• VG901 is the first-in-class and only clinical-stage therapy designed to deliver
the functional CNGA1 gene intravitreally (IVT) to target retinal photoreceptor
cells in patients with retinitis pigmentosa
• FDA Rare Pediatric Disease Designation qualifies ViGeneron for potential
eligibility for a Priority Review Voucher (PRV) upon marketing approval
• The independent Data Safety Monitoring Board (DSMB) unanimously approved
dose escalation in VG901’s ongoing Phase 1b clinical trial

Munich, Germany, January 8, 2025 –– ViGeneron GmbH, a next-generation clinical-stage
gene therapy company, today announced two important milestones for its novel gene therapy
candidate VG901, to treat patients with retinitis pigmentosa (RP) caused by mutations in the
CNGA1 gene. The U.S. Food and Drug Administration (FDA) has granted Rare Pediatric
Disease Designation (RPDD) to VG901, and the independent Data Safety Monitoring Board
(DSMB) has unanimously approved dose escalation in the ongoing Phase 1b clinical trial.
The FDA’s RPDD acknowledges the critical need for treatments addressing rare pediatric
conditions like retinitis pigmentosa caused by CNGA1 mutations. This designation qualifies
ViGeneron to potentially secure a Priority Review Voucher (PRV) upon VG901’s marketing
approval. A PRV enables accelerated FDA review of any drug candidate in the company’s
pipeline, reducing the review period to six months, and is transferable for use or sale.
“This RPDD recognition from the FDA highlights the significant unmet medical need in retinitis
pigmentosa and underscores VG901’s therapeutic potential as the first-in-class and only
clinical-stage therapy targeting retinitis pigmentosa associated with mutations in the CNGA1
gene,” said Dr. Caroline Man Xu, ViGeneron’s Co-founder and CEO. “In addition to the
previously granted FDA Orphan Drug Designation for VG901, the RPDD designation further
supports our efforts to accelerate the development of VG901.”
The ongoing Phase 1b trial is designed to evaluate the safety and preliminary efficacy of
VG901, which leverages ViGeneron’s novel next-generation vgAAV capsid to deliver the
functional CNGA1 gene to retinal photoreceptor cells via intravitreal injection. The DSMB,
composed of independent experts, conducts a rigorous evaluation of trial data after each
cohort of patients.
“The DSMB has unanimously recommended proceeding with dose escalation in the ongoing
VG901 Phase 1b clinical trial,” commented Dr. Bart P Leroy, Ophthalmologist & Clinical
Geneticist, Head of Department of Ophthalmology, Ghent University Hospital, Belgium, and
the DSMB Chair for this trial. “No dose-limiting adverse events related to VG901 have been
reported in the first-dose cohort to date. This marks a critical step toward advancing to the
higher dose and represents an important milestone in its clinical development.”

About Retinitis Pigmentosa (RP) and VG901
Retinitis pigmentosa (RP) is a group of related eye disorders that cause progressive vision
loss. RP initially presents as nighttime blindness during childhood or early adulthood,
progressing to peripheral visual field loss and “tunnel vision”, central visual impairment,
reduced visual acuity, and ultimately, complete blindness. Retinitis pigmentosa is the most
common type of inherited retinal diseases (IRDs). It is estimated to affect 1 in 3,500 to 1 in
4,000 people in the United States and Europe, respectively. Mutations in the CNGA1 gene,
encoding a subunit of CNG channels in rod photoreceptors, are reported to cause
approximately 2%–8% of autosomal recessive retinitis pigmentosa (arRP).
VG901 is a first-in-class and only clinical-stage gene therapy to treat CNGA1-associated
Retinitis Pigmentosa (RP). The therapy approach utilizes vgAAV, ViGeneron’s novel
proprietary adeno-associated virus (AAV) vector, to deliver the CNGA1 gene via intravitreal
injection. VG901 has demonstrated in vivo functionality by delivering the CNGA1 gene in a
mouse model, while a GLP safety study with a six-month observation period confirmed its
safety, durable expression, and sustained tolerability. VG901 is currently in a Phase 1b clinical
trial, an open-label, single-arm, dose-escalation study assessing the safety, tolerability, and
preliminary efficacy of a one-time intravitreal administration of VG901.

About ViGeneron GmbH
ViGeneron is dedicated to bringing gene therapy innovations to people in need. The company
is advancing its proprietary, clinical-stage gene therapy pipeline to treat ophthalmic diseases,
while partnering with leading biopharmaceutical players in retinal diseases, CNS,
cardiovascular and other disease areas. ViGeneron’s three novel next-generation gene
therapy platforms are geared towards addressing the limitations of existing adeno-associated
virus (AAV)-based gene therapies. The first, the vgAAV vector platform, enables a superior
transduction efficiency of target cells and is designed to overcome biological barriers, thus
enabling novel, less invasive routes of administration such as intravitreal and systemic
administration. The second, the REVeRT (REconstitution Via mRNA Trans-splicing)
technology platform, allows for efficient reconstitution of large genes (>5kb) in any tissue that
can be targeted with a given capsid. The third, the AAV Transactivation is a CRISPR-Cas–
based AAV gene therapy platform that enables the regulation of one or multiple genes in vivo
by increasing or inhibiting their expression. Privately-owned ViGeneron was founded in 2017
by a seasoned team with in-depth experience in AAV vector technology and clinical ophthalmic
gene therapy programs and is located in Munich, Germany. For further information, please
visit www.vigeneron.com.