Gates, UK take lead in $7.5 bln pledge for children's vaccines

* Vaccine alliance hopes to immunise 300 million children

* Gates donates $1.55 bln, wants to halve child deaths

* GAVI buys vaccines in bulk for poor countries (Adds details, quotes and reactions)

By Stephen Brown

BERLIN, Jan 27 (Reuters) - International donors pledged $7.5 billion on Tuesday to immunise 300 million children in poor countries against deadly diseases such as diarrhoea and pneumonia.

At a Global Alliance for Vaccines and Immunisation (GAVI) conference in Berlin, Microsoft (NasdaqGS: MSFT - news) founder Bill Gates and the British government topped the donations list at $1.55 billion and $1.5 billion respectively.

German development minister Gerd Mueller said the total reached $7.54 billion, surpassing GAVI's target of $7.5 billion, despite a stronger dollar complicating funding efforts.

Other major donors included the United States, Norway and Germany. China, a recipient of GAVI assistance early last decade, has now become a donor.

"It was a bold ask to world leaders but also a very compelling case," said GAVI chairman Dagfinn Hoybraten. "In the course of five years from 2016 to 2020 we could vaccinate another 300 million children and avert 5-6 million future deaths."

Gates, who has donated $4 billion to GAVI since it began 15 years ago, said there had been "amazing" progress but one in 20 children still died before their fifth birthday.

"The goal for the next 15 years is to cut that in half again to get it to one in 40," he said.

GAVI has provided vaccines to about 500 million children worldwide and saved 6-7 million lives from diseases like pneumonia, hepatitis B, diarrhoea and measles, working with the World Health Organisation, UNICEF, World Bank and charities.

Michael Elliott of anti-poverty group One, calling GAVI a way for rich countries to give "an infinitesimal part of their tax money to save lives".

But Save the Children's Jasmine Whitbread said the problems were still huge: "In some of the world's poorest communities only 16 percent of children are reached by vaccines."

GAVI funds immunisation for countries that cannot afford them, using its buying power to negotiate discounts from the likes of GlaxoSmithKline (Other OTC: GLAXF - news) and Pfizer (NYSE: PFE - news) . Medical charity Medecins Sans Frontieres argues that it should strike even tougher deals.

Pfizer has said it would cut pneumococcal vaccine prices by 6 percent for poor countries through 2025, including those that outgrow their eligibility for GAVI. GlaxoSmithKline has extended its price-freeze commitment to 10 years for countries graduating from GAVI and Sanofi (NasdaqGM: GCVRZ - news) will expand production of yellow fever vaccine.

But GAVI's CEO Seth Berkley called the latest discount for pneumococcal vaccine "small" and said he hoped new manufacturers would emerge to help bring about bigger price reductions. (Editing by Ben Hirschler and Robin Pomeroy)