Dive Brief:

• Sanofi disappointed some on Wall Street with its latest look at an experimental eczema drug that the French pharmaceutical giant has pegged as a potential blockbuster.
• On Saturday, Sanofi said the drug, amlitelimab, met the primary endpoints of two late-stage studies titled COAST 1 and COAST 2. These experiments tested amlitelimab by itself, across two different dosing regimens, in patients aged 12 and older who have moderate-to-severe atopic dermatitis. After 24 weeks of treatment, amlitelimab met the main goals of both trials — which, for the U.S. and other countries where similar regulatory expectations apply, focused on the proportion of patients whose skin was deemed “clear” or “almost clear” and had improved by at least two points on a five-point scale researchers use to assess the severity of eczema.
• However, COAST 2 did not meet statistical significance on co-primary endpoints meant for the for the European Union and its reference countries. A third trial dubbed SHORE evaluated Sanofi’s drug plus topical corticosteroids and with or without topical calcineurin inhibitors. There, the drug met its endpoint after 24 weeks. Sanofi said the drug’s safety across the three studies was consistent with previous data. Yet a new case of sarcoma was reported.

Dive Insight:

While Sanofi continues to have a major presence in treating atopic dermatitis, the looming threat of Dupixent’s patent loss in 2031 has pushed the company to seek its next major prospect.

The company believes it may have that in amlitelimab. The drug, which was acquired through a $1.1 billion buyout of Kymab in 2021, targets an immune-regulating protein known as OX40L. This class of drugs has shown promise in autoimmune conditions, attracting drugmakers like Sanofi, which argues that amlitelimab can set itself apart with a less-frequent dosing schedule that could entice consumers.

However, drugs targeting OX40L have also raised safety concerns. Earlier this year, Amgen backed out of a deal to develop an eczema drug it gained the rights to from Japanese drugmaker Kyowa Kirin. While the drug, called rocatinlimab, achieved clear or nearly clear skin compared to a placebo, it was not viewed as better than Dupixent. Trial participants who took the drug also experienced a high rate of fever and chills, which could pose a commercial challenge.

Kyowa Kirin eventually abandoned the drug altogether following additional safety concerns of Kaposi’s sarcoma, a rare cancer that can cause abnormal masses on the skin that can spread to other organs.

In the results Saturday, Sanofi said the most common treatment-emergent adverse events across the trials included nasopharyngitis, atopic dermatitis, and upper respiratory tract infection. Meanwhile, the incidence of chills, pyrexia and headaches were low, as were malignancy rates.

But safety and mixed study results gave investors pause, with Leerink analyst David Risinger reducing sales projections by half. In a note to clients, he wrote the efficacy endpoints at 24 weeks in COAST-1 and COAST-2 were “weaker compared to Dupixent at 16 weeks cross-trial.”

Sanofi said its three trials have shown no severe injection site reactions, serious gastrointestinal ulceration or Kaposi’s sarcoma. The company has, though, reported two cases of Kaposi’s sarcoma in other trials, including a still-blinded Phase 3 study named ESTUARY.

Despite this, Sanofi believes the drug continues “to have the potential” as a treatment option for eczema.

The company said earlier this year it will be seeking regulatory approval for amlitelimab.