SmallpoxPhase 2/3NCT05846243

Study on Immunogenicity, Reactogenicity and Safety of the VACΔ6 Vaccine in Volunteers Aged 18-60 Years

A Phase 2/3 study testing VAC∆6 vaccine (10⁷ PFU), VAC∆6 vaccine (10⁶ PFU) and Live Smallpox Vaccine in people with Smallpox and Monkeypox, run by Federal Budgetary Research Institution State Research Center of Virology and Biotechnology "Vector" at 2 sites in Russia.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record

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Trial summary

The Aim: Study immunogenicity, confirm the safety and tolerability of different schedules of vaccination with "live cell-based vaccine against smallpox and other orthopoxvirus infections (VAC∆6 vaccine) based on vaccinia virus" using a complex of clinical and laboratory-instrumental techniques. Read more about this study

Who is it for?: Ages 18 to 60 yearsHealthy volunteers can take part
Conditions the study is for: Smallpox, Monkeypox, Cowpox
What is being tested?: VAC∆6 vaccine (10⁷ PFU), VAC∆6 vaccine (10⁶ PFU) and Live Smallpox Vaccine
Type of treatment: Vaccines, Injection or infusion
Could I receive a placebo?: Yes, some participants may receive a placebo
How many people: 334 participants
Where: 2 sitesRussia
Study dates: 1 Oct 2021to 1 Apr 2022
Phase: Phase 2/3
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 60 years
All sexes
Healthy volunteers accepted
Adult

Who may be able to join

Signed and dated informed consent of a volunteer to participate in a clinical trial obtained prior to any of the study procedures.
A verified diagnosis of "healthy" according to standard clinical, laboratory and instrumental methods of examination.
Age from 18 to 60 inclusive.
Body mass index from 18.5 to 30 kg/m3.
Ability to attend all scheduled visits and all scheduled procedures and examinations.
Consent of volunteers to use effective methods of contraception throughout the study, including the period of observation for possible post-vaccination reactions.

Who cannot join

Hypersensitivity to any component of the product, allergy to vaccine components.
Pregnancy or breastfeeding.
The military.
Persons in custody in detention facilities and those serving sentences in correctional facilities.
Children under 18.
Acute infectious or non-infectious diseases, exacerbation of chronic diseases less than 4 weeks prior to the study.

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Tuberculosis (pulmonary and extrapulmonary).
Skin diseases: a) common dermatoses (pemphigus, psoriasis, eczema, atopic dermatitis), including the history of dermatoses; other acute and chronic diseases or impaired skin cover (burns, impetigo, herpes, herpes zoster/chicken pox, pustular diseases).
Immunosuppressive conditions: congenital or acquired immunodeficiency syndrome (including HIV infection), leukemia, malignant neoplasms, organ transplantation, cellular and humoral immunodeficiencies.
Immunosuppressive therapy: treatment with antimetabolites, high doses of corticosteroids for 14 days or more, radio and x-ray therapy, etc.
Regular medication intake less than 2 weeks before the start of the study.
Taking immunoglobulin drugs or blood products within the last 3 months before the start of the study.
Donation (450 ml of blood or plasma or more) less than 2 months before the start of the study.
Cardiovascular diseases: decompensated heart defects, subacute bacterial endocarditis, myocarditis, pericarditis, stage 2-3 hypertension, angina pectoris, myocardial infarction; other forms of pathology: stage 1 hypertension, well-controlled heart defects, angina pectoris (mild forms).
Diseases of the kidneys and urinary tract: diffuse glomerulonephritis, congenital nephropathy, chronic renal failure, pyelonephritis, toxic nephropathy (transient).
Diseases of the digestive system: cirrhosis of the liver, chronic hepatitis, hepatocerebral dystrophy, acute and chronic pancreatitis, diseases of the biliary tract, gastric ulcer and duodenal ulcer, ulcerative colitis.
Diseases of the endocrine system: diabetes mellitus, severe forms of thyrotoxicosis and adrenal insufficiency or dysfunction, thymomegaly, congenital enzymopathy.
Systemic connective tissue diseases: systemic lupus erythematosus, discoid lupus, rheumatism, rheumatoid arthritis, systemic vasculitis, systemic scleroderma.
Blood diseases: leukemia, Hodgkin's disease, aplastic anemia, hemophilia, Werlhof's disease; hemolytic conditions; deficiency anemia.
Allergic diseases: bronchial asthma; asthmatic bronchitis, asthmatic syndrome (associated with a respiratory infection); severe anaphylactic reactions (shock, angioedema of the larynx, etc.) to a variety of food, drug and other allergens; allergic reactions to individual allergens (various rashes, clinical disorders, etc.).
Diseases of the ear, throat, nose: chronic tonsillitis and adenoiditis requiring surgical treatment; chronic otitis.
Surgery within the previous 2 months.
Participation in other clinical trials less than 3 months prior to study enrollment.
Persons with alcohol, drug or drug addiction. Drinking more than 10 units of alcohol per week (1 unit of alcohol is equivalent to ½ liter of beer, 200 ml of wine or 50 ml of alcohol) or a history of alcoholism, drug addiction, drug abuse.
Mental illness and neurasthenia.
Previous treatment with human immunoglobulin preparations, if less than 6 months have passed since the treatment.
Failure to meet inclusion criteria.
Vaccination with any vaccine less than 2 months prior to study entry.
Premenopausal women (last menstrual period ≤ 1 year prior to signing the informed consent) who are not surgically sterile.
Women who have reproductive potential and do not use or plan to use approved birth control products throughout the study and do not agree to urine pregnancy testing while participating in the study. Acceptable birth control methods include extrauterine devices, oral, implanted, or injectable contraceptives.
Nervous and mental diseases: injuries of the central nervous system (CNS) with residual effects, encephalitis and encephalomyelitis (including post-vaccination), meningitis, polyradiculoneuritis (including the history of polyradiculoneuritis), epilepsy, decompensated or subcompensated hydrocephalus, demyelinating and degenerative lesions of the nervous system (muscle degeneration, etc.), stroke; compensated hydrocephalus, Down's disease, Little's disease, CNS trauma without residual effects, history of febrile convulsions, mental illness.
Positive analysis for HIV, viral hepatitis B and C, lues.
Other сoncomitant diseases that, in the opinion of the investigator, may interfere with the aims of the study.
Serious post-vaccination reactions/complications associated with any previous vaccination.

Trial locations and contacts

2 sites in 1 country.

Russia2 sites

Federal State Budgetary Institution of Healthcare "Medical and Sanitary Unit No. 163 of the Federal Medical and Biological Agency" (FGBUZ MSCH-163, FMBA of Russia)
Kol'tsovo, Novosibirsk Oblast, 630559
State Budgetary Health Institution of the Novosibirsk Region "Municipal Infectious Disease Clinical Hospital No. 1"
Novosibirsk, 630099

Other trials in Russia

About this study

Official title: Double-blind, Comparative, Randomized, Placebo-controlled Study on Immunogenicity, Reactogenicity and Safety of Live Cell-based Vaccine Against Smallpox and Other Orthopoxvirus Infections (VACΔ6 Vaccine) in Volunteers Aged 18-60 Years

The Aim:

Study immunogenicity, confirm the safety and tolerability of different schedules of vaccination with "live cell-based vaccine against smallpox and other orthopoxvirus infections (VAC∆6 vaccine) based on vaccinia virus" using a complex of clinical and laboratory-instrumental techniques.

The research tasks are to:

To study the immunological activity of a single VAC∆6 vaccine dose of 1x10⁷ plaque-forming units (PFU).
To study the immunological activity of two VAC∆6 vaccine doses (given 28 days apart) of 1x10⁶ PFU.
Assess the safety of different VAC∆6 vaccination schedules using a set of clinical and laboratory-instrumental techniques (thermometry, measurement of blood pressure, heart and lung auscultation, ECG, common blood and urine tests, biochemical, immunological and virological studies).
Assess the reactogenicity of different VAC∆6 vaccination schedules (number of local and systemic reactions, the percentage of those vaccinated with systemic and local reactions of various severity degrees).
To identify VAC∆6 vaccine-associated adverse events.
Study cell-mediated immunity induced by different VAC∆6 vaccination schedules.
Determine the presence of the virus in specific skin formations (crusts, pustules), saliva, blood and urine.
Evaluate the protective efficacy of one and two doses of the studied VAC∆6 vaccine.

Read the detailed description

This is a Double-blind, Comparative, Randomized, Placebo-controlled Study on Immunogenicity, Reactogenicity and Safety of Live Cell-Based Vaccine Against Smallpox and Other Orthopoxvirus Infections (VAC∆6 Vaccine) Based on Vaccinia Virus in 18-60-year-old Volunteers.

The study included 334 healthy volunteers of both sexes aged 18-60 years who met the inclusion criteria and had no exclusion criteria.

The study was carried out in two stages:

The first stage is an open comparative study of the safety, reactogenicity, immunological activity and protective efficacy of VAC∆6 vaccine in parallel groups of 30 volunteers aged 18 to 60 who met the inclusion criteria. Volunteers were divided into two groups:

Group 1: 15 volunteers who received a single intradermal VAC∆6 dose of 1x10⁷ PFU. Live smallpox vaccine was administered by scarification 2 months after the vaccination.
Group 2: 15 volunteers who received two intradermal VAC∆6 doses of 1x10⁶ PFU (given 28 days apart). Live smallpox vaccine was administered by scarification one month after the full vaccination series.

The second stage is a Double-blind, Comparative, Randomized, Placebo-controlled study on Immunogenicity, Reactogenicity, and Safety of the VAC∆6 Vaccine in Parallel Groups. Randomization was carried out using the envelope method. The sealed opaque envelopes included in the Investigator's File were distributed to the clinical sites in the required quantity prior to the start of the study.

Substances were submitted for testing in encrypted form. The encryption technique was chosen and implemented by the sponsor - FBRI SRC VB "Vector", Rospotrebnadzor. Decryption was carried out after study report submission to the Federal Budgetary Research Institution, State Research Center of Virology and Biotechnology "Vector", Rospotrebnadzor.

A total of 304 volunteers aged 18-60 took part in the second stage of the clinical study, of which 158 were men and 146 were women, who met the inclusion criteria and had no exclusion criteria. The volunteers were assigned to study sites as follows:

FGBUZ MSCH-163, FMBA Russia - 272 volunteers randomized into four groups:

Group 3: 76 volunteers who received two intradermal VAC∆6 doses of 10⁶ PFU/0.2 ml (given 28 days apart);
Group 4: 76 volunteers who received two intradermal placebo doses of 0.2 ml (given 28 days apart);
Group 5: 60 volunteers who received a single intradermal VAC∆6 dose of 10⁷ PFU/0.2 ml;
Group 6: 60 volunteers who received a single intradermal placebo dose of 0.2 ml.

State Budgetary Health Institution of the Novosibirsk Region "Municipal Infectious Disease Clinical Hospital No. 1" - 32 volunteers randomized into two groups:

Group 7: 16 volunteers who received a single intradermal VAC∆6 dose of 10⁷ PFU/0.2 ml;
Group 8: 16 volunteers who received a single intradermal placebo dose of 0.2 ml.
Before applying for a state license to the Ministry of the Russian Federation on May 4, 2022, the VACΔ6 vaccine was renamed to OrthopoxVac.

Conditions: Smallpox, Monkeypox, Cowpox, Vaccinia Virus Infection
Being tested: VAC∆6 vaccine (10⁷ PFU), VAC∆6 vaccine (10⁶ PFU), Live Smallpox Vaccine, Placebo (Sodium chloride bufus, 0.9%)
Keywords: VAC∆6 vaccine, Оrthopoxviruses, Smallpox, Сlinical study
Medical subject headings: Smallpox, Mpox, Monkeypox, Cowpox

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

VAC∆6 vaccine (10⁷ PFU)Biological
Live cell-based vaccine against smallpox and other orthopoxvirus infections (VAC∆6 vaccine) based on vaccinia virus (manufactured by FBRI SRC VB "Vector", Rospotrebnadzor).
Batch: 08-10.19 (expiry date: 13.10.2021). Dosage: single intradermal dose of 10⁷ PFU/0.2 ml of vaccinia virus.
VAC∆6 vaccine (10⁶ PFU)Biological
Live cell-based vaccine against smallpox and other orthopoxvirus infections (VAC∆6 vaccine) based on vaccinia virus (manufactured by FBRI SRC VB "Vector", Rospotrebnadzor).
Batch: 08-10.19 (expiry date: 13.10.2021). Dosage: two intradermal doses of 10⁶ PFU/0.2 ml of vaccinia virus (given 28 days apart).
Live Smallpox VaccineBiological
Live smallpox vaccine (Smallpox vaccine) (manufactured by the Federal State Unitary Enterprise NPO Microgen of the Ministry of Health of Russia).
Batch No. Т30 (expiry date: March, 2021). Dosage: Single 1x10⁶ PFU dose administered by multiple-pricking technique on the 30th/60th day after full series of vaccination with VAC∆6.
Placebo (Sodium chloride bufus, 0.9%)Other
Sodium chloride bufus, a 0.9% solvent for the preparation of a dosage form for injections (manufactured by JSC Pharmaceutical manufacturing company "Obnovlenie", Russia).
Batch: 391219 (expiry date: January, 2025).

Study groups in NCT05846243
Study group	Role	What they receive
Group 1 (The first stage): VAC∆6 (10⁷ PFU), Live Smallpox Vaccine (2 months after the vaccination)	Experimental	15 volunteers aged 18 to 60 who met the inclusion criteria and who received a single intradermal VAC∆6 dose of 1x10⁷ PFU/0.2ml. Live smallpox vaccine was administered by scarification 2 months after the vaccination. (The first stage is an open comparative study of the safety, reactogenicity, immunological activity and protective efficacy of VAC∆6 vaccine in two parallel groups). Receives: Biological: VAC∆6 vaccine (10⁷ PFU); Biological: Live Smallpox Vaccine
Group 2 (The first stage): VAC∆6 (10⁶ PFU), Live Smallpox Vaccine (1 month after the vaccination)	Experimental	15 volunteers aged 18 to 60 who met the inclusion criteria and who received two intradermal VAC∆6 doses of 10⁶ PFU/0.2ml (given 28 days apart). Live smallpox vaccine was administered by scarification one month after the full vaccination series. (The first stage is an open comparative study of the safety, reactogenicity, immunological activity and protective efficacy of VAC∆6 vaccine in two parallel groups). Receives: Biological: VAC∆6 vaccine (10⁶ PFU); Biological: Live Smallpox Vaccine
Group 3 (The second stage): two intradermal VAC∆6 (10⁶ PFU/0.2 ml) given 28 days apart.	Experimental	76 volunteers aged 18 to 60 who met the inclusion criteria and who received two intradermal VAC∆6 doses of 10⁶ PFU/0.2 ml (given 28 days apart). (The second stage is a Double-blind, Comparative, Randomized, Placebo-controlled study on Immunogenicity, Reactogenicity, and Safety of the VAC∆6 Vaccine in Parallel Groups). Receives: Biological: VAC∆6 vaccine (10⁶ PFU)
Group 4 (The second stage): two intradermal placebo doses of 0.2 ml (given 28 days apart).	Placebo comparator	76 volunteers aged 18 to 60 who met the inclusion criteria and who received two intradermal placebo doses of 0.2 ml (given 28 days apart). (The second stage is a Double-blind, Comparative, Randomized, Placebo-controlled study on Immunogenicity, Reactogenicity, and Safety of the VAC∆6 Vaccine in Parallel Groups). Receives: Other: Placebo (Sodium chloride bufus, 0.9%)
Group 5 (The second stage) in the FGBUZ MSCH-163: a single intradermal VAC∆6 (10⁷ PFU/0.2 ml).	Experimental	60 volunteers aged 18 to 60 who met the inclusion criteria and who received a single intradermal VAC∆6 dose of 10⁷ PFU/0.2 ml. (The second stage is a Double-blind, Comparative, Randomized, Placebo-controlled study on Immunogenicity, Reactogenicity, and Safety of the VAC∆6 Vaccine in Parallel Groups). Receives: Biological: VAC∆6 vaccine (10⁷ PFU)
Group 6 (The second stage) in the FGBUZ MSCH-163: a single intradermal placebo dose of 0.2 ml.	Placebo comparator	60 volunteers aged 18 to 60 who met the inclusion criteria and who received a single intradermal placebo dose of 0.2 ml. (The second stage is a Double-blind, Comparative, Randomized, Placebo-controlled study on Immunogenicity, Reactogenicity, and Safety of the VAC∆6 Vaccine in Parallel Groups). Receives: Other: Placebo (Sodium chloride bufus, 0.9%)
Group 7 (The second stage) in the Hospital No. 1: a single intradermal VAC∆6 (10⁷ PFU/0.2 ml).	Experimental	16 volunteers aged 18 to 60 who met the inclusion criteria and who received a single intradermal VAC∆6 dose of 10⁷ PFU/0.2 ml. (The second stage is a Double-blind, Comparative, Randomized, Placebo-controlled study on Immunogenicity, Reactogenicity, and Safety of the VAC∆6 Vaccine in Parallel Groups). Receives: Biological: VAC∆6 vaccine (10⁷ PFU)
Group 8 (The second stage): in the Hospital No. 1: a single intradermal placebo dose of 0.2 ml.	Placebo comparator	16 volunteers aged 18 to 60 who met the inclusion criteria and who received a single intradermal placebo dose of 0.2 ml. (The second stage is a Double-blind, Comparative, Randomized, Placebo-controlled study on Immunogenicity, Reactogenicity, and Safety of the VAC∆6 Vaccine in Parallel Groups). Receives: Other: Placebo (Sodium chloride bufus, 0.9%)

What is being measured

The primary outcome is the main question the study is designed to answer.

Changes in the percentage of vaccinees with a titer of virus-neutralizing antibodies to vaccinia virus ≥1:40, at specified time intervals.
On control days, the percentage of the vaccinees with a titer of virus-neutralizing antibodies to vaccinia virus ≥1:40 is recorded in the neutralization test in embryonated chicken eggs.
Value changes of this indicator between time points are assessed.
Measured: Group 1: at days 1, 30, 60, 89. Groups 2, 3, 4: at days 1, 28, 57, 87, 117. Groups 5, 6, 7, 8: at days 1, 30, 60, 90.

Secondary outcomes (7)

Change in antibody titers.
Determination of antibody titers to poxviruses using ELISA.
Measured: Group 1: at days 0, 1, 30, 60, 89. Groups 2, 3, 4: at days 0, 1, 28, 57, 87, 117. Groups 5, 6, 7, 8: at days 0, 1, 30, 60, 90.
Determination of the lymphocyte migration index (MI)
Determination of the lymphocyte migration index (MI) is carried out in order to conduct a subsequent assessment of the activity of specific DTH effectors in vitro. The MI is calculated by the formula: MI=A/B, where A is the number of cells in the control wells, B is the number of cells in the experimental wells with an inhibitory dose.
On control days, the changes in the activity of DTH effectors in vitro is assessed. The assessment of the activity of specific DTH effectors in vitro is carried out according to the MI, which characterizes the migration activity of leukocytes; according to the index of inhibition of migration (MII), which characterizes the intensity of production of lymphokines, and according to the integral indicator of the effector functions (IEF). These MI, MII and IEF for each vaccinated person are compared with the corresponding normal parameters. The reaction is considered positive if the difference between the experimental and control values exceeds 20%.
Measured: Group 1: at days 30, 89. Groups 2, 3, 4: at days 1, 28, 57, 117. Groups 5, 6, 7, 8: at days 1, 30, 90.
Determination of the lymphocyte migration inhibition index (MII)
Determination of the lymphocyte migration inhibition index (MII) is carried out in order to conduct a subsequent assessment of the activity of specific DTH effectors in vitro. The MII is calculated by the formula: MII=B/А, where A is the number of cells in the control wells, B is the number of cells in the experimental wells with an inhibitory dose.
On control days, the changes in the activity of DTH effectors in vitro is assessed. The assessment of the activity of specific DTH effectors in vitro is carried out according to the migration index (MI), which characterizes the migration activity of leukocytes; according to the MII, which characterizes the intensity of production of lymphokines, and according to the integral indicator of the effector functions (IEF). These MI, MII and IEF for each vaccinated person are compared with the corresponding normal parameters. The reaction is considered positive if the difference between the experimental and control values exceeds 20%.
Measured: Group 1: at days 30, 89. Groups 2, 3, 4: at days 1, 28, 57, 117. Groups 5, 6, 7, 8: at days 1, 30, 90.
Determination of the integral indicator of the effector functions (IEF)
Determination of the integral indicator of the effector functions (IEF) is carried out in order to conduct a subsequent assessment of the activity of specific DTH effectors in vitro. The IEF is calculated by the formula: IEF=С/B, where C is the number of lymphocytes in the test wells with the stimulation dose and B is the number of lymphocytes in the test wells with the inhibitory dose.
On control days, the changes in the activity of DTH effectors in vitro in each vaccinated person is assessed. The assessment of the activity of specific DTH effectors is carried out according to the migration index (MI), which characterizes the migration activity of leukocytes; according to the index of inhibition of migration (MII), and according to the IEF. These MI, MII and IEF for each vaccinated person are compared with the corresponding normal parameters. The reaction is considered positive if the difference between the experimental and control values exceeds 20%.
Measured: Group 1: at days 30, 89. Groups 2, 3, 4: at days 1, 28, 57, 117. Groups 5, 6, 7, 8: at days 1, 30, 90.
Recording the number of local reactions.
On control days, the sum of local reactions is recorded: formation of inoculation elements (redness, swelling and papulo-nodules, pustules, vesicles, erythema, induration). Value changes of this indicator between time points are assessed.
Evaluation criteria for local reactions:
1. The intensity or severity of adverse reactions should be assessed on a 4-point scale: 0 - none (no symptoms); 1 - mild (presence of mild symptoms); 2 - medium (symptoms that noticeably impair normal daily activities); 3 - severe (symptoms that interfere with normal daily activities).
2. The severity of local reactions was assessed according to the following criteria:
- Hyperemia < 50.0 mm (⌀) or an infiltrate < 25.0 mm (⌀) - weak;
- Hyperemia ≤ 50.0 mm (⌀) or an infiltrate 26.0-50.0 mm (⌀) - medium;
- Infiltrate > 50.0 mm (⌀) - strong.
Measured: Group 1: at days 1-14, 21, 30, 60-74, 80, 89. Group 2: at days 1-14, 21, 28-41, 48, 57, 87-100, 107, 116. Groups 3, 4: at days 1-14, 21, 28-41, 48, 57, 87, 117. Groups 5, 6, 7, 8: at days 1-14, 21, 30.
Recording the number of systemic reactions.
Recording the number of systemic reactions (malaise, headache, rise in body temperature, weakness, sweating, sleep and appetite disorders, nausea, vomiting, abdominal pain, etc.). Evaluating criteria for systemic reactions:
1. The intensity or severity of adverse reactions should be assessed on a 4-point scale: 0 - none (no symptoms); 1 - mild (presence of mild symptoms); 2 - medium (symptoms that noticeably impair normal daily activities); 3 - severe (symptoms that interfere with normal daily activities).
2. The temperature response should be evaluated according to the following categories in °С: 0 (none) ≤ 37 °C; 1 (weak) > 37 °С - ≤ 37.5 °С; 2 (medium) > 37.5 °С - ≤ 38.5 °С; 3 (strong) > 38.5°C.
Measured: Group 1: at days 1-14, 21, 30, 60-74, 80, 89. Group 2: at days 1-14, 21, 28-41, 48, 57, 87-100, 107, 116. Groups 3, 4: at days 1-14, 21, 28-41, 48, 57, 87, 117. Groups 5, 6, 7, 8: at days 1-14, 21, 30.
Recording of the percentage of the vaccinated with various degrees of manifestation of systemic and local reactions.
Recording of the percentage of the vaccinated with various degrees of manifestation of systemic and local reactions.
Measured: Group 1: at days 1-14, 21, 30, 60-74, 80, 89. Group 2: at days 1-14, 21, 28-41, 48, 57, 87-100, 107, 116. Groups 3, 4: at days 1-14, 21, 28-41, 48, 57, 87, 117. Groups 5, 6, 7, 8: at days 1-14, 21, 30.

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

1 Oct 20211 Apr 2022

First posted6 May 2023
Study start1 Oct 2021
Primary completion31 Dec 2021
Study completion1 Apr 2022

Resources

Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
Publications (11)Papers the sponsor has linked to this study.
Other trials for SmallpoxStudies of the same condition, open and under way.
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 2/3
Primary purpose: Prevention
Allocation: Randomised
Intervention model: Parallel groups
Model description: This was a clinical study of VAC∆6 vaccine designed to induce specific immunity to human-pathogenic orthopoxviruses (VARV, MPXV, CPXV, VACV)
Masking: Double blind
Who is masked: Participant, Investigator
Enrolment: 334 participants (actual)

IDs, dates and publications

ClinicalTrials.gov ID: NCT05846243
Sponsor's protocol ID: VAC∆6-01/20
Status last verified: Mar 2023
First submitted: 23 Mar 2023
Last updated: 6 May 2023
Results posted: No
Data monitoring committee: No
FDA-regulated drug: No
FDA-regulated device: No
Individual data sharing: No

Publications

Yakubitskiy SN, Kolosova IV, Maksyutov RA, Shchelkunov SN. Attenuation of Vaccinia Virus. Acta Naturae. 2015 Oct-Dec;7(4):113-21.
PubMed 26798498
Maksyutov RA, Yakubitskyi SN, Kolosova IV, Shchelkunov SN. Comparing New-Generation Candidate Vaccines against Human Orthopoxvirus Infections. Acta Naturae. 2017 Apr-Jun;9(2):88-93.
PubMed 28740731
Olson VA, Shchelkunov SN. Are We Prepared in Case of a Possible Smallpox-Like Disease Emergence? Viruses. 2017 Aug 27;9(9):242. doi: 10.3390/v9090242.
PubMed 32962316
Shchelkunova GA, Shchelkunov SN. Smallpox, Monkeypox and Other Human Orthopoxvirus Infections. Viruses. 2022 Dec 29;15(1):103. doi: 10.3390/v15010103.
PubMed 36680142
Shchelkunova GA, Shchelkunov SN. 40 Years without Smallpox. Acta Naturae. 2017 Oct-Dec;9(4):4-12.
PubMed 29340212
Shchelkunov SN, Shchelkunova GA. Genes that Control Vaccinia Virus Immunogenicity. Acta Naturae. 2020 Jan-Mar;12(1):33-41. doi: 10.32607/actanaturae.10935.
PubMed 32477596
Shchelkunov SN, Shchelkunova GA. [We should be prepared to smallpox re-emergence.]. Vopr Virusol. 2019;64(5):206-214. doi: 10.36233/0507-4088-2019-64-5-206-214. Russian.
PubMed 32167685
Maksyutov RA, Yakubitskiy SN, Kolosova IV, Tregubchak TV, Shvalov AN, Gavrilova EV, Shchelkunov SN. Genome stability of the vaccine strain VACDelta6. Vavilovskii Zhurnal Genet Selektsii. 2022 Jul;26(4):394-401. doi: 10.18699/VJGB-22-48.
PubMed 35903306
Marennikova S.S., Shchelkunov S.N. Orthopoxviruses pathogenic for humans (monograph) // KMK Scientific Press Ltd., M. - 1998, - 386 p (in Russian).
Kolosova I.V., Babkina I.N., Yakubitsky S.N., Maksyutov R.A., Safronov P.F., Shchelkunov S.N. Recombinant strain L-IVP 1421ABJCN of vaccinia virus with deleted virulence genes A56R, B8R, J2R, C3L, N1L to obtain a live cell-based attenuated vaccine against smallpox and other orthopoxviruses pathogenic to humans // RF Patent No. 2588388, priority 20.04.2015 (in Russian).
Yakubitsky S.N., Kolosova I.V., Maksyutov R.A., Shchelkunov S.N. Recombinant strain VACΔ6 of vaccinia virus with deleted virulence genes C3L, N1L, J2R, A35R, A56R, B8R for obtaining a live cell-based attenuated vaccine against smallpox and other human orthopoxvirus infections // RF Patent No. 2621868, priority 24.06.2016 (in Russian).

Want to know more?

The sponsor has not listed a contact. The official record may have more details.

Talk to your doctor first and take this page with you. Only the study team can confirm whether you can join.

Questions to ask the study team

What is the study trying to find out?
What would I need to do, and how often would I visit?
Could I receive a placebo instead of the treatment?
What are the possible risks and benefits for me?
Will it cost me anything? Are travel or time paid for?
Can I keep seeing my own doctor during the study?
What happens when the study ends?

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Study at a glance

From the registry record, last updated by the sponsor on 6 May 2023. Recruitment status is as the sponsor reported it: confirm with the study team.

Official title: Double-blind, Comparative, Randomized, Placebo-controlled Study on Immunogenicity, Reactogenicity and Safety of Live Cell-based Vaccine Against Smallpox and Other Orthopoxvirus Infections (VACΔ6 Vaccine) in Volunteers Aged 18-60 Years
ClinicalTrials.gov ID: NCT05846243
Acronym / sponsor ID: VAC∆6-01/20
Conditions: Smallpox, Monkeypox, Cowpox, Vaccinia Virus Infection
Keywords: VAC∆6 vaccine, Оrthopoxviruses, Smallpox, Сlinical study
Phase: Phase 2/3
Study type: Interventional
Recruitment status: Completed
Enrolment: 334 participants (actual)
Lead sponsor: Federal Budgetary Research Institution State Research Center of Virology and Biotechnology "Vector"Other government
Study start: 1 Oct 2021 (actual)
Primary completion: 31 Dec 2021 (actual)
Study completion: 1 Apr 2022 (actual)
First posted: 6 May 2023 (actual)
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 Aim:

The research tasks are to:

To study the immunological activity of a single VAC∆6 vaccine dose of 1x10⁷ plaque-forming units (PFU).
To study the immunological activity of two VAC∆6 vaccine doses (given 28 days apart) of 1x10⁶ PFU.
Assess the safety of different VAC∆6 vaccination schedules using a set of clinical and laboratory-instrumental techniques (thermometry, measurement of blood pressure, heart and lung auscultation, ECG, common blood and urine tests, biochemical, immunological and virological studies).
Assess the reactogenicity of different VAC∆6 vaccination schedules (number of local and systemic reactions, the percentage of those vaccinated with systemic and local reactions of various severity degrees).
To identify VAC∆6 vaccine-associated adverse events.
Study cell-mediated immunity induced by different VAC∆6 vaccination schedules.
Determine the presence of the virus in specific skin formations (crusts, pustules), saliva, blood and urine.
Evaluate the protective efficacy of one and two doses of the studied VAC∆6 vaccine.

Detailed description

The study included 334 healthy volunteers of both sexes aged 18-60 years who met the inclusion criteria and had no exclusion criteria.

The study was carried out in two stages:

Group 1: 15 volunteers who received a single intradermal VAC∆6 dose of 1x10⁷ PFU. Live smallpox vaccine was administered by scarification 2 months after the vaccination.
Group 2: 15 volunteers who received two intradermal VAC∆6 doses of 1x10⁶ PFU (given 28 days apart). Live smallpox vaccine was administered by scarification one month after the full vaccination series.

FGBUZ MSCH-163, FMBA Russia - 272 volunteers randomized into four groups:

Group 3: 76 volunteers who received two intradermal VAC∆6 doses of 10⁶ PFU/0.2 ml (given 28 days apart);
Group 4: 76 volunteers who received two intradermal placebo doses of 0.2 ml (given 28 days apart);
Group 5: 60 volunteers who received a single intradermal VAC∆6 dose of 10⁷ PFU/0.2 ml;
Group 6: 60 volunteers who received a single intradermal placebo dose of 0.2 ml.

State Budgetary Health Institution of the Novosibirsk Region "Municipal Infectious Disease Clinical Hospital No. 1" - 32 volunteers randomized into two groups:

Group 7: 16 volunteers who received a single intradermal VAC∆6 dose of 10⁷ PFU/0.2 ml;
Group 8: 16 volunteers who received a single intradermal placebo dose of 0.2 ml.
Before applying for a state license to the Ministry of the Russian Federation on May 4, 2022, the VACΔ6 vaccine was renamed to OrthopoxVac.

Study design

Primary purpose: Prevention
Allocation: Randomised
Intervention model: Parallel groups
Masking: Double blind (participant, investigator)
Number of arms: 8
Model description: This was a clinical study of VAC∆6 vaccine designed to induce specific immunity to human-pathogenic orthopoxviruses (VARV, MPXV, CPXV, VACV)

Arm	Type	Receives
Group 1 (The first stage): VAC∆6 (10⁷ PFU), Live Smallpox Vaccine (2 months after the vaccination)	Experimental	Biological: VAC∆6 vaccine (10⁷ PFU), Biological: Live Smallpox Vaccine15 volunteers aged 18 to 60 who met the inclusion criteria and who received a single intradermal VAC∆6 dose of 1x10⁷ PFU/0.2ml. Live smallpox vaccine was administered by scarification 2 months after the vaccination. (The first stage is an open comparative study of the safety, reactogenicity, immunological activity and protective efficacy of VAC∆6 vaccine in two parallel groups).
Group 2 (The first stage): VAC∆6 (10⁶ PFU), Live Smallpox Vaccine (1 month after the vaccination)	Experimental	Biological: VAC∆6 vaccine (10⁶ PFU), Biological: Live Smallpox Vaccine15 volunteers aged 18 to 60 who met the inclusion criteria and who received two intradermal VAC∆6 doses of 10⁶ PFU/0.2ml (given 28 days apart). Live smallpox vaccine was administered by scarification one month after the full vaccination series. (The first stage is an open comparative study of the safety, reactogenicity, immunological activity and protective efficacy of VAC∆6 vaccine in two parallel groups).
Group 3 (The second stage): two intradermal VAC∆6 (10⁶ PFU/0.2 ml) given 28 days apart.	Experimental	Biological: VAC∆6 vaccine (10⁶ PFU)76 volunteers aged 18 to 60 who met the inclusion criteria and who received two intradermal VAC∆6 doses of 10⁶ PFU/0.2 ml (given 28 days apart). (The second stage is a Double-blind, Comparative, Randomized, Placebo-controlled study on Immunogenicity, Reactogenicity, and Safety of the VAC∆6 Vaccine in Parallel Groups).
Group 4 (The second stage): two intradermal placebo doses of 0.2 ml (given 28 days apart).	Placebo comparator	Other: Placebo (Sodium chloride bufus, 0.9%)76 volunteers aged 18 to 60 who met the inclusion criteria and who received two intradermal placebo doses of 0.2 ml (given 28 days apart). (The second stage is a Double-blind, Comparative, Randomized, Placebo-controlled study on Immunogenicity, Reactogenicity, and Safety of the VAC∆6 Vaccine in Parallel Groups).
Group 5 (The second stage) in the FGBUZ MSCH-163: a single intradermal VAC∆6 (10⁷ PFU/0.2 ml).	Experimental	Biological: VAC∆6 vaccine (10⁷ PFU)60 volunteers aged 18 to 60 who met the inclusion criteria and who received a single intradermal VAC∆6 dose of 10⁷ PFU/0.2 ml. (The second stage is a Double-blind, Comparative, Randomized, Placebo-controlled study on Immunogenicity, Reactogenicity, and Safety of the VAC∆6 Vaccine in Parallel Groups).
Group 6 (The second stage) in the FGBUZ MSCH-163: a single intradermal placebo dose of 0.2 ml.	Placebo comparator	Other: Placebo (Sodium chloride bufus, 0.9%)60 volunteers aged 18 to 60 who met the inclusion criteria and who received a single intradermal placebo dose of 0.2 ml. (The second stage is a Double-blind, Comparative, Randomized, Placebo-controlled study on Immunogenicity, Reactogenicity, and Safety of the VAC∆6 Vaccine in Parallel Groups).
Group 7 (The second stage) in the Hospital No. 1: a single intradermal VAC∆6 (10⁷ PFU/0.2 ml).	Experimental	Biological: VAC∆6 vaccine (10⁷ PFU)16 volunteers aged 18 to 60 who met the inclusion criteria and who received a single intradermal VAC∆6 dose of 10⁷ PFU/0.2 ml. (The second stage is a Double-blind, Comparative, Randomized, Placebo-controlled study on Immunogenicity, Reactogenicity, and Safety of the VAC∆6 Vaccine in Parallel Groups).
Group 8 (The second stage): in the Hospital No. 1: a single intradermal placebo dose of 0.2 ml.	Placebo comparator	Other: Placebo (Sodium chloride bufus, 0.9%)16 volunteers aged 18 to 60 who met the inclusion criteria and who received a single intradermal placebo dose of 0.2 ml. (The second stage is a Double-blind, Comparative, Randomized, Placebo-controlled study on Immunogenicity, Reactogenicity, and Safety of the VAC∆6 Vaccine in Parallel Groups).

Who may qualify

Ages: 18 to 60 years
Sex: All
Healthy volunteers: Accepted
Age groups: Adult

Key inclusion criteria (6 listed)

Signed and dated informed consent of a volunteer to participate in a clinical trial obtained prior to any of the study procedures.
A verified diagnosis of "healthy" according to standard clinical, laboratory and instrumental methods of examination.
Age from 18 to 60 inclusive.
Body mass index from 18.5 to 30 kg/m3.
Ability to attend all scheduled visits and all scheduled procedures and examinations.

Key exclusion criteria (34 listed)

Hypersensitivity to any component of the product, allergy to vaccine components.
Pregnancy or breastfeeding.
The military.
Persons in custody in detention facilities and those serving sentences in correctional facilities.
Children under 18.

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
VAC∆6 vaccine (10⁷ PFU)Live cell-based vaccine against smallpox and other orthopoxvirus infections (VAC∆6 vaccine) based on vaccinia virus (manufactured by FBRI SRC VB "Vector", Rospotrebnadzor). Batch: 08-10.19 (expiry date: 13.10.2021). Dosage: single intradermal dose of 10⁷ PFU/0.2 ml of vaccinia virus.	Biological	Group 1 (The first stage): VAC∆6 (10⁷ PFU), Live Smallpox Vaccine (2 months after the vaccination), Group 5 (The second stage) in the FGBUZ MSCH-163: a single intradermal VAC∆6 (10⁷ PFU/0.2 ml)., Group 7 (The second stage) in the Hospital No. 1: a single intradermal VAC∆6 (10⁷ PFU/0.2 ml).
VAC∆6 vaccine (10⁶ PFU)Live cell-based vaccine against smallpox and other orthopoxvirus infections (VAC∆6 vaccine) based on vaccinia virus (manufactured by FBRI SRC VB "Vector", Rospotrebnadzor). Batch: 08-10.19 (expiry date: 13.10.2021). Dosage: two intradermal doses of 10⁶ PFU/0.2 ml of vaccinia virus (given 28 days apart).	Biological	Group 2 (The first stage): VAC∆6 (10⁶ PFU), Live Smallpox Vaccine (1 month after the vaccination), Group 3 (The second stage): two intradermal VAC∆6 (10⁶ PFU/0.2 ml) given 28 days apart.
Live Smallpox VaccineLive smallpox vaccine (Smallpox vaccine) (manufactured by the Federal State Unitary Enterprise NPO Microgen of the Ministry of Health of Russia). Batch No. Т30 (expiry date: March, 2021). Dosage: Single 1x10⁶ PFU dose administered by multiple-pricking technique on the 30th/60th day after full series of vaccination with VAC∆6.	Biological	Group 1 (The first stage): VAC∆6 (10⁷ PFU), Live Smallpox Vaccine (2 months after the vaccination), Group 2 (The first stage): VAC∆6 (10⁶ PFU), Live Smallpox Vaccine (1 month after the vaccination)
Placebo (Sodium chloride bufus, 0.9%)Sodium chloride bufus, a 0.9% solvent for the preparation of a dosage form for injections (manufactured by JSC Pharmaceutical manufacturing company "Obnovlenie", Russia). Batch: 391219 (expiry date: January, 2025).	Other	Group 4 (The second stage): two intradermal placebo doses of 0.2 ml (given 28 days apart)., Group 6 (The second stage) in the FGBUZ MSCH-163: a single intradermal placebo dose of 0.2 ml., Group 8 (The second stage): in the Hospital No. 1: a single intradermal placebo dose of 0.2 ml.

Primary outcome

Changes in the percentage of vaccinees with a titer of virus-neutralizing antibodies to vaccinia virus ≥1:40, at specified time intervals.
Time frame: Group 1: at days 1, 30, 60, 89. Groups 2, 3, 4: at days 1, 28, 57, 87, 117. Groups 5, 6, 7, 8: at days 1, 30, 60, 90.
On control days, the percentage of the vaccinees with a titer of virus-neutralizing antibodies to vaccinia virus ≥1:40 is recorded in the neutralization test in embryonated chicken eggs. Value changes of this indicator between time points are assessed.

7 secondary outcomes

Change in antibody titers.
Time frame: Group 1: at days 0, 1, 30, 60, 89. Groups 2, 3, 4: at days 0, 1, 28, 57, 87, 117. Groups 5, 6, 7, 8: at days 0, 1, 30, 60, 90.
Determination of the lymphocyte migration index (MI)
Time frame: Group 1: at days 30, 89. Groups 2, 3, 4: at days 1, 28, 57, 117. Groups 5, 6, 7, 8: at days 1, 30, 90.
Determination of the lymphocyte migration inhibition index (MII)
Time frame: Group 1: at days 30, 89. Groups 2, 3, 4: at days 1, 28, 57, 117. Groups 5, 6, 7, 8: at days 1, 30, 90.
Determination of the integral indicator of the effector functions (IEF)
Time frame: Group 1: at days 30, 89. Groups 2, 3, 4: at days 1, 28, 57, 117. Groups 5, 6, 7, 8: at days 1, 30, 90.
Recording the number of local reactions.
Time frame: Group 1: at days 1-14, 21, 30, 60-74, 80, 89. Group 2: at days 1-14, 21, 28-41, 48, 57, 87-100, 107, 116. Groups 3, 4: at days 1-14, 21, 28-41, 48, 57, 87, 117. Groups 5, 6, 7, 8: at days 1-14, 21, 30.
Recording the number of systemic reactions.
Time frame: Group 1: at days 1-14, 21, 30, 60-74, 80, 89. Group 2: at days 1-14, 21, 28-41, 48, 57, 87-100, 107, 116. Groups 3, 4: at days 1-14, 21, 28-41, 48, 57, 87, 117. Groups 5, 6, 7, 8: at days 1-14, 21, 30.
Recording of the percentage of the vaccinated with various degrees of manifestation of systemic and local reactions.
Time frame: Group 1: at days 1-14, 21, 30, 60-74, 80, 89. Group 2: at days 1-14, 21, 28-41, 48, 57, 87-100, 107, 116. Groups 3, 4: at days 1-14, 21, 28-41, 48, 57, 87, 117. Groups 5, 6, 7, 8: at days 1-14, 21, 30.

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 6 May 2023.
Background: PubMed 26798498Yakubitskiy SN, Kolosova IV, Maksyutov RA, Shchelkunov SN. Attenuation of Vaccinia Virus. Acta Naturae. 2015 Oct-Dec;7(4):113-21.
Background: PubMed 28740731Maksyutov RA, Yakubitskyi SN, Kolosova IV, Shchelkunov SN. Comparing New-Generation Candidate Vaccines against Human Orthopoxvirus Infections. Acta Naturae. 2017 Apr-Jun;9(2):88-93.
Background: PubMed 32962316Olson VA, Shchelkunov SN. Are We Prepared in Case of a Possible Smallpox-Like Disease Emergence? Viruses. 2017 Aug 27;9(9):242. doi: 10.3390/v9090242.
Background: PubMed 36680142Shchelkunova GA, Shchelkunov SN. Smallpox, Monkeypox and Other Human Orthopoxvirus Infections. Viruses. 2022 Dec 29;15(1):103. doi: 10.3390/v15010103.
Background: PubMed 29340212Shchelkunova GA, Shchelkunov SN. 40 Years without Smallpox. Acta Naturae. 2017 Oct-Dec;9(4):4-12.
Background: PubMed 32477596Shchelkunov SN, Shchelkunova GA. Genes that Control Vaccinia Virus Immunogenicity. Acta Naturae. 2020 Jan-Mar;12(1):33-41. doi: 10.32607/actanaturae.10935.
Background: PubMed 32167685Shchelkunov SN, Shchelkunova GA. [We should be prepared to smallpox re-emergence.]. Vopr Virusol. 2019;64(5):206-214. doi: 10.36233/0507-4088-2019-64-5-206-214. Russian.
Background: PubMed 35903306Maksyutov RA, Yakubitskiy SN, Kolosova IV, Tregubchak TV, Shvalov AN, Gavrilova EV, Shchelkunov SN. Genome stability of the vaccine strain VACDelta6. Vavilovskii Zhurnal Genet Selektsii. 2022 Jul;26(4):394-401. doi: 10.18699/VJGB-22-48.
BackgroundMarennikova S.S., Shchelkunov S.N. Orthopoxviruses pathogenic for humans (monograph) // KMK Scientific Press Ltd., M. - 1998, - 386 p (in Russian).
BackgroundKolosova I.V., Babkina I.N., Yakubitsky S.N., Maksyutov R.A., Safronov P.F., Shchelkunov S.N. Recombinant strain L-IVP 1421ABJCN of vaccinia virus with deleted virulence genes A56R, B8R, J2R, C3L, N1L to obtain a live cell-based attenuated vaccine against smallpox and other orthopoxviruses pathogenic to humans // RF Patent No. 2588388, priority 20.04.2015 (in Russian).
BackgroundYakubitsky S.N., Kolosova I.V., Maksyutov R.A., Shchelkunov S.N. Recombinant strain VACΔ6 of vaccinia virus with deleted virulence genes C3L, N1L, J2R, A35R, A56R, B8R for obtaining a live cell-based attenuated vaccine against smallpox and other human orthopoxvirus infections // RF Patent No. 2621868, priority 24.06.2016 (in Russian).
Individual participant dataSharing planned: No

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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.

Vladimir I. Kuzubov, PhD principal investigator

Medical and Sanitary Unit No. 163 (FGBUZ MSCH-163, FMBA Russia) (Novosibirsk)

Irina V Krasil'nikova, PhD principal investigator

Municipal Infectious Disease Clinical Hospital No. 1 (Novosibirsk)

2 sites in 1 country: see every site and its status.

Questions about this trial

What is this clinical trial studying?

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 6 inclusion and 34 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 6 May 2023. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 2 sites in Russia. 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 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.

Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.

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?

Changes in the percentage of vaccinees with a titer of virus-neutralizing antibodies to vaccinia virus ≥1:40, at specified time intervals. (time frame: Group 1: at days 1, 30, 60, 89. Groups 2, 3, 4: at days 1, 28, 57, 87, 117. Groups 5, 6, 7, 8: at days 1, 30, 60, 90.). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT05846243, which also lists 11 linked publications.

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 6 May 2023.