Sunday, October 25, 2009

FDA plans (dated June 26, 2009) for safety evaluation of Swine Flu Vaccines

Here is an FDA briefing document for the Vaccines and Related Biological Products Advisory Committee meeting of July 23, 2009. It lays out the plan that has been followed since then. The plan involved very limited safety data collection before starting vaccinations, and a detailed plan for obtaining data on adverse reactions after vaccinations have been given.

Although scientifically sound, and apparently meeting FDA's need for "adequate" safety data, the glaring problem with this plan is that it will fail to identify significant vaccine problems (such as development of chronic autoimmune conditions) until after tens or hundreds of millions have been vaccinated. Excerpts follow from "Regulatory Considerations Regarding the Use of Novel Influenza A (H1N1) Virus Vaccines." [The italics and color are mine--Nass]
Section 5.1.6. Safety Monitoring:
Subjects should record age appropriate local and systemic reactogenicity for seven days after each vaccination. In addition, unsolicited adverse events, serious adverse events (SAEs), and deaths should be assessed for 21 days after each vaccination. Subjects should be followed for 6 months after the second vaccination for assessment of SAEs, deaths and new onset chronic medical conditions. If the study included evaluation of investigational adjuvants, subjects should be followed for 12 months after the second vaccine dose for occurrence of SAEs, deaths and new onset chronic medical conditions. For studies that include evaluation of antigen formulated with an investigational adjuvant, we recommend safety laboratory evaluations at baseline and at early and late time points post-vaccination (e.g., days 7 -10, and 21).

5.1.7 Endpoints

Safety: For each antigen dose and age group:

• The incidence of solicited local and systemic events within 7 days of each
vaccine dose
• Occurrence of unsolicited adverse events, serious adverse events (SAEs) and
new onset chronic medical conditions throughout the entire study, including
the 6-12 month follow-up period after the last dose of study vaccine

6.0 Post Marketing Evaluation:

FDA and CDC together with other agencies in the Dept. of Health and Human
Services (DHHS) are working to strengthen their ability to rapidly detect and
evaluate potential safety signals following administration of novel influenza A
(H1N1) virus vaccines. At the time of initial use of these vaccines there will be limited data from clinical studies evaluating safety. In addition, there is a possibility that some vaccines may be used under EUA (see Section 4.0).
Because of these considerations, as well as the 1976 swine influenza vaccine
experience, a number of methods to enhance surveillance for adverse events
following administration of novel influenza A (H1N1) vaccines will be utilized.

Current plans are to monitor adverse events through reports to the Vaccine
Adverse Event Reporting System (VAERS), as well as through diagnoses and
related data in the Vaccine Safety Data (VSD) link system, the Department of
Defense (DoD), Centers for Medicaid and Medicare Services (CMS), the
Veterans’ Health Administration (VHA), and other population based
(MCO/HMO) health care organizations. DHHS is coordinating these activities.
One challenge is linking adverse event data with vaccine administration data and DHHS is exploring ways to improve the link between vaccine receipt and adverse
event data.

FDA, CDC and their contractors are developing data mining tools, daily reports
designed for novel influenza A (H1N1) vaccines, and vaccinee cards with vaccine
and adjuvant details, including the manufacturer, lot numbers and date of
administration, as well as “how to make a VAERS” report” information to
enhance adverse event reporting.

FDA and CDC are planning safety surveillance systems which adapt to the
various scenarios of public/private payment and administration of vaccines. Both
agencies are working with states and on a national level to prepare multiple safety
surveillance systems, which could be adapted to study sub-populations (e.g.,
young children, adolescents, pregnant women and the elderly) and to respond to
the epidemiologic data identifying which populations should be targeted for early
vaccination. Furthermore, FDA is also developing international collaborations for
vaccine safety surveillance (standard case definitions, safety surveillance studies,
communication, and risk management activities). FDA will be working with
manufacturers and government agencies to coordinate surveillance plans. Given
the limitations of clinical trial data prior to vaccine utilization, post-marketing or post-EUA surveillance studies are critical to evaluate safety and effectiveness of novel influenza A (H1N1) vaccines.

From the US government's "Federal Plans to Monitor Immunization Safety for the Pandemic H1N1 Influenza Vaccination Program"
comes the following statement, a tacit acknowledgement that determining vaccine safety will require plenty of time:

"... efforts have been made to enhance safety systems for H1N1 monitoring. The primary intent of these safety enhancements is to accelerate the availability of safety data to inform the immunization program, health care providers, and the public. Despite these efforts, there will inevitably be a time delay between when safety signals arise and when science is available to inform assessments of whether such signals are due to the vaccine or temporally related coincidental events that are anticipated. The time that is required for such determinations is primarily dependent on the incidence of the health event under investigation, how the health event is diagnosed and reported to large-linked databases, and the magnitude of the risk that is being explored. Ultimately, the safety profile of the vaccine needs to be considered in the context of the benefits of vaccination, which includes the disease epidemiology and the vaccine effectiveness. Rapid scientific exploration of the safety and effectiveness of the vaccine, a transparent process for such evaluations, and rapid and ongoing communications are important for ensuring optimal policy decisions and public confidence in the immunization program. "

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