A Phase 2 interventional study of Etvax and Etvax in Healty Volunteers and Preventable Disease, Vaccine, sponsored by Scandinavian Biopharma AB. Completed at 1 site in Sweden. Open to participants aged 18 Years to 50 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-08-19.
Sponsored by Scandinavian Biopharma AB · Phase 2, Interventional, and Prevention
This is a phase 2,prospective double-blind, randomized, parallel-group study with the aim to demonstrate non-inferiority, in terms of immunogenicity, between the wet formulation and a newly developed partially dried formulation of selected components of ETVAX.
This is a phase 2, prospective double-blind, randomized, parallel-group study with the aim to demonstrate non-inferiority, in terms of immunogenicity, between the wet formulation and a newly developed partially dried formulation of selected components of ETVAX. A total number of 126 subjects is planned to be included in each arm of the study, i.e. 252 subjects in total. Assuming a 10% dropout rate the target number of subjects to be recruited per study arm is therefore 140, i.e. 280 subjects in total. Healthy volunteers between 18-50 years will be eligible for enrolment into the study.
Eligible subjects will be randomized on Day 1 (Visit 2) to receive either of the two oral formulations of ETVAX (1:1) and consecutively included the study. The treatment allocation (Wet formulation/Partially dried formulation) will be double-blind. The study subjects will receive two oral doses, two weeks apart (Day 1/Visit 2 and Day 15 /Visit 3).The dosing will occur at the clinic (CTC in Gothenburg, Sweden). A follow-up visit will be performed 7 days after the last (second) dose in all study subjects
The primary endpoint to be measured for each patient in the study is response (yes/no) to a vaccine. A vaccine responder will be defined by a ≥2-fold increase in IgA and/or IgG antibody levels against LTB in serum between post- compared to pre-immunization samples. The response rates (seroconversion rates) of IgA and/or IgG anti-LTB antibodies in serum will be derived and compared between the two treatment groups.
The secondary endpoint to be measured for each patient in the study is the occurrence of solicited symptoms for six days after each vaccination (day of vaccination and five subsequent days).
Exploratory analyses will be done to evaluate if ETVAX vaccination induces circulating antigen specific memory B- and/or T cells that can be assessed using recently established laboratory assays.
For the exploratory analyses, subgroups of subjects (n=20-40, evenly distributed between the two treatment arms) will participate in additional follow-up visits 5± 1, 30± 7 and 90± 14 days after the second dose. Blood samples will be collected on all exploratory visits. The extra visits and analyses for exploratory analyses may continue after the main part of the study has been completed and the database locked.
51 studies on the registry are indexed under Vaccine-Preventable Diseases; 13 are open to participants now.
This study's enrollment of 280 is above the median of 165 across 38 interventional studies indexed under Vaccine-Preventable Diseases.
Browse Vaccine-Preventable Diseases studies →Scandinavian Biopharma AB is the lead sponsor of 3 studies on the registry; none are open to participants now.
Counted across the registry records on this site, refreshed daily.
Exclusion criteria
The wet formulation consists of a liquid suspension of inactivated bacteria (ETEX 21-24) and LCTBA in one vial, freeze-dried dmLT adjuvant in a second vial, and effervescent buffer granules in a separate sachet. Prior to administration, the buffer is dissolved in 150 ml tap water, followed by the addition of the content of the vaccine vial (inactivated bacteria mixed with LCTBA) and reconstituted and diluted adjuvant dmLT from the second vial.
Biological: Etvax
The partially dried formulation, dmLT and LCTBA are spray-dried and mixed with the buffer granules and stabilizing excipients in a sachet. Prior to administration, the content of the buffer sachet (buffer, dmLT, and LCTBA) is dissolved in 150 ml tap water, followed by the addition of a liquid suspension of inactivated bacteria (ETEX 21-24).
Biological: Etvax
Preparation of complete Wet formulation. The vaccine supplied as a liquid, is mixed with the 150 ml of sodium bicarbonate buffer solution on the day of preparation for use on dosing day. Just prior to administration 10 µg of dmLT is added by pipette (50 µl).
Preparation of partially dry formulation. The partially dry formulation of vaccine is prepared by adding the effervescent powder containing the dmLT and LCTBA to 150 ml of water. After mixing, the content of the vaccine vial is added to the mixture and the vaccine is administered to the volunteer within 30 minutes after adding the buffer powder to the water.
Vaccine Response
The primary endpoint to be measured for each patient in the study is response (yes/no) to a vaccine. A vaccine responder will be defined by a ≥2-fold increase in IgA and/or IgG antibody levels against LTB in serum between post- compared to pre-immunization samples. The response rates (seroconversion rates) of IgA and/or IgG anti-LTB antibodies in serum will be derived and compared between the two treatment groups.
Time frame: 3 weeks
Solicited Symptoms After Vaccination
Occurrence of solicited symptoms for six days after each vaccination (day of vaccination and five subsequent days).
Time frame: 3 weeks
Levels of IgA and IgG Antibodies Mononuclear Cells (PBMCs)
Evaluation if ETVAX® vaccination induces circulating antigen specific memory B- and/or T cells.
Time frame: 3 months
| Milestone | The Wet Formulation of ETVAX. | The Partially Dried Formulation of Selected Components of ETVAX. |
|---|---|---|
| Started | 140 | 140 |
| Completed | 139 | 139 |
| Not completed | 1 | 1 |
The primary endpoint to be measured for each patient in the study is response (yes/no) to a vaccine. A vaccine responder will be defined by a ≥2-fold increase in IgA and/or IgG antibody levels against LTB in serum between post- compared to pre-immunization samples. The response rates (seroconversion rates) of IgA and/or IgG anti-LTB antibodies in serum will be derived and compared between the two treatment groups.
| Participants | The Wet Formulation of ETVAX. | The Partially Dried Formulation of Selected Components of ETVAX. |
|---|---|---|
| Vaccine Response | 116 | 110 |
Occurrence of solicited symptoms for six days after each vaccination (day of vaccination and five subsequent days).
| Participants | The Wet Formulation of ETVAX. | The Partially Dried Formulation of Selected Components of ETVAX. |
|---|---|---|
| Subjects who experienced solicited AEs within 6 days after first dose — Abdominal pain | 23 | 22 |
| Subjects who experienced solicited AEs within 6 days after first dose — Nausea | 17 | 20 |
| Subjects who experienced solicited AEs within 6 days after first dose — Vomiting | 3 | 3 |
| Subjects who experienced solicited AEs within 6 days after first dose — Loose stools/Diarrhea | 24 | 33 |
| Subjects who experienced solicited AEs within 6 days after first dose — Fever | 3 | 0 |
| Subjects who experienced solicited AEs within 6 days after first dose — No solicited symptom | 70 | 62 |
| Subjects who experienced solicited AEs within 6 days after second dose — Abdominal pain | 24 | 12 |
| Subjects who experienced solicited AEs within 6 days after second dose — Nausea | 22 | 20 |
| Subjects who experienced solicited AEs within 6 days after second dose — Vomiting | 4 | 5 |
| Subjects who experienced solicited AEs within 6 days after second dose — Loose stools/Diarrhea | 27 | 24 |
| Subjects who experienced solicited AEs within 6 days after second dose — Fever | 3 | 0 |
| Subjects who experienced solicited AEs within 6 days after second dose — No solicited symptom | 59 | 78 |
Evaluation if ETVAX® vaccination induces circulating antigen specific memory B- and/or T cells.
Results for this outcome have not been posted.
Collected over Collection of unsolicited AEs started with the first intervention with the study vaccine and continued until the last follow-up assessment 7 days (6-10 days) after study vaccine dose 2.. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| The Wet Formulation of ETVAX. | 0/140 (0%) | 0/140 (0%) | 107/140 (76.4%) |
| The Partially Dried Formulation of Selected Components of ETVAX. | 0/140 (0%) | 0/140 (0%) | 102/140 (72.9%) |
| Event | The Wet Formulation of ETVAX. | The Partially Dried Formulation of Selected Components of ETVAX. |
|---|---|---|
| HeadacheNervous system disorders | 43/140 | 40/140 |
| DiarrhoeaGastrointestinal disorders | 41/140 | 42/140 |
| Abdominal painGastrointestinal disorders | 36/140 | 30/140 |
| NauseaGastrointestinal disorders | 32/140 | 33/140 |
| FlatulenceGastrointestinal disorders | 19/140 | 14/140 |
| DysmenorrhoeaReproductive system and breast disorders | 13/140 | 5/140 |
| NasopharyngitisInfections and infestations | 12/140 | 11/140 |
| FatigueGeneral disorders | 7/140 | 5/140 |
| PyrexiaGeneral disorders | 7/140 | 0/140 |
| VomitingGastrointestinal disorders | 7/140 | 6/140 |
| Age, Continuous(Years) | The Wet Formulation of ETVAX. | The Partially Dried Formulation of Selected Components of ETVAX. | Total |
|---|---|---|---|
| Mean | 31.0 ± 9.70 | 32.2 ± 9.54 | 31.6 ± 9.62 |
| Sex: Female, Male(Participants) | The Wet Formulation of ETVAX. | The Partially Dried Formulation of Selected Components of ETVAX. | Total |
|---|---|---|---|
| Female | 86 | 87 | 173 |
| Male | 54 | 53 | 107 |
| Ethnicity (NIH/OMB)(Participants) | The Wet Formulation of ETVAX. | The Partially Dried Formulation of Selected Components of ETVAX. | Total |
|---|---|---|---|
| Hispanic or Latino | 1 | 1 | 2 |
| Not Hispanic or Latino | 139 | 139 | 278 |
| Unknown or Not Reported | 0 | 0 | 0 |
| Region of Enrollment(participants) | The Wet Formulation of ETVAX. | The Partially Dried Formulation of Selected Components of ETVAX. | Total |
|---|---|---|---|
| Sweden | 140 | 140 | 280 |
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Scandinavian Biopharma AB