PLYMOUTH MEETING, Pa. and SEOUL, South Korea, April 28, 2020 /PRNewswire/ -- INOVIO (NASDAQ:INO) and GeneOne Life Science (KSE:011000) today announced interim data through week 16 from a Phase 1/2a trial of DNA vaccine INO-4700 (also called GLS-5300) for MERS coronavirus (MERS-CoV). Vaccine recipients demonstrated strong antibody and T cell immune responses after 2 or 3 doses with 0.6 mg of INO-4700, a DNA vaccine that targets the MERS-CoV Spike (S) glycoprotein, delivered with intradermal CELLECTRA® device. The vaccination regimen was well-tolerated with no vaccine-associated severe adverse events (SAEs). The researchers at the Wistar Institute, Seoul National University Hospital, and the International Vaccine Institute (IVI) collaborated on this study with funding from IVI. These results were selected for an oral presentation at the American Society of Gene & Cell Therapy (ASGCT) Conference to be held virtually from May 12-15, 2020.
Dr. J. Joseph Kim, INOVIO's President & CEO, said, "The INO-4700 Phase 1/2a clinical trial data demonstrates that our MERS DNA vaccine is able to generate robust immune responses using INOVIO's intradermal CELLECTRA delivery system. This exciting data provides a great foundation for the ongoing COVID-19 vaccine advancement as it demonstrates the power of INOVIO's delivery system and the strength of our coronavirus experience. As we have designed our COVID-19 vaccine INO-4800 using the same strategy as INO-4700, including the selection of full length Spike protein as the target and the use of intradermal CELLECTRA device, we are hopeful that the ongoing Phase 1 clinical trial with INO-4800 would generate similar clinical immune responses and safety data as we have just reported for INO-4700."
Overall, for those receiving 0.6 mg of INO-4700, 88% demonstrated seroconversion after a 2 dose regimen at 0 and 8 weeks, while for those receiving a 3 dose regimen given at 0, 4 and 12 weeks, 84% seroverted after 2 doses and 100% after 3 doses, as measured by a binding antibody assay against the full-length S protein (ELISA). Additionally, 92% of the vaccine recipients in both groups displayed the ability to neutralize the virus using a neutralization assay (EMC2012-Vero neutralization). Robust T cell responses were observed in 60% of vaccine recipients after the 2 dose regimen and 84% of those in the 3 dose group (ELISpot assay). Interestingly, a single dose of 0.6 mg of INO-4700 intradermal vaccination resulted in 74% binding antibody response rate and 48% neutralization antibody response rate.
Dr. Jerome Kim, Director General of IVI, said, "IVI is pleased to join partners in reporting these findings as a result of our collaboration in the world's first vaccine candidate against MERS. These and subsequent clinical trials could pave the way for accelerated development of a DNA vaccine against MERS."
This is the 2nd study of INO-4700 (GLS-5300) in a clinical trial, the first being a 75-person study (MERS-001) of vaccine administered intramuscularly and followed by electroporation at either 0.67, 2 or 6 mg. Notably in the MERS-001 study, there was no significant difference between dose levels and vaccine induced immune responses were similar to those seen in recovered patients following natural infection (Lancet Infectious Disease, 2019). INO-4700 vaccination has previously been shown to provide 100% protection against MERS virus disease in a pathogenic monkey challenge model. INOVIO is planning to advance INO-4700 into a Phase 2 clinical trial in the Middle East with a previously announced funding of $56 million by the Coalition for Epidemic Preparedness Innovations (CEPI).