title: Evaluation of safety and efficacy as an adjuvant for the chitosan-based vaccine delivery vehicle ViscoGel in a single-blind randomised Phase I/IIa clinical trial.
abstract: ViscoGel, a chitosan-based hydrogel, has earlier been shown to improve humoral and cell-mediated immune responses in mice. In this study, a Phase I/IIa clinical trial was conducted to primarily evaluate safety and secondarily to study the effects of ViscoGel in combination with a model vaccine, Act-HIB to Haemophilus influenzae type b, administered as a single intramuscular injection. Healthy volunteers of both sexes, ages 22-50 and not previously vaccinated to HIB, were recruited. The trial had two phases. In Phase A, three ascending dose levels of ViscoGel (25, 50 and 75mg) were evaluated for safety in 3×10 subjects. Phase B had a single-blind, randomised, parallel-group design evaluating safety and efficacy in five groups, 20 subjects/group, comparing vaccination with 0.2μg or 2μg Act-HIB alone or combined with ViscoGel (50mg) and one group receiving the standard Act-HIB dose (10μg). No safety or tolerability concerns were identified. Local, transient reactions at the injection site were the most common adverse events. These were more frequent in groups receiving Act-HIB+ViscoGel, while other AEs were recorded at similar frequency in Act-HIB and Act-HIB+ViscoGel groups. Efficacy was evaluated by measuring serum anti-HIB antibodies and cellular responses in peripheral blood mononuclear cells (PBMC). There was a large variation in baseline anti-HIB antibody titres and no adjuvant effect was observed on the anti-HIB antibody production in groups vaccinated with Act-HIB+ViscoGel. ELISpot analyses revealed increased interferon-γ (IFN-γ) responses to Act-HIB in PBMCs from subjects vaccinated with Act-HIB in combination with ViscoGel, compared to groups receiving Act-HIB alone. Moreover, ViscoGel counteracted an inhibitory effect of Act-HIB vaccination on the IFN-γ response to both the vaccine itself and an irrelevant influenza antigen. In summary, ViscoGel was found to be safe and well-tolerated, supporting further examination of ViscoGel as a new innovative vehicle for vaccine development.
authors.affiliation: Viscogel AB, Solna, Sweden; Karolinska Institutet, Department of Clinical Neuroscience, Therapeutic Immune Design Unit, Stockholm, Sweden.
authors.forename: Theresa
authors.initials: T
authors.lastname: Neimert-Andersson
authors.affiliation: Viscogel AB, Solna, Sweden; Karolinska Institutet, Department of Clinical Neuroscience, Therapeutic Immune Design Unit, Stockholm, Sweden.
authors.forename: Jonas
authors.initials: J
authors.lastname: Binnmyr
authors.affiliation: Viscogel AB, Solna, Sweden.
authors.forename: Mattias
authors.initials: M
authors.lastname: Enoksson
authors.affiliation: Viscogel AB, Solna, Sweden.
authors.forename: Joakim
authors.initials: J
authors.lastname: Langebäck
authors.affiliation: Viscogel AB, Solna, Sweden.
authors.forename: Louise
authors.initials: L
authors.lastname: Zettergren
authors.affiliation: Viscogel AB, Solna, Sweden.
authors.forename: Anne-Charlotte
authors.initials: AC
authors.lastname: Hällgren
authors.affiliation: Viscogel AB, Solna, Sweden.
authors.forename: Henry
authors.initials: H
authors.lastname: Franzén
authors.affiliation: Viscogel AB, Solna, Sweden; Karolinska Institutet, Department of Clinical Neuroscience, Therapeutic Immune Design Unit, Stockholm, Sweden.
authors.forename: Sara
authors.initials: S
authors.lastname: Lind Enoksson
authors.affiliation: Karolinska Institutet, Department of Medicine, Clinical Pharmacology Unit, Stockholm, Sweden.
authors.forename: Pierre
authors.initials: P
authors.lastname: Lafolie
authors.affiliation: Karolinska Institutet, Department of Clinical Neuroscience, Therapeutic Immune Design Unit, Stockholm, Sweden.
authors.forename: Alf
authors.initials: A
authors.lastname: Lindberg
authors.affiliation: Karolinska Trial Alliance (KTA) Phase-I Unit, Karolinska University Hospital, Huddinge, Sweden.
authors.forename: Nabil
authors.initials: N
authors.lastname: Al-Tawil
authors.affiliation: Viscogel AB, Solna, Sweden.
authors.forename: Mats
authors.initials: M
authors.lastname: Andersson
authors.affiliation: Viscogel AB, Solna, Sweden.
authors.forename: Peter
authors.initials: P
authors.lastname: Singer
authors.affiliation: Karolinska Institutet, Department of Clinical Neuroscience, Therapeutic Immune Design Unit, Stockholm, Sweden.
authors.forename: Hans
authors.initials: H
authors.lastname: Grönlund
authors.affiliation: Viscogel AB, Solna, Sweden; Karolinska Institutet, Department of Clinical Neuroscience, Therapeutic Immune Design Unit, Stockholm, Sweden. Electronic address: Guro.Gafvelin@ki.se.
authors.forename: Guro
authors.initials: G
authors.lastname: Gafvelin
mesh_terms: D000276:Adjuvants, Immunologic / Q000009:adverse effects / Q000494:pharmacology*; D000328:Adult; D000907:Antibodies, Bacterial / Q000097:blood; D048271:Chitosan / Q000737:chemistry*; D005260:Female; D006192:Haemophilus Infections / Q000517:prevention & control; D018073:Haemophilus Vaccines / Q000627:therapeutic use*; D006801:Humans; D020100:Hydrogels / Q000009:adverse effects / Q000494:pharmacology*; D007111:Immunity, Cellular; D007371:Interferon-gamma / Q000276:immunology; D008297:Male; D008875:Middle Aged; D016037:Single-Blind Method; D018074:Vaccines, Conjugate / Q000627:therapeutic use; D055815:Young Adult
chemical_list: C570267:Act-Hib vaccine; D000276:Adjuvants, Immunologic; D000907:Antibodies, Bacterial; D018073:Haemophilus Vaccines; D020100:Hydrogels; C573415:IFNG protein, human; D018074:Vaccines, Conjugate; D007371:Interferon-gamma; D048271:Chitosan
keywords: Adjuvant; Chitosan; Clinical trial; Haemophilus influenzae type B; Vaccine