AstraZeneca's Rare Disease Drug Anselamimab Misses Primary Endpoint in Phase III AL Amyloidosis Trial, Shares Dip Slightly

Intelligent Finance APP learned that the Phase III clinical trial of AstraZeneca's (AZN.US) investigational drug Anseiramab for AL amyloidosis failed to meet the primary endpoint of extending patient survival or reducing cardiac-related hospitalizations. This result fell short of the previous expectation in the industry that critically ill patients might benefit.

According to data from the U.S. National Institutes of Health (NIH), the incidence of AL amyloidosis in the United States is approximately 12 cases per million person-years. Data from renal biopsies in China show that it accounts for 4% of patients with secondary kidney disease. The average age at diagnosis is 63 years, with a slightly higher proportion of male patients.

Despite the overall trial data falling short of expectations, Marc Dunoyer, CEO of Alexion, AstraZeneca's rare disease division, emphasized positive treatment responses observed in certain patient groups. The company is conducting an in-depth analysis of the trial details to uncover potential value. As the first fibril-depleting agent to demonstrate clinical benefits in AL amyloidosis, Ansevimab innovatively eliminates organ deposits by specifically binding to misfolded light chain fibrils.

Currently, the treatment of AL amyloidosis mainly relies on CD38 monoclonal antibodies such as Daratumumab. The phase III ANDROMEDA study showed that the combination of Daratumumab with chemotherapy (D-VCd) increased the complete response rate (CR) to 59.5%, with cardiac and renal response rates reaching 53% and 58%, respectively, significantly better than traditional chemotherapy. However, existing therapies still have limitations: only about 20% of patients are eligible for autologous hematopoietic stem cell transplantation, proteasome inhibitors have limited efficacy in advanced patients, and alkylating agents and immunomodulatory drugs present safety concerns.

Affected by the trial results, AstraZeneca's share price fell 0.61% during pre-market trading, closing at $69.89, with a total market value of $218 billion. Although the main results did not meet expectations, the drug’s efficacy in some patients and its breakthrough mechanism of action are still regarded as positive signals. Medical experts pointed out that the partial success of Anselamab provides direction for subsequent precision treatments, especially for advanced patient groups who respond poorly to existing therapies.

The competition for new drug development in the field of AL amyloidosis is intense. In addition to Anslemimab, CAEL-101 has shown potential in clearing organ amyloid deposits in Phase II trials, with a 1-year overall survival rate of 93% when combined with chemotherapy, but a cardiac response rate of only 27% (6/22 cases), requiring further verification in Phase III trials. The antibody-drug conjugate Belantamab mafodotin achieved ≥PR in 70% of patients in early AL amyloidosis trials, but its expanded indications still require large-scale data support. Additionally, fibril-targeting drugs such as NEOD001 were discontinued due to efficacy not meeting expectations, highlighting the 'high-risk, high-reward' nature of research and development in this field.

AstraZeneca stated that it will continue to advance the data analysis of Anselemab and explore its applicability in a more precise patient population. With a deeper understanding of disease mechanisms, fibril-depleting agents are expected to create synergistic effects with existing therapies, further improving patient outcomes.