Otsuka Opens Global Early Access Program for Ulefnersen in FUS-ALS
核心洞察
Otsuka Pharmaceutical Development & Commercialization (搜索) has initiated a global early access program for ulefnersen, an investigational antisense oligonucleotide for FUS-ALS (搜索), announced September 22, 2026.
The program targets patients with a confirmed genetic diagnosis of FUS-ALS (搜索) who cannot enroll in an ongoing clinical trial and meet predefined eligibility criteria.
Ulefnersen binds FUS pre-mRNA to reduce FUS protein (搜索) production and is given by intrathecal injection; it remains unapproved worldwide and is being studied in the Phase 1-3 FUSION trial.
Otsuka Pharmaceutical Development & Commercialization (搜索), Inc. announced on September 22, 2026 the initiation of a global early access program (EAP) for ulefnersen, an investigational antisense oligonucleotide, in eligible people living with FUS-ALS (搜索), a genetic subtype of amyotrophic lateral sclerosis (搜索) caused by mutations in the fused in sarcoma (FUS) gene.
The program is intended for individuals with a confirmed genetic diagnosis of FUS-ALS (搜索) who are unable to participate in an ongoing clinical trial and who meet other predefined eligibility criteria. Otsuka said the EAP reflects its commitment to facilitate early access to investigational medicines outside of a clinical trial, where permitted by local regulations, for people living with rare and life-threatening conditions who have limited or no available treatment options.
Ulefnersen has not been approved by the U.S. Food and Drug Administration (搜索) or any regulatory authority worldwide.
Program Mechanics and Physician-Led Applications
Otsuka cannot accept direct requests for EAP access from patients or carers. All requests must be initiated by a treating physician on behalf of the person living with FUS-ALS (搜索). Following review and potential acceptance of an application, additional steps are required before treatment can begin, which may include applicable regulatory and ethics approvals, treatment-center readiness and patient-specific requirements. Timing from application to treatment will vary based on these factors.
Program availability, eligibility criteria and application processes may vary by country and evolve over time. Treating physicians seeking information about eligibility criteria, or who wish to apply, should visit the Otsuka Early Access Portal.
"Our approach to early access for ulefnersen is guided by an assessment of the available clinical evidence and our commitment to patient safety," said John Kraus, M.D., Ph.D., executive vice president and chief medical officer, Otsuka. "For people living with FUS-ALS (搜索), their families, carers and advocates, decisions about treatment are deeply personal. This program is built on a foundation of safety, transparency and trust, with the goal of supporting informed decisions between eligible patients and their healthcare providers."
Disease Burden in FUS-ALS
FUS-ALS (搜索) occurs across a broad age range, including pediatric and juvenile patients, and is often rapidly progressive. It represents an estimated 0.6% of all ALS cases. FUS mutations are more prevalent in juvenile and pediatric ALS, accounting for an estimated 43 to 52% of cases. These mutations lead to accumulation of toxic FUS protein (搜索) in motor neurons, driving neurodegeneration.
The disease progresses by eroding muscle function, affecting patients' independence as they lose the ability to move, speak, swallow and breathe, ultimately leading to premature death. In early-onset and juvenile cases, progression can lead to respiratory failure and death, often within 1 to 2 years of symptom onset. Diagnosis generally requires specialized clinical evaluation and confirmatory genetic testing.
There are currently no approved therapies specifically targeting the underlying genetic cause of FUS-ALS (搜索).
Mechanism and Development Status
Ulefnersen is an RNA-targeted medicine designed to bind FUS pre-messenger RNA (pre-mRNA) and reduce production of FUS protein (搜索) in people with FUS-ALS (搜索). Through reduction of FUS mRNA levels, the drug is intended to decrease production of FUS protein, including the mutant forms that contribute to motor neuron degeneration. It is administered via intrathecal injection, allowing direct delivery to the central nervous system.
The candidate is being evaluated in the global Phase 1-3 FUSION trial (NCT04768972) in people living with FUS-ALS (搜索). In 2024, Otsuka Pharmaceutical entered into an exclusive global licensing agreement with Ionis Pharmaceuticals to further develop and commercialize ulefnersen, which was discovered and developed by Ionis.
Ulefnersen has been granted Fast Track designation for FUS-ALS (搜索) by the U.S. FDA and Orphan designation for ALS by the U.S. FDA, the European Medicines Agency (搜索) and Swissmedic (搜索).