Immunogenicity of an Intradermal Qdenga Vaccine Among Healthy Volunteers

Immunogenicity of an Intradermal Qdenga Vaccine Among Healthy Volunteers: A Pilot Study

Official title: Immunogenicity of an intradermal Qdenga vaccine among healthy volunteers: A pilot study

Study Overview

• Status: Completed
• Conditions: Dengue
• Intervention / Treatment: Biological: Vaccine

Detailed Description

As in the setting of low- to middle-income countries, to demonstrating that lower doses of vaccine via intradermal route can still elicit robust immune responses, thereby lowering the overall cost of vaccination might be particularly meaningful ,with possible extra benefit of experiencing fewer side effects or risk of allergy. This study goal is to explores the potential of intradermal administration of Qdenga, hypothesizing that a lower dose via this route could achieve adequate immunogenicity compared to the standard subcutaneous administration, thus offering a cost-effective alternative particularly in low-resource settings where dengue is most prevalent.

• Study Type: Interventional
• Enrollment (Actual): 29
• Phase: Early Phase 1

Contacts and Locations

Study Locations

• Thailand
  • Changwat Songkhla
    • Hat Yai, Changwat Songkhla, Thailand, 90110
      • Faculty of Medicine, Prince of Songkla University
    • Hat Yai, Changwat Songkhla, Thailand, 90110
      • Prince of Songkla University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Thai adult aged 18-60 years, who not previously received dengue vaccine.
• The subjects are able to and willing to comply with the requirements of the clinical trial program and could complete the 3-month follow-up of the study.
• Individuals who are in good health condition at the time of entry into the trial as determined by medical history, physical examination and clinical judgment of the investigator and meet the requirements of immunization
• The subject can provide with informed consent and sign informed consent form

Exclusion Criteria:

• Have a medical history or family history of convulsion, epilepsy, encephalopathy and psychosis.
• Be allergic to any component of the research vaccines or used to have a history of hypersensitivity or serious reactions to vaccination.
• Women with positive urine pregnancy test, pregnant or breast-feeding, or have a pregnancy plan within six months.
• Have acute infectious diseases, including dengue infection
• Have severe chronic diseases or condition in progress cannot be controlled. For example, poor controlled DM and uncontrolled HT.
• Have the history of urticaria 1 year before receiving the investigational vaccine.
• Have known underlying diseases of thrombocytopenia or other coagulation disorders (which may cause contraindications for intramuscular injection).
• Have needle sickness.
• Have the history of immunosuppressive therapy, cytotoxic therapy or systemic corticosteroids
• Have received blood products within 4 months before injection of investigational vaccines.
• Under anti-tuberculosis treatment.
• Not be able to follow the protocol, or not be able to understand the informed consent according to the researcher's judgment, due to various medical, psychological, social or other conditions.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: SC ID; subcutaneous Qdenga for 1st vaccination then intradermal Qdenga for 2nd vaccination	Biological: Vaccine; Subcutaneous route vs Intradermal route
Active Comparator: SC SC; subcutaneous Qdenga for 1st vaccination then subcutaneous Qdenga for 2nd vaccination	Biological: Vaccine; Subcutaneous route vs Intradermal route

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Dengue IgG Level	To measure Antibody level for dengue by ELISA on day 0, day 30 and day 120 after 1st vaccination	Day 0 (Baseline), Day 30 (30 days post 1st vaccination) and Day 120 (30 days post 2nd vaccination)
CD4 T Cell Responses	To measure T cell responses to dengue antigen by ELISpot on day 0, day 30 and day 120 after 1st vaccination.	Day 0 (Baseline), Day 30 (30 days post 1st vaccination) and Day 120 (30 days post 2nd vaccination)
CD8 T Cell Response	To measure T cell responses to dengue antigen by ELISpot on day 0, day 30 and day 120 after 1st vaccination.	Day 0 (Baseline), Day 30 (30 days post 1st vaccination) and Day 120 (30 days post 2nd vaccination)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
All-Cause Mortality	Death from any cause occurring from the first vaccination until the end of the 120-day follow-up period.	at day 7 and 30 post each vaccination
Serious Adverse Events	Any untoward medical occurrence during the study period that results in death, is life-threatening, requires inpatient hospitalization or prolongation of existing hospitalization, results in persistent or significant disability or incapacity, or is a congenital anomaly/birth defect, regardless of its relationship to the study vaccine.	at day 7 and 30 post each vaccination
Local Reactions	- Include any reported pain, swelling, erythema or nodule at the vaccination site	at day 7 and 30 post each vaccination
Systemic Reactions	fever, chill, fatique, headache, myalgia	at day 7 and 30 post each vaccination
Pain at Vaccination Site, 7 Day Post 1st Vaccination	Injection-site pain reported during the 7-day period following the first vaccine dose.	7 day post 1st vaccination
Erythema at Vaccination Site, 7 Day Post 1st Vaccination	Erythema at vaccination site reported during the 7-day period following the first vaccine dose.	7 day post 1st vaccination
Malaise, 7 Day Post 1st Vaccination	Self-reported malaise during the 7-day period following the first vaccine dose.	7 day post 1st vaccination
Headache, 7 Day Post 1st Vaccination	Self-reported headache during the 7-day period following the first vaccine dose.	7 day post 1st vaccination
Erythema at Vaccination Site, 7 Day Post 2nd Vaccination	Erythema at vaccination site reported during the 7-day period following the second vaccine dose.	7 day post 2nd vaccination

Collaborators and Investigators

• Sponsor: Prince of Songkla University

Study record dates

Study Major Dates

• Study Start (Actual): April 19, 2025
• Primary Completion (Actual): August 30, 2025
• Study Completion (Actual): September 30, 2025

Study Registration Dates

• First Submitted: February 14, 2025
• First Submitted That Met QC Criteria: February 14, 2025
• First Posted (Actual): February 20, 2025

Study Record Updates

• Last Update Posted (Estimated): January 16, 2026
• Last Update Submitted That Met QC Criteria: December 27, 2025
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Keywords: Safety; Immunogenicity; intradermal Qdenga
• Additional Relevant MeSH Terms: Vector Borne Diseases; Mosquito-Borne Diseases; Infections; RNA Virus Infections; Virus Diseases; Arbovirus Infections; Flavivirus Infections; Flaviviridae Infections; Hemorrhagic Fevers, Viral; Dengue; Biological Products; Complex Mixtures; Vaccines
• Other Study ID Numbers: REC.67-475-14-1

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: The data will be anonymized.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No