N Engl J Med: Single-dose Ad26.COV2.S Efficacy and Safety Final Analysis

The Ad26.
COV2.
S vaccine (Johnson & Johnson–Janssen) is a recombinant, replication-deficient human adenovirus type 26 (Ad26) vector-encoded full-length, membrane-bound SARS-CoV-2 spike protein
.

We performed our final analysis in the double-blind phase of a multinational, randomized, placebo-controlled trial in which adults were assigned in a 1:1 ratio to receive a single dose of Ad26.
COV2.
S (5 × 10 ¹⁰ viral particles) or placebo
.

Experimental results:

Median follow-up for this analysis was 4 months; 8940 subjects were followed for at least 6 months
.

In the United States, the efficacy was 69.
7% (95% CI, 60.
7 to 76.
9) primarily against the reference strain (B.
1.
D614G) and the B.
1.
1.
7(α) variant;

Reduced effectiveness elsewhere against the P.
1(γ), C.
37(λ) and B.
1.
621(μ) variants
.

74.
6% efficacy in severe Covid-19 (only 4 severe cases caused by B.
1.
617.
2 [delta] variant); 75.
6% efficacy in preventing medical intervention (including hospitalization) due to Covid-19; The covid-19-related mortality was 82.
8% effective, with protection lasting 6 months or longer
.

The efficacy against any severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) infection was 41.
7%
.

Table 1: Vaccine efficacy against Covid-19 occurring at least 14 days and at least 28 days after vaccine or placebo (per-protocol risk population)

Figure 2: Cumulative incidence and vaccine efficacy of moderate-severe-critical Covid-19 over time (per-protocol population)
.

Figure 3: Vaccine efficacy against moderate-severe-critical Covid-19 according to SARS-CoV-2 lineage (per-protocol population)
.

Figure 4: Cumulative incidence of severe-critical Covid-19 and vaccine efficacy over time (per-protocol population)
.

Experimental results:

The protection rate of Ad26.
COV2.
S single-dose injection against moderate-severe-critical Covid-19 was 52.
9%
.

Original link: https://pubmed.