Lilly's Alzheimer's Drug Faces Setback in Europe, Mirroring Earlier Challenges for Eisai and Biogen

Eli Lilly's promising Alzheimer's treatment, Kisunla, has encountered a significant hurdle in its quest for European market approval, echoing similar challenges faced by competitors Eisai and Biogen. The European Medicines Agency (EMA) has recommended against granting marketing authorization for Kisunla, citing concerns that its benefits do not outweigh potential risks.

EMA's Concerns and Lilly's Response

The EMA's decision primarily stems from safety concerns related to ARIA (Amyloid-Related Imaging Abnormalities), a side effect characterized by brain swelling and small-scale bleeding. In clinical trials, 36.8% of patients receiving Kisunla experienced ARIA, compared to 14.9% in the placebo group. This significant difference has raised red flags for European regulators.

Despite this setback, Lilly remains confident in Kisunla's safety and efficacy profile. Ilya Yuffa, president of Lilly International, stated, "We hope that through the re-examination process, we will be able to continue our discussions with the agency to bring [the drug] to the millions of people across Europe suffering from this relentless, fatal disease."

Lilly plans to appeal the EMA's decision, a strategy that proved successful for Eisai and Biogen's Leqembi last year. However, analysts from RBC Capital Markets note that over the past decade, the EMA has only reversed its initial opinion in about 20% of cases.

Clinical Efficacy and Market Implications

Kisunla has demonstrated modest but meaningful efficacy in clinical trials, with patients experiencing a 20% to 30% slowing of disease progression compared to placebo. This level of efficacy is similar to that of other drugs in its class, including Leqembi.

The European market represents a significant opportunity for Alzheimer's treatments, with an estimated 7 million people living with the disease. Analysts at William Blair project peak sales for Leqembi in Europe to reach $1.3 billion by 2031, underscoring the potential commercial impact of these new therapies.

While Kisunla has already gained approval in the United States, United Kingdom, China, and Japan, Europe remains a crucial market. Lilly reported $8 million in Kisunla sales for the last quarter of the previous year, highlighting the drug's early commercial traction.

As the appeal process unfolds, the pharmaceutical industry will be watching closely to see if Lilly can overcome this regulatory hurdle and bring Kisunla to European patients in need of new treatment options for Alzheimer's disease.