Final Analysis Show Johnson & Johnson's COVID-19 Offers Only 52.9% Protection

Scientists have revealed data from their final analysis of Johnson & Johnson's JNJ COVID-19 Phase 3 study, showing the vaccine may be even less effective in the longer term.

• The scientists tracked about 39,000 participants for a median of four months (8,940 of whom had at least six months of follow-up), researchers concluded in a paper published in the New England Journal of Medicine.
• Data showed that a single dose of Ad26.COV2.S provided 52.9% protection against moderate to severe–critical COVID-19. 
• Protection varied according to variant; higher protection was observed against severe COVID-19, medical intervention, and death than against other endpoints and lasted for six months or longer.
• Related: Johnson & Johnson Halts Production Of Its COVID-19 Vaccine: NYT.
• Looking at least 28 days after administration, 3 COVID-19–related deaths occurred in the vaccine group compared with 17 in the placebo group.
• The scientists noted that the original strain of SARS-CoV-2 and variants like Alpha, Beta, and Lambda were responsible for many infections and severe cases. In contrast, Delta and Omicron were not prevalent during the double-blind.
• Ad26.COV2.S vaccine (Johnson & Johnson–Janssen) is a recombinant, replication-incompetent human adenovirus type 26 (Ad26) vector encoding a full-length, membrane-bound severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein.
• Price Action: JNJ shares are down 1.07% at $169.66 during the market session on the last check Thursday.