Positive Topline Results from a Phase 3 Trial for VGX-3100 in Cervical Dysplasia Patients Announced by ApolloBio, INOVIO's Partner in China

• Results provide important clinical evidence to support ApolloBio's future regulatory submission in China of VGX-3100, INOVIO's DNA immunotherapy candidate
• ApolloBio's new clinical results further highlight the potential of INOVIO's DNA medicine platform to treat diseases caused by infection with various strains of the human papillomavirus (HPV), eliminating or reducing the need for surgical interventions

PLYMOUTH MEETING, Pa., May 21, 2026 — INOVIO (NASDAQ: INO), a biotechnology company focused on developing and commercializing DNA medicines to help treat and protect people from HPV-related diseases, cancer, and infectious diseases, today announced that its partner for VGX-3100 in China, ApolloBio, announced positive topline results from its pivotal Phase 3 trial of VGX-3100, INOVIO's investigational DNA immunotherapy being developed as a potential treatment for cervical dysplasia. The trial successfully met its predefined primary efficacy endpoint and demonstrated an overall favorable safety and tolerability profile. ApolloBio plans to use the results from the study to support a future regulatory submission of VGX-3100 in China.

"We believe these positive topline results for VGX-3100 reflect both the potential of our DNA medicine platform in HPV-related diseases and the power of partnerships to advance innovative DNA immunotherapies," said Dr. Jacqueline Shea, INOVIO's President and Chief Executive Officer. "We look forward to these data being presented at upcoming international medical conferences and published in peer-reviewed publications. We also anticipate future updates from ApolloBio as they work towards filing for potential regulatory approval of VGX-3100 in China."

According to the terms of the ApolloBio Agreement, INOVIO is entitled to receive up to an aggregate of $20.0 million, less required income, withholding or other taxes, upon the achievement of specified milestones related to the regulatory approval of VGX-3100 in specified territories. In the event that VGX-3100 is approved for marketing, INOVIO will be entitled to receive royalty payments based on a tiered percentage of annual net sales.

About VGX-3100 VGX-3100 is an innovative therapeutic DNA vaccine developed for diseases associated with high-risk human papillomavirus (HPV) types 16 and 18. VGX-3100 is designed to elicit an antigen-specific, CD8+ T cell response to clear persistent HPV 16/18 infection, thereby promoting lesion regression and viral clearance.

INOVIO licensed VGX-3100 to ApolloBio in 2018 for Greater China. ApolloBio's first intended indication for VGX-3100 is HPV-16/18-associated cervical dysplasia, with the aim of potentially providing patients in China with a non-surgical therapeutic option that may help avoid or reduce fertility-related risks associated with conventional surgical treatment (such as LEEP/conization), including preterm birth and miscarriage. ApolloBio is also advancing clinical development in other HPV-related high-grade precancerous lesions, including anal/perianal, vulvar, and vaginal disease.

About ApolloBio's Phase 3 Trial with VGX-3100 The study, sponsored by ApolloBio, is a multicenter, prospective, randomized, double-blind, placebo-controlled Phase 3 pivotal registrational clinical trial for the treatment of HPV-16/18-associated cervical high-grade squamous intraepithelial lesions (HSIL), or cervical dysplasia. The primary endpoint was the composite response rate at Week 36, defined as histopathologic regression of cervical disease to low-grade lesion (CIN1) or normal histology, together with clearance of HPV-16 and/or HPV-18 infection. The study was led by Cancer Hospital, Chinese Academy of Medical Sciences, with Professor Lingying Wu serving as the leading principal investigator. A total of 22 top-tier tertiary hospitals across China participated in the trial.

ApolloBio announced that the trial successfully met its predefined primary efficacy endpoint and demonstrated an overall favorable safety and tolerability profile, with no new significant safety risk signals observed. The positive outcome of this study provides important clinical evidence to support ApolloBio's future regulatory submission of VGX-3100 in China.

About HPV, Cervical Cancer, and Cervical Dysplasia HPV is the most common sexually transmitted infection and is the main cause of cervical cancer, which is the fourth most common cancer in women globally with around 660,000 new cases and 350,000 deaths in 2022. Two types of HPV (HPV 16 and HPV 18) collectively cause about 70 percent of cervical cancer cases worldwide. High-grade cervical dysplasia is also caused by persistent HPV infection and is a precancerous condition that can progress to cervical cancer if left untreated. Currently there are no US-approved therapeutic treatments for persistent HPV infection or cervical dysplasia.

About INOVIO's DNA Medicines Platform

INOVIO's DNA medicines platform has two innovative components: precisely designed DNA plasmids, delivered by INOVIO's proprietary investigational medical device, CELLECTRA. INOVIO uses proprietary technology to design its DNA plasmids, which are small circular DNA molecules that work like software the body's cells can download to produce specific proteins to target and fight disease. INOVIO's proprietary CELLECTRA delivery devices are designed to optimally deliver its DNA medicines to the body's cells without requiring chemical adjuvants or lipid nanoparticles and without the risk of the anti-vector response historically seen with viral vector platforms.

About INOVIO

INOVIO is a biotechnology company focused on developing and commercializing DNA medicines to help treat and protect people from HPV-related diseases, cancer, and infectious diseases. INOVIO's technology optimizes the design and delivery of innovative DNA medicines that teach the body to manufacture its own disease-fighting tools. For more information, visit www.inovio.com.

About ApolloBio ApolloBio Corp. is a leading Chinese biomedical company committed to research and development of innovative new medicines, accessing such new medicines through in-licensing, and additionally providing medical services. ApolloBio Corp. is focused on pharmaceutical products with significant market potential in China in the field of oncology; providing efficient access for American biomedical companies to enter into the Chinese market; and aiming to bring the newest and best medicines across the globe to the Chinese people. For more information, visit www.apollobio.com.