Ray Therapeutics and Forge Biologics Expand Their Viral Vector cGMP Partnership to Encompass Plasmid DNA Manufacturing

Building on AAV manufacturing partnership with new plasmid production, Forge’s end-to-end manufacturing services will help to advance Ray Therapeutics’ gene therapy for patients living with retinitis pigmentosa and other blinding diseases.

Therapeutics, a biotechnology company developing optogenetic gene therapies for patients with
retinal degenerative conditions, and Forge Biologics, a gene therapy-focused contract development
and manufacturing organization, announced further collaboration for their manufacturing
partnership to include clinical stage plasmid DNA production to support Ray Therapeutics’ lead
optogenetics gene therapy program, RTx-015, in clinical trials for patients with retinitis

Forge will provide research-grade and GMP-Pathway plasmid manufacturing services, in addition
to adeno-associated viral vector (AAV) process development, scale-up engineering, and cGMP
manufacturing services for Ray Therapeutics’ program, RTx-015. The program will continue to
utilize Forge’s platform manufacturing processes, including its proprietary HEK 293 suspension
Ignition Cells™ and pEMBR™ adenovirus helper plasmid. All development and cGMP
manufacturing activities will occur at the Hearth, Forge’s 200,000 square foot gene therapy cGMP
production facility in Columbus, Ohio.

“With the recent launch of research and clinical stage plasmid DNA manufacturing, we can better
streamline the production of our clients’ AAV programs by vertically integrating plasmids into
our manufacturing process,” said Timothy J. Miller, Ph.D., CEO, President, and Co-Founder of
Forge. “Our partnership with Ray Therapeutics showcases how these new offerings can accelerate
AAV gene therapies from idea into reality for patients in need, and we are excited to help Ray
Therapeutics meet the needs of patients with retinitis pigmentosa.”

RTx-015 is intended for use in treating patients with retinitis pigmentosa (RP). Optogenetics is a
promising approach that has the potential to restore useful vision to visually-impaired and blind
individuals. Patients with RP have damaged photoreceptors, the primary cells required for vision,
which are lost and cannot regenerate. However, inner retinal neurons downstream to
photoreceptors, especially retinal ganglion cells (RGCs), persist in significant numbers through
late-stage disease. Ray Therapeutics’ lead candidate RTx-015 uses intravitreal administration,
from which the vector diffuses into the retina and transduces primarily the RGCs.

“By adding clinical grade plasmid production to their existing suite of AAV manufacturing
capabilities, Forge is easing the scope of production and accelerating the development of our lead
therapeutic,” said Paul Bresge, CEO of Ray Therapeutics. “Offering everything we need under
one roof integrates our entire process so that we can focus on our mission to restore vision in
patients losing their sight as fast as possible.”

About Retinitis Pigmentosa

Retinitis pigmentosa (RP), is a heterogeneous group of genetic diseases that cause retinal
degeneration leading to near or complete blindness for most patients. The severe loss of
photoreceptor cells that occurs in this genetic degenerative disease leads to partial or complete
blindness. At present, no effective treatment is available to restore vision once the photoreceptor
cells have been lost. Over 100 genetic mutations are known to cause RP and all types of
inheritance patterns are recognized. Patients are typically diagnosed in their late teens, with
symptoms including night blindness, reduced visual fields and eventual loss of visual acuity. As
the disease progresses, retinal atrophy, and permanent loss of the light sensitive photoreceptors
occur. The prevalence of RP is approximately 100,000 persons affected in the US.

About Ray Therapeutics

Ray Therapeutics is developing novel optogenetics gene therapies for patients with blinding
diseases. The company is developing its lead candidate RTx-015 in retinitis pigmentosa, a
degenerative retinal disease with significant unmet medical need. The company’s mission is to
use optogenetics to restore vision, independent of genetic mutation for patients with inherited
retinal diseases. Ray Therapeutics is based in San Francisco, CA. For additional information,
please visit www.raytherapeutics.com.

About Forge Biologics

Forge Biologics is a hybrid gene therapy contract manufacturing and clinical-stage therapeutics
development company. Forge’s mission is to enable access to life changing gene therapies and
help bring them from idea to reality. Forge’s 200,000 square foot facility utilizes 20 cGMP suites
in Columbus, Ohio, the Hearth, to serve as its headquarters. The Hearth is a custom-designed
cGMP facility focused on AAV manufacturing and can host end-to-end manufacturing services to
accelerate gene therapy programs from preclinical through clinical and commercial stage
manufacturing. By taking a patients-first approach, Forge aims to accelerate the timelines of these
transformative medicines for those who need them the most. To learn more, visit

Media Inquiries—Forge Biologics
Marina Corleto
Senior Manager, Marketing and Communications

Media Inquiries—Ray Therapeutics
Kimberly Ha
KKH Advisors

Client Development—Forge BiologicsJohn Maslowski
Chief Commercial Officer