Typhoid and Paratyphoid FeversPhase 1/2NCT00269295
TY800 Dose Escalation (Typhoid)
A Phase 1/2 study testing Ty800 in people with Typhoid and Paratyphoid Fevers, run by National Institute of Allergy and Infectious Diseases (NIAID) at 1 site in United States.
Trial summary
The purpose of this research study is to determine whether a new vaccine for typhoid fever is safe and effective. This study will also look at what effects (good and bad) this new vaccine, Ty800, has on the volunteers. Read more about this study
- Who is it for?
- Ages 18 to 45 yearsHealthy volunteers can take part
- Conditions the study is for
- Typhoid and Paratyphoid Fevers
- What is being tested?
- Ty800
- Type of treatment
- Vaccines, Pill or oral medicine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 47 participants
- Where
- 1 siteUnited States
- Study dates
- Feb 2006to Jan 2007
- Phase
- Phase 1/2
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 45 years
- All sexes
- Healthy volunteers accepted
- Adult
Who may be able to join
- Healthy men or women, aged 18 to 45 years, inclusive.
- Provide voluntary written informed consent prior to undergoing any study specific screening procedures.
- Must be willing to remain in the inpatient study unit for at least 10 days.
- Subjects must be of nonchildbearing potential, or if of childbearing potential (as determined by the investigator) must be using an effective licensed method of birth control (e.g., oral contraceptives; diaphragm or condom in combination with contraceptive jelly, cream, or foam; intrauterine contraceptive device; or Depo-Provera®; skin patch; vaginal ring or cervical cap or abstinence) for 30 days prior to vaccination and must agree to continue such precautions during the study and for 30 days after the final study visit. A highly effective method of birth control is defined as one that results in a low failure rate (i.e., less than 1 percent per year) when used consistently and correctly, such as implants, injectables, combined oral contraceptives, some intrauterine devices (IUDs), sexual abstinence, or a vasectomized partner. ICH Guidance for Industry M3 Nonclinical Safety Studies for the Conduct of Human Clinical Trials for Pharmaceuticals (April 1997). If the subject uses abstinence as a method of birth control a questionnaire will be used to assure abstinence.
- Have normal screening laboratories for SGPT (ALT), creatinine, sodium, potassium, total white blood count (WBC), hemoglobin, neutrophils, lymphocytes, platelets, urine protein and hematuria.
Who cannot join
- Positive serum pregnancy test at screening or at admission (Day 1). Women who are pregnant or lactating and women of childbearing potential who do not agree to use acceptable birth control methods.
- History of immunocompromised states, human immunodeficiency virus (HIV) or acquired immunodeficiency syndrome, autoimmune disease, leukemia, lymphoma, generalized malignancy, undergoing long-term chemotherapy, radiation therapy, or receiving systemic steroid therapy. A history of basal cell or squamous cell carcinoma cured by local excision more than 5 years ago will not be considered an exclusion criterion.
- Clinically significant history of cardiovascular disease, respiratory disease, gall bladder disease, endocrine disorder, liver disease, renal disease, gastrointestinal disease, sickle cell anemia, neurologic illness, psychiatric disorder requiring chronic medication or prior hospitalization.
- Presence of prosthetic cardiac valves or other intravascular or intra-articular prosthetic material.
- Presence of HIV antibody.
- Presence of hepatitis B surface antigen or hepatitis C antibody.
Show all 23Show fewer
- HLA-B27 or IgA deficiency.
- Presence of Salmonella species and/or bacterial or parasitic pathogens in a screening stool examination.
- History of travel to a S typhi endemic area within the last 5 years, history of raising a child from a S typhi endemic area, vaccination against typhoid fever, infection with S typhi, or participation in a typhoid fever clinical trial using S typhi or an S typhi vector at any time. United States, Canada, Europe, New Zealand and Australia are not considered endemic areas.
- Clinically abnormal screening electrocardiogram (ECG) defined as pathologic Q waves and significant ST-T wave changes; criteria for left ventricular hypertrophy; and any nonsinus rhythm excluding isolated premature atrial contractions.
- Known allergy or sensitivity to 2 or more of the following antibiotics: ciprofloxacin, amoxicillin, trimethoprim-sulfamethoxazole, chloramphenicol, ceftriaxone, or quinolones (e.g., enoxacin, lomefloxacin, ofloxacin, norfloxacin).
- Known allergy to any components of the Ty800 vaccine or buffer (sodium bicarbonate/ascorbic acid).
- Receipt of blood/blood products or immunoglobulins within 6 months prior to the screening visit. Donation of blood within 2 months.
- A change in the subject's normal stool pattern within 3 months prior to screening visit. A normal stool pattern is defined as at least once a week and less than 4 times a day.
- Regular (monthly or more often) use of laxatives including herbal laxatives.
- Any medical illness requiring new prescription medication or hospitalization during the 45-day screening period prior to admission to the inpatient facility or have a temperature greater than or equal to 38.0ºC during the inpatient period prior to administering the study vaccine.
- Use of antibiotics within 7 days prior to study product administration.
- Use of any H2 receptor antagonists (e.g., Tagamet®, Zantac®, Pepcid®), proton pump inhibitors (e.g., Prilosec® OTC, Protonix®, and Prevacid®), or prescription acid suppression medication or over-the-counter (OTC) antacids within 72 hours of study product administration.
- Subjects who are commercial food handlers, day care workers, or health care workers involved in direct patient contact. Subjects with young children (<2 years) at home or with household contacts who are immunocompromised, pregnant, or breast-feeding.
- Participation in any other investigational drug, device, or vaccine trial within the 30 days prior to screening or planned participation within 30 days after the final study visit.
- Subjects who are unable to pass a written test that describes typhoid fever and explains the requirements of the clinical trial.
- Any other condition or responsibility, such as a medical, psychiatric, or social condition or occupational responsibility that, in the judgment of the investigator, would interfere with or serve as a contradiction to the subject's participation in the protocol or assessment of the investigational product.
- Subjects who smoke and cannot stop smoking for the duration of the inpatient study. -Subjects will be excluded if their screening laboratory test results fall outside of the laboratory normal range with the exception that 1) WBC and neutrophil counts below the laboratory normals will be allowable if they are in keeping with the levels seen in a condition that is prevalent in our population known as benign ethnic neutropenia, 2) transaminase levels (ALT) below the lower limit of "normal" will also not be an exclusion criterion.
Trial locations and contacts
1 site in 1 country.
United States1 site
Cincinnati Children's Hospital Medical Center
Cincinnati, Ohio, 45229
About this study
Official title: A Randomized, Double-Blind, Placebo-Controlled, Dose Escalation, In-Patient Phase I/II Study to Determine the Safety and Immunogenicity of Ty800 in Healthy Adult Subjects
The purpose of this research study is to determine whether a new vaccine for typhoid fever is safe and effective. This study will also look at what effects (good and bad) this new vaccine, Ty800, has on the volunteers. The study will determine the highest dose of Ty800 that can be given without causing severe side effects. About 54 healthy males and females, ages 18-45 inclusive, in the Cincinnati metropolitan area will be enrolled in this study. They will be in the study for approximately 7 months, which includes a one month screening period, study product administration on Day 0, a 10-day hospital stay, an outpatient period on Days 9-28 with 4 follow-up visits, and safety follow-up phone calls at 2 and 6 months after hospital discharge. Researchers hope that this trial will help produce a vaccine that combines a high level of durable protective immunity with simplicity of administration and minimal reaction to the vaccine.
Read the detailed description
Typhoid fever is a generalized infection of the reticuloendothelial system (spleen, liver, and bone marrow), gut-associated lymphoid tissue and gall bladder caused by Salmonella enterica serovar Typhi (S typhi). Humans are the only known natural host and reservoir for S typhi. Typhoid bacilli are transmitted by the fecal-oral route by contaminated drinking water or food. The ideal typhoid vaccine would combine high levels of durable protective immunity with simplicity of administration and minimal reactogenicity. The primary objective of this study is to assess the safety of Ty800 oral typhoid vaccine when administered as a single dose over a range of doses (5 x 10^7, 5 x 10^8, and 5 x 10^9 cfu) in healthy adult subjects compared to placebo. The primary endpoint is safety of Ty800 at the dose levels administered compared to placebo as determined by absence of bacteremia, absence of the diagnosis of typhoid fever as confirmed by a positive blood culture for the Ty800 vaccine organism, and by verifying that the null phoP/phoQ phenotype is retained by the isolated shed vaccine organism. Safety variables will be assessed by the reported incidence of adverse events (AE), blood cultures, and changes in vital signs, physical examination, and routine laboratory parameters over time at each vaccine dose level compared to placebo. The secondary objectives of this study are: to evaluate the immunogenicity of a single oral dose administration of Ty800 over a range of doses in healthy adult subjects; to evaluate the Ty800 vaccine dose response by comparing the immunogenicity profiles of each dose level; and to evaluate the shedding profile of Ty800 by determining the quantity and duration of shedding for each dose level. The tertiary objectives of this study include: evaluating, in a substudy, single nucleotide polymorphisms (SNPs) in candidate genes, e.g., IL-8 and interferon gamma, that may influence the immune response or persistent shedding of the vaccine organism and evaluating the induction of memory B cells in the vaccinated subjects. This study is a randomized, double-blind, placebo-controlled, dose escalation, inpatient phase I/II clinical trial. Three dose levels of Ty800 a vaccine will be evaluated and compared to placebo. Prior to randomization and administration of study vaccine, subjects will undergo screening evaluations. Healthy subjects meeting study eligibility criteria will be admitted to an inpatient facility with appropriate isolation containment the day prior to randomization, and they will remain in the unit for approximately 10 consecutive days. Three cohorts of 18 volunteers, representing 3 escalating doses of Ty800 typhoid vaccine will be challenged. In each cohort, 12 volunteers will receive Ty800 as a single oral dose, and 6 volunteers will receive placebo. Dose escalation will occur in a stepwise fashion and will be dependent upon the assessment of safety parameters and by meeting criteria for advancement to the next dose. Participants will be involved in study related procedures for up to 7 months.
- Conditions
- Typhoid and Paratyphoid Fevers
- Being tested
- Ty800, Placebo
- Keywords
- Typhoid fever, S typhi, vaccine
- Medical subject headings
- Typhoid Fever, Paratyphoid Fever
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Ty800Biological
Live attenuated Ty800 S typhi oral vaccine is co-administered with a sodium bicarbonate buffer solution. Dosages: 5 X 10^7 cfu, 5 X 10^8 cfu, and 5 X 10^9 cfu.
PlaceboDrug
150 mL of the prepared sodium bicarbonate buffer solution. Placebo will look and taste essentially like the study product.
| Study group | Role | What they receive |
|---|---|---|
| Cohort 1: Arm 1 | Experimental | 12 subjects to receive vaccine dose 1: 5 X 10^7 cfu. Receives: Biological: Ty800 |
| Cohort 1: Arm 2 | Placebo comparator | 6 subjects to receive placebo. Receives: Drug: Placebo |
| Cohort 2: Arm 1 | Experimental | 12 subjects to receive vaccine dose 2: 5 X 10^8 cfu. Receives: Biological: Ty800 |
| Cohort 3: Arm 1 | Experimental | 12 subjects to receive vaccine dose 3: 5 X 10^9 cfu. Receives: Biological: Ty800 |
| Cohort 3: Arm 2 | Placebo comparator | 6 subjects to receive placebo. Receives: Drug: Placebo |
| Cohort 2: Arm 2 | Placebo comparator | 6 subjects to receive placebo. Receives: Drug: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
Assess the safety of Ty800 oral typhoid vaccine when administered as a single dose over a range of doses (5 x 10^7, 5 x 10^8, 5 x 10^9 cfu) in healthy adult subjects compared to placebo.
Measured: Duration of study.
Secondary outcomes (3)
To evaluate the shedding profile of Ty800 by determining the quantity and duration of shedding for each dose level. Spread of the vaccine organism to placebo subjects will also be monitored as an outcome variable.
Measured: Days 1-8, 11, 14, and 28.
To evaluate the immunogenicity of the single oral dose administration of Ty800 over a range of doses in healthy adult subjects.
Measured: At intervals after vaccination between Days 7 through 28.
To evaluate the Ty800 vaccine dose response by comparing the immunogenicity profiles of each dose level.
Measured: At intervals after vaccination between Days 7 through 28.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted23 Dec 2005 (estimated)
- Study startFeb 2006
- Primary completionJan 2007
- Study completionJan 2007
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Typhoid and Paratyphoid FeversStudies of the same condition, open and under way.
- More trials run by National Institute of Allergy and Infectious Diseases (NIAID)The sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 1/2
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind
- Who is masked
- Participant, Investigator
- Enrolment
- 47 participants (actual)
Sponsor and investigators
- Sponsor type
- US National Institutes of Health
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT00269295
- Sponsor's protocol ID
- 04-084
- Status last verified
- Feb 2010
- First submitted
- 22 Dec 2005
- Last updated
- 10 Jun 2011
- Results posted
- No
Study at a glance
From the registry record, last updated by the sponsor on 10 Jun 2011. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Randomized, Double-Blind, Placebo-Controlled, Dose Escalation, In-Patient Phase I/II Study to Determine the Safety and Immunogenicity of Ty800 in Healthy Adult Subjects
- ClinicalTrials.gov ID
- NCT00269295
- Acronym / sponsor ID
- 04-084
- Conditions
- Typhoid and Paratyphoid Fevers
- Keywords
- Typhoid fever, S typhi, vaccine
- Phase
- Phase 1/2
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 47 participants (actual)
- Lead sponsor
- National Institute of Allergy and Infectious Diseases (NIAID)US National Institutes of Health
- Study start
- Feb 2006
- Primary completion
- Jan 2007 (actual)
- Study completion
- Jan 2007 (actual)
- First posted
- 23 Dec 2005 (estimated)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The purpose of this research study is to determine whether a new vaccine for typhoid fever is safe and effective. This study will also look at what effects (good and bad) this new vaccine, Ty800, has on the volunteers. The study will determine the highest dose of Ty800 that can be given without causing severe side effects. About 54 healthy males and females, ages 18-45 inclusive, in the Cincinnati metropolitan area will be enrolled in this study. They will be in the study for approximately 7 months, which includes a one month screening period, study product administration on Day 0, a 10-day hospital stay, an outpatient period on Days 9-28 with 4 follow-up visits, and safety follow-up phone calls at 2 and 6 months after hospital discharge. Researchers hope that this trial will help produce a vaccine that combines a high level of durable protective immunity with simplicity of administration and minimal reaction to the vaccine.
Detailed description
Typhoid fever is a generalized infection of the reticuloendothelial system (spleen, liver, and bone marrow), gut-associated lymphoid tissue and gall bladder caused by Salmonella enterica serovar Typhi (S typhi). Humans are the only known natural host and reservoir for S typhi. Typhoid bacilli are transmitted by the fecal-oral route by contaminated drinking water or food. The ideal typhoid vaccine would combine high levels of durable protective immunity with simplicity of administration and minimal reactogenicity. The primary objective of this study is to assess the safety of Ty800 oral typhoid vaccine when administered as a single dose over a range of doses (5 x 10^7, 5 x 10^8, and 5 x 10^9 cfu) in healthy adult subjects compared to placebo. The primary endpoint is safety of Ty800 at the dose levels administered compared to placebo as determined by absence of bacteremia, absence of the diagnosis of typhoid fever as confirmed by a positive blood culture for the Ty800 vaccine organism, and by verifying that the null phoP/phoQ phenotype is retained by the isolated shed vaccine organism. Safety variables will be assessed by the reported incidence of adverse events (AE), blood cultures, and changes in vital signs, physical examination, and routine laboratory parameters over time at each vaccine dose level compared to placebo. The secondary objectives of this study are: to evaluate the immunogenicity of a single oral dose administration of Ty800 over a range of doses in healthy adult subjects; to evaluate the Ty800 vaccine dose response by comparing the immunogenicity profiles of each dose level; and to evaluate the shedding profile of Ty800 by determining the quantity and duration of shedding for each dose level. The tertiary objectives of this study include: evaluating, in a substudy, single nucleotide polymorphisms (SNPs) in candidate genes, e.g., IL-8 and interferon gamma, that may influence the immune response or persistent shedding of the vaccine organism and evaluating the induction of memory B cells in the vaccinated subjects. This study is a randomized, double-blind, placebo-controlled, dose escalation, inpatient phase I/II clinical trial. Three dose levels of Ty800 a vaccine will be evaluated and compared to placebo. Prior to randomization and administration of study vaccine, subjects will undergo screening evaluations. Healthy subjects meeting study eligibility criteria will be admitted to an inpatient facility with appropriate isolation containment the day prior to randomization, and they will remain in the unit for approximately 10 consecutive days. Three cohorts of 18 volunteers, representing 3 escalating doses of Ty800 typhoid vaccine will be challenged. In each cohort, 12 volunteers will receive Ty800 as a single oral dose, and 6 volunteers will receive placebo. Dose escalation will occur in a stepwise fashion and will be dependent upon the assessment of safety parameters and by meeting criteria for advancement to the next dose. Participants will be involved in study related procedures for up to 7 months.
Study design
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind (participant, investigator)
- Number of arms
- 6
| Arm | Type | Receives |
|---|---|---|
| Cohort 1: Arm 1 | Experimental | Biological: Ty80012 subjects to receive vaccine dose 1: 5 X 10^7 cfu. |
| Cohort 1: Arm 2 | Placebo comparator | Drug: Placebo6 subjects to receive placebo. |
| Cohort 2: Arm 1 | Experimental | Biological: Ty80012 subjects to receive vaccine dose 2: 5 X 10^8 cfu. |
| Cohort 3: Arm 1 | Experimental | Biological: Ty80012 subjects to receive vaccine dose 3: 5 X 10^9 cfu. |
| Cohort 3: Arm 2 | Placebo comparator | Drug: Placebo6 subjects to receive placebo. |
| Cohort 2: Arm 2 | Placebo comparator | Drug: Placebo6 subjects to receive placebo. |
Who may qualify
- Ages
- 18 to 45 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (5 listed)
- Healthy men or women, aged 18 to 45 years, inclusive.
- Provide voluntary written informed consent prior to undergoing any study specific screening procedures.
- Must be willing to remain in the inpatient study unit for at least 10 days.
- Subjects must be of nonchildbearing potential, or if of childbearing potential (as determined by the investigator) must be using an effective licensed method of birth control (e.g., oral contraceptives; diaphragm or condom in combination with contraceptive jelly, cream, or foam; intrauterine contraceptive device; or Depo-Provera®; skin patch; vaginal ring or cervical cap or abstinence) for 30 days prior to vaccination and must agree to continue such precautions during the study and for 30 days after the final study visit. A highly effective method of birth control is defined as one that results in a low failure rate (i.e., less than 1 percent per year) when used consistently and correctly, such as implants, injectables, combined oral contraceptives, some intrauterine devices (IUDs), sexual abstinence, or a vasectomized partner. ICH Guidance for Industry M3 Nonclinical Safety Studies for the Conduct of Human Clinical Trials for Pharmaceuticals (April 1997). If the subject uses abstinence as a method of birth control a questionnaire will be used to assure abstinence.
- Have normal screening laboratories for SGPT (ALT), creatinine, sodium, potassium, total white blood count (WBC), hemoglobin, neutrophils, lymphocytes, platelets, urine protein and hematuria.
Key exclusion criteria (23 listed)
- Positive serum pregnancy test at screening or at admission (Day 1). Women who are pregnant or lactating and women of childbearing potential who do not agree to use acceptable birth control methods.
- History of immunocompromised states, human immunodeficiency virus (HIV) or acquired immunodeficiency syndrome, autoimmune disease, leukemia, lymphoma, generalized malignancy, undergoing long-term chemotherapy, radiation therapy, or receiving systemic steroid therapy. A history of basal cell or squamous cell carcinoma cured by local excision more than 5 years ago will not be considered an exclusion criterion.
- Clinically significant history of cardiovascular disease, respiratory disease, gall bladder disease, endocrine disorder, liver disease, renal disease, gastrointestinal disease, sickle cell anemia, neurologic illness, psychiatric disorder requiring chronic medication or prior hospitalization.
- Presence of prosthetic cardiac valves or other intravascular or intra-articular prosthetic material.
- Presence of HIV antibody.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Ty800Live attenuated Ty800 S typhi oral vaccine is co-administered with a sodium bicarbonate buffer solution. Dosages: 5 X 10^7 cfu, 5 X 10^8 cfu, and 5 X 10^9 cfu. | Biological | Cohort 1: Arm 1, Cohort 2: Arm 1, Cohort 3: Arm 1 |
| Placebo150 mL of the prepared sodium bicarbonate buffer solution. Placebo will look and taste essentially like the study product. | Drug | Cohort 1: Arm 2, Cohort 2: Arm 2, Cohort 3: Arm 2 |
Primary outcome
Assess the safety of Ty800 oral typhoid vaccine when administered as a single dose over a range of doses (5 x 10^7, 5 x 10^8, 5 x 10^9 cfu) in healthy adult subjects compared to placebo.
Time frame: Duration of study.
3 secondary outcomes
To evaluate the shedding profile of Ty800 by determining the quantity and duration of shedding for each dose level. Spread of the vaccine organism to placebo subjects will also be monitored as an outcome variable.
Time frame: Days 1-8, 11, 14, and 28.
To evaluate the immunogenicity of the single oral dose administration of Ty800 over a range of doses in healthy adult subjects.
Time frame: At intervals after vaccination between Days 7 through 28.
To evaluate the Ty800 vaccine dose response by comparing the immunogenicity profiles of each dose level.
Time frame: At intervals after vaccination between Days 7 through 28.
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 10 Jun 2011.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 1/2 study testing Ty800 in people with Typhoid and Paratyphoid Fevers, run by National Institute of Allergy and Infectious Diseases (NIAID) at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 23 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 10 Jun 2011. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this combined phase mean?
Phase 1 studies test a treatment in a small group of people for the first time or in a new way, mainly to check safety and find the right dose.
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Assess the safety of Ty800 oral typhoid vaccine when administered as a single dose over a range of doses (5 x 10^7, 5 x 10^8, 5 x 10^9 cfu) in healthy adult subjects compared to placebo. (time frame: Duration of study.). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 10 Jun 2011; AzTrials last refreshed its copy on 27 Oct 2026.