Trial Outcomes & Findings for A Study on the Safety, Effectiveness and Immune Response of Meningococcal Combined ABCWY Vaccine in Healthy Adolescents and Adults (NCT NCT04886154)

Out of 1440 participants enrolled, 3 participants from Phase II (Formulation and Schedule-finding) did not receive vaccination as they did not meet the eligibility criteria, therefore only 1437 participants were included in the Exposed Set and started the study.

A Study on the Safety, Effectiveness and Immune Response of Meningococcal Combined ABCWY Vaccine in Healthy Adolescents and Adults

The solicited administration site events include injection site pain, erythema (redness), swelling and induration. Any solicited administration site AEs = occurrence of the symptom regardless of intensity grade.

The solicited administration site events include injection site pain, erythema (redness), swelling and induration. Any solicited administration site AEs = occurrence of the symptom regardless of intensity grade.

The solicited systemic events include fever (temperature ≥ 38.0°C), nausea, fatigue, myalgia, arthralgia and headache.

The solicited systemic events include fever (temperature ≥ 38.0°C), nausea, fatigue, myalgia, arthralgia and headache.

Unsolicited AEs includes any AE reported in addition to those solicited during the clinical study. Also, any 'solicited' symptom with onset outside the specified period of follow-up for solicited symptoms is reported as an unsolicited adverse event. A SAE is any untoward medical occurrence that results in death, is life-threatening, requires or prolongs hospitalization, results in disability/incapacity and is a congenital anomaly/birth defect in a subject's offspring. AESIs are predefined (serious or non-serious) AEs of scientific and medical concern specific to the product or program, for which ongoing monitoring and rapid communication by the investigator to the sponsor can be appropriate, because such an event might warrant further investigation to characterize and understand it. A participant was considered withdrawn if no study procedures occurred, and no follow-up or further information has been collected from the date of withdrawal or last contact.

Unsolicited AEs includes any AE reported in addition to those solicited during the clinical study. Also, any 'solicited' symptom with onset outside the specified period of follow-up for solicited symptoms is reported as an unsolicited adverse event. A SAE is any untoward medical occurrence that results in death, is life-threatening, requires or prolongs hospitalization, results in disability/incapacity and is a congenital anomaly/birth defect in a subject's offspring. AESIs are predefined (serious or non-serious) AEs of scientific and medical concern specific to the product or program, for which ongoing monitoring and rapid communication by the investigator to the sponsor can be appropriate, because such an event might warrant further investigation to characterize and understand it. A participant was considered withdrawn if no study procedures occurred, and no follow-up or further information has been collected from the date of withdrawal or last contact.

A SAEs is any untoward medical occurrence that results in death, is life-threatening, requires hospitalization or prolongation of existing hospitalization, results in disability/incapacity and is a congenital anomaly/birth defect in the offspring of a study subject. AESIs are predefined (serious or non-serious) AEs of scientific and medical concern specific to the product or program, for which ongoing monitoring and rapid communication by the investigator to the sponsor can be appropriate, because such an event might warrant further investigation to characterize and understand it. A participant was considered withdrawn if no study procedures occurred, and no follow-up or further information has been collected from the date of withdrawal or last contact.

The safety laboratory data included haematological parameters (basophils, eosinophils, Erythrocytes, hemoglobin, leukocytes, lymphocytes, monocytes, platelets and neutrophils), and chemical parameters (Alanine Aminotransferase \[ALT\], Aspartate Aminotransferase \[AST\], Creatinine) Below = value below the laboratory reference range defined for the specified visit and laboratory parameter; Within = value within the laboratory reference range defined for the specified visit and laboratory parameter; Above = value above the laboratory reference range defined for the specified visit and laboratory parameter.

Clinical laboratory testing included hematological and biochemical laboratory values. Any abnormal laboratory test result (e.g., in hematology or clinical chemistry) that was deemed clinically significant by the investigator's medical and scientific judgment, and not related to an underlying disease, was reported as an unsolicited adverse event (AE) unless it was considered by the investigator to be more severe than expected for the participant's condition. The safety laboratory data included hematological parameters (basophils, eosinophils, erythrocytes, hemoglobin, leukocytes, lymphocytes, monocytes, platelets, and neutrophils) and chemical parameters (Alanine Aminotransferase \[ALT\], Aspartate Aminotransferase \[AST\], and creatinine).

The effectiveness of the MenABCWY-2Gen (low \& high dose) vaccine when administered at 0,2- or 0,6-months schedule compared to MenB vaccine administered at 0,6-months schedule, against a panel of 110 randomly selected endemic N. meningitidis serogroup B strains is measured in terms of percentage of samples with bactericidal activity using endogenous complement human Serum Bactericidal Assay (enc-hSBA), which provides a qualitative assessment (yes/no) of the presence of sufficient bactericidal antibodies in human sera to kill a meningococcal strain at a specific dilution of 1:4.

The immune response to the MenABCWY-2Gen (low and high dose) vaccine when administered at 0,2- or 0,6-months schedule compared to MenACWY vaccine (single dose), relative to day 1 in the ABCWY and control groups (0, 6 month schedule) and day 31 in ABCWY (0, 2 month schedule) is measured in terms of number of participants achieving a 4-fold rise in hSBA titers against serogroups A, C, W and Y. The 4-fold rise is defined as: -a post-vaccination hSBA titer ≥ 16 for participants with a pre-vaccination hSBA titer \< 4, -a post-vaccination hSBA titer ≥ 4 times the lower limit of quantitation (LLOQ) for participants with a pre-vaccination hSBA titer ≥LOD but \<LLOQ, and. -a post-vaccination hSBA titer ≥ 4 times the pre-vaccination hSBA titer for participants with a pre-vaccination hSBA titer ≥LLOQ.

Assessed solicited administration site events included injection site pain, erythema (redness), swelling and induration. Any = occurrence of the event regardless of intensity grade.

Assessed solicited administration site events included injection site pain, erythema (redness), swelling and induration. Any = occurrence of the event regardless of intensity grade.

Assessed solicited administration site events included injection site pain, erythema (redness), swelling and induration. Any = occurrence of the event regardless of intensity grade.

Assessed solicited systemic events included fever (temperature ≥ 38.0°C), nausea, fatigue, myalgia, arthralgia and headache. Any = occurrence of the event regardless of intensity grade or relation to the study vaccination.

Assessed solicited systemic events included fever (temperature ≥ 38.0°C), nausea, fatigue, myalgia, arthralgia and headache. Any = occurrence of the event regardless of intensity grade or relation to the study vaccination.

Assessed solicited systemic events included fever (temperature ≥ 38.0°C), nausea, fatigue, myalgia, arthralgia and headache. Any = occurrence of the event regardless of intensity grade or relation to the study vaccination.

Unsolicited AEs includes any AE reported in addition to those solicited during the clinical study. Also, any 'solicited' symptom with onset outside the specified period of follow-up for solicited symptoms is reported as an unsolicited adverse event. A SAE is any untoward medical occurrence that results in death, is life-threatening, requires or prolongs hospitalization, results in disability/incapacity and is a congenital anomaly/birth defect in a subject's offspring. AESIs are predefined (serious or non-serious) AEs of scientific and medical concern specific to the product or program, for which ongoing monitoring and rapid communication by the investigator to the sponsor can be appropriate, because such an event might warrant further investigation to characterize and understand it. A participant was considered withdrawn if no study procedures occurred, and no follow-up or further information has been collected from the date of withdrawal or last contact.

Unsolicited AEs includes any AE reported in addition to those solicited during the clinical study. Also, any 'solicited' symptom with onset outside the specified period of follow-up for solicited symptoms is reported as an unsolicited adverse event. A SAE is any untoward medical occurrence that results in death, is life-threatening, requires or prolongs hospitalization, results in disability/incapacity and is a congenital anomaly/birth defect in a subject's offspring. AESIs are predefined (serious or non-serious) AEs of scientific and medical concern specific to the product or program, for which ongoing monitoring and rapid communication by the investigator to the sponsor can be appropriate, because such an event might warrant further investigation to characterize and understand it. A participant was considered withdrawn if no study procedures occurred, and no follow-up or further information has been collected from the date of withdrawal or last contact.

Unsolicited AEs includes any AE reported in addition to those solicited during the clinical study. Also, any 'solicited' symptom with onset outside the specified period of follow-up for solicited symptoms is reported as an unsolicited adverse event. A SAE is any untoward medical occurrence that results in death, is life-threatening, requires or prolongs hospitalization, results in disability/incapacity and is a congenital anomaly/birth defect in a subject's offspring. AESIs are predefined (serious or non-serious) AEs of scientific and medical concern specific to the product or program, for which ongoing monitoring and rapid communication by the investigator to the sponsor can be appropriate, because such an event might warrant further investigation to characterize and understand it. A participant was considered withdrawn if no study procedures occurred, and no follow-up or further information has been collected from the date of withdrawal or last contact.

A SAEs is any untoward medical occurrence that results in death, is life-threatening, requires hospitalization or prolongation of existing hospitalization, results in disability/incapacity and is a congenital anomaly/birth defect in the offspring of a study subject. AESIs are predefined (serious or non-serious) AEs of scientific and medical concern specific to the product or program, for which ongoing monitoring and rapid communication by the investigator to the sponsor can be appropriate, because such an event might warrant further investigation to characterize and understand it. A participant was considered withdrawn if no study procedures occurred, and no follow-up or further information has been collected from the date of withdrawal or last contact.

Assessed solicited administration site events included injection site pain, erythema (redness), swelling and induration. Any = occurrence of the event regardless of intensity grade.

Assessed solicited administration site events included injection site pain, erythema (redness), swelling and induration. Any = occurrence of the event regardless of intensity grade.

Assessed solicited administration site events included injection site pain, erythema (redness), swelling and induration. Any = occurrence of the event regardless of intensity grade.

Assessed solicited administration site events included injection site pain, erythema (redness), swelling and induration. Any = occurrence of the event regardless of intensity grade.

Assessed solicited systemic events included fever (temperature ≥ 38.0°C), nausea, fatigue, myalgia, arthralgia and headache. Any = occurrence of the event regardless of intensity grade or relation to the study vaccination.

Assessed solicited systemic events included fever (temperature ≥ 38.0°C), nausea, fatigue, myalgia, arthralgia and headache. Any = occurrence of the event regardless of intensity grade or relation to the study vaccination.

Assessed solicited systemic events included fever (temperature ≥ 38.0°C), nausea, fatigue, myalgia, arthralgia and headache. Any = occurrence of the event regardless of intensity grade or relation to the study vaccination.

Assessed solicited systemic events included fever (temperature ≥ 38.0°C), nausea, fatigue, myalgia, arthralgia and headache. Any = occurrence of the event regardless of intensity grade or relation to the study vaccination.

Unsolicited AEs includes any AE reported in addition to those solicited during the clinical study. Also, any 'solicited' symptom with onset outside the specified period of follow-up for solicited symptoms is reported as an unsolicited adverse event. A SAE is any untoward medical occurrence that results in death, is life-threatening, requires or prolongs hospitalization, results in disability/incapacity and is a congenital anomaly/birth defect in a subject's offspring. AESIs are predefined (serious or non-serious) AEs of scientific and medical concern specific to the product or program, for which ongoing monitoring and rapid communication by the investigator to the sponsor can be appropriate, because such an event might warrant further investigation to characterize and understand it. A participant was considered withdrawn if no study procedures occurred, and no follow-up or further information has been collected from the date of withdrawal or last contact.

Unsolicited AEs includes any AE reported in addition to those solicited during the clinical study. Also, any 'solicited' symptom with onset outside the specified period of follow-up for solicited symptoms is reported as an unsolicited adverse event. A SAE is any untoward medical occurrence that results in death, is life-threatening, requires or prolongs hospitalization, results in disability/incapacity and is a congenital anomaly/birth defect in a subject's offspring. AESIs are predefined (serious or non-serious) AEs of scientific and medical concern specific to the product or program, for which ongoing monitoring and rapid communication by the investigator to the sponsor can be appropriate, because such an event might warrant further investigation to characterize and understand it. A participant was considered withdrawn if no study procedures occurred, and no follow-up or further information has been collected from the date of withdrawal or last contact.

Unsolicited AEs includes any AE reported in addition to those solicited during the clinical study. Also, any 'solicited' symptom with onset outside the specified period of follow-up for solicited symptoms is reported as an unsolicited adverse event. A SAE is any untoward medical occurrence that results in death, is life-threatening, requires or prolongs hospitalization, results in disability/incapacity and is a congenital anomaly/birth defect in a subject's offspring. AESIs are predefined (serious or non-serious) AEs of scientific and medical concern specific to the product or program, for which ongoing monitoring and rapid communication by the investigator to the sponsor can be appropriate, because such an event might warrant further investigation to characterize and understand it. A participant was considered withdrawn if no study procedures occurred, and no follow-up or further information has been collected from the date of withdrawal or last contact.

Unsolicited AEs includes any AE reported in addition to those solicited during the clinical study. Also, any 'solicited' symptom with onset outside the specified period of follow-up for solicited symptoms is reported as an unsolicited adverse event. A SAE is any untoward medical occurrence that results in death, is life-threatening, requires or prolongs hospitalization, results in disability/incapacity and is a congenital anomaly/birth defect in a subject's offspring. AESIs are predefined (serious or non-serious) AEs of scientific and medical concern specific to the product or program, for which ongoing monitoring and rapid communication by the investigator to the sponsor can be appropriate, because such an event might warrant further investigation to characterize and understand it. A participant was considered withdrawn if no study procedures occurred, and no follow-up or further information has been collected from the date of withdrawal or last contact.

A SAEs is any untoward medical occurrence that results in death, is life-threatening, requires hospitalization or prolongation of existing hospitalization, results in disability/incapacity and is a congenital anomaly/birth defect in the offspring of a study subject. AESIs are predefined (serious or non-serious) AEs of scientific and medical concern specific to the product or program, for which ongoing monitoring and rapid communication by the investigator to the sponsor can be appropriate, because such an event might warrant further investigation to characterize and understand it. A participant was considered withdrawn if no study procedures occurred, and no follow-up or further information has been collected from the date of withdrawal or last contact.

A SAEs is any untoward medical occurrence that results in death, is life-threatening, requires hospitalization or prolongation of existing hospitalization, results in disability/incapacity and is a congenital anomaly/birth defect in the offspring of a study subject. AESIs are predefined (serious or non-serious) AEs of scientific and medical concern specific to the product or program, for which ongoing monitoring and rapid communication by the investigator to the sponsor can be appropriate, because such an event might warrant further investigation to characterize and understand it. A participant was considered withdrawn if no study procedures occurred, and no follow-up or further information has been collected from the date of withdrawal or last contact.

A SAEs is any untoward medical occurrence that results in death, is life-threatening, requires hospitalization or prolongation of existing hospitalization, results in disability/incapacity and is a congenital anomaly/birth defect in the offspring of a study subject. AESIs are predefined (serious or non-serious) AEs of scientific and medical concern specific to the product or program, for which ongoing monitoring and rapid communication by the investigator to the sponsor can be appropriate, because such an event might warrant further investigation to characterize and understand it. A participant was considered withdrawn if no study procedures occurred, and no follow-up or further information has been collected from the date of withdrawal or last contact.

The percentages of strains killed measured by enc-hSBA against a randomly selected panel of strains and the corresponding exact 2-sided 95% CIs based on Clopper-Pearson method is calculated in all groups at 1 month after the last vaccination of MenABCWY-2Gen (low and high dose) vaccine administered at 0,2 and 0,6-months schedule and of the MenB vaccine administered at 0,6-months schedule.

The immune response to MenABCWY-2Gen (low and high dose) administered at 0,2 and 0,6-months schedule and MenB vaccine administered at 0,6-months schedule is evaluated by measuring bactericidal activity using a qualified AO hSBA against a standard panel of serogroup B indicator strains.

The immune response to MenABCWY-2Gen (low and high dose) vaccine when administered at 0,2- or 0,6-months schedule and to MenB vaccine administered at 0,6-months schedule, relative to day 1 in ABCWY (0,6 month schedule) and control groups and day 31 in ABCWY (0,2 month schedule) is measured in terms of number of participants achieving a 4-fold rise in hSBA titers against serogroup B indicator strains. The 4-fold rise is defined as: -a post-vaccination hSBA titer ≥ 16 for participants with a pre-vaccination hSBA titre \< 4, -a post-vaccination hSBA titer ≥ 4 times the LLOQ for participants with a pre-vaccination hSBA titer ≥LOD but \<LLOQ, and. -a post-vaccination hSBA titer ≥ 4 times the pre-vaccination hSBA titer for participants with a pre-vaccination hSBA titer ≥ LLOQ.

For each B strains, the GMTs are calculated with their associated 2-sided 95% CIs, by exponentiating the corresponding log-transformed means and their 95% CIs.

For each B strains, the GMRs (post-vaccination/ Baseline) are calculated with their associated 2-sided 95% CIs, by exponentiating the corresponding log-transformed means and their 95% CIs.

The number of participants with hSBA titers ≥ LLOQ and the corresponding exact 2-sided 95% CIs based on Clopper-Pearson method are calculated. Baseline (pre-vaccination) was evaluated at Day 1 for 0,6 schedules and Control, at Month 1 for 0,2 schedules. Post vaccination was evaluated at Month 7 for all MenABCWY groups, at Month 1 for Control group.

The immune response to the MenABCWY-2Gen (low and high dose) vaccine when administered at 0,6-months schedule, relative to day 1 was measured in terms of percentage of participants achieving a 4-fold rise in hSBA titers against serogroups A, C, W and Y. Serum bactericidal activity against MenACWY were determined by using a validated AO hSBA. The 4-fold rise is defined as: -a post-vaccination hSBA titre ≥ 16 for participants with a pre-vaccination hSBA titre \< 4, -a post-vaccination hSBA titre ≥ 4 times the LLOQ for participants with a pre-vaccination hSBA titre ≥ LOD but \< LLOQ, and. -a post-vaccination hSBA titre ≥4 times the pre-vaccination hSBA titre for participants with a pre-vaccination hSBA titre ≥ LLOQ.

The immune response to the MenABCWY-2Gen (low and high dose) vaccine (0,2- and 0,6-months schedule) and MenACWY vaccine (single dose) was evaluated by hSBA titers which are logarithmically transformed (base10) to fulfil the normal distribution assumption. For each serogroup A, C, W and Y, the GMTs are calculated with their associated 2-sided 95% CIs, by exponentiating the corresponding log-transformed means and their 95% CIs.