Myrtelle, Inc.

Analysis of Cerebral Spinal Fluid (CSF) from patients at pre-treatment baseline to post-treatment intervals up to 24 months demonstrates marked decrease in N-Acetylaspartate (NAA) Magnetic Resonance Imaging (MRI) assessments also show increases in brain white matter and myelin volume as well as functional improvements on validated scales The NAA reduction, MRI assessments and encouraging efficacy and safety data support further development of rAAV-Olig001-ASPA and discussions with regulatory authorities for a potential road map to registration NEW YORK, NY, USA I October 10, 2024 I Myrtelle Inc. (“Myrtelle” or the “Company”), a gene therapy company focused on developing transformative treatments for neurodegenerative diseases, today announced clinical trial findings showing a significant biomarker change in patients treated with the Company’s investigational gene therapy for Canavan disease (CD), rAAV-Oligo001-ASPA. Analysis of Cerebral Spinal Fluid (CSF) from seven patients, observed up to 24-month post treatment milestone revealed that each patient demonstrated a decrease of over 80% in N-Acetylaspartate (NAA) from their baseline measurement. Observations of these patients using Magnetic Resonance Imaging (MRI) also demonstrated increases in brain white matter and myelin volume over the same time intervals. The Company’s open-label Phase 1/2 First-in-Human (FIH) clinical trial is being conducted at Dayton Children’s Hospital (Dayton, Ohio) and includes baseline and post treatment assessments at 1, 3, 6, and 12 months the first year after surgery, and then once every 12 months for 5 years. Myrtelle’s FIH trial utilizes the Company’s proprietary rAAV vector to directly target oligodendrocytes, the brain cells affected in CD which are responsible for producing myelin – the insulating material that enables proper neuronal function. In CD, the production of myelin is impaired due to a mutation in the Aspartoacylase gene ( ASPA) that encodes the enzyme Aspartoacylase (ASPA) which is expressed in the brain solely in oligodendrocytes. The deficiency of ASPA enzyme results in multiple biochemical and anatomic changes, including inability to metabolize N-Acetylaspartate (NAA), a neurochemical that is abundant in the brain and plays an important role in myelin synthesis and brain bioenergetics. Myrtelle’s novel oligodendrocyte-targeting rAAV vector-based gene therapy is intended to restore ASPA function and hence the metabolism of NAA and myelination in patients with CD. Patients have also shown functional improvements on validated functional scales. Observed improvements in these treated patients are in contrast to the continuous clinical deterioration expected with the natural progression of CD. “The combination of changes in NAA levels and myelin volume offers a valuable tool for assessing early therapeutic efficacy in Canavan disease. Improvement in such important disease markers like NAA and myelin, together with functional gains in our patients, is encouraging given the progressive nature of Canavan disease. It drives us to continue our work to bring this potentially important therapy to the patients who currently do not have treatment options,” commented Olga Flamini, Co-CMO at Myrtelle. Myrtelle recently announced that rAAV-Olig001-ASPA was selected by the FDA for participation in the START pilot program in which the gene therapy candidate was one of four CBER-regulated products chosen. rAAV-Olig001-ASPA has also received RMAT, Orphan Drug, Rare Pediatric Disease, and Fast Track designations from the FDA, Orphan Drug Designation & Advanced Therapy Medicinal Product (ATMP) classification from the European Medicines Agency, as well as Innovative Licensing and Access Pathway (ILAP) from the United Kingdom Medicines & Healthcare products Regulatory Agency. ABOUT MYRTELLE Myrtelle Inc. is a gene therapy company focused on developing transformative treatments for neurodegenerative diseases. The company has a proprietary platform, intellectual property, and portfolio of programs and technologies supporting innovative gene therapy approaches for neurodegenerative diseases. Myrtelle has an exclusive worldwide licensing agreement with Pfizer Inc. for its Canavan disease program. For more information, please visit the Company’s website at: www.myrtellegtx.com . ABOUT CANAVAN DISEASE Canavan disease (CD) is a fatal childhood genetic brain disease caused by mutations in the ASPA gene ( ASPA ) which prevent the normal expression of aspartoacylase, a critical enzyme produced in oligodendrocytes. The lack of normal aspartoacylase expression negatively impacts brain bioenergetics and development, including myelin production. Patients with CD are impacted at birth but may appear normal until several months old when symptoms begin to develop. Poor head control, abnormally large head size, difficulty in eye tracking, excessive irritability, severely diminished muscle tone, and delays in reaching motor milestones, such as rolling, sitting, and walking, are the typical initial manifestations of CD. As the disease progresses, seizures, spasticity, difficulties in swallowing, and overall muscle deterioration emerge with most affected children developing life-threatening complications by approximately 10 years of age. Currently, there are no cures for CD, and only palliative treatments are available. More information on Myrtelle’s clinical trial in Canavan disease can be found on https://clinicaltrials.gov/ under the identifier NCT04833907 or by emailing PatientAdvocacy@MyrtelleGTX.com . SOURCE: Myrtelle

Analysis of Cerebral Spinal Fluid (CSF) from patients at pre-treatment baseline to post-treatment intervals up to 24 months demonstrates marked decrease in N-Acetylaspartate (NAA) Magnetic Resonance Imaging (MRI) assessments also show increases in brain white matter and myelin volume as well as functional improvements on validated scales The NAA reduction, MRI assessments and encouraging efficacy and safety data support further development of rAAV-Olig001-ASPA and discussions with regulatory authorities for a potential road map to registration NEW YORK, NY, USA I October 1, 2024 I Myrtelle Inc. (“Myrtelle” or the “Company”), a gene therapy company focused on developing transformative treatments for neurodegenerative diseases, today announced clinical trial findings showing a significant biomarker change in patients treated with the Company’s investigational gene therapy for Canavan disease (CD), rAAV-Oligo001-ASPA. Analysis of Cerebral Spinal Fluid (CSF) from seven patients, observed up to 24-month post treatment milestone revealed that each patient demonstrated a decrease of over 80% in N-Acetylaspartate (NAA) from their baseline measurement. Observations of these patients using Magnetic Resonance Imaging (MRI) also demonstrated increases in brain white matter and myelin volume over the same time intervals. The Company’s open-label Phase 1/2 First-in-Human (FIH) clinical trial is being conducted at Dayton Children’s Hospital (Dayton, Ohio) and includes baseline and post treatment assessments at 1, 3, 6, and 12 months the first year after surgery, and then once every 12 months for 5 years. Myrtelle’s FIH trial utilizes the Company’s proprietary rAAV vector to directly target oligodendrocytes, the brain cells affected in CD which are responsible for producing myelin – the insulating material that enables proper neuronal function. In CD, the production of myelin is impaired due to a mutation in the Aspartoacylase gene ( ASPA) that encodes the enzyme Aspartoacylase (ASPA) which is expressed in the brain solely in oligodendrocytes. The deficiency of ASPA enzyme results in multiple biochemical and anatomic changes, including inability to metabolize N-Acetylaspartate (NAA), a neurochemical that is abundant in the brain and plays an important role in myelin synthesis and brain bioenergetics. Myrtelle’s novel oligodendrocyte-targeting rAAV vector-based gene therapy is intended to restore ASPA function and hence the metabolism of NAA and myelination in patients with CD. Patients have also shown functional improvements on validated functional scales. Observed improvements in these treated patients are in contrast to the continuous clinical deterioration expected with the natural progression of CD. “The combination of changes in NAA levels and myelin volume offers a valuable tool for assessing early therapeutic efficacy in Canavan disease. Improvement in such important disease markers like NAA and myelin, together with functional gains in our patients, is encouraging given the progressive nature of Canavan disease. It drives us to continue our work to bring this potentially important therapy to the patients who currently do not have treatment options,” commented Olga Flamini, Co-CMO at Myrtelle. Myrtelle recently announced that rAAV-Olig001-ASPA was selected by the FDA for participation in the START pilot program in which the gene therapy candidate was one of four CBER-regulated products chosen. rAAV-Olig001-ASPA has also received RMAT, Orphan Drug, Rare Pediatric Disease, and Fast Track designations from the FDA, Orphan Drug Designation & Advanced Therapy Medicinal Product (ATMP) classification from the European Medicines Agency, as well as Innovative Licensing and Access Pathway (ILAP) from the United Kingdom Medicines & Healthcare products Regulatory Agency. ABOUT MYRTELLE Myrtelle Inc. is a gene therapy company focused on developing transformative treatments for neurodegenerative diseases. The company has a proprietary platform, intellectual property, and portfolio of programs and technologies supporting innovative gene therapy approaches for neurodegenerative diseases. Myrtelle has an exclusive worldwide licensing agreement with Pfizer Inc. for its Canavan disease program. For more information, please visit the Company’s website at: www.myrtellegtx.com . ABOUT CANAVAN DISEASE Canavan disease (CD) is a fatal childhood genetic brain disease caused by mutations in the ASPA gene ( ASPA ) which prevent the normal expression of aspartoacylase, a critical enzyme produced in oligodendrocytes. The lack of normal aspartoacylase expression negatively impacts brain bioenergetics and development, including myelin production. Patients with CD are impacted at birth but may appear normal until several months old when symptoms begin to develop. Poor head control, abnormally large head size, difficulty in eye tracking, excessive irritability, severely diminished muscle tone, and delays in reaching motor milestones, such as rolling, sitting, and walking, are the typical initial manifestations of CD. As the disease progresses, seizures, spasticity, difficulties in swallowing, and overall muscle deterioration emerge with most affected children developing life-threatening complications by approximately 10 years of age. Currently, there are no cures for CD, and only palliative treatments are available. More information on Myrtelle’s clinical trial in Canavan disease can be found on https://clinicaltrials.gov/ under the identifier NCT04833907 or by emailing PatientAdvocacy@MyrtelleGTX.com . SOURCE: Myrtelle

Analysis of Cerebral Spinal Fluid (CSF) from patients at pre-treatment baseline to post-treatment intervals up to 24 months demonstrates marked decrease in N-Acetylaspartate (NAA) Magnetic Resonance Imaging (MRI) assessments also show increases in brain white matter and myelin volume as well as functional improvements on validated scales The NAA reduction, MRI assessments and encouraging efficacy and safety data support further development of rAAV-Olig001-ASPA and discussions with regulatory authorities for a potential road map to registration New York, NY, October 1st, 2024 – Myrtelle Inc. (“Myrtelle” or the “Company”), a gene therapy company focused on developing transformative treatments for neurodegenerative diseases, today announced clinical trial findings showing a significant biomarker change in patients treated with the Company’s investigational gene therapy for Canavan disease (CD), rAAV-Oligo001-ASPA. Analysis of Cerebral Spinal Fluid (CSF) from seven patients, observed up to 24-month post treatment milestone revealed that each patient demonstrated a decrease of over 80% in N-Acetylaspartate (NAA) from their baseline measurement. Observations of these patients using Magnetic Resonance Imaging (MRI) also demonstrated increases in brain white matter and myelin volume over the same time intervals. The Company’s open-label Phase 1/2 First-in-Human (FIH) clinical trial is being conducted at Dayton Children’s Hospital (Dayton, Ohio) and includes baseline and post treatment assessments at 1, 3, 6, and 12 months the first year after surgery, and then once every 12 months for 5 years. Myrtelle’s FIH trial utilizes the Company’s proprietary rAAV vector to directly target oligodendrocytes, the brain cells affected in CD which are responsible for producing myelin – the insulating material that enables proper neuronal function. In CD, the production of myelin is impaired due to a mutation in the Aspartoacylase gene (ASPA) that encodes the enzyme Aspartoacylase (ASPA) which is expressed in the brain solely in oligodendrocytes. The deficiency of ASPA enzyme results in multiple biochemical and anatomic changes, including inability to metabolize N-Acetylaspartate (NAA), a neurochemical that is abundant in the brain and plays an important role in myelin synthesis and brain bioenergetics. Myrtelle’s novel oligodendrocyte-targeting rAAV vector-based gene therapy is intended to restore ASPA function and hence the metabolism of NAA and myelination in patients with CD. Patients have also shown functional improvements on validated functional scales. Observed improvements in these treated patients are in contrast to the continuous clinical deterioration expected with the natural progression of CD. “The combination of changes in NAA levels and myelin volume offers a valuable tool for assessing early therapeutic efficacy in Canavan disease. Improvement in such important disease markers like NAA and myelin, together with functional gains in our patients, is encouraging given the progressive nature of Canavan disease. It drives us to continue our work to bring this potentially important therapy to the patients who currently do not have treatment options,” commented Olga Flamini, Co-CMO at Myrtelle. Myrtelle recently announced that rAAV-Olig001-ASPA was selected by the FDA for participation in the START pilot program in which the gene therapy candidate was one of four CBER-regulated products chosen. rAAV-Olig001-ASPA has also received RMAT, Orphan Drug, Rare Pediatric Disease, and Fast Track designations from the FDA, Orphan Drug Designation & Advanced Therapy Medicinal Product (ATMP) classification from the European Medicines Agency, as well as Innovative Licensing and Access Pathway (ILAP) from the United Kingdom Medicines & Healthcare products Regulatory Agency. ABOUT MYRTELLE Myrtelle Inc. is a gene therapy company focused on developing transformative treatments for neurodegenerative diseases. The company has a proprietary platform, intellectual property, and portfolio of programs and technologies supporting innovative gene therapy approaches for neurodegenerative diseases. Myrtelle has an exclusive worldwide licensing agreement with Pfizer Inc. for its Canavan disease program. For more information, please visit the Company’s website at: www.myrtellegtx.com. ABOUT CANAVAN DISEASE Canavan disease (CD) is a fatal childhood genetic brain disease caused by mutations in the ASPA gene (ASPA) which prevent the normal expression of aspartoacylase, a critical enzyme produced in oligodendrocytes. The lack of normal aspartoacylase expression negatively impacts brain bioenergetics and development, including myelin production. Patients with CD are impacted at birth but may appear normal until several months old when symptoms begin to develop. Poor head control, abnormally large head size, difficulty in eye tracking, excessive irritability, severely diminished muscle tone, and delays in reaching motor milestones, such as rolling, sitting, and walking, are the typical initial manifestations of CD. As the disease progresses, seizures, spasticity, difficulties in swallowing, and overall muscle deterioration emerge with most affected children developing life-threatening complications by approximately 10 years of age. Currently, there are no cures for CD, and only palliative treatments are available. More information on Myrtelle’s clinical trial in Canavan disease can be found on https://clinicaltrials.gov/ under the identifier NCT04833907 or by emailing PatientAdvocacy@MyrtelleGTX.com. Forward-Looking Statements This press release contains forward-looking statements. Words such as “may,” “believe,” “will,” “expect,” “plan,” “anticipate,” “estimate,” “intend” and similar expressions (as well as other words or expressions referencing future events, conditions or circumstances) are intended to identify forward-looking statements. Forward-looking statements are based upon current estimates and assumptions and include statements regarding Myrtelle’s novel oligodendrocyte-targeting rAAV vector-based gene therapy restoring ASPA, the combination of changes in NAA levels and myelin volume offering a valuable tool for assessing early therapeutic efficacy in Canavan disease and Myrtelle continuing its work to bring this potentially important therapy to the patients who currently do not have treatment options. While Myrtelle believes these forward-looking statements are reasonable, undue reliance should not be placed on any such forward-looking statements, which are based in information available to us on the date of this release. These forward-looking statements are subject to various risks and uncertainties, many of which are difficult to predict, that could cause actual results to differ materially from current expectations and assumptions from those set forth or implied by any forward-looking statements. Important factors that could cause actual results to differ materially from current expectations include, among others, Myrtelle’s program demonstrating safety and efficacy, as well as results that are consistent with prior results, the ability to generate the data needed for further development of this novel gene therapy in the patients with CD, and the ability to continue its trials and to complete them on time and achieve the desired results. All forward-looking statements are based on Myrtelle’s expectations and assumptions as of the date of this press release. Actual results may differ materially from these forward-looking statements. Except as required by law, Myrtelle expressly disclaims any responsibility to update any forward-looking statement contained herein, whether as a result of new information, future events or otherwise. Media Contact: Jordana Holovach Head of Communications and Community Myrtelle Inc. 914-673-2796 jholovach@myrtellegtx.com