Regeneron continues reign atop the Covid treatment field with expanded EUA for lower dose subcutaneous version of mAb cocktail
The FDA on Friday authorized a new, lower-dose version of Regeneron’s Covid-19 monoclonal antibody cocktail for those with Covid-19 who are at high-risk of progressing to hospitalization.
The new dose is half the originally authorized dose, but the easier-to-administer subcutaneous version may not be the game-changer that experts once envisioned. Regeneron said in a statement that the combo “should be administered by intravenous (IV) infusion” and subcutaneous injections “are an alternative when IV infusion is not feasible and would lead to a delay in treatment.”
Regeneron spokesperson Alexandra Bowie also said the subcutaneous version will still need to be given in a health care setting (e.g. infusion center, hospital, doctor’s office) at this point, with one hour of observation required afterward.
“The presentation (the coformulated vials which were also just authorized – this just means the casirivimab and imdevimab antibodies are mixed together now vs. in separate vials) is the same for intravenous infusion or subcutaneous injection,” Bowie added.
The expanded EUA comes as Covid-19 variants emerging from India and Brazil have disrupted the delivery of some mAbs across the US, including two Eli Lilly products, a combo of bamlanivimab and etesevimab, and bamlanivimab alone, which had its EUA revoked.
Regeneron’s REGEN-COV (casirivimab and imdevimab), funded in part by BARDA, is currently the only antibody therapy available nationwide, including eight states (Arizona, California, Florida, Indiana, Oregon, Washington, Illinois and Massachusetts) with high rates of those two variants of concern.
Later this summer, Regeneron expects to submit a full BLA for the combo treatment for the same indication in non-hospitalized outpatients with Covid-19. The evaluation of REGEN-COV as a way to prevent Covid is also ongoing and the company said it submitted data to the FDA from a positive Phase III trial on the prevention of infection among household contacts of Covid-infected individuals.
As far as supplies, Regeneron expects to deliver 1 million doses by the end of this month, and the US government has pledged to purchase all doses of the mAb that are delivered by the end of this month, with the potential for more through the end of September, up to a maximum of 1.25 million doses.
That puts Regeneron at an advantage over another recently authorized mAb from Vir and GSK, which are navigating the open market without government purchases. But Vir also says its single antibody can neutralize each of the variants scientists suspect are proliferating.
And all the mAbs on the market also now benefit from a widening of who qualifies to receive them, as race or ethnicity are now included by the FDA in the eligibility criteria.
Bernstein biotech analyst Ronny Gal said in a note to investors late last month that the pause of the Lilly combo treatment will likely push the market in Regeneron’s favor. He predicts about $375 million in sales for the remainder of the year for Lilly, and about $1.6 billion in the same period for Regeneron.
As supplies are now plentiful, “it’s tough to see why any providers would take a chance on the Lilly combo,” he wrote. “We tip our hats to the Regeneron team who emphasized the importance targeting epitopes less likely to mutate from the beginning and was willing to state this view publicly.”