Investigational Vaccine for Chickenpox

Recruiting at 38 trial locations

Overseen By EU GSK Clinical Trials Call Center

Age: < 18

Sex: Any

Trial Phase: Phase 3

Sponsor: GlaxoSmithKline

Must not be taking: Immune-modifying drugs, Corticosteroids

Disqualifiers: Immunosuppressive conditions, Neurological disorders, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Pivotal Trial (Near Approval) This treatment is in the last trial phase before FDA approval

Prior Safety Data This treatment has passed at least one previous human trial

Compensation: Varies

Number of Visits: 1

Duration: 1 day

750 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial tests the effectiveness of a new chickenpox vaccine compared to an approved one. It targets healthy children aged 12 to 15 months who have never had chickenpox or its vaccine. The trial aims to determine if the new vaccine is safe and well-tolerated. Children who have not received vaccines for chickenpox, measles, mumps, rubella, or hepatitis A, but have completed their initial pneumonia vaccine series, might be suitable candidates. As a Phase 3 trial, this study represents the final step before FDA approval, allowing participants to contribute to significant vaccine advancements.

Will I have to stop taking my current medications?

The trial does not specify if you need to stop taking current medications, but it does exclude participants using certain immune-modifying drugs or investigational products within specific time frames before the study. It's best to discuss your current medications with the study team to see if they affect your eligibility.

Is there any evidence suggesting that this treatment is likely to be safe for humans?

Research has shown that the new chickenpox vaccine is generally safe. Most side effects observed in earlier studies were mild or moderate and occurred soon after vaccination. This aligns with results from other studies. Additionally, a study involving children with juvenile idiopathic arthritis (JIA) found the vaccine to be safe and effective for them.

Although this new vaccine is still being compared to an already approved one, results so far suggest it is well-tolerated by people. ^{1 2 3 4 5}

Why do researchers think this study treatment might be promising?

The investigational varicella vaccine (VNS) is unique because it potentially offers a broader immune response by combining a new varicella vaccine with other standard vaccines like MMR and HAV, plus a pneumococcal conjugate vaccine (PCV). Unlike current chickenpox vaccines, which typically focus solely on varicella-zoster virus, this approach integrates multiple vaccinations, which might streamline immunization schedules for children. Researchers are excited about this treatment as it could enhance protection against several infections simultaneously, potentially improving overall vaccination compliance and coverage.

What evidence suggests that this investigational varicella vaccine could be an effective treatment for chickenpox?

Research has shown that chickenpox vaccines effectively prevent the disease. One study found that a single dose of the vaccine offered moderate protection, with effectiveness between 82% and 85% for any level of the disease, and full protection against severe cases. Another study found that taking two doses increased effectiveness to 87%. In this trial, participants in the VNS Group will receive the investigational varicella vaccine, which is being tested for its potential to provide strong protection for children against chickenpox. Early data also showed that recipients of the vaccine developed good immune responses, known as seroconversion. ^{1 6 7 8 9}

Are You a Good Fit for This Trial?

This trial is for healthy children aged 12 to 15 months who have never had chickenpox or the chickenpox vaccine. They must not have received any other vaccines within four weeks before the study starts and should not be planning to receive any during the study.

Inclusion Criteria

Participant's parent(s)/Legally acceptable representatives (LAR[s]), who, in the opinion of the investigator, can and will comply with the requirements of the protocol (e.g., completion of the eDiaries, return for follow-up visits)

Written or witnessed/thumb printed informed consent obtained from the participant's parent(s)/LAR(s) prior to performance of any study-specific procedure

Healthy participants as established by medical history and clinical examination before entering the study

Exclusion Criteria

Previous vaccination against measles, mumps, and rubella

I have had chickenpox in the past.

Concurrently participating in another clinical study, at any time during the study period, in which the participant has been or will be exposed to an investigational or a non-investigational intervention (drug/invasive medical device)

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

1-2 weeks

Treatment

Participants receive 1 dose of either the investigational VNS vaccine or the marketed VV, along with MMR, HAV, and PCV vaccines on Day 1

1 day

1 visit (in-person)

Follow-up

Participants are monitored for safety and effectiveness, including reporting of systemic events and adverse events

26 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Investigational varicella vaccine

Trial Overview

The trial is testing a new investigational varicella (chickenpox) vaccine against an already approved one, Varivax. It will compare how well each vaccine works and how safe they are when given to young children.

How Is the Trial Designed?

Group I: VNS Group Experimental Treatment 6 Interventions

Participants receive 1 dose of a VNS vaccine, 1 dose of measles, mumps, and rubella (MMR) vaccine, 1 dose of hepatitis A (HAV) vaccine, and 1 dose of PCV (either PCV 13 or Vaxneuvance or PCV 20) on Day 1.

Group II: VV Group Active Control 6 Interventions

Participants receive 1 dose of a marketed VV, 1 dose of MMR vaccine, 1 dose of HAV vaccine, and 1 dose of PCV (either PCV 13 or Vaxneuvance or PCV 20) on Day 1.

Who Is Running the Clinical Trial?

GlaxoSmithKline

Lead Sponsor

Trials

4,834

Recruited

8,389,000+

Headquarters

London, UK

Known For

Vaccines & Medicines

Top Products

**Advair (salmeterol, fluticasone propionate)**, **Shingrix (shingles vaccine)**, **Augmentin (amoxicillin/clavulanate potassium)**, **Ventolin (salbutamol sulfate)

Dame Emma Walmsley

GlaxoSmithKline

Chief Executive Officer since 2017

MA in Classics and Modern Languages from Oxford University

Dr. Hal Barron

GlaxoSmithKline

Chief Medical Officer since 2018

MD from Harvard Medical School

Published Research Related to This Trial

In a study of over 1.1 million children who received the varicella vaccine, there was no significant increase in the risk of serious adverse events like idiopathic thrombocytopenic purpura (ITP), meningitis, encephalitis, or ischemic stroke following vaccination.

A slight increase in the risk of pneumonia was observed during the 6th week post-vaccination, but this was not seen for other serious conditions, indicating that the varicella vaccine is generally safe with minimal risk of severe side effects.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Assessment of pre-specified adverse events following varicella vaccine: A population-based self-controlled risk interval study. Liu, CH., Yeh, YC., Huang, WT., et al.[2021]

Varilrix, the first refrigerator-stable varicella vaccine, has been used safely and effectively in over 10,000 individuals across clinical trials and mass vaccination programs, demonstrating its immunogenicity and efficacy against chickenpox.

With 16 years of clinical and postmarketing experience, Varilrix is indicated for high-risk groups and healthy individuals, highlighting its importance in preventing varicella in various populations.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Sixteen years of global experience with the first refrigerator-stable varicella vaccine (Varilrix). Kreth, HW., Lee, BW., Kosuwon, P., et al.[2019]

The VAR-PE process for the varicella vaccine demonstrated 100% seroconversion in healthy children aged 12 to 23 months, showing that it is as effective as the commercial varicella vaccine (VAR) in inducing an immune response.

While both vaccines had similar rates of injection-site adverse events, VAR-PE was associated with higher instances of pyrexia and otitis media, indicating some differences in safety profiles, but overall, the incidence of adverse events decreased after the second dose.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A double-blind, randomized, multicenter, controlled study to evaluate the immunogenicity, safety, and tolerability of varicella vaccine (VARIVAX™) passage extension 34 (PE34) process administered concomitantly with measles, mumps, and rubella vaccine (M-M-R™ II). Silas, PE., Zissman, EN., Gardner, J., et al.[2021]

The varicella vaccine is effective in preventing chickenpox in immunocompromised children, such as those with acute leukemia or solid tumors, and also benefits healthy seronegative siblings.

Acyclovir, an antiviral drug, effectively reduces severe complications from chickenpox in at-risk groups, and the use of zoster hyperimmunoglobulin provides additional protection during the incubation period, suggesting that with these interventions, chickenpox will become less of a medical concern even for vulnerable populations.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[Results of virostatic treatment of varicella with various severity]. Stary, A.[2013]

Between 1995 and 2005, nearly 48 million doses of the varicella vaccine were distributed, with 25,306 adverse events reported, indicating a low incidence of serious adverse events at 2.6 per 100,000 doses.

While some adverse events, such as meningitis, were linked to the vaccine strain of varicella-zoster virus, serious complications remain rare and are outweighed by the significant benefits of vaccination, highlighting the importance of ongoing safety monitoring.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Safety of varicella vaccine after licensure in the United States: experience from reports to the vaccine adverse event reporting system, 1995-2005. Chaves, SS., Haber, P., Walton, K., et al.[2022]

In a trial involving 37 leukemic children, the live attenuated OKA varicella vaccine successfully fully immunized all 20 seronegative patients, demonstrating its efficacy in this vulnerable population.

The vaccine was well-tolerated with only a few side effects and no cases of generalized vaccinal infection, suggesting it is a safe option for immunocompromised patients.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Study of tolerance and effectiveness of a varicella vaccine in leukemic children. Bancillon, A., Leblanc, T., Baruchel, A., et al.[2007]

In a study of 505 healthy children aged 1 to 12 years, the thermostable varicella vaccine was found to be well tolerated, with most side effects being mild and temporary, resolving within the follow-up period.

Only two subjects experienced severe symptoms, but no serious adverse events were reported, indicating a strong safety profile for the vaccine.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Reactogenicity to a live attenuated varicella vaccine in Canadian children. Diaz-Mitoma, F., Halperin, SA., Scheifele, D.[2020]

Children who experienced breakthrough varicella after being vaccinated had significantly fewer total and vesicular lesions compared to those with natural varicella, indicating a milder form of the disease.

Breakthrough varicella was associated with a lower incidence of fever and a shorter duration of illness, suggesting that the live attenuated vaccine effectively modifies the clinical severity of chickenpox.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Clinical survey of natural varicella compared with breakthrough varicella after immunization with live attenuated Oka/Merck varicella vaccine. Bernstein, HH., Rothstein, EP., Watson, BM., et al.[2010]

The Advisory Committee on Immunization Practices (ACIP) has issued its first recommendations for the use of the live, attenuated varicella virus vaccine (VARIVAX), which is approved for healthy individuals aged 12 months and older.

These recommendations also update previous guidelines on the use of varicella zoster immune globulin (VZIG) for preventing chickenpox, highlighting the importance of vaccination in managing varicella outbreaks.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Prevention of varicella: Recommendations of the Advisory Committee on Immunization Practices (ACIP). Centers for Disease Control and Prevention. [2017]

The varicella vaccine used as post-exposure prophylaxis (PEP) for chickenpox in pediatric patients is cost-effective, saving an average of USD 611 per patient while also reducing the quality-adjusted life-year (QALY) loss compared to not using the vaccine.

In a decision analysis involving local epidemiology and medical literature, the study found that PEP with the varicella vaccine resulted in lower costs (USD 320 vs USD 731) and less QALY loss (0.00423 vs 0.01122) when compared to no PEP, demonstrating its effectiveness in preventing chickenpox after exposure.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Cost-effectiveness analysis of varicella vaccine as post-exposure prophylaxis in Hong Kong. Chui, KS., Wu, HL., You, JH.[2013]

The varicella vaccine (Varivax) is 84.5% effective in preventing all cases of chickenpox when given before exposure, and it is 100% effective in preventing severe cases, based on a review of 19 studies.

When given after exposure to the virus, the varicella vaccine is also highly effective in preventing or reducing the severity of the disease, but a two-dose schedule is now recommended to improve effectiveness and prevent outbreaks in high-contact environments.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Varicella vaccine effectiveness in the US vaccination program: a review. Seward, JF., Marin, M., Vázquez, M.[2022]

In a study of 181 healthy children vaccinated with a reformulated varicella vaccine, the overall seroconversion rate was 99%, indicating high efficacy of the vaccine.

Risk factors for breakthrough varicella included being vaccinated at 14 months or younger, having household contact with varicella, and receiving a low titre vaccine, which suggests that vaccination strategies may need to be adjusted to reduce these risks.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Risk factors for breakthrough varicella in healthy children. Lim, YJ., Chew, FT., Tan, AY., et al.[2019]

The live-virus varicella vaccine (Varivax) was licensed in 1995 and initially showed minimal adverse events, but rare risks have been identified since its widespread use.

A case study of an HIV-infected boy revealed that he developed a severe reaction, including dissemination of the vaccine strain of varicella zoster, highlighting potential risks in immunocompromised individuals.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Disseminated vaccine strain varicella as the acquired immunodeficiency syndrome-defining illness in a previously undiagnosed child. Kramer, JM., LaRussa, P., Tsai, WC., et al.[2019]

The live attenuated varicella vaccine demonstrated an efficacy of 87.1% in preventing varicella in a study of 5997 children aged 1 to 12 years, with only six cases in the vaccine group compared to 46 in the placebo group.

The vaccine was found to be safe, with no significant difference in adverse reactions between the vaccine and placebo groups, and a high seroconversion rate of 97.1%, indicating strong immune response in vaccinated children.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Efficacy, safety and immunogenicity of live attenuated varicella vaccine in healthy children in China: double-blind, randomized, placebo-controlled clinical trial. Hao, B., Chen, Z., Zeng, G., et al.[2019]

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