About this site
Every source used
All 26 sources referenced anywhere on this site, grouped by the kind of evidence each one is — because a government database and a company press release are not equivalent, and it matters which one a claim rests on.
Government / regulator5
National Institute of Neurological Disorders and Stroke
NIH
US government reference on neurological conditions, written for the public.
Genetic and Rare Diseases Information Center (GARD)
NIH / NCATS
Plain-language summaries of rare conditions with links onward to specialist sources.
US National Library of Medicine
Per-condition genetics pages, including individual SCA types. Written for non-specialists.
US Food and Drug Administration
The authoritative record of what the FDA has approved and the exact wording of each label.
US Food and Drug Administration
Machine-readable access to approved US drug labels. This site queries it live.
Public registry7
US National Library of Medicine
Registry of clinical studies worldwide. Records are written by sponsors, so summaries are sponsor claims; status and dates are the reliable parts.
EMBL-EBI
Search across biomedical literature including PubMed records and preprints. Flags which papers are open access.
Study BHV4157-206-RWE: troriluzole in spinocerebellar ataxia
ClinicalTrials.gov
The real-world-evidence study that formed the basis of the troriluzole application.
Study BHV4157-206: troriluzole in adults with spinocerebellar ataxia
ClinicalTrials.gov
Placebo-controlled study of troriluzole across SCA types 1, 2, 3, 6 and 7.
Study BHV4157-201: troriluzole in spinocerebellar ataxia
ClinicalTrials.gov
Earlier supportive study cited in the application.
Troriluzole expanded access protocol
ClinicalTrials.gov
Expanded access programme. Check the record for current status before relying on it.
STRIDES: SLS-005 (trehalose) in spinocerebellar ataxia
ClinicalTrials.gov
Seelos Therapeutics phase 2b/3 study; the registry record lists an actual completion date of November 2023.
Peer-reviewed literature1
University of Washington / NCBI Bookshelf
Expert-authored, peer-reviewed chapters on inherited conditions. The standard reference for SCA genotypes. Technical but authoritative.
Patient organisation7
National Ataxia Foundation
The main US patient organisation for the ataxias. Support groups, clinic directory, research news and a patient registry.
National Ataxia Foundation
Running list of drug development announcements across the ataxias, compiled from company releases.
Ataxia UK
UK patient organisation. Publishes practical guidance on living with ataxia and funds research.
Rare Disease Video: Spinocerebellar Ataxia
National Organization for Rare Disorders
Short video overview with accompanying text. Independently states that there are no FDA-approved therapies and that treatment is symptomatic and supportive.
SCA27B Ataxia Foundation
Organisation focused on the FGF14-related form. Hosts awareness videos, including material on the ataxia in Bill Nye’s family, and specialist Q&A sessions.
National Ataxia Foundation video channel
National Ataxia Foundation
Years of research updates, conference sessions and interviews with people living with ataxia.
National Organization for Rare Disorders
NORD
Rare disease umbrella organisation. Useful for financial assistance programmes and general rare disease navigation.
Securities filing1
Biohaven Ltd. Form 10-K, fiscal year 2025
US Securities and Exchange Commission
Annual report. Filings are legally accountable in a way press releases are not, which makes them a better source for programme status.
Company statement2
Biohaven Ltd. (press release, 4 November 2025)
The company’s own announcement of the FDA decision. Primary for the fact of the decision; the framing around it is the company’s.
Biohaven Ltd. (press release, 11 February 2025)
Source for the application timeline and for the company’s prevalence estimates.
Trade press3
FDA issues Complete Response Letter for spinocerebellar ataxia agent troriluzole
NeurologyLive
Trade press account of the FDA decision, including the stated concerns about the externally controlled design.
Vyglxia (troriluzole) approval history
Drugs.com
Convenient dated timeline of the application. Secondary; verify anything important against the filing or press release.
Practical Neurology
Contemporary account of the review timeline and the expanded access protocol.
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How this site was built
The method behind these sources, and the limitations that come with it.