A Phase 2 interventional study of Day 1 Dose (2×106 pfu) and Day 1 Dose (1×107 pfu) in Lassa Fever, sponsored by International AIDS Vaccine Initiative. Recruiting at 3 sites in 3 countries. Open to participants aged 6 Years to 70 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-10-23.
Sponsored by International AIDS Vaccine Initiative · Phase 2, Interventional, and Prevention
A Phase 2 Randomized, Double-Blinded, Placebo-Controlled Clinical Trial to Evaluate the Safety, Tolerability, and Immunogenicity of rVSV∆G-LASV-GPC Vaccine in Adults and Children Residing in West Africa
rVSVΔG-LASV-GPC is a candidate vaccine that has been shown to be safe and protects against LF disease in animals. The vaccine was studied in a Phase 1 trial and has been well tolerated and immunogenic. Phase 1 is complete. This Phase 2 trial will add to data from the Phase 1 trial to establish a broader profile of safety and immunogenicity in adults and expand the population to include a subset of adults with HIV infection as well as older adults and healthy children, in preparation for an efficacy trial in West Africa. Primary Objective: • To evaluate the safety and tolerability of rVSVΔG-LASV-GPC vaccine at 3 different dosage levels in adults. Secondary Objectives: • To determine binding LASV-GPC-specific antibody responses induced by rVSVΔG-LASV-GPC vaccine • To determine neutralizing LASV-GPC-specific antibody responses induced by rVSVΔG-LASV-GPC vaccine in a subset of participants in each group • To evaluate the magnitude and duration of the rVSVΔG-LASV-GPC vaccine viremia in plasma in a subset of participants. • To evaluate the magnitude and duration of the rVSVΔG-LASV-GPC vaccine shedding in saliva and urine, and possibly semen and cervicovaginal fluid, in a subset of participants Exploratory Objective • To explore the characteristics of the immune responses induced by rVSVΔG-LASV-GPC vaccine in a subset of participants
International AIDS Vaccine Initiative is the lead sponsor of 37 studies on the registry; 5 are open to participants now.
Of its 8 completed or terminated interventional studies of FDA-regulated products, 0 (0%) have results posted.
Counted across the registry records on this site, refreshed daily.
The criteria were revised on the registry on Oct 23, 2026. See what changed
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.
Additional Inclusion Criteria For HIV-Infected Participants
Additional Inclusion Criteria for Pediatric Participants
Exclusion Criteria:
For children 7 years of age and younger (or unable to follow pure tone audiometry procedure) "refer" test results as determined by OAE.
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.
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.
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.
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.
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
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.
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
A blood test of average blood sugar over the past two to three months, given as a percentage or in mmol/mol. 6.5% (48 mmol/mol) or more is the usual threshold for diabetes, normally confirmed by a second test.
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.
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 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.
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).
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
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 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.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
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.
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.
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.
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.
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.
Autoimmune disease
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
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.
Immunosuppression
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HbA1c
A blood test of average blood sugar over the past two to three months, given as a percentage or in mmol/mol. 6.5% (48 mmol/mol) or more is the usual threshold for diabetes, normally confirmed by a second test.
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.
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.
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.
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.
ULN (upper limit of normal)
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
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.
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.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
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.
Healthy Adults, 18-70yrs
Drug: Day 1 Dose (2×106 pfu) · Drug: Placebo
HIV-infected Adults, 18-50yrs
Drug: Day 1 Dose (2×106 pfu) · Drug: Placebo
Adolescents, 12 17yrs
Drug: Day 1 Dose (2×106 pfu) · Drug: Placebo
Children, 6-11yrs
Drug: Day 1 Dose (2×106 pfu) · Drug: Placebo
Healthy Adults, 18-70yrs
Drug: Day 1 Dose (1×107 pfu) · Drug: Placebo
HIV-infected Adults,18-50yrs
Drug: Day 1 Dose (1×107 pfu) · Drug: Placebo
Adolescents, 12 17yrs
Drug: Day 1 Dose (1×107 pfu) · Drug: Placebo
Children, 6-11yrs
Drug: Day 1 Dose (1×107 pfu) · Drug: Placebo
Children 6-11yrs
Drug: Placebo · Drug: Day 1 Dose (2×10^5 pfu)
rVSV∆G-LASV-GPC
rVSV∆G-LASV-GPC
Placebo
rVSV∆G-LASV-GPC
To evaluate the safety and tolerability of rVSV∆G-LASV-GPC vaccine at 3 different dosage levels in adults
Proportion of participants with Grade 3 or higher reactogenicity, ie, solicited AEs, within 14 days after IP administration
Time frame: 14 days
To evaluate the safety and tolerability of rVSV∆G-LASV-GPC vaccine at 3 different dosage levels in adults
Proportion of participants with IP-related Grade 2 or higher unsolicited AEs, including safety laboratory parameters, within 28 days of IP administration
Time frame: 28 days
To evaluate the safety and tolerability of rVSV∆G-LASV-GPC vaccine at 3 different dosage levels in adults
Proportion of participants with any Grade 2 or higher unsolicited AEs, including safety laboratory parameters, within 28 days of IP administration
Time frame: 28 days
To evaluate the safety and tolerability of rVSV∆G-LASV-GPC vaccine at 3 different dosage levels in adults
Proportion of participants with IP-related SAEs throughout the study period
Time frame: 7 months
To evaluate the safety and tolerability of rVSV∆G-LASV-GPC vaccine at 3 different dosage levels in adults
Proportion of participants with AESIs throughout the study period
Time frame: 7 months
To determine binding LASV-GPC-specific antibody responses induced by rVSV∆G-LASV-GPC vaccine
Proportion of participants with binding antibody responses to LASV-GPC
Time frame: 6 months/up to 30 months for subset of participants enrolled under earlier protocol versions
To determine binding LASV-GPC-specific antibody responses induced by rVSV∆G-LASV-GPC vaccine
Magnitude of binding antibody responses to LASV-GPC
Time frame: 6 months/up to 30 months for subset of participants enrolled under earlier protocol versions
To determine neutralizing LASV-GPC-specific antibody responses induced by rVSV∆G-LASV-GPC vaccine in a subset of participants in each group
Proportion of participants with neutralizing antibody responses against LASV
Time frame: 6 months/up to 30 months for subset of participants enrolled under earlier protocol versions
To determine neutralizing LASV-GPC-specific antibody responses induced by rVSV∆G-LASV-GPC vaccine in a subset of participants in each group
Magnitude of neutralizing antibody responses against LASV
Time frame: 6 months/up to 30 months for subset of participants enrolled under earlier protocol versions
To evaluate the magnitude and duration of the rVSV∆G-LASV-GPC vaccine viremia in plasma in a subset of participants
Magnitude and duration of rVSV∆G-LASV-GPC vaccine viremia by PCR, with PCR-positive samples cultured
Time frame: 6 months/up to 30 months for subset of participants enrolled under earlier protocol versions
To evaluate the magnitude and duration of the rVSVΔG-LASV-GPC vaccine shedding in saliva and urine, and possibly semen and cervicovaginal fluid, in a subset of participants
Magnitude and duration of rVSV∆G-LASV-GPC vaccine shedding in urine and saliva by PCR, with PCR-positive samples cultured
Time frame: 6 months/up to 30 months for subset of participants enrolled under earlier protocol versions
To evaluate the magnitude and duration of the rVSV∆G-LASV-GPC vaccine shedding in saliva and urine, and possibly semen and cervicovaginal fluid, in a subset of participants
Magnitude and duration of rVSV∆G-LASV-GPC vaccine shedding in semen and cervicovaginal secretions by PCR, with PCR-positive samples cultured
Time frame: 6 months/up to 30 months for subset of participants enrolled under earlier protocol versions
Plan to share: Undecided
No publications or documents are linked to this record.
Started Mar 2024 (actual). Primary completion is estimated for Jun 2027, 39 months after the start.
Since we started tracking on Sep 25, 2026, the dates moved once, on Oct 23, 2026: primary completion Dec 2026 → Jun 2027 and completion Apr 2027 → Jun 2027.
Earlier changes are on the record history on ClinicalTrials.gov ↗
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
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Lassa Fever
International AIDS Vaccine Initiative