Inovio Pharmaceuticals on Tuesday said that its investigational Covid-19 vaccine had “positive” results in a small trial. But the company, which has gained more than $4 billion in value since the coronavirus pandemic began, provided none of the details necessary to determine whether the vaccine is working.
In a press release, Inovio said its vaccine led to “immunological response rates” in 34 of 36 patients in the trial, but did not disclose how many patients produced antibodies that neutralize the coronavirus — data key to determining whether the vaccine could protect against infection. The company did not immediately respond to a request for more information.
The company’s press release appeared to play down the importance of neutralizing antibodies, pointing to a study that found roughly one-third of patients who recovered from Covid-19 had no detectable antibodies in their blood.
Kathryn Edwards, scientific director of the Vanderbilt Vaccine Research Program in Nashville, Tenn., said Inovio’s vaccine appears to be safe enough to merit further study, but without more data on patient responses, it’s impossible to say whether it might have any beneficial effect.
Inovio was early to announce plans to develop a vaccine against the novel coronavirus, boosting its stock price tenfold before producing any clinical data. Its enterprise value started the year at $300 million but grew to $4.5 billion on the hope that its coronavirus vaccine work would lead to a successful product. The stock fell 13% to $27.50 in early Tuesday trading following the release of the early vaccine results.
Since the dawn of the coronavirus pandemic, drug companies have been racing to develop treatments and vaccines that might halt the global crisis. Data from clinical trials have come in dribs and drabs, often delivered by press release rather than the exhaustive, peer-reviewed research that has long been the scientific norm.
Moderna, widely considered the leader in the vaccine race, drew criticism from experts last month when it issued a press release describing its vaccine in qualitative terms rather than providing hard data. However, unlike Inovio, Moderna disclosed how many patients developed neutralizing antibodies.
Both companies have promised to publish their data in full in peer-reviewed medical journals.
Inovio’s vaccine works by injecting synthetic DNA that codes for protective antibodies, technology developed at the lab of David Weiner of the Wistar Institute in Philadelphia. Like Moderna, which uses synthetic mRNA, Inovio’s method doesn’t require administering a live virus, potentially making it faster and cheaper to manufacture.
The company said it would advance its vaccine into larger trials later this summer “upon regulatory concurrence.”
Helen Branswell contributed reporting.