Insights:Letter to the Duchenne Community: Strategic Update

Dear Duchenne Community,

In a press release issued this morning, we announced Solid’s entry into a definitive merger agreement to acquire AavantiBio, Inc., to create a genetic medicines company focused on neuromuscular and cardiac rare diseases, maintaining a strong focus on Duchenne. We want to share more context with you and what this means for the future of Solid and our programs.

Acquisition of AavantiBio

Upon closing of the merger, the combined company, which will operate as Solid Biosciences, will bring together exceptional scientists and life science leaders who are committed to patients with Duchenne and other, adjacent rare diseases. While Solid’s pipeline will include other neuromuscular and cardiac disease indications, we will carry forward our steadfast dedication to the Duchenne community and to advancing meaningful therapies. Among new leaders that will join Solid, Bo Cumbo, current President and Chief Executive Officer (CEO) of AavantiBio, will assume the role of President and CEO of Solid Biosciences at closing, succeeding Solid’s Co-Founder, President and CEO, Ilan Ganot, who will remain on Solid’s Board of Directors and as a strategic advisor to the CEO. A seasoned biotech executive, Bo shares Solid’s commitment to patients, and has gained valuable experience bringing drugs through the clinic to commercialization, and of all diseases, particularly in Duchenne. The acquisition is expected to close by the end of 2022, subject to approval by Solid’s stockholders and satisfaction of other customary closing conditions.

Many of you have met Ilan and Annie Ganot, Solid’s President and CEO and Head of Patient Advocacy, respectively. Both have been deeply involved with the Duchenne community since their son Eytani’s diagnosis in 2012. Over the past 10 years, Ilan has guided Solid Biosciences, navigating through challenges, growth and milestones, and ultimately driving Solid’s strategy toward our mission to advance meaningful treatments for patients with Duchenne.

SGT-003 and SGT-001

Today, we also announced that we have made the strategic decision to prioritize SGT-003, our next-generation adeno-associated virus (AAV) gene transfer therapy candidate that utilizes a novel, next generation capsid (AAV-SLB101), to deliver Solid’s proprietary and differentiated nNOS microdystrophin protein. We also released new SGT-003 non-clinical data which reinforced previous comparative analyses that have demonstrated increased microdystrophin expression using the novel muscle-tropic capsid AAV-SLB101 compared to AAV9. Solid remains on track for an anticipated IND submission for SGT-003 in mid-2023 with patient dosing to begin in late-2023, pending IND acceptance.

We also announced Solid will be pausing activities for its first-generation gene transfer therapy candidate SGT-001. Solid intends to complete currently ongoing SGT-001 preclinical and manufacturing activities in order to be in a position to reactive the program in the future, if desired.

Solid has continually evaluated the two programs, and believes that this is the right opportunity to put all of Solid’s Duchenne efforts behind what we believe to be a best-in-class gene therapy candidate. We will continue to follow and report data from patients who were treated in IGNITE DMD, the Phase I/II trial of SGT-001 as we believe it will continue to build on the benefit Solid’s nNOS microdystrophin can offer to patients.

We would like to express our immense gratitude for the patients and families who participated in the IGNITE DMD clinical trial, as well as all those who choose to participate in clinical trials. Your bravery and willingness provide the important foundation for advancing science and needed therapies for Duchenne.

Solid’s Exciting Future

We are excited about the potential Solid has to bring meaningful treatments to patients with Duchenne as well as other rare diseases. With a strong leadership team, dedicated scientists and rigorous science being conducted every day, Solid will be well-resourced and well-positioned for our future.

As always, we appreciate your continued support and look forward to building on our strong relationships and continuing to nurture our engagement with the Duchenne community.

Sincerely,

Your Solid Biosciences Team
#TogetherWeAreSolid

Upcoming Community Presentations

  • Action Duchenne International Conference 2022: Nov. 11-12, Leicestershire, U.K.