Publications by authors named "Pensiero M"

BACKGROUNDAn HIV-1 DNA vaccine composed of 7 highly conserved, structurally important elements (conserved elements, CE) of p24Gag was tested in a phase I randomized, double-blind clinical trial (HVTN 119, NCT03181789) in people without HIV. DNA vaccination of CE prime/CE+p55Gag boost was compared with p55Gag.METHODSTwo groups (n = 25) received 4 DNA vaccinations (CE/CE+p55Gag or p55Gag) by intramuscular injection/electroporation, including IL-12 DNA adjuvant.

View Article and Find Full Text PDF

Monoclonal antibodies are commonly engineered with an introduction of Met428Leu and Asn434Ser, known as the LS mutation, in the fragment crystallizable region to improve pharmacokinetic profiles. The LS mutation delays antibody clearance by enhancing binding affinity to the neonatal fragment crystallizable receptor found on endothelial cells. To characterize the LS mutation for monoclonal antibodies targeting HIV, we compared pharmacokinetic parameters between parental versus LS variants for five pairs of anti-HIV immunoglobin G1 monoclonal antibodies (VRC01/LS/VRC07-523LS, 3BNC117/LS, PGDM1400/LS PGT121/LS, 10-1074/LS), analyzing data from 16 clinical trials of 583 participants without HIV.

View Article and Find Full Text PDF

Background: An effective HIV vaccine will most likely need to have potent immunogenicity and broad cross-subtype coverage. The aim of the HIV Vaccine Trials Network (HVTN) 124 was to evaluate safety and immunogenicity of a unique polyvalent DNA-protein HIV vaccine with matching envelope (Env) immunogens.

Methods: HVTN 124 was a randomised, phase 1, placebo-controlled, double-blind study, including participants who were HIV seronegative and aged 18-50 years at low risk for infection.

View Article and Find Full Text PDF

Background: An approach to a preventive HIV vaccine is induction of effective broadly neutralizing antibodies (bnAbs) and effector binding antibodies (bAbs). Preclinical studies suggest that trimeric envelope (Env) proteins may elicit nAbs, which led to the development of the recombinant gp145 subtype C Env protein (gp145 C.6980) immunogen.

View Article and Find Full Text PDF

Background: HIV subtypes B and C together account for around 60% of HIV-1 cases worldwide. We evaluated the safety and immunogenicity of a subtype B DNA vaccine prime followed by a subtype C viral vector boost.

Methods: Fourteen healthy adults received DNA plasmid encoding HIV-1 subtype B nef/tat/vif and env (n = 11) or placebo (n = 3) intramuscularly (IM) via electroporation (EP) at 0, 1, and 3 months, followed by IM injection of recombinant vesicular stomatitis virus encoding subtype C Env or placebo at 6 and 9 months.

View Article and Find Full Text PDF

BACKGROUNDMosaic and consensus HIV-1 immunogens provide two distinct approaches to elicit greater breadth of coverage against globally circulating HIV-1 and have shown improved immunologic breadth in nonhuman primate models.METHODSThis double-blind randomized trial enrolled 105 healthy HIV-uninfected adults who received 3 doses of either a trivalent global mosaic, a group M consensus (CON-S), or a natural clade B (Nat-B) gp160 env DNA vaccine followed by 2 doses of a heterologous modified vaccinia Ankara-vectored HIV-1 vaccine or placebo. We performed prespecified blinded immunogenicity analyses at day 70 and day 238 after the first immunization.

View Article and Find Full Text PDF

BACKGROUNDHVTN 098, a randomized, double-blind, placebo-controlled trial, evaluated the safety, tolerability, and immunogenicity of PENNVAX-GP HIV DNA vaccine, administered with or without plasmid IL-12 (pIL-12), via intradermal (ID) or intramuscular (IM) electroporation (EP) in healthy, HIV-uninfected adults. The study tested whether PENNVAX-GP delivered via ID/EP at one-fifth the dose could elicit equivalent immune responses to delivery via IM/EP and whether inclusion of pIL-12 provided additional benefit.METHODSParticipants received DNA encoding HIV-1 env/gag/pol in 3 groups: 1.

View Article and Find Full Text PDF

Background: HVTN 100 evaluated the safety and immunogenicity of an HIV subtype C pox-protein vaccine regimen, investigating a 12-month booster to extend vaccine-induced immune responses.

Methods And Findings: A phase 1-2 randomized double-blind placebo-controlled trial enrolled 252 participants (210 vaccine/42 placebo; median age 23 years; 43% female) between 9 February 2015 and 26 May 2015. Vaccine recipients received ALVAC-HIV (vCP2438) alone at months 0 and 1 and with bivalent subtype C gp120/MF59 at months 3, 6, and 12.

View Article and Find Full Text PDF

In the RV144 trial, vaccine-induced V1V2 IgG correlated with decreased HIV-1 risk. We investigated circulating antibody specificities in two phase 1 poxvirus prime-protein boost clinical trials conducted in South Africa: HVTN 097 (subtype B/E) and HVTN 100 (subtype C). With cross-subtype peptide microarrays and multiplex binding assays, we probed the magnitude and breadth of circulating antibody responses to linear variable loop 2 (V2) and conformational V1V2 specificities.

View Article and Find Full Text PDF

Background: The durability and breadth of human immunodeficiency virus type 1 (HIV-1)-specific immune responses elicited through vaccination are important considerations in the development of an effective HIV-1 vaccine. Responses to HIV-1 envelope subunit protein (Env) immunization in humans are often described as short-lived.

Methods: We enrolled 16 healthy volunteers who had received priming with an HIV-1 subtype B Env vaccine given with MF59 adjuvant 5-17 years previously and 20 healthy unprimed volunteers.

View Article and Find Full Text PDF

Background: Modest efficacy was reported for the HIV vaccine tested in the RV144 trial, which comprised a canarypox vector (ALVAC) and envelope (env) glycoprotein (gp120). These vaccine components were adapted to express HIV-1 antigens from strains circulating in South Africa, and the adjuvant was changed to increase immunogenicity. Furthermore, 12-month immunisation was added to improve durability.

View Article and Find Full Text PDF

On May 21st, 2015, the U.S. National Institute of Allergy and Infectious Diseases (NIAID) convened a workshop on delivery devices for nucleic acid (NA) as vaccines in order to review the landscape of past and future technologies for administering NA (e.

View Article and Find Full Text PDF

Background: The safety and immunogenicity of SAAVI DNA-C2 (4 mg IM), SAAVI MVA-C (2.9 x 109 pfu IM) and Novartis V2-deleted subtype C gp140 (100 mcg) with MF59 adjuvant in various vaccination regimens was evaluated in HIV-uninfected adults in South Africa.

Methods: Participants at three South African sites were randomized (1:1:1:1) to one of four vaccine regimens: MVA prime, sequential gp140 protein boost (M/M/P/P); concurrent MVA/gp140 (MP/MP); DNA prime, sequential MVA boost (D/D/M/M); DNA prime, concurrent MVA/gp140 boost (D/D/MP/MP) or placebo.

View Article and Find Full Text PDF

A phase I safety and immunogenicity study investigated South African AIDS Vaccine Initiative (SAAVI) HIV-1 subtype C (HIV-1C) DNA vaccine encoding Gag-RT-Tat-Nef and gp150, boosted with modified vaccinia Ankara (MVA) expressing matched antigens. Following the finding of partial protective efficacy in the RV144 HIV vaccine efficacy trial, a protein boost with HIV-1 subtype C V2-deleted gp140 with MF59 was added to the regimen. A total of 48 participants (12 U.

View Article and Find Full Text PDF

Background.  We report the first-in-human safety and immunogenicity evaluation of a highly attenuated, replication-competent recombinant vesicular stomatitis virus (rVSV) human immunodeficiency virus (HIV)-1 vaccine. Methods.

View Article and Find Full Text PDF

Unlabelled: Eliciting broadly reactive functional antibodies remains a challenge in human immunodeficiency virus type 1 (HIV-1) vaccine development that is complicated by variations in envelope (Env) subtype and structure. The majority of new global HIV-1 infections are subtype C, and novel antigenic properties have been described for subtype C Env proteins. Thus, an HIV-1 subtype C Env protein (CO6980v0c22) from an infected person in the acute phase (Fiebig stage I/II) was developed as a research reagent and candidate immunogen.

View Article and Find Full Text PDF

The Division of AIDS Vaccine Research Program funds the discovery and development of HIV/AIDS vaccine candidates. Basic researchers, having discovered a potential vaccine in the laboratory, next want to take that candidate into the clinic to test the concept in humans, to see if it translates. Many of them have heard of "cGMP" and know that they are supposed to make a "GMP product" to take into the clinic, but often they are not very familiar with what "cGMP" means and why these good practices are so important.

View Article and Find Full Text PDF

Background: Clade B DNA and recombinant modified vaccinia Ankara (MVA) vaccines producing virus-like particles displaying trimeric membrane-bound envelope glycoprotein (Env) were tested in a phase 2a trial in human immunodeficiency virus (HIV)-uninfected adults for safety, immunogenicity, and 6-month durability of immune responses.

Methods: A total of 299 individuals received 2 doses of JS7 DNA vaccine and 2 doses of MVA/HIV62B at 0, 2, 4, and 6 months, respectively (the DDMM regimen); 3 doses of MVA/HIV62B at 0, 2, and 6 months (the MMM regimen); or placebo injections.

Results: At peak response, 93.

View Article and Find Full Text PDF

Recent advances in the development of humanized mice hold great promise to advance our understanding of protective immunity to human immunodeficiency virus (HIV) infection and to aid in the design of an effective HIV vaccine. This supplement of the Journal of Infectious Diseases summarizes work in the humanized mouse model presented at an HIV Humanized Mouse workshop in Boston, Massachusetts, in November 2012, including recent advances in the development of humanized mice, the trafficking of human immune cells following mucosal HIV transmission, the role of immune activation and Toll-like receptor agonists in the control of HIV, the induction and efficacy of HIV-specific cellular and humoral immune responses, and the preclinical modeling of novel anti-HIV therapeutics. Many gaps remain in our understanding of how to design an effective HIV vaccine and novel therapeutics to eliminate the viral reservoir.

View Article and Find Full Text PDF

Background: DNA vaccines have been very poorly immunogenic in humans but have been an effective priming modality in prime-boost regimens. Methods to increase the immunogenicity of DNA vaccines are needed.

Methods: HIV Vaccine Trials Network (HVTN) studies 070 and 080 were multicenter, randomized, clinical trials.

View Article and Find Full Text PDF

On the basis of positive preclinical data, we evaluated the safety and immunogenicity of an alphavirus replicon HIV-1 subtype C gag vaccine (AVX101), expressing a nonmyristoylated form of Gag, in two double-blind, randomized, placebo-controlled clinical trials in healthy HIV-1-uninfected adults. Escalating doses of AVX101 or placebo were administered subcutaneously to participants in the United States and Southern Africa. Because of vaccine stability issues, the first trial was halted prior to completion of all dose levels and a second trial was implemented.

View Article and Find Full Text PDF

We evaluated replication-defective poxvirus vectors (modified vaccinia Ankara [MVA] and fowlpox [FPV]) in a homologous and heterologous vector prime-boost vaccination regimen containing matching HIV inserts (MVA-HIV and FPV-HIV) given at months 0, 1, 3, 5 and 7 in 150 healthy HIV-negative vaccinia-naïve participants. FPV-HIV alone was poorly immunogenic, while the high dose (10(9)pfu/2 ml) of MVA-HIV alone elicited maximal responses after two injections: CD4+ and CD8+ T-cell responses in 26/55 (47.3%) and 5/60 (8.

View Article and Find Full Text PDF

Recent advances in science, which have aided HIV-1 vaccine development, include an improved understanding of HIV-1 envelope structure and function, expansion of the pipeline with innovative vaccine strategies, promising multi-gene and multi-clade vaccines that elicit cellular immunity, conduct of clinical trials in a global network, and development of validated techniques that enable simultaneous measurement of multiple T cell vaccine-induced immune responses in humans. A common feature of several preventive vaccine strategies now in early clinical trials is their ability in nonhuman primates to attenuate clinical disease rather than completely prevent HIV-1 infection. One vaccine concept has been tested in large-scale clinical trials, two are currently in efficacy trials, and one more is poised to enter efficacy trial in the next few years.

View Article and Find Full Text PDF

Manufacturing of retroviral vectors for gene therapy is complicated by the sensitivity of these viruses to stress forces during purification and concentration. To isolate viruses that are resistant to these manufacturing processes, we performed breeding of six ecotropic murine leukemia virus (MLV) strains by DNA shuffling. The envelope regions were shuffled to generate a recombinant library of 5 x 106 replication-competent retroviruses.

View Article and Find Full Text PDF