Minutes of the Vaccine Sub-Committee Teleconference
22 August 2005
(with correction of minor typographical error)
Welcome and Apologies
The meeting opened at 9.30am.
Present: Associate Professor Richard Robson (Chair), Dr Tim Blackmore, Associate Professor David Holdaway, Dr Rod Ellis-Pegler, Dr Stewart Reid, Professor Jeff Weston, Alison MacDonald (Secretary), Marie Prescott, Rob Allman and Stewart Jessamine.
NEW MEDICINE APPLICATIONS UNDER SECTION 23
MeNZB (Meningococcal B) injection suspension 25mcg/0.5mL TT50-7090
OBJECTIVE: To further consider the application to the Minister to introduce a fourth dose of Meningococcal B (MeNZB) Vaccine for children.
Conflict of interest statement
As with earlier applications for this vaccine Dr Reid stated a conflict of interest, as he has been a member of the Meningococcal B Vaccine Project Committee for the past five years. The committee noted his declaration and confirmed its earlier decision that Dr Reid could participate in the meeting by answering questions specifically asked by other committee members, but that Dr Reid would abstain from the decision making process.
The committee noted that study V60P6 and accompanying data had been sent to each committee member for further consideration.
Continuation data comprised of a subgroup of 45 infants under 6 months of age who had been administered with a fourth dose of vaccine.
The committee agreed that study V60P6 data demonstrated that a fourth dose of MeNZB administered five months after completion of a 3 dose vaccination schedule in children aged under 6 months at first vaccination produced a brisk immune response in a significant number of study participants.
The committee considered that while this evidence demonstrated that a booster dose would be effective if administered at this time point, the data also indicates that the initial vaccination schedule has produced a strong memory effect against the epidemic strain. This memory effect indicates that the vaccination is likely to remain effective against infection even in infants whose SBA titres had fallen below levels used as surrogate markers of efficacy against infection with the epidemic strain.
The committee is reassured that the data presented indicates ongoing levels of protection against the epidemic strain in this high risk group of infants five months after completion of the 3 dose vaccination schedule. It therefore concluded that there was insufficient evidence of waning immunity to warrant the addition of a booster dose in any age group at this point in time.
The committee accepted that the data supplied however, did demonstrate that administration of a fourth dose did “boost “ the immune response in previously primed individuals.
The committee then considered what information it would require to recommend the introduction of a fourth dose of vaccine. Following discussion, the committee concluded that real-time data from the vaccinated cohorts demonstrating loss of protection (i.e. vaccine failure) over time would be required to indicate the most appropriate time point for introduction of a fourth “booster” dose. This data could be obtained either through further epidemiological studies or through the vaccine safety-monitoring scheme that is currently in place.
The committee concluded that the data presented further supported the efficacy of the vaccine when used in its current schedule, however at this point in time it did not consider that the evidence indicated a clinical need (as required for Section 23 approval) for a 4th dose of vaccine in any age group. The committee acknowledged that the epidemiology of the disease was variable and agreed that it would re-consider its advice urgently if the data indicated a rapid change in the disease pattern indicating increasing cases in vaccinated children over time.
That the application for MeNZB (Meningococcal B) vaccine for an extension to introduce the possibility of administering a fourth dose of vaccine:
The meeting closed at 10.10 am