Avidity begins Cohort C enrollment in FORTITUDE trial

Avidity begins Cohort C enrollment in FORTITUDE trial

Avidity Biosciences has begun enrollment of Cohort C of the Phase 1/2 FORTITUDE™ clinical trial. Below is Avidity’s letter to the FSHD community and their answers to some FAQs:

October 30, 2024

We are very pleased to share with you that we have initiated a biomarker cohort in the Phase 1/2 FORTITUDE™ clinical trial, which is assessing the safety and efficacy of our investigational therapy delpacibart braxlosiran (formerly AOC 1020, abbreviated as del-brax) in people living with facioscapulohumeral muscular dystrophy (FSHD).

The biomarker cohort in the FORTITUDE trial will assess del-brax (2 mg/kg) administered every six weeks in people living with FSHD, ages 16-70 and will be measuring changes in DUX4 regulated biomarkers. To learn more about the study, please visit the FORTITUDE study website or go to the following link: clinicaltrials.gov.

You can view our full press release of today’s FSHD news here:

Avidity Biosciences Pursues Potential Accelerated Approval Path with Initiation of Biomarker Cohort in FORTITUDE™ Trial for Delpacibart Braxlosiran (del-brax/AOC 1020) in People Living with Facioscapulohumeral Muscular Dystrophy click here to learn more.

Screening is now underway for the biomarker cohort (Cohort C) and we expect enrollment to be completed in the first half of 2025. The biomarker cohort will be conducted in the US, Canada, and the UK (same as Cohorts A and B).

At this point, we have received tremendous interest from participants to be screened for the FORTITUDE trial. Our team is moving rapidly to complete this study as we know we have more patients waiting than we can accommodate in this trial.

We anticipate the initiation of a larger functional cohort of the FORTITUDE trial to begin in the first half of 2025. Patients who have participated in a trial not conducted by Avidity may be eligible for the larger functional cohort. Due to inclusion and exclusion criteria, you would still need to undergo screening assessments to determine if you are eligible.

We are advancing our clinical studies for del-brax as quickly as possible as we understand the urgency to bring a potential new treatment to people living with FSHD.

We want to thank the entire patient community for your time, commitment and continued

contributions to the development of del-brax. We are so grateful to the current and future participants, their families, the investigators and their teams as we work together to advance del-brax in clinical development.

We encourage you to contact your doctor if you have any questions about del-brax or the FORTITUDE trial.

Sincerely,

The Avidity Team

FAQs

When and where will you be screening participants for Cohort C?

Screening is currently underway for Cohort C (biomarker cohort) and participants will begin enrolling (dosing) before the end of this year (2024). Cohort C will be conducted in the US, Canada, and the UK (same as Parts A and B). Our functional cohort will be larger than previous cohorts in terms of number of patients, sites and country footprint. We anticipate initiation of this to begin the first half of 2025. We have not yet finalized countries but anticipate we would expand beyond our current footprint.

I am anxious to enter this study, why weren’t additional sites added?

We did not add additional sites for Cohort C due to the long lead times required to bring them into the study. To get this cohort up and running as quickly as possibly we decided to use existing sites.

What is the age range of participants?

In Cohort C (biomarker cohort), we have expanded the participant age range to 16 to 70 years. For cohorts A and B it was 18-65.

How many participants do you expect to enroll?

In Cohort C (biomarker cohort), our goal is to enroll up to 48 participants randomized to study drug or placebo, 2:1

What is the dose regimen?

Participants will be at 2mg/kg approximately every 6 weeks

How can I enter this Cohort?

We do expect there to be more interest in participation in the remaining Cohorts for FORTITUDE than we can accommodate. We anticipate having a larger functional cohort. If you have any questions regarding enrollment, please reach out to the trial sites directly by visiting the FORTITUDE trial website https://fortitude-study.com/ or http://www.clinicaltrials.gov and search for NCT05747924

What is different about Cohort C?

• There are fewer study visits than in Cohorts A & B
• There are fewer MRIs required than Cohorts A & B
• Dosing is more frequent in Cohort C (twice quarterly) than in Cohorts A & B (once quarterly)
• The participant age range has been expanded to 16 to 70 years of age for Cohort C

What countries will you be conducting in the biomarker cohort and functional cohort in?  

The biomarker cohort will be conducted in the US, Canada, and the UK (same as Parts A and B). You can view these locations on clinicaltrials.gov . We have not yet finalized the countries for the functional cohort  but anticipate that we would include additional countries.

Do you know when you will file for approval?

It is too early too speculate about a potential approval, with this data comes the responsibility to move as thoughtfully —  and as quickly —  as we can toward approval but we still have continuous engagement with FDA about a path forward.

I participated in other trials for FSHD am I eligible to participate in FORTITUDE?

Thank you for your interest in participating in FORTITUDE, we expect there to be more interest in participation for FORTITUDE than we can accommodate. Patients who have participated in a trial not conducted by Avidity may be eligible for the larger functional cohort. Due to inclusion and exclusion criteria, you would still need to undergo screening assessments to determine if you are eligible.