In short
This article discusses a clinical trial called SPLEMENGO, which aims to assess the safety and immune response of different meningococcal B vaccine strategies in adults who have undergone spleen removal (asplenia). The study focuses on the use of vaccines containing Neisseria Meningitidis Group B Fhbp Protein Subfamily A and B, specifically evaluating the effectiveness of Bexsero and Trumenba vaccines in this patient population.
At a glance
- Study Name
- SPLEMENGO
- Study Type
- Multicenter, randomized, phase III trial
- Primary Objective
- Assess immunogenicity of three meningococcal B vaccine strategies in asplenic adults
- Vaccines Studied
- Bexsero and Trumenba (containing Neisseria Meningitidis Group B Fhbp Protein Subfamily A and B)
- Study Duration
- 4 years follow-up
- Key Inclusion Criteria
- Adults 18-75 years old with asplenia for at least 2 weeks
- Primary Endpoint
- Proportion of responders one month after completing vaccination
- Secondary Objectives
- Evaluate persistence of immune response, assess determinants of immune response, evaluate safety
What is Neisseria Meningitidis Group B FHBP Protein?
Neisseria meningitidis is a bacterium that can cause serious infections, including meningitis (inflammation of the protective membranes covering the brain and spinal cord) and septicemia (blood poisoning). The Group B strain is one of the most common causes of meningococcal disease in many parts of the world.
The vaccine being studied contains proteins from this bacterium, specifically the FHBP (Factor H Binding Protein) from both subfamily A and subfamily B. These proteins are important components that help stimulate the immune system to protect against meningococcal B infections.
About Trumenba: The Vaccine Under Study
The vaccine being investigated in this trial is called Trumenba. It is a meningococcal group B vaccine that contains: Neisseria meningitidis group B FHBP protein subfamily A: This is one of the main components of the vaccine. Neisseria meningitidis group B FHBP protein subfamily B: This is another key component of the vaccine.
Trumenba is given as a suspension for injection, typically administered into a muscle (intramuscularly). It's designed to help protect against meningococcal disease caused by group B Neisseria meningitidis bacteria.
The SPLEMENGO Trial: Purpose and Objectives
The SPLEMENGO trial is a phase III clinical trial designed to assess the effectiveness and safety of three different meningococcal B vaccine strategies in adults who have had their spleen removed (asplenic patients). The main goals of this study are:
- Primary Objective: To evaluate how well the immune system responds to the vaccines one month after completing the vaccination schedule.
- Secondary Objectives:
- To assess how long the immune response lasts, checking at 12, 24, 36, and 48 months after the first vaccination.
- To identify factors that influence the immune response to each vaccine strategy.
- To evaluate the safety of the vaccines, looking at both clinical symptoms and laboratory test results.
- To assess the safety and effectiveness of the vaccines in adults over 65 years old.
Who Can Participate in the Trial?
The trial is looking for participants who meet specific criteria:
- Inclusion Criteria:
- Adults aged 18 to 75 years old
- Have had their spleen removed at least 2 weeks before the study
- Have evidence of spleen removal (visible Howell Jolly bodies in their blood)
- Women of childbearing age must use effective contraception during the first 9 months of the study
- Exclusion Criteria: People cannot participate if they:
- Have previously received a meningococcal B vaccine
- Have bleeding disorders that prevent intramuscular injections
- Are pregnant or breastfeeding
- Have severe acute illnesses
- Have certain medical conditions or are taking medications that might affect their immune response
Trial Procedures and Duration
The SPLEMENGO trial involves:
- Three different vaccine strategies being tested
- Vaccinations given over a 7-month period
- Follow-up visits for up to 48 months (4 years) after the first vaccination
- Blood tests to measure the immune response at various time points
Safety Considerations
The trial carefully monitors the safety of the vaccines. Participants should be aware that:
- They cannot receive certain other vaccines during the first 7 months of the study
- Some vaccines (like flu shots) are allowed at specific times
- They should report any side effects or health changes to the study team
Potential Benefits of the Study
While individual participants may or may not benefit directly from the study, the research aims to:
- Improve protection against meningococcal B disease for people without a spleen
- Determine the best vaccination strategy for this vulnerable group
- Contribute to the broader understanding of vaccine effectiveness in different populations