the HIV-1 Immunogen may slow disease progression.(ABSTRACT TRUNCATED AT 250 WORDS)

AIDS Vaccines↗

PubMed1993

Development and validation of a polymerase chain reaction method for the precise quantitation of HIV-1 DNA in blood cells from subjects undergoing a 1-year immunotherapeutic treatment.

OBJECTIVE: To validate a quantitative polymerase chain reaction method developed to measure HIV-1 DNA in peripheral blood mononuclear cells. DESIGN: The assay was used to measure HIV-1 DNA in 15 consecutive blood samples taken from subjects enrolled in a multicenter, randomly allocated, double-blind, placebo-controlled trial using an HIV-1 immunogen. The assay was validated following the United States Pharmacopeia guidelines. The analytical parameters assessed were sensitivity, specificity, linearity and precision. METHODS: The quantitative analysis was obtained by (1) co-amplifying HIV-1 DNA targets with an endogenous control (globin); (2) extrapolating the target values using HIV-1 and globin standard curves; and (3) normalizing the HIV-1 copy numbers to the globin copy numbers (genomic DNA load). RESULTS: With United States Pharmacopeia assay validation methodology, the HIV-1 DNA polymerase chain reaction assay proved to be sensitive, specific, linear and precise and the evaluation of the relative difference between two consecutive blood samples was reproducible. The intra-assay variability, which examines the reproducibility of replicates, was determined using a conservative assessment (tolerance intervals). We established that an increase of 60% or more in the number of DNA copies or a decrease of 38% or more was significantly greater than the variation due to random or experimental error and therefore attributed this variability to a significant change in the HIV-1 DNA copy number. CONCLUSION: We developed and validated a polymerase chain reaction method for the precise quantitation of HIV-1 DNA in peripheral blood mononuclear cells. This assay was able to detect changes in viral loads in HIV-1-infected asymptomatic subjects enrolled in a double-blind placebo-controlled trial using an HIV-1 immunogen.

Biomarkers↗

PubMed1990

Safety and tolerability of single intravenous doses of T cell modulatory peptide (TCMP-80) in healthy volunteers.

T Cell Modulatory Peptide (TCMP-80), L-lysine-L-serine, is a synthetic dipeptide structurally related to a selected amino acid sequence in human immunoglobulin G. Based on in vitro and preclinical in vivo testing, TCMP-80 has immunomodulatory properties. This report describes the first administration of TCMP-80 to man in a randomized, double-blind, placebo-controlled, single rising-dose tolerability trial. Healthy male volunteers received TCMP-80 or placebo as a 10-minute intravenous infusion. At weekly intervals, two of four subjects were given TCMP-80; the remaining two received placebo. Each subject could receive only one dose during the study. Dosing started at 0.01 mg/kg and was increased to 0.03, 0.1, 0.3, 1, 3, 6.5, and 10 mg/kg. CBCs, blood chemistries, urinalyses, and lymphocyte subset populations were monitored predose and postdose on Days 1, 5, and 14. Three placebo and three TCMP-80 subjects reported adverse events. Adverse events reported after TCMP-80 administration were mild in nature (headache, dizziness, hematoma at injection site), appeared to be independent of dose, and resolved without medical intervention. No clinically significant alterations in vital signs, physical examination parameters, or clinical laboratory values were observed. Based on the results of this study, TCMP-80 is safe and well-tolerated within the dose range studied when administered as single intravenous infusions. Additionally, this study design represents an approach to assess the safety of an investigational immunomodulatory drug.

Adult↗

PubMedDate not supplied

Characterization of highly purified, inactivated HIV-1 particles isolated by anion exchange chromatography.

This report characterizes inactivated, gp120 depleted, HIV-1 particles purified by an anion exchange chromatography production process. This antigen formulated with incomplete Freund's adjuvant constitutes Remune, which is being evaluated in a phase III clinical endpoint trial to determine the effect of this immune-based therapy on clinical progression of HIV-1 seropositive patients. Multiple production lots of the inactivated HIV-1 antigen strain HZ321, isolated by anion exchange chromatography, exhibit purity of > 95% by gel filtration. These findings are corroborated by thin section electron microscopy showing a homogenous field of intact particles. Analyses of the purified virus particles for protein, lipid, carbohydrate and RNA show structural retention of the envelope proteins, lipid bilayer and core components after large scale processing. The qualitative identification of at least 85% of total HIV-1 protein is determined by ELISA, Western blot, HPLC and amino acid sequencing analyses. Quantitative values are assigned to 50% of these proteins. The data confirm the presence of virally encoded proteins p6, p7, pI15, p17, p24, p32, pI39Gag, gp41, pp55Gag, p66/51, Vpr, Vif and Nef. Excellent consistency between production lots and equivalency to HIV-1 preparations purified by sucrose density gradient sedimentation has been established for protein and lipid composition, and overall purity. These findings further establish that non-viral encoded proteins and lipids are integral structural components of the intact virion and are not contaminants unique to a particular isolation method. The data confirm the presence of multicomponent antigens in the viral particles for stimulating a broad HIV-1 specific immune response. Finally, the work demonstrates that the two inactivation procedures (beta-propiolactone and gamma irradiation), which achieve efficient viral inactivation meeting US FDA guidelines, do not damage the protein antigens of the viral particles.

Carbohydrates↗