Repurposed Drug Study in DESSH Syndrome Update

The DESSH Foundation, Mayo Clinic, and Rare People – The Research Charity have a brief update for the DESSH community regarding the repurposed drug research study at the Mayo Clinic.

The DESSH Foundation remains in regular communication with the team at Mayo Clinic as the study moves forward. The study recently received funding from Cures Within Reach, which you can read more about here: https://www.cureswithinreach.org/2026/02/25/press-release-cures-within-reach-selected-three-clinical-trials-in-rare-ultrarare/

At this stage, the study is still undergoing the institutional review board (IRB) approval process. Because of this, detailed information about participation is not yet available. The timeframe for this approval is estimated to be 30 to 90 days.

Once approval is finalized, Mayo Clinic will share additional information with us including inclusion and exclusion criteria and the expectations and responsibilities for participating patients and families.

When the study officially launches, a webinar will be held to walk the community through the details and answer questions.

We can share that enrollment is expected to occur on a rolling basis over approximately two years. It is open to patients under the age of 18, including international patients, and will study WAC blood levels, and behavior assessments. There is no placebo – every participant will receive drug treatment. The design of the study may allow participants to work with their own local physicians who are willing to prescribe the medication, coordinate blood work to be sent to Mayo Clinic, and complete behavioral testing at baseline, 6 months, and 12 months of treatment.

If you already have a physician in your area who may be willing to participate in this process, please have them contact Caitlin@dessh.org. This may help connect other families in your region or country with potential providers when the study opens.

While patients already taking the medication cannot enroll in this study, we welcome feedback and/or reports from anyone wishing to share their outcomes with the community. Your experience is equally valuable to further research.

Patients in the United Kingdom

There is a parallel effort in the United Kingdom to study the repurposed drug as a potential treatment for DESSH. This work is being coordinated through a collaboration between Rare People – The Research Charity (www.rarepeople.org) and clinicians at Guy’s and St Thomas’ Hospital in London.

Rare People, which formally launched on 1st March, has raised the £100,000 needed to

support the initial phase of a UK-based clinical study. This follows the same Mayo protocol

but differs in that all treatments, assessments, and tests will be undertaken by Guy’s and St Thomas’. The charity funding will pay for the care and the data analysis. The final inclusion criteria are currently being developed, and MAY include those above 18 and also those outside the UK, who cannot get local clinicians to treat them as part of the Mayo study.

An initial online meeting for UK families has been organized by Rare People and will take

place on 19 March at 6pm UK time. The session will be led Dr. Dagana, the

geneticist leading the study. Further communications will be sent to UK families about this.

Although funding has been secured, this only pays for the initial year of the studies in the UK and for limited numbers of children. We hope that families can help further fundraise to help pay for increasing the numbers of participants, as well as increasing the length of the study. For those outside of the UK we ask that funding is channeled through the DESSH Foundation and for those in the UK through Rare People.

We will continue sharing updates as more information becomes available. Thank you for your continued patience and support as this research moves forward.