Regeneron/Sanofi's antibody underwhelms in asthma study — shares of rival AnaptysBio pay the price
Although expectations were muted, Regeneron $REGN and Sanofi’s $SNY experimental IL-33 antibody has underwhelmed in a proof-of-concept mid-stage asthma trial. Although the drug significantly improved the loss of asthma control and lung function as a monotherapy compared to a placebo, its effect was neither superior to the established Dupixent, nor of value when combined with the IL-4/IL-13 treatment.
The drug, REGN3500, was tested in a trial involving 296 adult patients with moderate-to-severe asthma, whose disease was not controlled with standard-of-care treatment with inhaled corticosteroid (ICS) and long-acting beta-agonist (LABA) therapy. Patients were randomized into four treatment groups: REGN3500 plus placebo, REGN3500 plus Dupixent, Dupixent plus placebo, and placebo.
In the trial, patients treated with Dupixent monotherapy performed numerically better than REGN3500 across all endpoints, although the trial was not powered to show differences between active treatment arms. In addition, the combination of REGN3500 and Dupixent also did not demonstrate increased benefit compared to Dupixent monotherapy in this trial, Regeneron said. Detailed results will be presented later.
“We don’t believe REGN3500 will contribute meaningful value to Regeneron’s asthma franchise,” Credit Suisse analysts wrote in a note.
Shares of AnaptysBio $ANAB, which is developing its own IL-33 antibody called etokimab, tumbled about 15% before the bell to $57.40.
Analysts were divided on the REGN3500’s readthrough to etokimab, which is being developed for similar indications.
On one hand, Stifel analysts published a note suggesting they were not confident that etokimab “will be meaningfully differentiated from SNY/REGN’s Dupixent, which we think is required for the stock to work.”
But Jefferies analysts saw a silver lining. “The biggest threat to ANAB’s etokimab has been the prospects of the combo arm, and given its demise, we view the data as a positive for etokimab,” they wrote in a note titled “Don’t Throw The Baby Out With Bathwater.”
“While critics will point to ‘3500s numerical inferiority as evidence that etokimab may not offer anything, we differ, and do not believe all monoclonal antibodies are built to perform in the same manner. We point to AMG-317 failing in asthma, and targets IL-4, and yet Dupixent has seen success.”
Dupixent, which apart from asthma is also approved for eczema, generated first quarter sales of nearly $374 million.