The first human trials of a swine- flu vaccine are set to begin in Australia tomorrow as deaths and infections from the H1N1 virus mount worldwide, intensifying demand for a protective shot.swine-flu-vaccine

CSL Ltd., the only flu-vaccine maker in the Southern Hemisphere, plans to start the research today in Adelaide by injecting a group of healthy volunteers with its experimental vaccine, the Melbourne-based company said July 14. CSL plans to test the shot in 240 people, ages 18 to 64, during the next seven weeks in preparation for filling orders from Australia, the U.S. and Singapore.

The World Health Organization and CSL’s larger rivals, including Sanofi-Aventis SA, will be watching the shot to determine how much antigen — the key substance in vaccines –is needed to prevent people from getting infected. The results will help makers decide how many shots can be produced and how many people vaccinated.

“The world will be watching to see the immunogenicity results of this first clinical trial,” Marie-Paule Kieny, director of the Geneva-based WHO’s initiative for vaccine research, said by e-mail. “It is likely to be indicative of how the other vaccine candidates will perform.”

Swine flu, known as A(H1N1), has sickened so many people worldwide that the WHO has advised health authorities to stop testing suspected cases and report only hospitalizations. How much vaccine can be produced, how fast, and how effective it will prove to be are still unknown as the pandemic virus spreads.

Hundreds of Deaths

A total of 94,512 laboratory-confirmed cases of the swine flu, resulting in 429 deaths, had been counted as July 6, according to figures released by the WHO before it stopped issuing tables showing cases in all countries with the virus.

Health-care workers are the “main priority group” to get the shot when it becomes available, the WHO said on July 13. Individual countries should decide on priority when inoculating other groups such as children and the elderly, the United Nations agency said.

There isn’t any commercial advantage to being the first vaccine maker to start human trials, as most manufacturers already have orders to supply vaccines to governments, said David Low, a health-care analyst at Deutsche Bank AG in Sydney.

“Being first is probably more of a PR coup,” Low said in a telephone interview on July 16.

CSL may record sales of A$300 million ($239 million) this year for its swine-flu vaccine, said Alexander Smith, a health- care analyst at JPMorgan Chase & Co. in Sydney.

‘Sounds Reasonable’

“That sounds reasonable,” said Rachel David, a CSL spokeswoman.

Two shots of vaccine will probably be needed to protect people against the pandemic virus, said Michael Osterholm, director of the Center for Infectious Disease Research and Policy, at the University of Minnesota in Minneapolis.

CSL has a contract to supply 21 million doses to Australia’s government, David said. It also has an order from the U.S. for $180 million of antigen, enough for 20 million to 40 million doses, depending on the results of trials, she said. The company also has an order from Singapore, David said, declining to give details.

Novartis AG expects to start trials of its shot this month, Eric Althoff, a spokesman for the Basel, Switzerland-based drugmaker, said in a July 14 e-mail, without giving a date. Sanofi plans to start tests of its shot in August, Albert Garcia, a spokesman for the Paris-based company’s vaccines unit, said in a phone interview on July 16.

Glaxo, Baxter

David Outhwaite, a spokesman for GlaxoSmithKline Plc, declined to answer questions about the London-based drugmaker’s plans to test its shot.

Baxter International Inc., based in Deerfield, Illinois, will produce a vaccine by early August, after which the company will perform clinical testing, said Chris Bona, a company spokesman.

The U.S. Centers for Disease Control and Prevention, based in Atlanta, has said it expects a vaccine ready for widespread distribution in October.

Sinovac Biotech Ltd., a Beijing-based flu-vaccine maker, expects to complete production of the first batch of its shot by the end of this month and start trials after that, Helen Yang, a company spokeswoman, said in an e-mail.

CSL will give each volunteer two shots, three weeks apart, to determine how many doses are needed to get the right immune response, David said. CSL is also testing the CSL425 vaccine, known as Panvax (H1N1 A/California) in Australia, in two dose sizes to see which is more effective, she said.

The company is conducting the trials through CMAX, the clinical research unit of IDT Australia Ltd. — Bloomberg