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Signaling
a potential breakthrough for immunization programs in resource-poor
countries, researchers today announced at the American Society of Tropical
Medicine and Hygiene (ASTMH) conference that regulatory authorities—after
conducting a rigorous review of stability data—will for the first time allow
a vaccine in Africa to be transported and stored for as long as four days
without refrigeration or even an icepack.
The meningitis A vaccine known as
MenAfriVac®, created to meet the needs of Africa's meningitis belt, can now
be kept in a controlled temperature chain (CTC) at temperatures of up to 40°C
for up to four days, a decision that could help increase campaign efficiency
and coverage and save funds normally spent maintaining the challenging cold
chain during the "last mile" of vaccine delivery.
The outcome of the review and
decisions of the Drugs Controller General of India (DCGI), supported by a
Health Canada analysis and confirmed by the World Health Organization (WHO)
Vaccines Pre-qualification Programme, was revealed during a presentation this
afternoon at the ASTMH conference in Atlanta by Godwin Enwere, MD, medical
director for the Meningitis Vaccine Project. The regulatory approval has the
effect of permitting the re-labeling of MenAfriVac®, while ensuring that the
vaccine remains effective and safe throughout its life cycle.
Costing less than US$0.50 per
dose, the innovative vaccine that is manufactured by Serum Institute of India
Ltd. (SIIL) has dramatically reduced disease burden in the first countries to
introduce it, according to recently-published findings. MenAfriVac® is the
first vaccine designed specifically to help health workers eliminate
meningococcal A epidemics from Africa's "meningitis belt," which
includes 26 countries from Senegal to Ethiopia.
"The potential for some
vaccines to remain safely outside the cold chain for short periods of time
has been widely known for over 20 years," said Dr. Michel Zaffran,
director of Optimize, the PATH-WHO collaboration aimed at improving
immunization systems and technologies. "But this is the first time that
a vaccine intended for use in Africa has been tested and submitted to
regulatory review and approved for this type of use. And we expect this
announcement to build momentum for applying the CTC concept to other vaccines
and initiatives, allowing us to save more lives in low-income
countries."
Evidence of the heat stability of
MenAfriVac® was validated by a team of experts from WHO, PATH, SIIL, and
Health Canada. In collaboration with the government of Benin, the Meningitis
Vaccine Project (MVP), Optimize, and the WHO regional office for Africa, a
pilot use of the MenAfrivac® vaccine in a CTC will be conducted during the
upcoming MenAfriVac® campaign in the northern part of the country, from
November 15 through 25. Benin is the 10th country to introduce the vaccine,
as well as the first country to work with the new CTC implementation
guidelines, developed through WHO's Immunization Practices Advisory
Committee.
"Vaccines save and improve
lives wherever they are used, but reaching the millions of children in last
mile communities like those in rural Africa continues to challenge us,"
said Dr. Orin Levine, director of Vaccine Delivery at the Bill & Melinda
Gates Foundation. "Today's announcement marks a new milestone because it
allows us to extend the delivery of the MenAfriVac vaccine from the
traditional cold chain and reach more people across Africa, safely and
efficiently."
New evidence of vaccine's efficacy
in combating meningitis A in Africa
Other research discussed at the
conference in Atlanta suggests that MenAfriVac® has already begun to do its
job, eliminating meningitis A in the first countries where it was introduced.
The authors of a recent paper in Clinical Infectious Diseases say they expect
to see the impact repeated in all the countries that roll out the new
vaccine.
The new article reports that swabs
taken from the throats of thousands of Burkina Faso residents prior to and in
the year that followed the introduction of MenAfriVac® suggested that
infection with the bacteria causing meningitis A had been eliminated in
vaccinated and unvaccinated populations in Burkina Faso. According to one of
the authors, Dr. Marie-Pierre Préziosi, director of the Meningitis Vaccine
Project, "our findings show that the bacteria causing meningitis A have
disappeared from the noses and throats of those too old or too young to have
received the vaccine, resulting from a phenomenon known as 'herd
immunity.'"
"From early evidence in the
first introducing countries, based on public health surveillance combined
with these hard data, we can say the signs are very promising," Préziosi
said. "We have herd immunity, which we were expecting. And we can also
show that after introduction in Burkina Faso, we saw the lowest level of
epidemic meningitis in 15 years."
She noted that the experience of
Chad is particularly dramatic because the country's limited cold chain
capacity had led authorities to immunize target populations in four phases.
The first was carried out in 2011, and the other regions were set to receive
the vaccine this year. The effect of the vaccine seemed evident almost
immediately. In 2012, not a single group A meningitis case was identified in
the three vaccinated areas, while the regions that had not yet received the
vaccine suffered severe outbreaks caused by meningitis A.
For more than 100 years,
sub-Saharan Africa has suffered from epidemics that exact a terrible and
deadly toll. Across the meningitis belt, from Dakar to Addis Ababa, as many
as 450 million people are at risk from the disease. Epidemics of meningitis A
occur every 7 to 14 years and are particularly devastating to children and
young adults.
"The introduction of
MenAfriVac® in Burkina Faso in 2010 was the start of an exciting journey for the
meningitis A vaccine. This revolutionary vaccine continues to break new
ground as it rolls out across the meningitis belt," said Steve Davis,
PATH president and CEO. "We are grateful for all the institutions and
the individuals who have made this vision a reality. Our efforts won't stop
here. Our next step will be to develop a thermostable multivalent meningitis
vaccine that protects against the other causes of meningitis in the region.
We will stay ahead of this disease that causes such destruction to health
systems, economies, and Africa's most valuable resource—its children and
young people."
MenAfriVac®, first vaccine
developed specifically for Africa
Developed by the MVP partnership
between the WHO and PATH—with support from the Bill & Melinda Gates
Foundation?the meningococcal A conjugate vaccine MenAfriVac® provides African
health authorities, for the first time, with an affordable, long-term
solution that protects even young children against meningitis A (group A
Neisseria meningitidis).
MenAfriVac® was developed to meet
the need in Africa for a safe, effective, and affordable vaccine. The vaccine
is now being tested on children who are less than one year of age to ensure
it can be included safely in the routine vaccination programs, according to
Godwin Enwere.
"If we can immunize the
infants, then we will be able to make exponential progress in preventing
epidemics because all the age groups most at risk of disease will be
protected for a significant period of time," said Enwere, who is the author
of a paper being presented on the infant study at the ASTMH conference.
The rapid development of
MenAfriVac® has happened thanks in large part to SIIL, which worked closely
with partners to overcome the 20-year lag between the time a vaccine is
approved for use in wealthy nations and when it is used in the nations that
suffer from the greatest burden of disease.
"By going beyond that vision,
and by asking ourselves what can be done to make this product even more
useful in hard-to-reach areas, the PATH-WHO-SIIL team succeeded in getting
more out of limited resources," said Dr. Cyrus Poonawalla, SIIL
chairman. "We have opened a door that we can expect other vaccine
manufacturers to walk through in the future."
Clinical trials, carried out in
India, the Gambia, Ghana, Mali, and Senegal, beginning in 2005, showed the
vaccine to be safe and highly effective. Indian regulatory authorities
granted marketing authorization for export and use of MenAfriVac® in December
2009. In June 2010, the vaccine was prequalified by WHO, which guarantees
that the vaccine meets international standards of quality, safety, and
efficacy. "The process of developing this vaccine and planning for its
introduction helped strengthen systems in Africa for disease surveillance,
clinical research, pharmacovigilance, vaccine regulation and vaccination
logistics," Préziosi said.
The GAVI Alliance has thus far
contributed US$162 million to the effort to eliminate meningococcal A
meningitis in Africa, and has committed to supporting its introduction across
the remaining 15 or so nations.
Progress and impact of new
meningitis vaccine
As of today, with the support of
the GAVI Alliance, UNICEF, PATH, WHO, and their partners, along with the
commitment of national governments, MenAfriVac® vaccination campaigns have
taken place in Burkina Faso, Cameroon, Chad, Ghana, Mali, Niger, Nigeria,
Senegal, and Sudan. Benin is joining the group this week. It is estimated
that by the end of 2012, more than 100 million people in Africa's meningitis
belt will have received the lifesaving new vaccine that is already
demonstrating significant impact on the course of the disease that has
wreaked havoc for more than a century on the continent.
"The new flexibility in
delivering this vaccine represents a huge step forward," said Zaffran,
director of Optimize, the PATH-WHO collaboration. "It took the work of a
dedicated team to break through political, operational, and regulatory
barriers to get this vaccine re-labeled."
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