Swine flu vaccine expected to be rolled out
Carly Laird reported this story on Friday, September 11, 2009 12:50:00
ELIZABETH JACKSON: Australia's chief medical officer professor Jim Bishop says preliminary trial results from a swine flu vaccine look promising.
The vaccine will now go through an approval process with the Therapeutic Goods Administration before it's used on the most vulnerable groups of Australians.
So far there have been 169 swine flu related deaths in Australia since the pandemic began earlier this year and there are currently 336 people in hospital with the virus.
Carly Laird reports.
CARLY LAIRD: Since the swine flu pandemic broke out in Mexico in April nearly 170 people in Australia have died from this type of the virus.
Australia's chief medical officer professor Jim Bishop says it's good news that the rates of infection are now slowing down.
JIM BISHOP: We're seeing that the intensity of the pandemic through Australia is lessening and we're seeing less numbers now in hospital and in intensive care than we did see.
CARLY LAIRD: The preliminary results from two trials of a swine flu vaccine that were released today show that one dose should be enough to immunise adults against the virus.
JIM BISHOP: So these two trials can be taken together with some verbal information we've got from NIH trials, which also suggest one does may be sufficient in adults. And the Chinese have also reported that one dose of their vaccine will be sufficient in adults.
CARLY LAIRD: But he says children may need more than that.
JIM BISHOP: Now I'd stress that we don't have information on children and the history would tell us that often children with these flu vaccines might require two doses.
CARLY LAIRD: Alan Hampson is the chair of the Australia Influenza Specialist Group. He agrees that this is good news.
ALAN HAMPSON: This has shown surprisingly good responses seeing that it's a new virus where everybody expected that we might have to go to a two dose schedule to get responses.
CARLY LAIRD: But only 95 per cent of people responded positively. Is that enough?
ALAN HAMPSON: That's well within the normal limits for release of influenza vaccines; in fact we often see inferior responses to that.
CARLY LAIRD: The chief medical officer professor Jim Bishop says the next step before the rollout of the vaccine will be approval by the Therapeutic Goods Administration. He says he doesn't know how long that process will take but Alan Hampson says it could be just a matter of weeks.
ALAN HAMPSON: Look is has to go through all the normal processes of checking all the data that relates to the batches of vaccine and the standardisation of the vaccine, the testing that's been done for safety etc. So it may take another couple of weeks or so. It may even take longer. But certainly I'm sure that they will be giving it their immediate attention.
CARLY LAIRD: Professor Bishop says it's important to get a quick rollout of the vaccine even though the Australian flu season is coming to an end.
JIM BISHOP: It may come back next flu season. On the other hand it could come back at any stage through our summer and this is what's happened in the UK. And also in the US we've seen it run-on through their summer.
It may also come back at any point in a more virulent form and we've been talking about that from the beginning. We don't know whether that will occur and we certainly hope it won't.
But these are the contingencies that we must now plan for and this is the reason we think that a vaccination program, when we're ready, is the right time to roll it out, not just for next flu season.
CARLY LAIRD: Once it's approved the vaccine will first be offered to those most at risk.
JIM BISHOP: The vaccine should go to the most vulnerable, in other words the people most likely to end up in hospital or in intensive care. And these are the people with chronic underlying diseases, pregnant women. Also a higher proportion of chronic disease occurs in our Indigenous populations so Indigenous Australians would be offered the vaccine and also children in special schools.
Healthcare workers are important because of the degree of exposure that they have to these viruses.
CARLY LAIRD: Last month the Australasian Society for Infectious Diseases raised concerns about the risk of infections when using multi-dose vials in administering the vaccine but professor Bishop today said that Australia will be using multi-dose vials in line with worldwide regulations.
ELIZABETH JACKSON: Carly Laird with that report.
One Vaccine Shot Seen as Protective for Swine Flu
By DONALD G. McNEIL Jr.
Published: September 10, 2009
Defying the expectations of experts, clinical trials are showing that the new H1N1 swine flu vaccine protects with only one dose instead of two, so the vaccine supplies now being made will go twice as far as had been predicted.
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Times Topics: Swine Flu (AH1N1 Virus)
That means it should be possible to vaccinate ― well before the flu’s expected midwinter peak ― all the 159 million people that the Centers for Disease Control and Prevention estimate are in the high-risk groups: pregnant women, people under 24 years old or caring for infants, people with high-risk medical conditions and health-care workers.
Barring production delays, the government hopes to have in hand 195 million doses by year’s end.
The first convincing trial results from a single 15-microgram dose in adults were published online Thursday afternoon by The New England Journal of Medicine. That trial was done in Australia, but the vaccine maker, CSL Limited, is under contract to supply millions of doses to the United States government, and the president of the company’s American subsidiary said he expected its trials here to have similar results.
The H1N1 swine flu pandemic has now reached 168 countries. It arrived in the United States late in the spring and infected more than one million people. It did not fade out as seasonal flu does, but persisted, especially in summer camps. Nearly 600 people had died by the end of August, according to the disease control agency.
Cases are now surging again, especially in the Southeast where many schools and universities reopen earlier than in the rest of the country.
Dr. Anthony S. Fauci, director of the National Institute of Allergy and Infectious Diseases, said trials now under way under the sponsorship of the National Institutes of Health were showing that adults who got only a single dose were protected within 8 to 10 days, which he said “corroborates and confirms the exciting data” reported in the Australian study.
Robust protection produced so quickly in high-risk groups means lives will presumably be saved, Dr. Fauci said.
Costs will also be lowered by having a more efficient vaccine, he said, “but I can’t give you a dollar figure.”
Also, more vaccine could be available to poor countries that were largely left out of last spring’s global scramble to sign vaccine makers to contracts. Experts have worried that rich countries would be protected this winter while poor ones ― where people are more likely to die because of drug shortages and substandard hospital care ― would bear the brunt of the pandemic.
“This is definitely a big deal,” said Dr. John J. Treanor, a vaccine expert at the University of Rochester. “People had been planning for a scenario that would require two doses.”
“This will take the edge off the nail-biting,” Dr. Treanor added.
The results released Thursday were based on the first three weeks of a clinical trial. Healthy adults got one 15-microgram shot, and their blood was tested 21 days later. By that time, 97 percent of the 120 adults had enough antibodies to be considered protected. Another group that got 30-microgram doses had no greater protection.
There were no deaths or dangerous side-effects. Almost half of the participants reported sore arms or headaches, but that is normal with flu shots.
The American trials began about two weeks later, said Paul R. Perreault, president of CSL Biotherapies, the company’s American subsidiary. “My experience with this tells me they shouldn’t be any different,” Mr. Perreault said.
Dr. Fauci said he would discuss the details of the N.I.H. trials at a news conference on Friday afternoon.
Seasonal flu shots are available now, and Federal officials are urging Americans to get one. Little or no swine flu vaccine will be available before late October. There have been no clinical trials of giving both shots at the same time, and Federal health officials have issued no recommendations on that.
Experts had predicted for months that, because the H1N1 swine flu has never been seen before by human immune systems, it would take two doses, administered weeks apart, to get a “take” ― antibody levels as high as those produced by regular flu shots.
The authors of the Australian study said the robust response implied that there was some previously unsuspected crossover protection from having had previous strains of H1N1 seasonal flus or from the H1N1 components of seasonal flu shots.
In mid-August, a Chinese vaccine maker, Sinovac Biotech, also reported that one shot of its vaccine gave protection against the flu. But because it released no data about the size of the dose or the composition of its vaccine, it was impossible for American experts to evaluate the claim.
Also, none of the 10 Chinese companies producing swine flu vaccine have licenses to sell in the United States, as CSL does, so their vaccines would have virtually no impact on the spread of the disease here.
Although the Australian trial was in healthy adults only, Dr. Treanor said he believed one dose of the new vaccine would prove effective in everyone from age 9 and up.
Pediatricians usually give two shots to children ages 6 months to 9 years who have never had a flu shot; the first primes the immune system and subsequent shots act as boosters that create new surges of antibodies, though slightly varied each year as strains mutate.
Infants under 6 months old are not normally given flu shots. Pregnant women are, and babies can inherit some temporary immunity from their mothers.
Published at www.nejm.org September 10, 2009 (10.1056/NEJMoa0907413)
Response after One Dose of a Monovalent Influenza A (H1N1) 2009 Vaccine ― Preliminary Report
Michael E. Greenberg, M.D., M.P.H., Michael H. Lai, B.Med.Sc., M.B., B.S., M.Med.Sc., Gunter F. Hartel, M.S., Ph.D., Christine H. Wichems, Ph.D., Charmaine Gittleson, B.Sc., M.B., B.Ch., Jillian Bennet, M.Sc., M.P.H., Gail Dawson, B.Pharm., Wilson Hu, M.D., M.B.A., Connie Leggio, B.Sc., Diane Washington, M.D., and Russell L. Basser, M.B., B.S., M.D., F.R.A.C.P.
Background A novel influenza A (H1N1) 2009 virus is responsible for the first influenza pandemic in 41 years. A safe and effective vaccine is urgently needed. A randomized, observer-blind, parallel-group trial evaluating two doses of an inactivated, split-virus 2009 H1N1 vaccine in healthy adults between the ages of 18 and 64 years is ongoing at a single site in Australia.
Methods This preliminary report evaluates the immunogenicity and safety of the vaccine 21 days after the first of two scheduled doses. A total of 240 subjects, equally divided into two age groups (<50 years and ≥50 years), were enrolled and underwent randomization to receive either 15 µg or 30 µg of hemagglutinin antigen by intramuscular injection. We measured antibody titers using hemagglutination-inhibition and microneutralization assays at baseline and 21 days after vaccination. The coprimary immunogenicity end points were the proportion of subjects with antibody titers of 1:40 or more on hemagglutination-inhibition assay, the proportion of subjects with either seroconversion or a significant increase in antibody titer, and the factor increase in the geometric mean titer.
Results By day 21 after vaccination, antibody titers of 1:40 or more were observed in 116 of 120 subjects (96.7%) who received the 15-µg dose and in 112 of 120 subjects (93.3%) who received the 30-µg dose. No deaths, serious adverse events, or adverse events of special interest were reported. Local discomfort (e.g., injection-site tenderness or pain) was reported by 46.3% of subjects, and systemic symptoms (e.g., headache) by 45.0% of subjects. Nearly all events were mild to moderate in intensity.
Conclusions A single 15-µg dose of 2009 H1N1 vaccine was immunogenic in adults, with mild-to-moderate vaccine-associated reactions. (ClinicalTrials.gov number, NCT00938639 [ClinicalTrials.gov] .)
From Clinical Research and Development, CSL, Parkville, VIC, Australia.
This article (10.1056/NEJMoa0907413) was published on September 10, 2009, at NEJM.org.
Address reprint requests to Dr. Greenberg at Vaccines Clinical Research and Development, CSL, 45 Poplar Rd., Parkville, VIC 3052, Australia, or at email@example.com.
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