Annexon Highlights Pivotal Data on First Potential Targeted Therapy for Guillain-Barré Syndrome (GBS) and Showcases New GBS Education Campaign at American Academy of Neurology (AAN) 2025 Annual Meeting
Annexon (NASDAQ: ANNX) presented pivotal Phase 3 data for tanruprubart, a potential first targeted therapy for Guillain-Barré Syndrome (GBS), at the AAN 2025 Annual Meeting. The trial of 241 patients demonstrated that a single infusion of tanruprubart led to 2.4-fold higher likelihood of improved health versus placebo at Week 8.
Key findings include: patients showed 14-fold higher mobility at Week 1, twice the number of treated patients had no limitations at Week 26, and patients recovered approximately one month earlier than placebo group. The treatment reduced intensive care time by about a week. A Real World Evidence study comparing tanruprubart with standard treatments (IVIg/PE) showed superior muscle strength recovery.
GBS affects 150,000 people worldwide annually, with no FDA-approved therapies. Annexon also launched the Move GBS Forward™ education campaign to increase disease awareness among healthcare professionals.
Annexon (NASDAQ: ANNX) ha presentato dati cruciali della Fase 3 per tanruprubart, una potenziale prima terapia mirata per la Sindrome di Guillain-Barré (GBS), durante l'Annual Meeting AAN 2025. Lo studio, che ha coinvolto 241 pazienti, ha dimostrato che un'unica infusione di tanruprubart ha portato a una probabilità 2,4 volte maggiore di miglioramento della salute rispetto al placebo alla Settimana 8.
I risultati principali includono: i pazienti hanno mostrato una mobilità 14 volte superiore alla Settimana 1, il doppio dei pazienti trattati non ha presentato limitazioni alla Settimana 26 e i pazienti si sono ripresi circa un mese prima rispetto al gruppo placebo. Il trattamento ha ridotto il tempo di ricovero in terapia intensiva di circa una settimana. Uno studio di Evidenza del Mondo Reale che confronta tanruprubart con i trattamenti standard (IVIg/PE) ha mostrato un recupero della forza muscolare superiore.
La GBS colpisce 150.000 persone in tutto il mondo ogni anno, senza terapie approvate dalla FDA. Annexon ha anche lanciato la campagna educativa Move GBS Forward™ per aumentare la consapevolezza sulla malattia tra i professionisti della salute.
Annexon (NASDAQ: ANNX) presentó datos clave de la Fase 3 para tanruprubart, una posible primera terapia dirigida para el Síndrome de Guillain-Barré (GBS), en la Reunión Anual AAN 2025. El ensayo, que incluyó a 241 pacientes, demostró que una única infusión de tanruprubart llevó a una probabilidad 2.4 veces mayor de mejora en la salud en comparación con el placebo a la Semana 8.
Los hallazgos clave incluyen: los pacientes mostraron 14 veces más movilidad en la Semana 1, el doble de pacientes tratados no tuvieron limitaciones en la Semana 26 y los pacientes se recuperaron aproximadamente un mes antes que el grupo placebo. El tratamiento redujo el tiempo en cuidados intensivos en aproximadamente una semana. Un estudio de Evidencia del Mundo Real que compara tanruprubart con tratamientos estándar (IVIg/PE) mostró una recuperación de fuerza muscular superior.
El GBS afecta a 150,000 personas en todo el mundo anualmente, sin terapias aprobadas por la FDA. Annexon también lanzó la campaña educativa Move GBS Forward™ para aumentar la concienciación sobre la enfermedad entre los profesionales de la salud.
Annexon (NASDAQ: ANNX)은 AAN 2025 연례 회의에서 길랭-바레 증후군(GBS)을 위한 잠재적 첫 번째 표적 치료제인 탄루프루바르트(tanruprubart)의 중요한 3상 데이터를 발표했습니다. 241명의 환자를 대상으로 한 이 시험에서 탄루프루바르트의 단일 주입이 8주차에 위약 대비 2.4배 높은 건강 개선 가능성을 나타냈습니다.
주요 발견 사항은 다음과 같습니다: 환자들은 1주차에 14배 더 높은 이동성을 보였고, 치료받은 환자의 두 배가 26주차에 제한이 없었으며, 환자들은 위약 그룹보다 약 한 달 더 빨리 회복되었습니다. 이 치료는 집중 치료 시간을 약 일주일 줄였습니다. 탄루프루바르트를 표준 치료(IVIg/PE)와 비교한 실제 증거 연구에서는 근력 회복이 우수하다는 결과가 나타났습니다.
GBS는 매년 전 세계적으로 150,000명에게 영향을 미치며, FDA 승인 치료제가 없습니다. Annexon은 또한 의료 전문가들 사이에서 질병 인식을 높이기 위해 Move GBS Forward™ 교육 캠페인을 시작했습니다.
Annexon (NASDAQ: ANNX) a présenté des données clés de la phase 3 pour tanruprubart, une potentielle première thérapie ciblée pour le syndrome de Guillain-Barré (GBS), lors de la réunion annuelle de l'AAN 2025. L'essai, qui a impliqué 241 patients, a démontré qu'une seule infusion de tanruprubart a conduit à une probabilité 2,4 fois plus élevée d'amélioration de la santé par rapport au placebo à la semaine 8.
Les principales conclusions incluent : les patients ont montré une mobilité 14 fois plus élevée à la semaine 1, deux fois plus de patients traités n'avaient aucune limitation à la semaine 26, et les patients se sont rétablis environ un mois plus tôt que le groupe placebo. Le traitement a réduit le temps en soins intensifs d'environ une semaine. Une étude sur les preuves du monde réel comparant tanruprubart à des traitements standards (IVIg/PE) a montré une récupération de force musculaire supérieure.
Le GBS touche 150 000 personnes dans le monde chaque année, sans thérapies approuvées par la FDA. Annexon a également lancé la campagne éducative Move GBS Forward™ pour sensibiliser les professionnels de la santé à la maladie.
Annexon (NASDAQ: ANNX) präsentierte auf dem AAN 2025 Jahresmeeting entscheidende Phase-3-Daten zu tanruprubart, einer potenziellen ersten zielgerichteten Therapie für das Guillain-Barré-Syndrom (GBS). Die Studie mit 241 Patienten zeigte, dass eine einzelne Infusion von tanruprubart zu einer 2,4-fach höheren Wahrscheinlichkeit für eine Verbesserung der Gesundheit im Vergleich zur Placebo-Gruppe in Woche 8 führte.
Wichtige Ergebnisse sind: Die Patienten zeigten in Woche 1 eine 14-fach höhere Mobilität, doppelt so viele behandelte Patienten hatten in Woche 26 keine Einschränkungen und die Patienten erholten sich etwa einen Monat früher als die Placebo-Gruppe. Die Behandlung reduzierte die Zeit auf der Intensivstation um etwa eine Woche. Eine Real-World-Evidence-Studie, die tanruprubart mit Standardbehandlungen (IVIg/PE) verglich, zeigte eine überlegene Wiederherstellung der Muskelkraft.
GBS betrifft jährlich 150.000 Menschen weltweit, ohne von der FDA zugelassene Therapien. Annexon startete auch die Bildungsinitiative Move GBS Forward™, um das Bewusstsein für die Krankheit unter Gesundheitsfachkräften zu erhöhen.
- Phase 3 trial met primary endpoint with 2.4-fold higher likelihood of better health vs placebo
- Demonstrated 14-fold improvement in mobility at Week 1
- Twice the number of treated patients achieved full recovery at Week 26
- Reduced intensive care time by approximately one week
- Superior efficacy compared to current standard treatments in Real World Evidence study
- Well-tolerated safety profile with no new safety signals
- None.
Insights
Annexon's Phase 3 data for tanruprubart (formerly ANX005) in Guillain-Barré Syndrome (GBS) represents a significant clinical breakthrough in a disease with no FDA-approved therapies. The results are compelling across multiple dimensions:
The therapy demonstrated statistical significance on the primary endpoint with patients 2.4-fold more likely to be in a better health state than placebo at Week 8 (p=0.0058). What's particularly impressive is the rapid onset of action - at just Week 1, treated patients were 14-fold more likely to perform mobility tests and showed substantial improvements in everyday activity limitations.
The durability of benefits is equally noteworthy, with twice as many tanruprubart-treated patients achieving full recovery at Week 26 compared to placebo. The concrete clinical outcomes - patients walking independently and coming off ventilation a month earlier, plus approximately one week less ICU time - translate to meaningful quality-of-life improvements and potential healthcare cost reductions.
The consistent efficacy across multiple endpoints (GBS-DS, ONLS, TUG test) coupled with a favorable safety profile strengthens the regulatory case. The complementary Real World Evidence study showing advantages over current standard treatments (IVIg/PE) further validates tanruprubart's clinical differentiation.
For a rare disease affecting 150,000 patients globally each year, this represents potentially the first targeted therapy designed to halt the underlying neuroinflammation and nerve damage driving GBS progression.
Annexon's Phase 3 results for tanruprubart represent a significant value inflection point for the company. The data package is remarkably robust - meeting the primary endpoint with statistical significance (p=0.0058) and demonstrating consistent benefits across multiple clinically relevant secondary measures.
Three elements particularly stand out from an investment perspective: First, the competitive landscape is wide open with no FDA-approved therapies for GBS, positioning Annexon for potential first-mover advantage in this market. Second, the multiple mechanisms of benefit (faster recovery, more complete recovery, reduced ICU time) create a compelling value proposition for payers. Third, the clean safety profile removes a major regulatory risk factor.
The company's simultaneous launch of the Move GBS Forward™ education campaign strategically lays groundwork for eventual commercialization by increasing disease awareness among healthcare providers. This preparation for market entry demonstrates forward-thinking management.
The Real World Evidence study comparing tanruprubart to current standard care (IVIg/PE) provides critical differentiation data that will be essential for both regulatory submissions and eventual market adoption. With GBS affecting 150,000 patients annually worldwide and representing a neuromuscular emergency, this therapy addresses a genuine unmet medical need with significant market potential.
These results substantially de-risk Annexon's lead program and strengthen the company's position for either commercialization or potential partnership discussions.
Oral Presentation Features Phase 3 Data Showing Rapid Recovery and Durable Benefit of Tanruprubart (formerly ANX005) on Clinically Meaningful Measures across Multiple Stages of GBS
Disease Education Campaign for Healthcare Providers called Move GBS Forward™ (MoveGBSForward.com) Highlights
Life-altering Impact of GBS
BRISBANE, Calif., April 08, 2025 (GLOBE NEWSWIRE) -- Annexon, Inc. (Nasdaq: ANNX), a biopharmaceutical company advancing a late-stage clinical platform of novel therapies for people living with devastating classical complement-mediated neuroinflammatory diseases of the body, brain, and eye, today presented data for its late-stage targeted therapy for GBS and showcased new disease education activities at the AAN Annual Meeting taking place April 5–9, 2025, in San Diego, California. An oral presentation today during the “Clinical Trials Plenary” session featured results of the tanruprubart (formerly ANX005) Phase 3 placebo-controlled trial reinforcing its rapid and durable clinical benefits for patients with GBS. A replay of the session is available to AAN registrants.
GBS is a neuromuscular emergency that affects at least 150,000 people worldwide each year, with no FDA-approved therapies. 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. With a single infusion, tanruprubart halts ongoing neuroinflammation and nerve damage in the acute phase of GBS to improve and expedite overall recovery.
"After decades without any advancement in treatment or care, there is an urgent need for therapies that work quickly and effectively to treat GBS. Tanruprubart is an exciting and novel therapy that has shown a rapid and durable biological effect that shuts down neuroinflammation and nerve damage, potentially stopping the disease in its tracks,” said Jeff Allen, M.D., Professor of Neurology, University of Minnesota. “The results of this Phase 3 placebo-controlled study, combined with a real-world study of GBS patients treated with standard therapies underscores the benefits of rapidly blocking neuroinflammation. Tanruprubart has the potential to help patients get better faster and ultimately reach a better state of health than with existing therapies or without treatment, while significantly reducing the burden of care."
First Placebo-Controlled Phase 3 Trial for GBS Presented in AAN Oral Presentation
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. 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 at AAN 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
- 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
- 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
- The new findings build upon previously reported Phase 3 trial results that showed an improvement in the primary endpoint of GBS-DS at Week 8, as well as that twice the number of patients treated with tanruprubart fully recovered to normal (GBS-DS = 0) at Week 26, 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
Results of the Phase 3 trial are reinforced by a Real World Evidence (RWE) study that matched tanruprubart-treated patients from the pivotal Phase 3 study with a Western world patient population treated with current standards of care, intravenous immunoglobulin (IVIg) or plasma exchange (PE). In the RWE study, tanruprubart showed a rapid increase in muscle strength with more complete recovery over IVIg or PE, consistent with benefits shown in the Phase 3 trial. The RWE study is planned for presentation at upcoming conferences.
Disease Education Campaign Aims to Move Understanding of GBS Forward
Annexon also announced a new education campaign for healthcare professionals called Move GBS Forward™, which is designed to advance awareness and understanding of the sudden and long-term impact of GBS to encourage prompt diagnosis and care. Featuring the striking image of a patient frozen in ice with the header “Guillain-Barré Syndrome can trap your patients for a lifetime,” the campaign draws attention to the life-altering physical and mental consequences of GBS. The campaign website address is MoveGBSForward.com.
“As a rare disease, GBS is often misunderstood and misdiagnosed contributing to the trauma that patients suffer as they experience the severe weakness and acute paralysis caused by nerve damage,” said Lisa Butler, President and CEO at the GBS/CIDP Foundation International. “This new education campaign reflects the patient experience and feelings of being trapped. It will help get GBS on the map for many more healthcare providers, so that the GBS community can take a step forward towards a future where patients may have a quicker recovery and better outcomes.”
Additionally, Annexon supported a symposium at AAN titled “Advancing GBS Care: Latest Insights into the role of classical complement pathway in GBS” where experts discussed the current state of patient care and need for new targeted treatments.
About Guillain-Barré Syndrome
GBS is a rare neuromuscular emergency resulting from an acute autoantibody and classical complement-mediated attack on peripheral nerves that generally occurs post-infection in otherwise healthy persons. It is an acute, rapidly progressive disease with a narrow timeframe for therapeutic intervention. GBS results in the hospitalization of more than 22,000 people annually in the U.S. and Europe. The peripheral nerve damage progresses rapidly, causing acute neuromuscular paralysis that can lead to significant morbidity, disability and mortality. Currently, there are no approved treatments for GBS in the United States. The long-term disease burden associated with GBS has led to a multi-billion-dollar annual economic cost to the U.S. healthcare system alone. More information about the impact of GBS is available at MoveGBSForward.com.
About Annexon
Annexon Biosciences (Nasdaq: ANNX) is developing therapeutics that stop classical complement-driven neurodegeneration as first-in-kind treatments for millions of people living with serious neuroinflammatory diseases of the body, brain and eye. Our novel scientific approach focuses on C1q, the initiating molecule of classical complement’s potent inflammatory pathway that when misdirected can lead to tissue damage and loss. By targeting C1q, our immunotherapies are designed to stop this neuroinflammatory cascade in disease before it starts. Our pipeline spans three diverse therapeutic areas – autoimmune, neurodegenerative and ophthalmic diseases – and includes targeted investigational drug candidates designed to address the unmet needs of over 8 million people worldwide. Annexon’s mission is to deliver game-changing therapies to patients so that they can live their best lives. To learn more visit annexonbio.com.
Forward Looking Statements
This press release contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. In some cases, you can identify forward-looking statements by terminology such as “aim,” “anticipate,” “assume,” “contemplate,” “continue,” “could,” “design,” “due,” “estimate,” “expect,” “goal,” “intend,” “may,” “objective,” “plan,” “positioned,” “potential,” “predict,” “seek,” “should,” “target,” “will,” “would” and other similar expressions that are predictions of or indicate future events and future trends, or the negative of these terms or other comparable terminology. All statements other than statements of historical facts contained in this press release are forward-looking statements. These forward-looking statements include, but are not limited to, statements about: the ability of ANX005 to block C1q activity within a single infusion; the potential therapeutic benefit of ANX005, if approved, compared to IVIg/plasma exchange or existing therapies; the planned presentation of RWE at upcoming conferences; the ability to translate the results of the RWE study to a broad population of GBS patients; the impacts of the new education campaign (Move GBS Forward™); the potential benefits from treatment with anti-C1q therapy; and continuing advancement of the company’s portfolio. Forward-looking statements are not guarantees of future performance and are subject to risks and uncertainties that could cause actual results and events to differ materially from those anticipated, including, but not limited to, risks and uncertainties related to: the company’s history of net operating losses; the company’s ability to obtain necessary capital to fund its clinical programs; the early stages of clinical development of the company’s product candidates; the effects of public health crises on the company’s clinical programs and business operations; the company’s ability to obtain regulatory approval of and successfully commercialize its product candidates; any undesirable side effects or other properties of the company’s product candidates; the company’s reliance on third-party suppliers and manufacturers; the outcomes of any future collaboration agreements; and the company’s ability to adequately maintain intellectual property rights for its product candidates. These and other risks are described in greater detail under the section titled “Risk Factors” contained in the company’s Annual Report on Form 10-K and Quarterly Reports on Form 10-Q and the company’s other filings with the SEC. Any forward-looking statements that the company makes in this press release are made pursuant to the Private Securities Litigation Reform Act of 1995, as amended, and speak only as of the date of this press release. Except as required by law, the company undertakes no obligation to publicly update any forward-looking statements, whether as a result of new information, future events or otherwise.
Investor Contact:
Joyce Allaire
LifeSci Advisors
jallaire@lifesciadvisors.com
Media Contact:
Sheryl Seapy
Real Chemistry
949-903-4750
sseapy@realchemistry.com
FAQ
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