Johnson & Johnson has formally asked the FDA to allow emergency use of its Covid-19 vaccine as the company seeks to add a third option to the U.S. lineup of vaccines for the novel coronavirus.
The application comes a week after J&J released preliminary data showing 66% overall efficacy in a Phase 3 clinical trial. Those results fall short of the efficacy marks of messenger RNA (mRNA) vaccines from Moderna and Pfizer. But the J&J jab offers advantages compared to those vaccines.
Unlike mRNA vaccines, which are given as two doses weeks apart, J&J’s vaccine is a single shot. Also, the J&J vaccine can be kept at refrigerator temperatures. Both the Moderna and Pfizer vaccines must be kept frozen—Pfizer’s at ultra-cold temperatures. They’re then thawed and temporarily stored at refrigerator temperatures before dosing.
J&J’s vaccine storage requirements are the same as those for most vaccines, making it an easier fit vaccine distribution channels already in place. The company said that if authorized, its vaccine will ship using the same cold chain technologies it uses for transporting other medicines. Of the vaccine candidates that have advanced to late-stage testing, J&J’s is the only one given as a single dose.
Before the FDA decides whether to grant emergency use authorization to the J&J vaccine, the pharma giant’s candidate must be evaluated by an independent advisory committee to the agency that will evaluate the clinical data and discuss the efficacy and safety risks of the shot. The vaccines from both Moderna and Pfizer went through the same step. The J&J meeting is scheduled for Feb. 26.
J&J’s vaccine, developed by the company’s Janssen division, employs a version of the virus that causes the common cold. That virus is modified so it does not cause illness. It’s used to deliver to cells a snippet of the genetic code for the spike protein, which is prominent on the surface of the novel coronavirus. The cells of the body read that genetic material and make copies of the spike protein. The immune system responds to those copies by making antibodies that protect against Covid-19.
AdVac is the same platform Janssen used to develop an Ebola vaccine that was approved by the FDA in 2019. The technology is also the foundation of experimental Zika, RSV, and HIV vaccines. J&J said that the safety profile observed with its Covid-19 vaccine was consistent with other experimental vaccines based on AdVac.
J&J evaluated its Covid-19 vaccine in a Phase 3 study enrolling 43,783 patients. The main goal was to show protection from moderate to severe disease. There were geographic differences in efficacy rates. The vaccine candidate was most protective in the U.S., where efficacy was 72%, the company said. In Latin America, efficacy was 66%; in South Africa, it was 57% effective. While those marks fell short of the efficacy rates demonstrated by the Moderna and Pfizer vaccines, cross trial comparisons are tricky. Also, the J&J studies were done when more variants of the novel coronavirus were circulating compared to when the Moderna and Pfizer vaccines were tested.
Paul Stoffels, J&J’s chief scientific officer, said in a prepared statement that the company has vaccines ready to ship immediately upon receiving emergency authorization.
“With our submission to the FDA and our ongoing reviews with other health authorities around the world, we are working with great urgency to make our investigational vaccine available to the public as quickly as possible,” he said.
In addition to the submission to the FDA, J&J is seeking similar authorizations from health agencies in other countries. The company said an application to the European Medicines Agency will be submitted in coming weeks.
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