In short
This article summarizes clinical trials investigating the use of a recombinant Neisseria meningitidis group B NHBA fusion protein vaccine produced in E. coli cells and adsorbed on aluminum hydroxide. This vaccine is being studied for prevention of meningococcal disease caused by Neisseria meningitidis bacteria. The trials examine the vaccine's safety, tolerability, and ability to produce an immune response in different populations, including healthy adolescents, infants, and adults with certain medical conditions.
At a glance
- Vaccine Components
- Recombinant Neisseria meningitidis group B NHBA, NadA, and fHbp fusion proteins, plus outer membrane vesicles
- Study Populations
- Healthy adolescents, infants, adults with asplenia, adults with generalized myasthenia gravis
- Primary Objectives
- Safety, tolerability, immunogenicity of different dosing schedules
- Key Outcome Measures
- Adverse events, antibody responses (hSBA titers), seroconversion rates
- Administration
- Intramuscular injection, 2-3 doses over months
- Follow-up Duration
- Varies by trial, some up to 48 months post-vaccination
What is this vaccine?
This vaccine, known by the brand name Bexsero, is a recombinant vaccine designed to protect against meningococcal disease caused by Neisseria meningitidis serogroup B bacteria. It contains several key components:
- Recombinant Neisseria meningitidis group B NHBA fusion protein
- Recombinant Neisseria meningitidis group B NadA protein
- Recombinant Neisseria meningitidis group B fHbp fusion protein
- Outer membrane vesicles (OMV) from Neisseria meningitidis group B
These components are produced using recombinant DNA technology in E. coli cells and are adsorbed on aluminum hydroxide to enhance the immune response.
How does it work?
The vaccine works by stimulating the body's immune system to produce antibodies against specific proteins found on the surface of meningococcal B bacteria. When a vaccinated person is exposed to these bacteria, their immune system recognizes the proteins and can quickly mount a defense, preventing infection.
What does it treat?
This vaccine is designed to prevent meningococcal disease caused by Neisseria meningitidis serogroup B. Meningococcal disease can lead to serious conditions such as:
- Meningitis (infection of the lining of the brain and spinal cord)
- Septicemia (blood infection)
These conditions can be life-threatening and may cause severe long-term complications in survivors.
How is it administered?
The vaccine is given as an intramuscular injection, typically in the upper arm or thigh. The dosing schedule may vary depending on the age of the recipient and the specific vaccination strategy being used. In general:
- Infants and young children may receive multiple doses starting as early as 2 months of age
- Adolescents and adults typically receive 2 doses, with the second dose given at least 1 month after the first
Your healthcare provider will determine the appropriate schedule based on your age and risk factors.
How effective is it?
Clinical trials have shown that the vaccine is effective in producing an immune response against meningococcal B strains. The effectiveness is measured by looking at the percentage of people who develop protective antibody levels after vaccination. While the exact level of protection can vary, studies have shown that a significant proportion of vaccinated individuals develop protective antibody levels against multiple meningococcal B strains.
Is it safe?
The vaccine has been extensively studied and has a good safety profile. It has been approved for use by regulatory agencies in many countries, including the European Medicines Agency (EMA) and the U.S. Food and Drug Administration (FDA). As with all vaccines, it undergoes continuous safety monitoring.
What are the potential side effects?
Like all vaccines, this one can cause side effects, although not everyone experiences them. Common side effects may include:
- Pain, redness, or swelling at the injection site
- Fever
- Irritability
- Drowsiness
- Loss of appetite
- Muscle and joint pain
Most side effects are mild and resolve within a few days. Serious allergic reactions are rare but can occur. Your healthcare provider can provide more information about potential side effects.
Who should get this vaccine?
The vaccine is recommended for individuals at increased risk of meningococcal disease, including:
- Infants and young children
- Adolescents
- People with certain medical conditions that weaken the immune system
- Laboratory workers who may be exposed to meningococcal bacteria
- People living in or traveling to areas with high rates of meningococcal disease
It's particularly important for people with asplenia (absence of a functioning spleen) to receive this vaccine, as they are at higher risk of severe bacterial infections.
What ongoing research is being done?
Several clinical trials are currently underway to further evaluate the safety, effectiveness, and optimal use of this vaccine:
- A study is assessing the vaccine's safety and immune response in healthy adolescents aged 11 to 14 years, comparing different dosing schedules.
- Another trial is evaluating the vaccine's immunogenicity and safety in adult patients with asplenia, comparing it to healthy controls.
- A multicenter study is comparing three different meningococcal B vaccine strategies in adults with asplenia.
These ongoing studies aim to provide more data on the vaccine's performance in different populations and to optimize vaccination strategies for maximum protection against meningococcal disease.