It said the request was not due to any new safety concern.
"Lilly moved quickly to make bamlanivimab alone available as a potentially lifesaving medicine at a time when Americans were hardest hit by COVID-19. With the growing prevalence of variants in the US that bamlanivimab alone may not fully neutralize, and with sufficient supply of etesevimab, we believe now is the right time to complete our planned transition and focus on the administration of these two neutralizing antibodies together,” commented Daniel Skovronsky, Lilly's chief scientific officer and president of Lilly Research Laboratories, when explaining the rationale behind the move.
All sites in the US now have access to obtain doses of etesevimab for administration with bamlanivimab—which Lilly said, together, neutralize more of the emerging COVID-19 variants in the US than bamlanivimab alone, including the rapidly growing B.1.427/B.1.429 California strain that currently accounts for 50% of the virus in California and over 10% in a number of additional US states.
“In the US, bamlanivimab alone should no longer be administered. However, sites of care should not dispose of bamlanivimab supply; instead, they should order etesevimab to pair with it,” it stressed.
Lilly's bamlanivimab was the first neutralizing monoclonal antibody to receive EUA from the FDA as a treatment for mild to moderate COVID-19. More than 400,000 US patients have been treated with it.
Bamlanivimab and/or bamlanivimab administered with etesevimab are authorized under special pathways in 20 countries outside the US spanning four continents. Both bamlanivimab alone and bamlanivimab and etesevimab together retain the neutralization effects against the vast majority of variants, including the UK variant, B.1.1.7, present in these other countries and remain an important treatment option, said Lilly.
The company is not requesting the withdrawal of emergency authorization for bamlanivimab alone in any other jurisdiction at this time. However, it said its use together with etesevimab, where authorized and available, is preferred over bamlanivimab alone.
Working in collaboration with Amgen, Lilly said it expects to manufacture sufficient supply of bamlanivimab and etesevimab together to meet global supply needs. And, going forward, it will submit only bamlanivimab administered with etesevimab together for authorization globally with a full transition expected by June 2021.
The company also said it remains committed to developing complementary neutralizing antibodies to address potential SARS-CoV-2 variants that may arise in the future.