Inovio Pharmaceuticals, Inc., immunotherapy company, announced preliminary results from the expanded stage of its phase I study, EBOV-001. The expanded study examined different regimens of its Ebola DNA vaccine INO-4201 using intradermal (skin) administration. The results across both stages of the trial, including both intramuscular and intradermal delivery, demonstrated that 95 per cent (170/179) of evaluable subjects generated an Ebola-specific antibody immune response, with the mean antibody titer comparable or superior to those reported from viral vector-based Ebola vaccines.

Importantly, Inovio’s Ebola vaccine was well-tolerated with a favorable safety profile compared to viral vector-based Ebola vaccines, some of which have been associated with serious adverse events including myalgia, arthralgia, fever, and rash. Furthermore, their faster construct design, ability to continue to boost immune responses and protection with additional administrations, easier scalability of manufacturing, and better product thermal stability make DNA vaccines an attractive platform to rapidly respond to emerging global infectious diseases.

Previously, Inovio reported positive safety and immune response data in the first set of 75 healthy volunteers administered with INO-4212 (60 delivered intramuscularly and 15 intradermally). Based on that result Inovio enrolled an additional 125 subjects in a second stage of this trial to further characterize and optimize immunization regimens using intradermal delivery, which is well-suited for this preventive Ebola DNA vaccine. Across the two stages, 88% (50/57) of evaluable intramuscular subjects generated an Ebola-specific antibody immune response; 97% (119/122) of evaluable intradermal subjects generated an Ebola-specific antibody immune response.

In an accompanying preclinical study, INO-4201 protected 100% of rhesus monkeys challenged with a lethal dose of the Ebola virus following vaccination with two intradermal doses of INO-4201.

Dr. Scott White, Inovio’s vice president of clinical development, presented this data at the World Vaccine Congress in Washington, D.C.

Dr. J. Joseph Kim, Inovio’s president & CEO, said, “This response rate mirrors the high response rates we recently reported from our MERS and Zika clinical studies, reinforcing Inovio’s ability to rapidly design and construct vaccines against emerging global infectious diseases. With these strong results from 200 subjects and positive preliminary preclinical data from several animal species, we plan to meet with regulators this year regarding a path forward for the licensure of our Ebola product.”

Inovio’s Ebola vaccine programme is funded by a $45 million contract received from DARPA to develop an Ebola vaccine and DNA-based monoclonal antibody therapy. A more detailed data set and analysis from this study is being prepared for publishing in a peer-reviewed journal.

The Ebola virus causes periodic outbreaks of a highly contagious and lethal human infectious disease marked by severe haemorrhagic fever, with a mortality rate that ranges between 50% and 90%. The infection typically affects multiple organs in the body and is often accompanied by severe bleeding. The virus is transmitted to people from wild animals and spreads in the human population through human-to-human transmission. At present there are no FDA-approved pre- or post-exposure interventions available in the event of an outbreak, laboratory accident, or deliberate misuse. The Ebola virus is classified as a Category A Priority Pathogen by the Centers for Disease Control and Prevention. This designation prescribes an accelerated development pathway for FDA approval that determines efficacy based on two different validated animal studies followed by clinical evaluation in phase I and phase II trials to establish safety and immunogenicity for use in humans.