April 2021

REDWOOD CITY, California, April 28, 2021 (GLOBE NEWSWIRE) – Adverum Biotechnologies, Inc. (Nasdaq: ADVM) has reported a suspected serious unexpected adverse reaction (SUSAR) of hypotonia (clinically significant minimization of eye pressure) in its INFINITY clinical trial comparing the cure of the ADVM-022 gene for the remedy of diabetic macular edema (DME). This occasion occurred 30 weeks after randomization in a patient treated with a single intravitreal injection of the height dose (6 x 10 ^ 11 vg / eye) of ADVM-022 who evolved hypotonia, with panuveitis and loss of vision in the eye. . the treated eye. In the interest of patient protection, Adverum has made the decision to promptly unmask the INFINITY Phase 2 exam to better perceive this occasion and to help identify and manage any similar potential threats to other patients on this exam, which completed the trial. of the patient in December. 2020. Additionally, the company is conducting an in-depth knowledge review of the ADVM-022 program and plans to report its findings as the investigation progresses. “Protecting each and every patient participating in our clinical trials with our genetic cure is the top sensible priority for us at Adverum,” said Laurent Fischer, M. D. , Managing Director of Advum. “We are fully committed to comparing this case very well and conducting frequent follow-up of this patient and all patients treated with ADVM-022 with our investigators, the Data Monitoring Committee (DMC), the Scientific Advisory Council and the authorities of fitness”. he is comparing two doses of a single intravitreal injection (IVT) of the ADVM-022 gene cure, either a height dose of 6 x 10 ^ 11 vg / eye or a low dose of 2 x 10 ^ 11 vg / eye . As of December 2020, the INFINITY exam was fully enrolled and all patients completed the IVT injection of ADVM-022 without marrying. All patients continue to be evaluated during the surveillance phase of this examination. Adverum works extensively with the DMC and reviews the sites to proactively expand additional recommendations for patient follow-up and All clinical trial sites, as well as the US Food and Drug Administration (FDA), have been notified of this case. About the INFINITY Phase 2 Trial of ADVM-022 in DR / DMEINFINITY is a Pha se 2, multicenter, randomized, double mask, active comparator controlled trial designed to compare a single intravitreal injection (IVT) of ADVM-022 in patients. with diabetic macular edema (DME), the non-unusual maximum cause of vision loss in patients with diabetic retinopathy (DR). The INFINITY trial recruited 36 patients and is designed to demonstrate impressive control of disease activity after an IVT injection of ADVM-022 in a single person compared to an injection of aflibercept in a single person, as measured by the time to worsening of DME disease activity. Participants in this double mask trial were randomly assigned to one of 3 arms for their eye remedy under examination: arm 1 gained a height dose (6 x 10 ^ 11 vg / eye) of ADVM-022 Array, the arm 2 gained a low dose (2 x 10 ^ 11 vg / eye) of ADVM-022 and arm 3 gained aflibercept at a 2 mg dose. Additional targets come with evaluations of processing load, visual acuity, retinal anatomy, and protection results. For more information on the INFINITY trial, visit www. clinicaltrials. gov using NCT # 04418427 or www. INFINITYclinicaltrial. com. About Advum Biotechnologies Adverum Biotechnologies (Nasdaq: ADVM) is a clinical-stage genetic curation company targeting unmet medical wishes in rare and serious eye diseases. Adverum is advancing the clinical progression of its new genetic cure candidate, ADVM-022, as an exclusive intravitreal injection for the remedy of patients with age-related rainy macular degeneration and diabetic macular edema. For more information, visit www. adverum. com. Forward-Looking Statements The statements in this press release relating to events or possibly long-term effects are “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995. Actual effects may also differ materially. than expected in those forward-looking statements due to various threats and uncertainties, which come with the threats described in the Advum Quarterly Report on Form 10-K for the fiscal year ended December 31, 2020 and any upcoming SEC filings under the heading “Risk factors”. All forward-looking statements in this press release speak only as of the date they were made. Adverum does not assume any legal responsibility to update these statements to reflect occasions that have occurred or cases that exist after the date they were made. CONTACT: Investor Relations Contacts Myesha Lacy Adverum Biotechnologies, Inc. T: 650-649-1257 E: mlacy@adverum. com Amy Figueroa Adverum Biotechnologies, Inc. T: 650-823-2704 E: afigueroa @ adverum. com Media Contact Andrea Cohen Sam Brown Inc. T: 917-209-7163 E: andreacohen@sambrown. com