COVID-19 Resource Center

COVID-19 Resource Center

Issue: January 2022
Source: CDC Advisory Committee on Immunization Practices (ACIP). Accessed Dec. 16, 2021.
Disclosures: The authors report no relevant disclosures.
December 16, 2021
2 min read

ACIP recommends mRNA vaccines over J&J vaccine

Issue: January 2022
Source: CDC Advisory Committee on Immunization Practices (ACIP). Accessed Dec. 16, 2021.
Disclosures: The authors report no relevant disclosures.
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The Advisory Committee on Immunization Practices voted 15-0 in favor of a statement indicating that mRNA COVID-19 vaccines are preferred over the Johnson & Johnson COVID-19 vaccine among people aged 18 years and older.The CDC has endorsed ACIP's recommendation.

The CDC committee made the recommendation after considering new data. Specifically, they discussed a study of 54 cases of thrombosis with thrombocytopenia syndrome (TTS) following vaccination with the J&J shot, which disproportionately affected women who received it.

A woman gets vaccinated.
Source: Adobe Stock

Recent findings

Isaac See, MD, of the National Center for Emerging and Zoonotic Infectious Diseases, presented a study that examined 54 cases of thrombosis with TTS following COVID-19 vaccination with a single dose of the J&J vaccine between March 2 and Aug. 31, 2021.

Overall, 3.83 TTS cases were reported per million doses. The median age of those vaccinated was 44.5 years (range 18 to 70 years), with 37 men and 17 women. Also, 26 (48%) were women younger than the age of 50 years, and 29 (54%) of the cases had a cerebral venous sinus thrombosis (CVST).

The highest rates of TTS after the J&J vaccine occurred among women aged 30 to 39 years (n = 11; 10.6 cases per million) and among women aged 40 to 49 years (n = 10; 9.02 cases per million).

The median time from vaccination to symptom onset was 9 days (range 0 to 18 days). All the patients were hospitalized, and the median time from symptom onset to admission was 5 days (range 0 to 30 days).

Further, 36 of the patients were admitted to the ICU, with nine patients discharged to post-acute care facilities, 37 discharged home, and eight dying in the hospital.

The median age of those who died was 45 years (range 28 to 62 years), with seven women and two men. The highest rates of death included women aged 30 to 39 years (n = 2, 1.93 cases per million) and women aged 40 to 49 years (n = 2, 1.8 cases per million).

Underlying medical conditions included obesity (n = 7), hypertension (n = 3), diabetes (n = 2), iron deficiency anemia (n = 2), hypothyroidism (n = 4) and others (n = 4). All the deaths had features of severe CVST, and seven were confirmed with CVST.

Benefits and risks

Sara Oliver, MD, who leads the ACIP COVID-19 vaccines work group, presented a risk-benefit assessment and review of the J&J vaccine. Its advantages included the flexibility and choice that it offers patients, as well as its use among harder to reach populations.

Also, its effectiveness against COVID-19 hospitalization was 73% among those aged 18 to 49 years, 69% among those aged 50 to 64 years, and 76% among those aged 65 years and older, Oliver reported.

Specifically, the J&J vaccine prevented 3,729 COVID-19 hospitalizations among women aged 18 to 49 years per million doses, though it also resulted in nine hospitalizations for TTS and Guillain-Barre Syndrome (GBS).

But compared with mRNA COVID-19 vaccines, the J&J vaccine prevented fewer COVID-19 hospitalizations, ICU admissions and deaths, and it presented greater risks associated with TTS and GBS.

Oliver noted that if administration of the J&J vaccine was halted because of these risks, there would be a negative effect on supply, on access to vaccines and on confidence in vaccination, with a disproportionate impact on disadvantaged populations.

Education about these benefits and risks would aid patients, Oliver said.

When there are no alternative COVID-19 vaccines, or when mRNA vaccines are contraindicated, the benefits of the J&J vaccine outweigh its risks. But when mRNA vaccines are available, such vaccines would be preferrable to the J&J vaccine, Oliver said.

On April 13, after six cases of blood clots following vaccination were reported, the CDC and FDA recommended a pause on the J&J vaccine’s rollout. They lifted the pause on April 21.