A Study Assessing Colonisation & Immunogenicity After Nasal Inoculation With N. Lactamica and Eradication on Day 4 or 14

NCT03549325 | Terminated Results

• 1 other identifier: MED1354
• Study Type: interventional
• Target: 21
• Locations: 1 country
• Sites: 1

Brief Summary

This study is part of a project that aims to develop a vaccine with N. lactamica that prevents meningitis. The investigators have previously given nose drops containing N. lactamica to over 340 volunteers, and shown that many of the volunteers (35-60%) become colonised without causing any illness or disease. In the future the investigators would like to modify N. lactamica so that it can carry vaccine molecules into the nose of children. To do this the investigators need to know more about the immune response generated against N. lactamica. Previously the investigators have shown that inoculation resulted in an immune (antibody) response in volunteers who were colonised. Taking an antibiotic called ciprofloxacin will treat N.lactamica in the nose and throat of the volunteers. The investigators need to know if the immune response to N. lactamica is the same when colonised volunteers are treated with the antibiotic after 4 days, is the same if the investigators treat volunteers after 14 days of carriage. This information will inform future studies.

Conditions

Meningitis, Meningococcal

Keywords

Neisseria lactamica; healthy volunteers; nasal inoculation; colonisation

Outcome Measures

Primary Outcomes (1)

• Measure the Antibodies, by Serological Antibody Titration, of Short Term Colonisation and Longer Colonisation

  Measure any rise in serological specific antibodies from samples taken at the start of the study (Day 0) and samples taken on Day 14 post inoculation and Day 28 post antibiotic eradication (Group 1 = Day 32 or Group 2 = Day 42)

  Up to 42 Days

Secondary Outcomes (2)

• Measure the Colonisation of Neisseria Lactamica

  Up to 14 Days

• Measure the Eradication of Neisseria Lactamica

  Up to 42 Days

Study Arms (2)

Group 1

EXPERIMENTAL

Nasal drops containing Neisseria lactamica are administered at Day 0 by the study doctor. Eradication therapy with the antibiotic Ciprofloxacin given on Day 4, unless required sooner. Follow up visits occur on Days 5, 14 and 32.

Biological: Neisseria lactamica

Group 2

EXPERIMENTAL

Nasal drops containing Neisseria lactamica are administered at Day 0 by the study doctor. Follow up visits on Day 4 and 7 to check for N. lactamica carriage. Eradication therapy with the antibiotic Ciprofloxacin given on Day 14, unless required sooner. Follow up visits occur on Days 15, 24 and 42.

Biological: Neisseria lactamica

Interventions

Neisseria lactamica BIOLOGICAL

Colonisation by bacteria is an immunising event; we proved this in humans by inoculating university students intranasally with the harmless commensal N. lactamica and we observed both specific systemic and mucosal antibody responses by 4 weeks. Experimental challenge with defined bacteria could tease out the Th17-mediated response mechanisms, which include waning of immunity over time, the induction of an incorrectly polarised T cell response, lack of cross-reactivity between strains or active immune evasion mechanisms employed by bacteria to subvert host immune effector mechanisms.

Group 1; Group 2

Eligibility Criteria

• Age: 18 Years - 45 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Healthy adults aged 18 to 45 years inclusive on the day of enrolment
• Fully conversant in the English language
• Able and willing (in the investigator's opinion) to comply with all study requirements
• Written informed consent to participate in the trial
• Willingness to take an antibiotic regimen after inoculation according to the study protocol
• For females only, willingness to practice continuous effective contraception (see below) during the study and a negative pregnancy test on the day(s) of screening and inoculation

You may not qualify if:

• Current active smokers
• N. lactamica or N. meningitidis detected on throat swab or nasal wash taken before the challenge
• Individuals who have a current infection at the time of inoculation
• Individuals who have been involved in other clinical trials involving receipt of an investigational product over the last 12 weeks or if there is planned use of an investigational product during the study period
• Individuals who have previously been involved in clinical trials investigating meningococcal vaccines or experimental challenge with N. lactamica
• Use of systemic antibiotics within the period 30 days prior to the challenge
• Any confirmed or suspected immunosuppressive or immune-deficient state, including HIV infection; asplenia; recurrent, severe infections and chronic (more than 14 days) immunosuppressant medication within the past 6 months (topical steroids are allowed)
• Use of immunoglobulins or blood products within 3 months prior to enrolment.
• History of allergic disease or reactions likely to be exacerbated by any component of the inoculum
• Contraindications to the use of ciprofloxacin, specifically a history of epilepsy, prolonged QT interval, hypersensitivity to quinolones or a history of tendon disorders related to quinolone use
• Any clinically significant abnormal finding on clinical examination
• Any other significant disease, disorder, or finding which may significantly increase the risk to the volunteer because of participation in the study, affect the ability of the volunteer to participate in the study or impair interpretation of the study data, for example recent surgery to the nasopharynx
• Occupational, household or intimate contact with immunosuppressed persons
• Pregnancy or lactation

Sponsors & Collaborators

• University Hospital Southampton NHS Foundation Trust: lead
• University of Southampton: collaborator

Study Sites (1)

Southampton NIHR Clinical Research Facility

Southampton, Hampshire, SO166YD, United Kingdom

Location

Related Publications (2)

• Evans CM, Pratt CB, Matheson M, Vaughan TE, Findlow J, Borrow R, Gorringe AR, Read RC. Nasopharyngeal colonization by Neisseria lactamica and induction of protective immunity against Neisseria meningitidis. Clin Infect Dis. 2011 Jan 1;52(1):70-7. doi: 10.1093/cid/ciq065.

  PMID: 21148522 RESULT

• Dale AP, Theodosiou AA, Gbesemete DF, Guy JM, Jones EF, Hill AR, Ibrahim MM, de Graaf H, Ahmed M, Faust SN, Gorringe AR, Polak ME, Laver JR, Read RC. Effect of colonisation with Neisseria lactamica on cross-reactive anti-meningococcal B-cell responses: a randomised, controlled, human infection trial. Lancet Microbe. 2022 Dec;3(12):e931-e943. doi: 10.1016/S2666-5247(22)00283-X.

  PMID: 36462524 DERIVED

MeSH Terms

Conditions

Meningitis, Meningococcal

Condition Hierarchy (Ancestors)

Meningitis, Bacterial; Central Nervous System Bacterial Infections; Bacterial Infections; Bacterial Infections and Mycoses; Infections; Meningococcal Infections; Neisseriaceae Infections; Gram-Negative Bacterial Infections; Central Nervous System Infections; Central Nervous System Diseases; Nervous System Diseases; Meningitis; Neuroinflammatory Diseases

Results Point of Contact

• Title: Dr. Diane Gbesemete
• Organization: University of Southampton

d.gbesemete@soton.ac.uk

02381204989

Study Officials

• Robert Read

  University of Southampton

  PRINCIPAL INVESTIGATOR

Publication Agreements

• PI is Sponsor Employee: No
• Restrictive Agreement: No

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: Group 1: Nasal inoculation with Neisseria lactamica with eradication on day 4 - up to 22 volunteers or until 11 colonised on day 4 Group 2: Nasal inoculation with Neisseria lactamica with eradication on day 14 - up to 22 volunteers or until 11 colonised on day 4

Study Record Dates

• First Submitted: October 23, 2017
• First Posted: June 8, 2018
• Study Start: March 13, 2017
• Primary Completion: December 2, 2021
• Study Completion: December 2, 2021
• Last Updated: February 12, 2026
• Results First Posted: February 12, 2026

Record last verified: 2026-01

Data Sharing

• IPD Sharing: Will not share

Locations

GB (1)