J&J’s Single-Dose Vaccine Nears FDA Authorization, but Appears Weakened by South African Strain

Johnson & Johnson is expected to file for Emergency Use Authorization (EUA) for its single-dose COVID-19 vaccine this week, but the much-needed shot has shown to be significantly less effective than its Pfizer/BioNTech and Moderna counterparts and looks to have problems tackling the virus’ highly contagious South African variant.

J&J has not given a specific date for submitting its EUA request, only saying that it plans to do so “in early February.” The FDA is very likely to move quickly to review the vaccine upon receiving the submission as it seeks to provide Americans with a much-needed single-dose vaccine option that would mark the third COVID-19 vaccine authorized in the U.S.

The drugmaker unveiled the interim analysis of its phase 3 trial Friday, which demonstrated that its vaccine, 28 days after administration, proved 66 percent effective overall at protecting participants against moderate-to-severe infection. The vaccine fared slightly better in U.S. participants, showing 72 percent effectiveness, while demonstrating 66 percent effectiveness in Latin American participants.

The vaccine, however, showed only 57 percent effectiveness in South African participants. The country has been the origin of a highly contagious coronavirus variant that has spread to other parts of the globe, including in the U.S., raising concerns that the variant could thwart current vaccines at a time of rising infection rates.

Anthony Fauci, director of the NIH’s National Institute of Allergy and Infectious Diseases (NIAID), cautioned against comparing the J&J vaccine’s lower efficacy rates to the highly effective rates of the Pfizer/BioNTech and Moderna vaccines. Fauci pointed out that the J&J vaccine showed 85 percent efficacy in preventing severe disease and gave complete protection against COVID-19-related hospitalization and death, including against the South African variant, an important consideration. The vaccine becomes more effective against severe disease over time and no cases in vaccinated participants were reported 49 days after inoculation, the data show.

“This really tells us that we have now a value-added additional vaccine candidate,” he said. “This has important potential and real implications both domestically and globally, [because] … this is a single-shot vaccine in which you start to see efficacy anywhere from seven to 10 days following the first and only shot,” he said.

Fauci said that J&J can produce billions of doses of the inexpensive vaccine. Should it be granted an EUA, the drugmaker will have 2 million doses of vaccine ready to ship in the U.S., according to a Government Accountability Office (GAO) report. The company has reportedly encountered manufacturing difficulties that could delay its efforts to make 12 million shots of vaccine by the end of February (DID, Jan. 14).

All of the J&J vaccine’s various efficacy rates meet the FDA’s bar of at least 50 percent efficacy for authorization, but they do pale in comparison to the near-perfect efficacies possessed by the Pfizer/BioNTech and Moderna vaccines. J&J’s vaccine still holds a significant advantage in that it uses only a single shot, simplifying distribution and administration, and can be kept at refrigerator temperatures (36 to 46 degrees Fahrenheit (F)) for at least three months.

By comparison, Pfizer/BioNTech’s vaccine must be shipped at extremely low temperatures achieved by dry ice and can only be kept at the same refrigerator temperatures for five days. Moderna’s vaccine must be transported at still cold tough less extreme temperatures and can be kept slightly longer in the refrigerator, up to 30 days. — James Miessler