(corrects final para to say Relenza known generically as zanamivir, not oseltamivir)
* WHO to send 2.4 million Tamiflu courses to 72 countries
* Swiss drugmaker Roche donated rapid response stockpile
GENEVA, May 5 (Reuters) - The World Health Organisation said on Tuesday it would begin sending 2.4 million treatment courses of Tamiflu, an antiviral proven effective against the new flu, to 72 countries deemed in need, including Mexico.
The Swiss drugmaker Roche Holding AG donated the stockpiles to the United Nations agency several years ago for use in a possible influenza pandemic.
"The WHO is dispatching 2.4 million courses of antivirals to 72 countries most in need, including Mexico," WHO spokeswoman Fadela Chaib told a news briefing in Geneva.
"Part of the stock will be dispatched today (Tuesday)."
Shipments will be made from "three hubs" -- Switzerland, Maryland, in the United States, and Dubai in the United Arab Emirates, she said.
The WHO will also supplement its regional stockpiles in its six regions for "contingency" use in countries which may suffer outbreaks of the new H1N1 virus, according to Chaib.
Roche said on Saturday the WHO had asked it to deploy its so-called rapid response stockpiles and that it was also increasing production to meet rising demand.
GlaxoSmithKline, the world's second largest drugmaker, said last Friday it was increasing production of Relenza, a flu drug which must be inhaled.
Tamiflu and Relenza, known generically as oseltamivir and zanamivir respectively, are the only two approved drugs to which the new strain of influenza A H1N1 has been found to be susceptible. (Reporting by Stephanie Nebehay; Editing by Michael Kahn and Jon Hemming)