Annexon, Inc. (NASDAQ: ANNX) has recently released positive topline results from a real-world evidence (RWE) study, reinforcing the potential of its anx005 therapy for the treatment of Guillain-Barré Syndrome (GBS). The RWE study compared anx005 treatment to intravenous immunoglobulin (IVIG) or plasma exchange (PE) in a matched patient cohort and produced significant findings.
The anx005-treated patients demonstrated faster and greater improvement in muscle strength and disability compared to patients in the matched cohort treated with IVIG or PE. Specifically, by week 1, patients treated with anx005 showed more than a 10-point improvement in muscle strength over patients treated with IVIG or PE. Additionally, patients treated with anx005 were approximately twice as likely to be in a better state of health than patients on IVIG or PE on the GBS-Disability Scale (GBS-DS) at multiple time points throughout the study, including at week 8, the primary endpoint for the phase 3 trial.
Furthermore, approximately half the number of patients treated with anx005 required mechanical ventilation compared with patients treated with IVIG or PE, and anx005-treated patients spent fewer days on mechanical ventilation and in the intensive care unit (ICU). These findings indicate that anx005 may decrease the overall burden of GBS care.
These positive results have led Annexon to prepare for its planned U.S. Biologics License Application submission in the first half of 2025. The company's lead investigational therapy, anx005, has received both fast track and orphan drug designations from the U.S. Food and Drug Administration, as well as orphan drug designation from the European Medicines Agency for the treatment of GBS.
The RWE study, conducted in collaboration with the International GBS Outcome Study (IGOS) investigators, applied a well-accepted statistical method of propensity score matching to establish 1:1 cohorts of patients matched on key prespecified prognostic factors of disease severity. The study cohort consisted of 79 patients in each cohort.
GBS is a severe disease resulting from an acute autoantibody and classical complement-mediated attack on peripheral nerves, and there are currently no approved treatments for GBS in the United States. The positive results from this RWE study provide hope for patients suffering from this debilitating condition and underscore the potential of anx005 as a novel targeted therapy for GBS. Today the company's shares have moved 18.2% to a price of $5.25. If you want to know more, read the company's complete 8-K report here.
