Updates on ALDEBARAN, a Phase 2a Trial in Angelman Syndrome

Quick Overview

Roche Pharmaceuticals provided an update on the Alogabat study, which is in a phase 2a trial for Angelman Syndrome. The study aims to test the safety and efficacy of Alogabat, an oral tablet that selectively enhances GABAA α5 receptor function. The ALDEBARAN study, which is a phase 2 trial in deletion Angelman patients, has already started and will include 56 patients aged 5 to 17. The study will assess safety, pharmacokinetics, and exploratory effects of the drug. Roche is also in discussions with interested companies regarding the Rugonersen study and hopes to finalize a deal soon.


This talk provides an update on the Alogabat study, which is currently in a phase 2a trial for Angelman Syndrome. The update was presented by Shady Sedhom from Roche Pharmaceuticals at the 2023 FAST Science Summit.

About the Speaker

Shady Sedhom is a global patient partnership director at Roche Pharmaceuticals, with a focus on neurodevelopmental disorders.

Alogabat and Angelman Syndrome

Alogabat is being tested in patients with Angelman Syndrome deletion. Angelman Syndrome is caused by a mutation in chromosome 15q, specifically in the UBE3A part of the gene. Deletion patients have longer missing genes, including the GABA gene responsible for creating GABA receptors.

Importance of GABA Receptors

GABA receptors play a crucial role in brain function. They are responsible for communication between neurons through synapses. Studies have shown that GABAA α5 receptors may contribute to greater clinical severity in Angelman Syndrome deletion. Decreasing these receptors in deletion patients may worsen the symptoms in different domains.

Alogabat and GABAA α5 Receptor Function

Alogabat is an oral tablet that has the potential to selectively enhance the function of GABAA α5 receptors. By improving the function of these receptors, Alogabat may potentially aid brain development in Angelman Syndrome deletion patients.


ALDEBARAN is a phase 2 trial studying the effects of Alogabat in deletion patients. The study is open-label, meaning all participants will receive Alogabat and there will be no placebo group. The trial aims to recruit 56 patients aged 5 to 17, both male and female, with the deletion genotype. The study will be conducted in multiple sites across six countries.

Study Objectives

The ALDEBARAN study has several objectives, including assessing the safety of Alogabat in Angelman Syndrome deletion patients. The study will also evaluate the pharmacokinetics of the drug and explore any potential effects. The study duration is approximately 24 weeks, including a screening period, 12 weeks of treatment, and a follow-up period.

Acknowledgements and Next Steps

The speaker acknowledges the team working on Alogabat and extending its use to Angelman Syndrome. The team has put in significant effort to conduct two studies with one drug.

Shifting gears to Rugonersen, discussions with interested companies are ongoing. The goal is to finalize a deal soon, which may allow for an extension of the study timeline. More information will be provided once the deal is approved and signed.


The ALDEBARAN study is currently underway, testing the effects of Alogabat in Angelman Syndrome deletion patients. For more information, individuals are encouraged to speak with their doctors or visit clinicaltrials.gov. The speaker expresses gratitude to the trial participants, principal investigators, site staff, and everyone involved in both studies.

Talk details

  • Title: Updates on ALDEBARAN, a Phase 2a Trial in Angelman Syndrome
  • Author(s): Shady Sedhom
  • Author(s)’ affiliation: Roche Pharmaceuticals
  • Publication date: 2023-11-12
  • Collection: 2023 FAST Science Summit