European Commission President Ursula von der Leyen expressed willingness to explore a waiver after President Joe Biden on Wednesday promoted the plan, reversing the U.S. position.
"The main thing is, we have to speed this up," U.S. Secretary of State Anthony Blinken said on Thursday as India battled a devastating COVID-19 outbreak. "None of us are going to be fully safe until ... we get as many people vaccinated as possible."
A patent waiver is "one possible means of increasing manufacture, and access to vaccines," he said, as the White House denied a split among officials over the waiver idea.
Biden's administration endorsed negotiations at the World Trade Organization to gain global agreement.
WTO Director-General Ngozi Okonjo-Iweala told member states that she "warmly welcomed" the U.S. move. "We need to respond urgently to COVID-19 because the world is watching and people are dying," she said.
World Health Organization (WHO) chief Tedros Adhanom Ghebreyesus reached for capital letters in a tweet calling Biden's move a "MONUMENTAL MOMENT IN THE FIGHT AGAINST #COVID19," and said it reflected "the wisdom and moral leadership of the United States."
Despite that enthusiasm, drugmakers, who stand to lose revenue if they are stripped of patent rights to COVID-19 vaccines, and other critics found flaws in the proposal.
The complexities of manufacturing means free access to the intellectual property is not enough to immediately increase vaccine production, they said. Moderna waived its patent rights in October, and on Thursday noted the lack of companies able to rapidly manufacture a similar vaccine and secure approval for it.
Combined, Pfizer Inc and Moderna Inc have forecast over $45 billion in sales this year for their COVID-19 vaccines.
In the long term, a waiver would discourage pharmaceutical companies from rapidly responding to future global health threats with large research investments, some said.
Germany, the EU's biggest economic power and home to a large pharmaceutical sector, rejected the idea, saying vaccine shortages were due to limited production capacity and quality standards rather than patent protection issues.
Health Minister Jens Spahn said he shared Biden's goal of providing the whole world with vaccines. But a government spokeswoman said in a statement that "the protection of intellectual property is a source of innovation and must remain so in the future."
Moreover, a waiver would take months to negotiate and require unanimous agreement among the 164 countries in the WTO. Drug companies urged rich countries instead to share vaccines more generously with the developing world.
DOES NOT ADDRESS 'THE REAL CHALLENGES'
Stock prices for drugmakers largely recovered after initially falling sharply after Biden backed the waiver idea. Moderna was off 1.3% after earlier dropping 12%, and the U.S. shares of its German partner BioNTech SE shed 0.6% after falling as much as 15% earlier. "The bottleneck is neither access nor patents (or price) butsimply that there aren't enough vials, raw materials, etc tomanufacture it regardless of patents," Jefferies analyst Michael Yee said of expanding COVID-19 vaccine production.
The pharmaceutical industry's main lobbying group, PhRMA, said: "This decision does nothing to address the real challenges to getting more shots in arms, including last-mile distribution and limited availability of raw materials."
There have been more than 155 million confirmed coronavirus infections worldwide and almost 3.4 million peopled have died for COVID-19, according to a Reuters tally.
But the vast bulk of the 624 million people who have received at least one dose of the vaccine, according to the Our World in Data website, live in wealthier countries.
The global COVAX vaccine distribution program, led by the WHO and the Global Alliance for Vaccines and Immunization (GAVI), that aims to supply vaccines to low-income countries, has so far handed out around 41 million doses.
French President Emmanuel Macron said he was "very much in favour" of opening up intellectual property. However, a French government official said vaccine shortages was the result of a lack of production capacity and ingredients, not of patents.
"I would remind you that it is the United States that has not exported a single dose to other countries, and is now talking about lifting the patents," the official said.
The United States has shipped a few million vaccine doses it was not using to Mexico and Canada on loan.
South Africa and India made the initial waiver proposal at the WTO in October, gathering support from many developing countries, which say it will make vaccines more widely available.
Until now, the European Union has been aligned with a group of countries, including Britain and Switzerland - home to large pharmaceutical companies - that have opposed the waiver.
(Reporting by Philip Blenkinsop and Sabine Siebold in Brussels, additional reporting by Robin Emmott, Francesco Guarascio and John Chalmers in Brussels, Emilio Parodi in Milan, Gwenaelle Barzic in Paris, Emma Farge in Geneva; Additional reporting by Trevor Hunnicutt aboard Air Force One, Andrea Shalal in Washington, Carl O'Donnell and Michelle Nichols in New York, and Ankur Banerjee in Bengaluru; Writing by Nick Macfie and Cynthia Osterman; Editing by Kevin Liffey, Mark Heinrich and Bill Berkrot)
By Philip Blenkinsop and Carl O'Donnell