Huntington’s Disease Trial of VX15/2503 (SIGNAL)

  • Study Director: Michael Geschwind, MD, PhD
  • Sponsor: Vaccinex, Inc.
  • Recruiting? No
  • Official Study Title: A Phase 2, multi-center, randomized, double-blind, placebo controlled study in subjects with late prodromal and early manifest Huntington’s disease (HD) to assess the safety, tolerability, pharmacokinetics, and efficacy of VX15/2503
  • Identifier: NCT02481674
  • Conditions Studied: Huntington’s disease (HD)
  • Intervention: VX15/2503 is a humanized IgG4 monoclonal antibody and will be administered intravenously at a dose of 20 mg/kg.
  • Duration of Participation: Approximately 18 months

Purpose of the Study

The SIGNAL trial is designed to assess the safety, tolerability, and effectiveness of VX15, a novel monoclonal antibody in people with late prodromal or early manifest Huntington’s disease (HD). It is a Phase 2, multi-center, randomized, double-blind, placebo-controlled study at 20 sites across the United States that seeks to enroll approximately 120 individuals, 21 or older, who are either early in the progression of the disease or are not yet diagnosed with the disease.

The investigational compound that will be studied in the trial is VX15, a monoclonal antibody. This is a different class of drug than any other drug used in previous HD clinical trials. Monoclonal antibodies are more specific than most other drugs because they only bind to and neutralize their desired target. Previous research suggests that VX15 may have the potential to slow the progression of brain inflammation, which has been shown to impair thinking, movement, and behavior in HD animal models.

Study Details

Inclusion Criteria: Age 21+, positive diagnosis of HD (CAG repeat greater than or equal to 36), late prodromal or early manifest HD

What to Expect


  • A screening visit to confirm eligibility. Approved subjects will complete a baseline visit and then begin the investigational period.
  • Once-a-month drug or placebo delivery through an approximately hour-long intravenous infusion
  • Brain imaging and cognitive testing during specified visits – these monthly visits may take a full day to complete
  • A single lumbar puncture for collection of cerebrospinal fluid for subjects who volunteer
  • Safety, tolerability and efficacy assessments will be performed at all visits
  • Subjects will be treated with drug or placebo intravenous infusion for 18 months.
  • A follow-up period includes a follow-up safety phone call at one month and a follow-up safety visit at three months after the final infusion

SIGNAL participants may enroll in observational studies, but they cannot participate in other clinical trials of investigational compounds. Participants may still be eligible for SIGNAL if they are taking other prescribed medications.

The Frequency of Visits


Materials Needed Before Evaluation

Medical history and CAG repeat documentation


No costs will be charged for any of the study procedures. Participants will be compensated for their travel and time.

Contact Information

If you are interested in participating in this trial or have any questions, please contact the study coordinator, Julia Glueck, at 415.502.7640 or [email protected].