MenHibrix Vaccine finally approved on its third try.

So, GKS finally got their new combo vaccine approved after being denied approval twice before. GKS’ MenHibrix combines GSK’s meningococcal and Hib vaccines.

According to GKS’s own website:

  • “MENHIBRIX is a vaccine indicated for active immunization to prevent invasive disease caused by Neisseria meningitidis serogroups C and Y and Haemophilus influenzae type b. MENHIBRIX is approved for use in children 6 weeks of age through 18 months of age”
  •  Approximately 300 cases [of meningococcal disease] are reported annually in infants and toddlers under two years of age. 1 out of every 10 of those cases lead to death. So, about 30 deaths per year from this disease were expected from this disease.
  • According to the WHO, prior to vaccination, children under five in the US ranked among the highest to contract Hib Meningitis at .03% to .09% of US children contracting the disease.

According to GKS’ prescribing information on this new vaccine:

Following doses 1, 2, and 3, 1.8% (137/7,444) of participants who received MENHIBRIX reported at least one serious adverse event within the 31-day period. Up to 6 months following the last vaccine administered (doses 1, 2, and 3) or until administration of dose 4, 4.8% (365/7,362) of participants who received MENHIBRIX  reported at least one serious adverse event.

Given the actual population of the children in the US compared to the trial size, 1.8% and 4.8% of children is a whole lot of children suffering SERIOUS side effects (as defined by the vaccine manufacturer, not even the parents) as a result of this new vaccine.

In addition, the prescribing information for Menhebrix also mentioned this:

The following adverse events were included based on one or more of the following factors: seriousness, frequency of reporting, or strength of evidence for a causal relationship to HIBERIX.

  • General Disorders and Administration Site Conditions: Extensive swelling of the vaccinated limb, injection site induration.
  • Immune System Disorders: Allergic reactions (including anaphylactic and anaphylactoid reactions), angioedema.
  • Nervous System Disorders: Convulsions (with or without fever), hypotonichyporesponsive episode, somnolence, syncope or vasovagal responses to injection.
  • Respiratory, Thoracic, and Mediastinal Disorders: Apnea.
  • Skin and Subcutaneous Tissue Disorders: Rash, urticaria.
The prescribing info also had the following precautions and warnings:

5.1 Guillain-Barré Syndrome
If Guillain-Barré syndrome has occurred within 6 weeks of receipt of a prior vaccine
containing tetanus toxoid, the decision to give any tetanus toxoid-containing vaccine, including
MENHIBRIX, should be based on consideration of the potential benefits and possible risks.
5.2 Syncope
Syncope (fainting) can occur in association with administration of injectable vaccines,
including MENHIBRIX. Syncope can be accompanied by transient neurological signs such as
visual disturbance, paresthesia, and tonic-clonic limb movements. Procedures should be in place
to avoid falling injury and to restore cerebral perfusion following syncope.
5.3 Apnea in Premature Infants
Apnea following intramuscular vaccination has been observed in some infants born
prematurely. Decisions about when to administer an intramuscular vaccine, including
MENHIBRIX, to infants born prematurely should be based on consideration of the individual
infant’s medical status, and the potential benefits and possible risks of vaccination.
5.4 Preventing and Managing Allergic Vaccine Reactions
Prior to administration, the healthcare provider should review the patient’s immunization
history for possible vaccine hypersensitivity. Epinephrine and other appropriate agents used for
the control of immediate allergic reactions must be immediately available should an acute
anaphylactic reaction occur.
5.5 Altered Immunocompetence
Safety and effectiveness of MENHIBRIX in immunosuppressed children have not been
evaluated. If MENHIBRIX is administered to immunosuppressed children, including children
receiving immunosuppressive therapy, the expected immune response may not be obtained.
5.6 Tetanus Immunization
Immunization with MENHIBRIX does not substitute for routine tetanus immunization.

I guess I just wanted you to know the statistics, even the ones the normal press releases don’t tell you about.

3 Comments

  1. John

    Hi Dawn,

    Side effects are not the same thing as adverse events. An adverse event is any adverse health condition reported by a patient, irrespective of causality. “Side effect” implies causality. The rate of adverse events reported in the Menhibrix treated group was actually slightly less than in the control group. So it appears to be a pretty clean vaccine in terms of side effects.

    Hib and invasive meningitis are two separate diseases. The pre-vaccine incidence of invasive meningococcal disease was about 1000 cases per year, with about 10% fatality and about 25% suffering hearing loss or mental retardation.

    Admittedly the risk from Hib and meningococcal disease are relatively modest in the overall scheme of things, but overall the risk/benefit ratio appears favorable, with the prevention of about 300 deaths per year (0.05% of 4 million births x 1/10 fatality for Hib plus 100 for meningococcal disease) and about 700 cases of deafness and mental retardation.

    I think most parents would vigorously avoid exposing their child to a vaccine or drug that caused 300 deaths and 700 cases of neurological injury per year. Doesn’t it make equal sense to provide your child with an immunization that prevents a similar number of deaths and injuries?

    • Dawn

      Regarding side effects and adverse events. That is true. I apologize for my error in semantics. I think people might consider adverse eventss still equally important to take into consideration though as if there was distinct causation.

      I think they are all important considerations and to overlook adverse events and proclaim that they did NOT cause is equally as incorrect as saying they did for sure. Not that you did that. Your tone was very respectful and honest and very much appreciated.

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