Prilenia’s Phase 3 Huntington’s Disease Clinical Trial Achieves 50% Enrollment

July 8, 2021 12:00 UTC


  • Prilenia’s global phase 3 trial in Huntington’s Disease (PROOF-HD) is ahead of schedule after enrolling 50% (240) of target 480 participants
  • 120 of the participants were enrolled in the past 6 weeks
  • PROOF-HD is the most advanced clinical trial in HD assessing impact on clinical progression

NAARDEN, the Netherlands--(BUSINESS WIRE)-- Prilenia Therapeutics B.V., a clinical stage biotech company focused on developing novel treatments for neurodegenerative and neurodevelopmental disorders, has passed the milestone of 50% enrollment in its pivotal phase 3 Huntington’s Disease (HD - PROOF-HD) trial.

The trial is investigating Prilenia’s lead candidate, pridopidine, for treatment of Huntington’s Disease. The study reached 25% in May 2021 and enrolled a further 25% in only six weeks, with now over 240 registered early-stage HD patients. There have been no drop-outs, and no safety concerns to date.

The PROOF-HD clinical trial is enrolling patients across 60 sites in Europe and North America, in collaboration with the Huntington’s Study Group (HSG). It was organized and initiated in record time, despite the COVID-19 pandemic and is currently the most advanced clinical trial in this indication.

Dr. Michael R. Hayden, CEO and Founder of Prilenia, commented:We are delighted that despite the challenging circumstances of the past year, our pivotal Phase 3 study in HD continues as planned, reaching such a significant milestone in a short time. At our current pace, we will be able to complete enrollment ahead of schedule.”

Dr. Andrew Feign, MD, North American Principal Investigator for the PROOF-HD Phase 3 trial, added: “Rapidly achieving 50% enrolment shows great momentum as we push forward with recruitment for this Phase 3 clinical trial. This is exciting not only for Prilenia, but for the full HD research field.”


Notes to Editors

About Prilenia

Prilenia is a clinical stage biotech startup founded in 2018 with the purpose of improving the lives of patients and their families by developing treatments for neurodegenerative and neurodevelopmental disorders. Prilenia raised $ 90.5 million thus far and is backed by a group of well-respected investors: Forbion, Morningside, Sectoral, Talisman, and ALS Investment Fund. The Company is based in Naarden, the Netherlands, Herzliya, Israel and Boston, MA in the U.S.

For more information visit and follow us on twitter @prileniaTx.

About Pridopidine

Prilenia’s lead asset is Pridopidine, a first-in-class, highly selective S1R agonist investigational drug . Pridopidine has an established safety profile and therapeutic potential in several neurodegenerative diseases, affecting adults and children. Pridopidine was acquired from Teva in 2018.


PROOF-HD is a Phase 3, randomized, double-blind, placebo-controlled study evaluating the effect of pridopidine on functional capacity in early-stage HD patients. It builds on the long-standing favorable tolerability and safety profile, concluded in previous studies with pridopidine, including PRIDE-HD.

For more information about PROOF-HD, including inquiries regarding participation, please visit the study’s website:


Prilenia Therapeutics
Limor Ben Har, COO

Instinctif Partners
Melanie Toyne-Sewell / Agnes Stephens / Siobhan Sanford / Eddie Waller
T: +44 (0) 207 457 2020


Source: Prilenia Therapeutics

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