A Phase 1 interventional study of 3.75 µg Dose of CDC-9 Inactivated Rotavirus Vaccine (IRV) and 7.5 µg Dose of CDC-9 Inactivated Rotavirus Vaccine (IRV) in Rotavirus Infections, sponsored by Centers for Disease Control and Prevention. Completed at 1 site in United States. Open to participants aged 18 Years to 45 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-05-26.
Sponsored by Centers for Disease Control and Prevention · Phase 1, Interventional, and Prevention
This is a study of CDC-9 inactivated rotavirus vaccine (IRV) for intramuscular administration (IM) in healthy adults aged 18 to 45 years at two dose levels in a 3-dose series. The purpose is to determine if it is safe and if the recipient's immune system responds to the vaccine.
Rotavirus remains an important cause of gastroenteritis and accounted for 19% of diarrhea-related deaths worldwide in 2019, the majority of which were in low and lower-middle income countries. Although live-attenuated vaccines for rotavirus are available for infants, the immunogenicity and vaccine effectiveness in low- and middle-income countries, where morbidity is highest, is suboptimal. Developing rotavirus vaccination strategies with improved immunogenicity could be advantageous in resource-limited settings.
To improve the safety and efficacy of oral rotavirus vaccines, Centers for Disease Control and Prevention (CDC) scientists have developed a human rotavirus strain CDC-9 (G1P[8]\^9) that grows to high titer in Vero cells and shows structural stability during manufacturing process. The strain is a single gene natural reassortant with the VP3 gene derived naturally from a G2P[4] virus and the other 10 genes from a G1P[8] virus, the most common genotype throughout the world. Purified CDC-9 particles when inactivated by heat and administered intramuscularly, induced strong serum antibody response, and showed dose sparing effect in mice and rats. This inactivated rotavirus vaccine (IRV) also induced intestinal immunity in mice and prevented fecal shedding in gnotobiotic pigs against rotavirus. When given in combination with inactivated polio vaccine in mice it did not impair immune responses to either rotavirus or poliovirus serotypes 1, 2, and 3. Vaccination with IRV has shown to be safe and immunogenic in animal studies.
A rotavirus vaccine with greater efficacy and stronger immunogenic response could further reduce infant mortality and morbidity, and a parenterally administered rotavirus vaccine could minimize interactions from co-administration with polio vaccination. Given the lower immunogenicity and vaccine efficacy of the oral rotavirus vaccines currently licensed by the US and in developing countries and approved for use by the World Health Organization (WHO), the IRV presents an opportunity to further prevent rotavirus-associated gastroenteritis in infants.
This will be a Phase 1, randomized, observer blinded, dose escalating, placebo-controlled clinical trial in which healthy adults (18 - 45 years of age) will receive inactivated IRV or placebo administered through intramuscular injection to determine the safety, reactogenicity, and immunogenicity. Cohorts of 25 individuals (20 vaccine recipients and 5 placebo recipients) per dose level will receive three intramuscular injections four weeks apart. The two dose levels of vaccine to test will be 3.75 microgram (μg) or 7.5 μg.
Subjects will receive a total of 3 IRV doses at Days 1, 29, and 57. Subjects will be monitored for approximately 6 months after the third-dose vaccination. They will be followed for solicited (local and systemic) adverse events (AEs) through 7 days after each dose of vaccine. Unsolicited AEs will be collected through Day 85. Immunogenicity labs will be obtained before each vaccine dose, 7 days after each vaccine dose, 28 days after each vaccine dose, 35 days after the first dose, and at the last study visit on Day 237 (durability of response). Serious Adverse Events (SAEs) will be followed from Vaccination on Day 1 through the last study visit on Day 237.
104 studies on the registry are indexed under Rotavirus Infections; 3 are open to participants now.
This study's enrollment of 50 is below the median of 403 across 69 interventional studies indexed under Rotavirus Infections.
Browse Rotavirus Infections studies →Centers for Disease Control and Prevention is the lead sponsor of 275 studies on the registry; 2 are open to participants now.
Of its 11 completed or terminated interventional studies of FDA-regulated products, 8 (73%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Women of ¹ must agree to use or have practiced true abstinence² or use at least one acceptable primary form of .³,⁴
Note: These criteria are applicable to females in a heterosexual relationship and child-bearing potential (i.e., the criteria do not apply to subjects in a same sex relationship).¹Not of childbearing potential - females (defined as having a history of amenorrhea for at least one year) or a documented status as being surgically sterile (hysterectomy, bilateral oophorectomy, tubal ligation/salpingectomy, or Essure® placement). ²True abstinence is 100% of time no sexual intercourse (male's penis enters the female's vagina). ³Acceptable forms of primary contraception include monogamous relationship with a vasectomized partner who has been vasectomized for 180 days or more prior to the subject's first vaccination, intrauterine devices, birth control pills, and injectable/implantable/insertable hormonal birth control products. ⁴Must use at least one acceptable primary form of contraception for at least 30 days prior to the first vaccination and at least one acceptable primary form of contraception for 60 days after the last vaccination.
Male subjects of childbearing potential⁵: use of condoms to ensure effective contraception with a female partner of childbearing potential from first vaccination until 60 days after the last vaccination.
⁵Biological males who are post-pubertal and considered fertile until permanently sterile by bilateral orchiectomy or vasectomy.
Exclusion Criteria:
Has any medical disease or condition that, in the opinion of the site PI or appropriate sub-investigator, precludes study participation.⁶
⁶Including acute, subacute, intermittent, or chronic medical disease or condition that would place the subject at an unacceptable risk of injury, render the subject unable to meet the requirements of the protocol, or may interfere with the evaluation of responses or the subject's successful completion of this trial. Chronic medical conditions which are stable, with no escalation in medication doses or new medications administered in the preceding 3 months, will not be considered exclusionary.
Currently enrolled in or plans to participate in another clinical trial with an agent⁷ that will be received during the study-reporting period.
⁷Including licensed or unlicensed vaccine, drug, biologic, device, blood product, or medication.
Chronic use (more than 14 continuous days) of any medications that may be associated with impaired immune responsiveness.⁸
⁸Including, but not limited to, systemic exceeding 10 mg/day of prednisone equivalent, allergy injections, immunoglobulin, interferon, immunomodulators, cytotoxic drugs, or other similar or toxic drugs during the preceding 6-month period prior to vaccine administration (Day 1). The use of low dose topical, ophthalmic, inhaled, and intranasal steroid preparations will be permitted.
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
The number of neutrophils, white blood cells that help fight infection, in a given amount of blood. Too few raises the risk of infection.
It is a count, not a percentage of the white cells. Limits are written in units that mean the same: ≥ 1.5 × 10⁹/L is ≥ 1,500 per mm³ (µL). Each lab has its own reference range.
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Vaccines made with a weakened form of the germ, such as measles–mumps–rubella (MMR), chickenpox and yellow fever. They can be risky when the immune system is weakened. Flu injections are not live; the nasal flu spray is.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hemoglobin (Hb)
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Platelets
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Absolute neutrophil count (ANC)
The number of neutrophils, white blood cells that help fight infection, in a given amount of blood. Too few raises the risk of infection.
It is a count, not a percentage of the white cells. Limits are written in units that mean the same: ≥ 1.5 × 10⁹/L is ≥ 1,500 per mm³ (µL). Each lab has its own reference range.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ALT and AST (liver enzymes)
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Bilirubin
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Postmenopausal
Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis B tests
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis C tests
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Live vaccines
Vaccines made with a weakened form of the germ, such as measles–mumps–rubella (MMR), chickenpox and yellow fever. They can be risky when the immune system is weakened. Flu injections are not live; the nasal flu spray is.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
20 healthy adults will be administered via IM injection a single dose of IRV at days 1, 29 and 57
Biological: 3.75 µg Dose of CDC-9 Inactivated Rotavirus Vaccine (IRV) · Other: Placebo
20 healthy adults will be administered via IM injection a single dose of IRV at days 1, 29 and 57
Biological: 7.5 µg Dose of CDC-9 Inactivated Rotavirus Vaccine (IRV) · Other: Placebo
CDC-9 IRV adjuvanted with alhydrogel for IM administration in 0.5 mL is comprised of single human rotavirus for protection against rotavirus infection
CDC-9 IRV adjuvanted with alhydrogel for IM administration in 0.5 mL is comprised of single human rotavirus for protection against rotavirus infection
0.5 mL sterile saline administered via IM injection
Any unsolicited adverse events
The number of vaccine-related unsolicited adverse events following each vaccination. Unsolicited AEs will be collected continuously from vaccination on Day 1 through 28 days after the last vaccination (Day 85)
Time frame: Up to Day 29 following each vaccination or placebo
Any serious adverse events
The number vaccine-related serious adverse events from vaccination until end of the study. SAEs will be collected from Day 1 (after study product administration) through the last study visit (Day 237)
Time frame: Up to end of the study (Day 237)
Any solicited site reactions from vaccination
The subject will be provided with a memory aid, thermometer and ruler and will be instructed to record the presence of solicited local injection site symptoms and oral temperature through the 7 days after each vaccine
Time frame: Up to Day 8 following vaccination or placebo
Any solicited systemic reactions from vaccination
The subject will be provided with a memory aid, thermometer and ruler and will be instructed to record the presence of solicited systemic symptoms and oral temperature through the 7 days after each vaccine
Time frame: Up to Day 8 following vaccination or placebo
Any new-onset medical conditions (NOMC)
The number of new-onset medical conditions (NOMC) from first vaccination until end of the study
Time frame: Day 1 vaccination or placebo through end of the study (Day 237)
Any medically attended adverse events (MAAEs) from first vaccination until end of the study
The number of medically attended adverse events (MAAES)
Time frame: From Day 1 vaccination or placebo through the end of the study (Day 237)
Percentage of Subjects with Rotavirus IgG or Neutralizing Antibody Seroconversion
Seroconversion defined as a four-fold increase in antibody titers between baseline to 4 weeks post 3rd vaccination
Time frame: Baseline (Day 0) to 4 weeks post 3rd vaccination (Day 85)
Geometric Mean Titer (GMT) of rotavirus Immunoglobulin G (IgG) and Neutralizing Antibody Titer
Measured from sera to be collected from both cohorts on Day 85
Time frame: 4 weeks post 3rd vaccination (Day 85)
Geometric Mean Fold Rise (GMFR) of rotavirus Immunoglobulin G (IgG) and Neutralizing Antibody Titer
Measures from sera to be collected from both cohorts on Day 85
Time frame: 4 weeks post 3rd vaccination (Day 85)
Percentage of Subjects with Rotavirus Immunoglobulin A (IgA) Seroresponses
Seroconversion defined as four-fold change in antibody titers between baseline to 4 weeks post 3rd vaccination
Time frame: Baseline (Day 0) to 4 weeks post 3rd vaccination (Day 85)
Geometric mean titer (GMT) of Rotavirus Immunoglobulin A (IgA)
Measured from sera to be collected from both cohorts on Day 85
Time frame: 4 weeks post 3rd vaccination (Day 85)
Geometric mean fold rise (GMFR) in rotavirus IgA antibody
Measured from sera to be collected from both cohorts from baseline (Day 0) to Day 85
Time frame: From baseline (Day 0) to 4 weeks post 3rd vaccination (Day 85)
Percentage of Subjects with Rotavirus Immunoglobulin A (IgA), Immunoglobulin G (IgG) or Neutralizing Antibody Seroconversion
Measured from sera collected on Days 0, 8, 29, 36, 57, 65, and 237 (before the first vaccination and 4 weeks after each vaccination)
Time frame: Days 0, 8, 29, 36, 57, 65, and 237
Geometric mean titer (GMT) of Rotavirus Immunoglobulin A (IgA), Immunoglobulin G (IgG) or Neutralizing Antibody
Measured from sera collected from both groups during scheduled clinic visits on Days 0, 8, 29, 36, 57, 65, and 237
Time frame: Days 0, 8, 29, 36, 57, 65, and 237
Geometric Mean Fold Rise (GMFR) for Rotavirus Immunoglobulin A (IgA), Immunoglobulin G (IgG) or Neutralizing Antibody
Measured from sera collected from both groups during scheduled clinic visits on Days 0, 8, 29, 36, 57, 65, and 237
Time frame: Days 0, 8, 29, 36, 57, 65, and 237
PDFs hosted by the registry, ClinicalTrials.gov.
Plan to share: No
Ran from Aug 2024 to primary completion in Feb 2026, 17 months.
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This study is completed, as verified in May 2026. You cannot join it, but the record below documents what was studied.
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