top of page

Anavex Life Sciences Reports Publication in Medical Journal for Continued Commitment to Improve RSBQ

Rett Syndrome Caregiver Outcome Measure

NEW YORK – June 12, 2023

Anavex Life Sciences Corp. (“Anavex” or the “Company”) (Nasdaq: AVXL), a clinical-stage biopharmaceutical company developing differentiated therapeutics for the treatment of neurodegenerative and neurodevelopmental disorders including Alzheimer’s disease, Parkinson’s disease, Rett syndrome and other central nervous system (CNS) disorders, today announced the publication of a relevant new peer-reviewed study in the American Journal on Intellectual and Developmental Disabilities, entitled ‘Rett Syndrome Behaviour Questionnaire in Children and Adults With Rett Syndrome: Psychometric Characterization and Revised Factor Structure’.[1]

The study reports distribution of scores and other statistical features of the Rett Syndrome Behaviour Questionnaire (RSBQ) in more than 600 children and adults with Rett syndrome. It also re-examines the structure of the questionnaire, specifically the grouping of questions (items) into different subscales. This evaluation led authors to propose some changes to the organization of the questions (i.e., revised subscales). The study, which represents the largest ever analysis of the RSBQ and the first report of the instrument in adults with Rett Syndrome, was the result of an international collaboration including anonymized databases from the United States, Australia, United Kingdom, and Denmark. The ultimate goal of the project was to provide reference values and other metrics of the RSBQ for its clinical application and implementation in research studies. The study was partially funded by a grant from the International Rett Syndrome Foundation (IRSF). All analyses performed in the study are available to the community through a website hosted by IRSF.

The RSBQ was developed by a British team of clinicians and researchers to better delineate behavioral problems in children with Rett syndrome. Over the course of the following two decades, the use of the RSBQ has been expanded to observational studies in adults with Rett syndrome and efficacy assessments. The RSBQ’s implementation as global outcome measures in FDA-regulated clinical trials is the result of its comprehensive nature since the questionnaire includes not only behaviors but also behavior-related symptoms. Indeed, most regulated trials include as co-primary efficacy endpoints the RSBQ, as a caregiver measure, and the Clinical Global Impression of Improvement (CGI-I) as an investigator assessment. For all these reasons, this psychometric study is timely and significant, providing additional support for the use of the RSBQ in children and adults as well as reference values and revised subscales for its improved use.

In the EXCELLENCE Phase 2/3 ANAVEX®2-73-RS-003 Rett syndrome pediatric clinical trial, the characterized Rett Syndrome Behaviour Questionnaire (RBSQ), together with the Clinical Global Impression Improvement Scale (CGI-I), represent the co-primary efficacy endpoints of the study.

“This paper is a further demonstration of Anavex’s involvement as part of the team of clinicians and commitment to the rare disease and especially to the Rett syndrome community,” said Christopher U Missling, PhD, President and Chief Executive Officer of Anavex. "We are looking forward to the topline data from the EXCELLENCE Phase 2/3 ANAVEX®2-73-RS-003 Rett syndrome pediatric clinical trial in the second half of 2023.”

The paper can be accessed online at:

About Rett Syndrome

Rett syndrome is a devastating, non-inherited genetic post-natal progressive neurodevelopmental disorder that occurs almost exclusively in girls and leads to severe impairments, affecting nearly every aspect of the child’s life: their ability to speak, walk, eat and easily breathe. The hallmark of Rett syndrome is near constant repetitive hand movements while awake. The disease is characterized by normal early growth and development (6 to 18 months) followed by a slowing of development, loss of purposeful use of the hands, distinctive hand movements, autistic features, slowed brain and head growth, ataxia, seizures and intellectual disability.

Rett syndrome is caused by mutations in the MECP2 gene and strikes all racial and ethnic groups. The disease occurs worldwide in approximately one in every 10,000 to 15,000 live births. The population of patients with Rett syndrome is estimated to be approximately 11,000 patients in the U.S. There is currently no cure for Rett syndrome.

About Anavex Life Sciences Corp.

Anavex Life Sciences Corp. (Nasdaq: AVXL) is a publicly traded biopharmaceutical company dedicated to the development of novel therapeutics for the treatment of neurodegenerative and neurodevelopmental disorders, including Alzheimer's disease, Parkinson's disease, Rett syndrome, and other central nervous system (CNS) diseases, pain, and various types of cancer. Anavex's lead drug candidate, ANAVEX®2-73 (blarcamesine), has successfully completed a Phase 2a and recently a Phase 2b/3 clinical trial for Alzheimer's disease, a Phase 2 proof-of-concept study in Parkinson's disease dementia, and both a Phase 2 and a Phase 3 study in adult patients with Rett syndrome. ANAVEX®2-73 is an orally available drug candidate that restores cellular homeostasis by targeting sigma-1 and muscarinic receptors. Preclinical studies demonstrated its potential to halt and/or reverse the course of Alzheimer's disease. ANAVEX®2-73 also exhibited anticonvulsant, anti-amnesic, neuroprotective, and anti-depressant properties in animal models, indicating its potential to treat additional CNS disorders, including epilepsy. The Michael J. Fox Foundation for Parkinson's Research previously awarded Anavex a research grant, which fully funded a preclinical study to develop ANAVEX®2-73 for the treatment of Parkinson's disease. ANAVEX®3-71, which targets sigma-1 and M1 muscarinic receptors, is a promising clinical stage drug candidate demonstrating disease-modifying activity against the major hallmarks of Alzheimer's disease in transgenic (3xTg-AD) mice, including cognitive deficits, amyloid, and tau pathologies. In preclinical trials, ANAVEX®3-71 has shown beneficial effects on mitochondrial dysfunction and neuroinflammation. Further information is available at You can also connect with the company on Twitter, Facebook, Instagram, and LinkedIn.

Forward-Looking Statements

Statements in this press release that are not strictly historical in nature are forward-looking statements. These statements are only predictions based on current information and expectations and involve a number of risks and uncertainties. Actual events or results may differ materially from those projected in any of such statements due to various factors, including the risks set forth in the Company’s most recent Annual Report on Form 10-K filed with the SEC. Readers are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date hereof. All forward-looking statements are qualified in their entirety by this cautionary statement and Anavex Life Sciences Corp. undertakes no obligation to revise or update this press release to reflect events or circumstances after the date hereof.

For Further Information:

Anavex Life Sciences Corp.

Research & Business Development

Toll-free: 1-844-689-3939


Andrew J. Barwicki Investor Relations Tel: 516-662-9461

[1] Oberman LM, Leonard H, Downs J, Cianfaglione R, Stahlhut M, Larsen JL, Madden KV, Kaufmann WE. Rett Syndrome Behaviour Questionnaire in Children and Adults With Rett Syndrome: Psychometric Characterization and Revised Factor Structure. Am J Intellect Dev Disabil. 2023 May 1;128(3):237-253. doi: 10.1352/1944-7558-128.3.237.PMID: 37104862.



bottom of page