In elderly patients, the 13-valent pneumococcal conjugate vaccine was not associated with increased risk for adverse events compared with the older, 23-valent pneumococcal conjugate vaccine — a finding that supports its ongoing use, according to researchers.
In 2015, the CDC’s Advisory Committee on Immunization Practices recommended that the PCV13 and PPSV23 vaccines be administered routinely in a series to all adults aged 65 years or older, spaced at least 1 year apart, to prevent invasive pneumococcal disease (IPD). Although clinical trials have shown no association between PCV13 and serious adverse events, researchers said post-licensure studies are needed to assess its “real-world safety in a larger population.”
In a retrospective cohort study, Hung Fu Tseng, PhD, a research scientist at Kaiser Permanente Southern California, and colleagues searched for evidence of an increased risk for adverse events requiring medical attention in seniors who received either PCV13 or PPSV23. They identified members of six managed care organizations involved in the Vaccine Safety Datalink project and compared rates of adverse events among those who received PCV13 from Jan. 1, 2001, to Aug. 15, 2015, with those of seniors who received PPSV23 from Jan. 1 to Aug. 15 of each year between 2011 and 2015.
A total of 313,136 doses of PCV13 and 232,591 doses of PPSV23 were administered over the course of the study.
In unadjusted analyses, the PCV13 group demonstrated a significantly higher risk of atrial fibrillation and significantly lower risks of syncope, thrombocytopenia and allergic reaction.
Adjusted analyses revealed no significantly increased risk in the PCV13 group for any prespecified events. Except for anaphylaxis, which was insignificant with an RR of 1.32 (95% CI, 0.30-5.79), the adjusted RRs comparing the prevalence of adverse events after PCV13 vs. PPSV23 were all less than 1.
Diagnoses of anaphylaxis were chart-reviewed; five of these occurred after PCV13, and four followed PPSV23. Eight of these nine cases were codes for historical events, with only one confirmed as occurring after vaccination. This patient, who was part of the PCV13 cohort, had also been administered four other vaccines concomitantly; these included vaccines for hepatitis A, hepatitis B, tetanus, diphtheria, pertussis and typhoid.
“We found no evidence of increased risks of adverse events requiring medical attention following vaccination with PCV13 as compared to vaccination with PPSV23 in adults age 65 and older,” the researchers wrote. “PPSV23 has a well-established safety profile. As unconjugated polysaccharide vaccines likely do not confer long-lasting protection, and the incidence of IPD among adults increases dramatically with age, PCV13 has the advantage of offering higher levels of protection against the vaccine serotypes after vaccination and the ability to prolong the duration of protection in elderly adults, with no apparent increase in safety concerns.” – by Jennifer Byrne
Disclosures: Tseng reports receiving research support from Novartis Vaccines, GlaxoSmithKline and Novavax for studies unrelated to this study. Please see the study for all other authors’ relevant financial disclosures.