Biomedical subjects

Albert T Profy

Publications and source records attributed to Albert T Profy.

9 recordsLinked to original sources

PubMed2006

ACIDFORM inactivates herpes simplex virus and prevents genital herpes in a mouse model: optimal candidate for microbicide combinations.

The acidic vaginal milieu is presumed to inactivate pathogens but is neutralized by semen. This notion fostered the development of acid-buffering products, such as ACIDFORM (developed by Program for Topical Prevention of Conception and Disease, Rush University, and licensed by Instead), as microbicides. However, the extent and mechanism of protective activity provided by buffering gels is not known. Exposure of herpes simplex virus (HSV) to pH 4.5 or lower irreversibly inactivated HSV and reduced HSV yields by at least 90%; exposure to pH 5.0 had little or no effect. Pretreatment of HSV-2 with pH 3.5-4.5 triggered proteolysis, disrupting the HSV particle and resulting in a reduction in binding and invasion. ACIDFORM protected 21 (81%) of 26 mice from genital herpes, compared with 3 (12%) of 25 mice who received a placebo gel. ACIDFORM retained significant activity if mice were challenged with HSV delivered in seminal fluid. These findings suggest that ACIDFORM offers considerable protection against HSV and may be an optimal candidate for developing combination microbicides.

Animals↗

PubMed2006

Direct measurement of in-vivo vaginal microbicide levels of PRO 2000 achieved in a human safety study.

OBJECTIVES: To directly measure the cervico-vaginal lavage (CVL) and plasma PRO 2000 concentrations achieved by vaginal dosing. DESIGN: A sub-study of a prospective randomized, double-blind phase 1 trial of a candidate vaginal microbicide, PRO 2000 gel. METHODS: Thirty-six sexually abstinent women self-administered 4% PRO 2000 gel, 0.5% PRO 2000 gel or placebo gel twice on day 0 and then once daily for a further 12 days. RESULTS: There was no evidence of systemic absorption of PRO 2000. PRO 2000 concentrations in CVL exceeded 25 microg/ml in all women in both the 4 and 0.5% groups at 2 h post-first dose, and in 10 of 12 of the women in the 4% gel group compared with five of 12 of women in the 0.5% group at 12 h post-seventh dose. Single use of both 4 and 0.5% PRO 2000 gels was therefore associated with levels of PRO 2000 in CVL that would be capable of preventing HIV infection in vitro, although the 4% gel gave a greater margin of excess. Levels substantially in excess of the target concentration were present 12 h after repeated dosing in twice as many 4% gel recipients compared with 0.5% gel recipients. CONCLUSIONS: Both PRO 2000 gel strengths provided satisfactory in-vivo HIV inhibitory concentrations. However, our observations show that higher concentrations of PRO 2000 are likely to provide a greater margin of potential efficacy in the context of sexual intercourse provided safety issues are equivalent for differing concentrations of the agent.

Absorption↗

PubMed2005

PRO 2000 gel inhibits HIV and herpes simplex virus infection following vaginal application: a double-blind placebo-controlled trial.

BACKGROUND: Microbicides used to prevent the transmission of human immunodeficiency virus (HIV) are advancing to clinical trials on the basis of activity observed in vitro and in animal models. However, no data demonstrate activity of microbicides after application in humans. This study was designed to determine the antiviral activity in cervicovaginal lavage (CVL) samples collected after intravaginal application of 0.5% PRO 2000 gel (Indevus). METHODS: A randomized, double-blind study was conducted to assess the anti-HIV and anti-herpes simplex virus (HSV) activity of PRO 2000 in CVL samples obtained at screening (48 hours before) and 1 hour after application of study or placebo gel. HeLa cells or human macrophages were inoculated with CVL samples spiked with replication-defective HIV containing a luciferase indicator gene and pseudotyped with an R5 envelope. Human cervical epithelial cells were inoculated with CVL samples and challenged with HSV-2(G), and the virus titer was then determined. RESULTS: CVL samples obtained after application of PRO 2000 gel significantly inhibited HIV and HSV infection by at least 1000-fold, compared with CVL samples obtained at screening (P < .001). There were no differences in cytokine levels between the drug and placebo groups. CONCLUSIONS: PRO 2000 gel (0.5%) is sufficiently bioavailable and retains substantial antiviral activity after intravaginal application. This strategy provides a mechanism for testing the efficacy of a microbicide before embarking on large-scale clinical trials.

Administration, Intravaginal↗

PubMed2005

Candidate sulfonated and sulfated topical microbicides: comparison of anti-human immunodeficiency virus activities and mechanisms of action.

Poly(styrene 4-sulfonate), cellulose sulfate, polymethylenehydroquinone, and PRO 2000 are sulfated or sulfonated polymers (SPs) under development as topical microbicides. They are presumed to work through similar mechanisms of action, although to date there has been no extensive comparison of their anti-human immunodeficiency virus activities. To determine whether any of these candidate microbicides offers a potential advantage, their in vitro activities, mechanisms of action, stabilities in biological secretions, and toxicities were compared. All four compounds were found to be active against X4, R5, and dualtropic primary isolates and against X4 and R5 laboratory-adapted strains in CD4+ T cells, macrophages, and single-coreceptor cell lines. Our single-cycle experiments using pseudotyped virus suggest that all four SPs function at the binding and entry stages of the viral life cycle but differ in degree of postentry effect. Surface plasmon resonance analyses demonstrate that SPs bind to X4 and R5 monomeric glycoprotein 120 with similar high binding affinities. When mixed with cervicovaginal lavage fluid, SPs maintain inhibitory activity at concentrations achievable in formulations.

Administration, Topical↗

PubMed2004

Candidate topical microbicides bind herpes simplex virus glycoprotein B and prevent viral entry and cell-to-cell spread.

Topical microbicides designed to prevent acquisition of sexually transmitted infections are urgently needed. Nonoxynol-9, the only commercially available spermicide, damages epithelium and may enhance human immunodeficiency virus transmission. The observation that herpes simplex virus (HSV) and human immunodeficiency virus bind heparan sulfate provided the rationale for the development of sulfated or sulfonated polymers as topical agents. Although several of the polymers have advanced to clinical trials, the spectrum and mechanism of anti-HSV activity and the effects on soluble mediators of inflammation have not been evaluated. The present studies address these gaps. The results indicate that PRO 2000, polystyrene sulfonate, cellulose sulfate, and polymethylenehydroquinone sulfonate inhibit HSV infection 10,000-fold and are active against clinical isolates, including an acyclovir-resistant variant. The compounds formed stable complexes with glycoprotein B and inhibit viral binding, entry, and cell-to-cell spread. The effects may be long lasting due to the high affinity and stability of the sulfated compound-virus complex, as evidenced by surface plasmon resonance studies. The candidate microbicides retained their antiviral activities in the presence of cervical secretions and over a broad pH range. There was little reduction in cell viability following repeated exposure of human endocervical cells to these compounds, although a reduction in secretory leukocyte protease inhibitor levels was observed. These studies support further development and rigorous evaluation of these candidate microbicides.

Anti-Infective Agents, Local↗

PubMed2003

Recurring conformation of the human immunodeficiency virus type 1 gp120 V3 loop.

The crystal structure of the human immunodeficiency virus type 1 (HIV-1) neutralizing, murine Fab 83.1 in complex with an HIV-1 gp120 V3 peptide has been determined to 2.57 A resolution. The conformation of the V3 loop peptide in complex with Fab 83.1 is very similar to V3 conformations seen previously with two other neutralizing Fabs, 50.1 and 59.1. The repeated identification of this same V3 conformation in complex with three very different, neutralizing antibodies indicates that it is a highly preferred structure for V3 loops on some strains of the HIV-1 virus.

Amino Acid Sequence↗

PubMed2003

Safety and acceptability of penile application of 2 candidate topical microbicides: BufferGel and PRO 2000 Gel: 3 randomized trials in healthy low-risk men and HIV-positive men.

OBJECTIVES: To assess safety and acceptability of penile application of BufferGel (ReProtect, Baltimore, MD) and PRO 2000 Gel (Indevus Pharmaceuticals, Lexington, MA)compared with placebo among low-risk sexually abstinent men and HIV-positive sexually abstinent men. DESIGN: Seventy-two healthy low-risk men (36 uncircumcised) and 25 HIV-positive men (12 uncircumcised) were enrolled in 3 double-blind, single-center studies as follows: 36 low-risk men in a study of BufferGel and K-Y Jelly (McNeil-PPC, Skillman, NJ) placebo; 36 low-risk men in a study of PRO 2000 Gel and vehicle placebo; and 25 HIV-positive men in a crossover study of BufferGel, PRO 2000 Gel, and K-Y Jelly placebo. METHODS: Participants applied product to the penis on 7 consecutive nights, kept study diaries, and were then interviewed and examined. Urine was tested for inflammation by leukocyte esterase. RESULTS: No serious adverse events (AEs) or urethral inflammation was detected. During use of BufferGel, 3 low-risk men (13%) reported 6 AEs and 2 HIV-positive men (8%) reported 3 AEs. During use of PRO 2000 Gel, 4 low-risk men (17%) reported 6 AEs and 1 HIV-positive participant (4%) had 1 AE. AE rates during use of BufferGel and PRO 2000 Gel use were not significantly different from rates observed during placebo. One low-risk man (4%) would object to his partners using BufferGel and 3 (13%) to PRO 2000 Gel. Two HIV-positive men (8%) reported they would object to partners using either BufferGel or PRO 2000 Gel. CONCLUSIONS: Daily application of BufferGel and PRO 2000 Gel directly to the penis consecutively for 7 days was generally safe and well tolerated among healthy low-risk men and HIV-positive men. These microbicides have acceptable safety profiles to proceed with planned phase 3 vaginal microbicide trials.

Acrylic Resins↗

PubMed2003

Safety and tolerability of vaginal PRO 2000 gel in sexually active HIV-uninfected and abstinent HIV-infected women.

OBJECTIVES: To evaluate once or twice daily vaginal exposure to 2 and 4% PRO 2000 Gel, a naphthalene sulfonate polymer microbicide, in sexually active HIV-uninfected women to determine the highest tolerated frequency and concentration combination, and to assess this in sexually abstinent HIV-infected women. METHODS: Sixty three women from Providence, Philadelphia, Durban and Johannesburg were enrolled after being screened to exclude pre-existing illnesses and were instructed to use the product once or twice daily for 14 intermenstrual days. They underwent colposcopy prior to product use and after 14 days of product use, with a pelvic examination at day 7. RESULTS: The product was well tolerated, with no serious adverse events, even though 73% of the participants had at least one adverse experience: 82% of these were classified as mild, and over 90% of the findings and symptoms were localized to the genital tract. Women who used the 4% gel twice daily tended to have more adverse events than all the other groups. Three participants did not complete the study; one because of Herpes simplex virus cervicitis, the second because of epithelial disruption, and the third because she became pregnant. The remaining participants adhered to the study protocol and indicated that they would use the product if it were shown to be effective. CONCLUSIONS: PRO 2000 Gel was safe and well tolerated in sexually active HIV-uninfected and sexually abstinent HIV-infected women, enabling the product to be considered for evaluation in efficacy trials.

Administration, Intravaginal↗

PubMed2003

The acceptability of an investigational vaginal microbicide, PRO 2000 Gel, among women in a phase I clinical trial.

PURPOSE: Vaginal microbicides will provide a woman-initiated prevention strategy that could substantially reduce rates of HIV infection. The acceptability of microbicides will greatly influence the use and, hence, effectiveness of such products. In this study, the acceptability of an investigational microbicide, PRO 2000 Gel (Indevus Pharmaceuticals, Inc., Lexington, MA), was assessed, and women's opinions about microbicides and their potential for real world use were gathered. METHODS: Quantitative and qualitative data were collected from 30 U.S. and 33 South African women. All sexually active HIV-uninfected women and all sexually abstinent HIV-infected women participating in this phase I clinical trial stated in a survey that they would use PRO 2000 Gel if they had reason to be concerned about HIV and the product were available. Qualitative data, however, provided insight into the nuances of acceptability ratings. Women rated product safety, ease of use, and positive effects on sexual pleasure among the most important characteristics of acceptable microbicides. RESULTS: Opinions regarding product leakage, contraceptive capability, and the ability to be used without partners noticing, as well as characteristics of the product itself, varied substantially based on the context of sex and perceptions of risk within each individual woman's life. CONCLUSIONS: As microbicide development continues and the first investigational products move into efficacy trials, the needs and preferences of those women who constitute the potential users of microbicides become paramount. Providing woman-initiated microbicides that are safe, easy to use, and pleasurable will be key to the impact these products will have on the AIDS epidemic worldwide.

Administration, Intravaginal↗