The World Orphan Drug Congress USA 2023 was held from May 23-25, 2023 at the Gaylord National Resort & Convention Center in National Harbor, MD. This conference is focused solely on orphan drugs and rare diseases and features stakeholders from across the rare disease world, such as patients, regulatory authorities, pharmaceutical companies, patient advocacy organizations, families, clinicians, scientists and more all coming together to share ideas and further the shared goal of improving outcomes for rare disease patients. This year, Patient Worthy was in attendance to cover the event.

During the conference, I sat down with Reenie McCarthy, CEO of Stealth BioTherapeutics. Reenie spoke at a presentation at the event titled “Ultra-Rare: Challenge in Clinical Development.” 

Stealth has been active in the space of ultra-rare disease drug development. It’s critical for pharma companies to be investing in this side of rare disease, but it’s a difficult route to take, and many of the difficulties encountered in orphan drug development are magnified for ultra-rare conditions, which may only have a few hundred known patients.

“We were actually approached by patient advocates and asked to start working on a trial, so we partnered with them from the outset to do some pre-clinical work.” – Reenie

Stealth works with the Barth Syndrome Foundation, a worldwide organization dedicated to Barth syndrome, an ultra-rare illness with only a few hundred documented cases. However, the condition is likely underdiagnosed. Collaborating with an advocacy group from the beginning has some real advantages, and advocates were able to provide input into aspects of development, such as clinical trial protocols, from the outset.

“We designed and implemented a unique patient-reported outcome measure, which was to assess fatigue in the disease, and that was something that we partnered with the patient community in order to develop.”

Challenges in ultra-rare include that there hasn’t been much regulation introduced surrounding ultra-rare conditions specifically; in fact, there’s no set definition of ultra-rare conditions legally. With the lack of other resources, such as animal models, companies often have to opt for smaller scale trials and designs.

“We couldn’t have done this without the Barth Syndrome Foundation. They’ve been incredibly strong and resilient partners. People need to hear from the patients; the FDA needs to, Congress needs to, and that voice has a different level of authenticity.”