CureDRPLA is funding a number of research projects in hopes of rapidly developing novel therapeutics for DRPLA. Our primary motivation is time, and therefore we are working strategically with both academic and commercial partners to advance DRPLA treatments to the clinic as quickly as possible. A lay description of projects sponsored by CureDRPLA is provided below. 

Preclinical Projects

Preclinical projects are research projects that take place before clinical trials can begin. They aim to advance the diseases knowledge, for example finding and testing potential therapies in cell models and animal models.

DRPLA affected individuals have a CAG expansion in the Atrophin-1 (ATN1) gene, this mutation causes an abnormal ATN1 protein that will accumulate in the cells and will ultimately result in DRPLA (read more about DRPLA here). ​Our primary therapeutic modality of interest is to reduce the levels of ATN1 in patients. 

Antisense therapy has emerged as an exciting and promising strategy for the treatment of various neurodegenerative disorders (i.e. spinal muscular atrophy, Duchenne muscular dystrophy). Antisense oligonucleotides (ASOs) can block the ability of a certain gene to make a protein. ASOs could prevent ATN1 protein aggregation in DRPLA, and therefore reverse or stop DRPLA progression.

Ongoing projects

• Timothy Yu (Boston Children’s Hospital, US) and Dr. Vik Khurana (Harvard Medical School, US), along with their teams, generated ASOs capable of reducing human ATN1 levels. The top ASO candidates are being further validated in patient-derived iPSCs to investigate whether the DRPLA phenotype in these cells can be reversed or prevented by ASO treatment. Furthermore, they are also investigating what role ATN1 plays in cells and if there are any side effects to reducing ATN1 levels.
• Prof Paola Giunti (University College London, UK) and her team are investigating if DRPLA cellular models recapitulate the features of this condition and to test treatments to halt the progression. They are collaborating with two different companies that developed a treatment for other types of ataxias, and they are testing if these treatments may be effective in DRPLA.

 Completed

• Dr. Elizabeth Ross (Weill Cornell Medicine, US) collected skin biopsies from 16 DRPLA patients. Her team reprogrammed these skin cells into induced pluripotent stem cells (iPSCs), which means that these cells are now capable of developing into different cell types (e.g. brain cells – neurons). Patient-derived iPSCs are used as a tool to understand and model DRPLA, and also to develop and test candidate drugs.
• Dr. Giovanni Stevanin (Institut du Cerveau, France) and Dr. Manolis Fanto (King’s College London, UK) tested the efficacy of ASOs in human cell lines, including patient-derived iPSCs. The results of this project are expected to be published in a scientific journal soon.
• siRNA are small molecules that interfere with the expression of specific genes and prevent protein formation. DRPLA-specific siRNA could prevent ATN1 protein aggregation, and therefore reverse or stop DRPLA progression. Dr. Khvorova (University of Massachusetts, US) developed siRNA’s targeting ATN1. Dr Carroll (University of Washington) tested this tool compound in DRPLA mice, where it showed a significant decrease in ATN1 levels.

In addition, Ionis Pharmaceuticals has an advancing research program targeting ATN1 for the treatment of DRPLA. Ionis is working hard to evaluate molecules in hope of identifying a human candidate that could ultimately be advanced into the clinic over the next couple of years.

Understanding the Impact of DRPLA

CureDRPLA and Ataxia UK are working closely with the DRPLA community to gather more information about the impact of DRPLA on affected individuals, their relatives, and their caregivers. CureDRPLA engaged Casimir to conduct qualitative interviews with eight DRPLA caregivers and two patients to understand symptoms, natural history, impact on patient function and quality of life, and input on the outcomes that are important and relevant to them. Six caregivers reported findings from two or more family members resulting in descriptions from 19 affected individuals. The findings from these interviews will be published in a scientific journal.

CureDRPLA and the National Ataxia Foundation organized an Externally-Led Patient Focused Drug Development (EL-PFDD) that allowed the Food and Drug Administration (FDA) in the United States to hear directly from patients, their families, caregivers, and patient advocates. The DRPLA community reported which symptoms matter the most to them, the impact the disease has on patient’s daily lives, and patient’s expectations of future treatments. You can access the replay here. NAF and CureDRPLA have prepared a report to summarise all the feedback gathered at this meeting. The report can be accessed here.  Future applications for therapy approvals will use the report as a reference when evaluating the effectiveness of the treatment.

DRPLA Natural History and Biomarkers Study (DRPLA NHBS)

CureDRPLA and Ataxia UK are coordinating the DRPLA NHBS. This study will collect health information from DRPLA individuals over three years to understand how this condition develops over time. This study will also provide a platform to support the design and conduct of clinical trials in the future. The study also recruits participants without ataxia, so that they are able to compare how individuals with DRPLA differ from those without. 

This project aims to characterize the natural history of DRPLA in both juvenile- and adult-onset patients. Participating in this study will involve annual appointments at the clinics where the neurologist will do some clinical assessments (e.g. ataxia scales, brain MRI, blood collection, etc.).

This study has sites in the United Kingdom and the United States, which are currently recruiting participants:

• Paola Giunti – University College London (UK)
• Henry Houlden – University College London (UK)
• Yael Shiloh-Malawsky – University of North Carolina (US)
• Claire Miller – NYU Grossman School of Medicine (US)

You can find out more about the study by watching this video. Contact details for study investigators can be found here. 

Information Sites and Support Groups

Support Organizations/Groups

Dentatorubral-pallidoluysian atrophy (DRPLA) Facebook Group https://www.facebook.com/groups/144167217964 

Ataxia UK    https://www.ataxia.org.uk

Ataxia UK has a Helpline service dedicated to supporting people affected by ataxia. As well as providing support and information around diagnosis, treatment and living with ataxia, there is a range of other issues they can help with (e.g. benefits, aid and adaptations, employment). For those in the UK, you can get in touch by calling 0800 995 6037 or by emailing help@ataxia.org.uk.

Global Genes    globalgenes.org

The National Ataxia Foundation    ataxia.org/about-naf

Ataxia Support Group    livingwithataxia.org

Information Sites

NIH – Genetics Home Reference
https://ghr.nlm.nih.gov/condition/dentatorubral-pallidoluysian-atrophy#

OMIM® – Online Mendelian Inheritance in Man
https://www.omim.org/entry/125370

National Centre for Biotechnology-Gene Review
https://www.ncbi.nlm.nih.gov/books/NBK1491/

GARD – Genetic and Rare Diseases Information Centre
https://rarediseases.info.nih.gov/diseases/5643/dentatorubral-pallidoluysian-atrophy

YouTube Channels

CureDRPLA YouTube Channel

Cure Disease Kuri Channel

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