for people ages 18-80 (full criteria)
at UC Irvine
study started
estimated completion
Principal Investigator
by Tahseen Mozaffar, MD (uci)
Photo of Tahseen Mozaffar
Tahseen Mozaffar



This is a phase 1/2 open-label, ascending dose, multicenter clinical study to evaluate the safety and efficacy of AT845 in adult (aged ≥ 18 years) subjects, ambulatory or nonambulatory, with Late Onset Pompe Disease (LOPD).

Official Title

A Phase 1/2, Open-Label, Ascending-Dose Clinical Study to Evaluate the Safety and Preliminary Efficacy of AT845, an AAV8-Delivered Gene Transfer Therapy in Patients With Late Onset Pompe Disease


This study (FORTIS) will evaluate the safety and efficacy of an investigational gene replacement therapy, AT845, in adult subjects with LOPD. Subjects will receive a single dose of AT845 delivered via intravenous (IV) infusion. Up to 2 nominal dose levels of AT845 are planned to be evaluated in FORTIS. A single AT845 administration via IV infusion is planned for each subject. The initial dosing cohort will receive a single dose at 3x1013 vg/kg of AT845. The second dose cohort will receive a single dose at 6x1013 vg/kg of AT845. The core observation period will be completed by Week 48 for each subject. Subjects will be followed for a total of 5 years after administration of AT845.


Pompe Disease (Late-onset) LOPD Glycogen Storage Disease Type II


You can join if…

Open to people ages 18-80

  • Subject is aged ≥ 18 years (ambulatory or nonambulatory).
  • Subject has a documented clinical diagnosis of Pompe disease by genetic testing.
  • Subject has received enzyme replacement therapy (ERT) with rhGAA for the previous ≥ 2 years.
  • Subject has been on a stable standard dose (at least 20 mg/kg every 2 weeks) of ERT with rhGAA for at least the previous 6 months.
  • Subject has upright FVC ≥ 30% of predicted normal value.
  • Subject or legally authorized representative(s) (LAR) (if applicable) provides written informed consent.
  • Subject must agree to use appropriate contraception following consent through 6 months post AT845 administration.

You CAN'T join if...

  • Subject is currently participating in an interventional study or has received gene or cell therapy.
  • Subject tests positive for AAV8 neutralizing antibodies with titers above protocol specified threshold.
  • Subject has received immune-modulating agents within 90 days before dosing (use of inhaled corticosteroids is allowed).
  • Subject tests positive for GAA total antibodies with titers above protocol specified threshold.
  • Subject has a high risk for a severe allergic reaction to rhGAA (ie, previous moderate to severe anaphylactic reaction to alglucosidase alfa or and/or a history of sustained high immunoglobulin G [IgG] antibody titers to alglucosidase alfa that in the opinion of the Investigator suggests a high risk for an allergic reaction to ERT).
  • Subject has an active viral infection based on clinical observation.
  • Subject has a history of, or currently has, a clinically important cardiac condition, such as an echocardiogram (ECHO) with ejection fraction below 40%, or has symptoms or signs of cardiomyopathy that in the opinion of the Investigator precludes enrollment.
  • Subject has a clinically significant underlying liver disease.
  • Subject has a contraindication to study drug or ingredients or to corticosteroids.


  • University of California Irvine, Department of Neurology accepting new patients
    Orange California 92868 United States
  • Stanford University accepting new patients
    Palo Alto California 94304 United States

Lead Scientist at University of California Health

  • Tahseen Mozaffar, MD (uci)
    Clinical Professor, Neurology. Authored (or co-authored) 114 research publications.


accepting new patients
Start Date
Completion Date
Audentes Therapeutics
Phase 1/2
Study Type
Last Updated