Ultragenyx Receives Breakthrough Therapy Designation for GTX-102 in Angelman Syndrome
Ultragenyx Pharmaceutical (NASDAQ: RARE) has received FDA Breakthrough Therapy Designation for GTX-102 (apazunersen) in treating Angelman syndrome. The designation is based on promising Phase 1/2 study results involving 74 patients aged 4-17 years, showing consistent developmental improvements across multiple symptom domains for up to 3 years.
The company's Phase 3 Aspire study, which began in December 2024, aims to enroll approximately 120 children with Angelman syndrome. Additionally, the Aurora study, evaluating GTX-102 in other Angelman syndrome genotypes and ages, is expected to start in the second half of 2025.
Ultragenyx Pharmaceutical (NASDAQ: RARE) ha ottenuto la Designazione di Terapia Sperimentale Innovativa (Breakthrough Therapy Designation) dalla FDA per GTX-102 (apazunersen) nel trattamento della sindrome di Angelman. La designazione si basa su risultati promettenti dello studio di Fase 1/2 che ha coinvolto 74 pazienti di età compresa tra 4 e 17 anni, mostrando miglioramenti costanti nello sviluppo in diversi ambiti sintomatici per un periodo fino a 3 anni.
Lo studio Aspire di Fase 3 dell'azienda, iniziato a dicembre 2024, punta a reclutare circa 120 bambini con sindrome di Angelman. Inoltre, lo studio Aurora, che valuterà GTX-102 in altri genotipi e fasce d'età della sindrome di Angelman, è previsto per la seconda metà del 2025.
Ultragenyx Pharmaceutical (NASDAQ: RARE) ha recibido la Designación de Terapia Innovadora (Breakthrough Therapy Designation) por parte de la FDA para GTX-102 (apazunersen) en el tratamiento del síndrome de Angelman. Esta designación se basa en resultados prometedores del estudio de Fase 1/2 con 74 pacientes de entre 4 y 17 años, mostrando mejoras consistentes en el desarrollo a lo largo de múltiples dominios sintomáticos durante hasta 3 años.
El estudio Aspire de Fase 3 de la compañía, iniciado en diciembre de 2024, tiene como objetivo inscribir aproximadamente a 120 niños con síndrome de Angelman. Además, el estudio Aurora, que evaluará GTX-102 en otros genotipos y edades del síndrome de Angelman, se espera que comience en la segunda mitad de 2025.
Ultragenyx Pharmaceutical (NASDAQ: RARE)는 Angelman 증후군 치료를 위한 GTX-102(아파주네르센)에 대해 FDA 혁신 치료 지정(Breakthrough Therapy Designation)을 받았습니다. 이 지정은 4세에서 17세 사이의 74명 환자를 대상으로 한 1/2상 연구에서 3년까지 여러 증상 영역에서 일관된 발달 개선을 보인 유망한 결과를 바탕으로 합니다.
회사의 3상 Aspire 연구는 2024년 12월에 시작되었으며 Angelman 증후군 아동 약 120명을 등록할 예정입니다. 또한 GTX-102를 다른 Angelman 증후군 유전자형과 연령대에서 평가하는 Aurora 연구는 2025년 하반기에 시작될 예정입니다.
Ultragenyx Pharmaceutical (NASDAQ : RARE) a obtenu la désignation de thérapie révolutionnaire (Breakthrough Therapy Designation) de la FDA pour GTX-102 (apazunersen) dans le traitement du syndrome d'Angelman. Cette désignation repose sur des résultats prometteurs d'une étude de phase 1/2 impliquant 74 patients âgés de 4 à 17 ans, montrant des améliorations développementales constantes dans plusieurs domaines symptomatiques pendant jusqu'à 3 ans.
L'étude Aspire de phase 3 de la société, débutée en décembre 2024, vise à recruter environ 120 enfants atteints du syndrome d'Angelman. De plus, l'étude Aurora, qui évaluera GTX-102 sur d'autres génotypes et tranches d'âge du syndrome d'Angelman, devrait débuter dans la seconde moitié de 2025.
Ultragenyx Pharmaceutical (NASDAQ: RARE) hat die FDA Breakthrough Therapy Designation für GTX-102 (Apazunersen) zur Behandlung des Angelman-Syndroms erhalten. Die Auszeichnung basiert auf vielversprechenden Ergebnissen der Phase-1/2-Studie mit 74 Patienten im Alter von 4 bis 17 Jahren, die über einen Zeitraum von bis zu 3 Jahren konsistente Entwicklungsverbesserungen in mehreren Symptombereichen zeigten.
Die Phase-3-Aspire-Studie des Unternehmens, die im Dezember 2024 begann, soll etwa 120 Kinder mit Angelman-Syndrom einschließen. Darüber hinaus soll die Aurora-Studie, die GTX-102 bei anderen Genotypen und Altersgruppen des Angelman-Syndroms untersucht, in der zweiten Hälfte des Jahres 2025 starten.
- FDA Breakthrough Therapy Designation received, potentially expediting development and review process
- Positive Phase 1/2 clinical data showing sustained improvements in patients for up to 3 years
- Phase 3 study enrollment progressing rapidly with strong community support
- None.
Insights
FDA Breakthrough Therapy Designation significantly accelerates GTX-102's path to market while validating its strong clinical potential.
Ultragenyx's receipt of Breakthrough Therapy Designation (BTD) for GTX-102 represents a major regulatory milestone with substantial implications for both the company's development timeline and commercial prospects. This designation, granted only when preliminary evidence indicates potentially substantial improvements over existing therapies, unlocks several critical advantages including intensive FDA guidance, rolling review, and eligibility for Priority Review.
The BTD is particularly significant as it's based on compelling Phase 1/2 data showing consistent developmental gains across multiple symptom domains in 74 patients with Angelman syndrome - a rare, debilitating neurodevelopmental disorder with no FDA-approved treatments. The study demonstrated rapid, sustained improvements when treated for up to 3 years, suggesting GTX-102's antisense oligonucleotide approach targeting UBE3A-AS is producing meaningful clinical benefits.
The company's Phase 3 Aspire study is currently enrolling approximately 120 children ages 4-17 with full maternal UBE3A gene deletion, expected to complete enrollment in 2025. Additionally, the upcoming Aurora study will expand investigation to other Angelman syndrome genotypes and age groups later this year, broadening the potential patient population.
For Ultragenyx, this designation significantly enhances GTX-102's commercial prospects by potentially reducing time-to-market by months, lowering development costs, and providing competitive advantages. With the Angelman syndrome therapeutic landscape relatively uncrowded, GTX-102 has potential to become a first-in-class treatment addressing a significant unmet medical need affecting approximately 60,000 patients in developed markets.
Phase 3 Aspire study enrollment on track to complete in 2025
Aurora study to evaluate GTX-102 in other Angelman syndrome genotypes and ages expected to initiate later this year
NOVATO, Calif., June 27, 2025 (GLOBE NEWSWIRE) -- Ultragenyx Pharmaceutical Inc. (NASDAQ: RARE), today announced that it has received Breakthrough Therapy Designation from the U.S. Food and Drug Administration (FDA) for GTX-102 (apazunersen) as a treatment for Angelman syndrome.
"FDA Breakthrough Therapy Designation underscores both the urgent need for an effective treatment for patients and families affected by Angelman syndrome and the clinically meaningful results demonstrated to date with GTX-102,” said Eric Crombez, M.D., chief medical officer at Ultragenyx. "Based on the strength of the Phase 2 data and with strong support and interest from the Angelman syndrome community, our Phase 3 Aspire study is rapidly enrolling across our global sites. We look forward to advancing GTX-102 through the development process as rapidly as possible to bring this potential treatment to patients.”
The FDA’s decision is based on preliminary clinical evidence including positive data from the Phase 1/2 study in 74 patients (4-17 years of age) with a full maternal UBE3A gene deletion, that showed participants have made consistent developmental gains with rapid, sustained and continuing improvements across multiple symptom domains when treated for up to 3 years. Breakthrough Therapy Designation aims to expedite the development and review of drugs that are intended to treat serious or life-threatening diseases and whose preliminary clinical evidence indicates that the drug may demonstrate substantial improvement on one or more clinically significant endpoints over existing therapies.
Enrollment in the global Phase 3 Aspire study (NCT06617429) began in December 2024 and is expected to enroll approximately 120 children ages four to 17 with Angelman syndrome with a genetically confirmed diagnosis of full maternal UBE3A gene deletion. The Aurora study will evaluate GTX-102 across other Angelman syndrome genotypes and ages and is expected to initiate in the second half of 2025. Families can learn more by visiting www.ultraclinicaltrials.com.
About GTX-102 (apazunersen)
GTX-102 (apazunersen) is an investigational antisense oligonucleotide (ASO) therapy delivered via intrathecal administration and designed to target and inhibit expression of the UBE3A antisense transcript (UBE3A-AS) to prevent silencing of the paternally inherited allele of the UBE3A gene and reactivate expression of the deficient protein. GTX-102 has been granted Breakthrough Therapy Designation, Orphan Drug Designation, Rare Pediatric Disease Designation, and Fast Track Designation from the FDA and Orphan Designation and PRIME designation from the EMA.
About Angelman Syndrome
Angelman syndrome is a rare, neurogenetic disorder caused by loss-of-function of the maternally inherited allele of the UBE3A gene. The maternal-specific inheritance pattern of Angelman syndrome is due to genomic imprinting of UBE3A in neurons of the central nervous system (CNS), a naturally occurring phenomenon in which the maternal UBE3A allele is expressed and the paternal UBE3A is not. Silencing of the paternal UBE3A allele is regulated by the UBE3A-AS, the intended target of GTX-102. In almost all cases of Angelman syndrome, the maternal UBE3A allele is either missing or mutated, resulting in limited to no protein expression. This condition is generally not inherited but instead occurs spontaneously. It is estimated to affect approximately 60,000 people in commercially accessible geographies.
Angelman syndrome is a lifelong neurodevelopmental disorder that causes cognitive impairment, motor impairment, balance issues and debilitating seizures. Some individuals with Angelman syndrome are unable to walk and most do not speak. Anxiety and disturbed sleep can be serious challenges in individuals with Angelman syndrome. Although individuals with Angelman syndrome have a normal lifespan, they require continuous care and are unable to live independently. Angelman syndrome is not a degenerative disorder, but the loss of the UBE3A protein expression in neurons results in abnormal communications between neurons. Angelman syndrome is often misdiagnosed as autism or cerebral palsy. There are no currently approved therapies for Angelman syndrome; however, several symptoms of this disorder can be reversed in adult animal models of Angelman syndrome, suggesting that improvement of symptoms can potentially be achieved at any age.
About Ultragenyx
Ultragenyx is a biopharmaceutical company committed to bringing novel therapies to patients for the treatment of serious rare and ultra-rare genetic diseases. The company has built a diverse portfolio of approved medicines and treatment candidates aimed at addressing diseases with high unmet medical need and clear biology, for which there are typically no approved therapies treating the underlying disease.
The company is led by a management team experienced in the development and commercialization of rare disease therapeutics. Ultragenyx’s strategy is predicated upon time- and cost-efficient drug development, with the goal of delivering safe and effective therapies to patients with the utmost urgency.
For more information on Ultragenyx, please visit the company's website at: www.ultragenyx.com.
Forward-Looking Statements and Use of Digital Media
Except for the historical information contained herein, the matters set forth in this press release, including statements related to Ultragenyx's expectations and projections regarding its future operating results and financial performance, business plans and objectives for GTX-102, expectations regarding the tolerability and safety of GTX-102, and future clinical and regulatory developments for GTX-102 are forward-looking statements within the meaning of the "safe harbor" provisions of the Private Securities Litigation Reform Act of 1995. Such forward-looking statements involve substantial risks and uncertainties that could cause our clinical development programs, collaboration with third parties, future results, performance or achievements to differ significantly from those expressed or implied by the forward-looking statements. Such risks and uncertainties include, among others, the uncertainty of clinical drug development and unpredictability and lengthy process for obtaining regulatory approvals, the ability of the company to successfully develop GTX-102, the company’s ability to achieve its projected development goals in its expected timeframes, the risk that results from earlier studies may not be predictive of future study results, risks related to adverse side effects, risks related to reliance on third party partners to conduct certain activities on the company’s behalf, smaller than anticipated market opportunities for the company’s products and product candidates, manufacturing risks, competition from other therapies or products, and other matters that could affect sufficiency of existing cash, cash equivalents and short-term investments to fund operations, the company’s future operating results and financial performance, the timing of clinical trial activities and reporting results from same, and the availability or commercial potential of Ultragenyx’s products and drug candidates. Ultragenyx undertakes no obligation to update or revise any forward-looking statements.
For a further description of the risks and uncertainties that could cause actual results to differ from those expressed in these forward-looking statements, as well as risks relating to the business of Ultragenyx in general, see Ultragenyx's Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission (SEC) on May 7, 2025, and its subsequent periodic reports filed with the SEC.
In addition to its SEC filings, press releases and public conference calls, Ultragenyx uses its investor relations website and social media outlets to publish important information about the company, including information that may be deemed material to investors, and to comply with its disclosure obligations under Regulation FD. Financial and other information about Ultragenyx is routinely posted and is accessible on Ultragenyx’s Investor Relations website (https://ir.ultragenyx.com/) and LinkedIn website (https://www.linkedin.com/company/ultragenyx-pharmaceutical-inc-/).
Ultragenyx Contacts
Investors
Joshua Higa
+1-415-475-6370
ir@ultragenyx.com
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Joey Fleury
media@ultragenyx.com
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