BRUSSELS • US President Joe Biden's about-face on pushing pharmaceutical firms to share vaccine patents, in an attempt to help poorer countries, faces a considerable challenge in Europe.

Under growing pressure, the European Union said it would consider the Biden administration's decision to reverse course and support a waiver of patents for Covid-19 vaccines as many poor and middle-income nations struggle to secure lifesaving doses.

But in a speech on Thursday, European Commission president Ursula von der Leyen did not endorse the plan, raising questions about whether the bloc would agree to waive patents, something she has said she is staunchly against.

That position was underscored later in the day by a statement from Germany, the bloc's de facto leader, that the US proposal could trigger "significant implications" for the production of vaccines.

"The limiting factor in vaccine manufacturing is production capacity and high quality standards, not patents," a spokesman for German Chancellor Angela Merkel said in the statement.

In her speech, Dr von der Leyen said the EU is "ready to discuss any proposals that address the crisis in an effective and pragmatic manner". But she also suggested that the focus should instead be on getting more vaccines to countries that need them by following the bloc's example in permitting the ample export of doses.

The United States has so far baulked at that approach, keeping most doses produced domestically for use at home.

Lawyers on Thursday said that US support for waiving intellectual property (IP) rights on Covid-19 vaccines could be a tactic to convince drugmakers to back less drastic steps like sharing technology and expanding joint ventures to quickly boost global production.

"I think the end result that most players are looking for here is not IP waiver in particular, it's expanded global access to the vaccines," said Professor Lisa Ouellette of Stanford Law School.

European patent attorney Micaela Modiano said that even if the waiver is adopted, vaccine makers are likely to negotiate for some payment, if less than what is generally paid in licensing arrangements. Her firm, Modiano & Partners, represents Pfizer but has not worked on any Covid-19-related matters.

"I would imagine that the pharmaceutical companies are already and will continue to lobby significantly to make sure that if this waiver proposal passes, that it just doesn't pass as such, but that they receive some sort of financial compensation," she said.

NYTIMES, REUTERS