- The Food and Drug Administration has placed a partial clinical hold on Inovio's experimental coronavirus vaccine, suspending the planned start of late-stage testing. Invoio said the agency has "additional questions" about its Phase 2/3 trial, including the unconventional device used to deliver the vaccine into human cells.
- Inovio is one of 17 drugmakers developing a coronavirus vaccine that uses DNA to stimulate an immune response to the SARS-CoV-2 virus, and is one of four to reach human testing. However, it has since struggled to keep pace with other, faster-moving programs and has been embroiled in litigation with some of its manufacturing partners.
- The company had initially planned to begin the Phase 2/3 trial in the summer, but previously shifted the expected start of the study to September. Now the trial may begin no earlier than November. Inovio's shares tumbled 27% in morning trading.
Inovio has benefited from having a head start on many other coronavirus vaccine manufacturers. It was one of the first to begin human safety studies, an event that has helped to buoy its shares this year — even with Monday's losses, they are worth nearly four times what they were at the start of 2020.
But since disclosing preliminary study results, without specifics, from an early-stage trial in June, the company's progress has stalled. It hasn't published detailed data from the Phase 1 trial or secured outside funding to start a further test.
The partial hold initiated by the FDA represents another hurdle to overcome. In a press release, Inovio said it plans to respond to the FDA action in October, after which the agency will have 30 days to weigh in, meaning the agency might not clear the company to start testing until late November.
By then, Moderna and the partnership of Pfizer and BioNTech might have each produced enough data from their large-scale clinical trials to support emergency authorizations for their vaccines.
Inovio's vaccine is now the second to have been hit with an FDA clinical hold. Fortunately for the company, it doesn't appear to be safety related, as is the case with the shot being developed by AstraZeneca and the University of Oxford. Inovio said the FDA has "additional questions" about its vaccine and delivery device, but did not reveal more.
Inovio's vaccine INO-4800 requires a process called "electroporation," or small electrical pulses that open pores in cell walls large enough to allow the DNA plasmid to pass through. The plasmid encodes production of the coronavirus' characteristic "spike" protein with the aim of stimulating an immune response that can fight infection.
While it is unclear what questions the FDA has, Piper Sandler analyst Christopher Raymond noted that another Inovio vaccine had been subject to an eight-month delay related to a similar vaccine delivery device. "It’s not guaranteed that [Inovio] will have the all-clear from FDA to start the trial once it hears back from the agency," he wrote.
Inovio's Phase 2/3 trial will likely require around 30,000 enrollees to provide the data to support approval. The lack of external funding could create another setback to the start of the trial, Raymond wrote.
The company has also been sued by two companies, VGXI and GeneOne Life Science, that had been contracted to supply materials for its vaccine. The lawsuit is ongoing.