Annexon, Inc. (NASDAQ:ANNX) on Tuesday presented data for its late-stage targeted therapy, tanruprubart (formerly ANX005), for Guillain-Barré Syndrome (GBS).

GBS is a neuromuscular emergency affecting at least 150,000 people worldwide yearly. The rare autoimmune disease is characterized by rapidly progressing and severe weakness that can lead to complete paralysis, often requiring intensive care and mechanical ventilation.

Tanruprubart is a first-in-kind monoclonal antibody designed to block C1q, the initiating molecule of the classical complement cascade.

In the Phase 3 pivotal trial of 241 patients, tanruprubart met the primary endpoint with consistent outcomes and rapid, more complete functional recovery versus placebo across multiple time points and clinical efficacy measures.

Also Read: Mid-Cap Firm Annexon’s Nerve Disorder Candidate Shows Promise In Pivotal Late-Stage Study

The primary endpoint, GBS-Disability Scale (DS), showed that after a single infusion of tanruprubart at 30 mg/kg dose, patients had a statistically significant 2.4-fold higher likelihood of being in a better state of health than placebo at Week 8 (p=0.0058).

Highlights from the oral presentation include:

• New efficacy findings consistently demonstrated rapid recovery and durable benefits of tanruprubart across muscle strength, mobility, and disability measures:
  • At Week 1, treated patients rapidly gained motor function and were 14-fold more likely to perform the Timed Up and Go (TUG) test, a standardized measure of mobility, balance and lower limb capacity.
  • At Week 1, treated patients rapidly gained motor ability and showed more than a 2-point improvement on the Overall Neuropathy Limitation Scale (ONLS), a tool used to assess limitations in everyday activities of the upper and lower limbs
• New efficacy findings at Week 26 also demonstrated that the benefit of tanruprubart was durable, with twice the number of treated patients having no limitations on the ONLS compared to placebo.
• Treatment with tanruprubart enabled patients to walk independently and be off ventilation (for those requiring it) approximately a month earlier.
• Patients treated with tanruprubart also spent approximately a week less time in intensive care

Tanruprubart was well tolerated, with no new safety signals or off-target effects.

Price Action: ANNX stock is down 5.52% at $1.45 at the last check on Wednesday.

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This article Annexon's Investigational Drug Shows Rapid Recovery And Durable Benefit In Rare Neurological Disorder originally appeared on Benzinga.com

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