Low Immunogenicity of Polysaccharide Pneumococcal Vaccine in SLE

The 23-valent pneumococcal polysaccharide vaccine (PPSV23) was reported to have decreased immunogenicity in adult patients with systemic lupus erythematosus (SLE), according to research published in Lupus.  

Furthermore, there were no significant differences in serotype-specific vaccine response rates found in SLE study participants receiving certain immunosuppressive medications compared with those who were not.

Patients with SLE have an increased risk of contracting serious infections, including pneumococcal infections, in part due to the effects of immunosuppressive agents and corticosteroids.  Questions regarding the immunogenicity of vaccines and the resulting effective antibody titers in patients with SLE have arisen, especially in patients receiving immunosuppression.

To examine the immunogenicity of the PPSV23 vaccine in patients with SLE, Rodrigo Poubel Vieira de Rezende, MD, of the Hospital Universitario Pedro Ernesto, Rio de Janiero, Brazil, and colleagues enrolled 54 adults with SLE into an open-label study.

Blood samples were collected immediately prior to intramuscular administration of PPSV23.  Enzyme-linked immunosorbent assays were then performed 4 to 6 weeks later to detect immunoglobulin G (IgG) antibody levels against 7 pneumococcal serotypes.

For the purposes of this study, a positive vaccine response to the PPSV23 was defined as a 4-fold or greater increase in antibody response over baseline levels, or an IgG level ≥1.3 µg/ml in patients whose baseline IgG levels were <1.3 µg/ml.

Of the 54 SLE study participants enrolled, 28 had been taking  cyclophosphamide, azathioprine, or mycophenolate mofetil, in addition to any doses of prednisone, for at least 6 months prior to PPSV23 administration.  The remaining 26 study participants had not received any of these immunosuppressants, and all participants were taking prednisone at doses of less than 5 mg per day.

Positive serotype responses to the PPSV23 ranged from 43.7% to 77.7% among patients receiving immunosuppressants, and from 52.3% to 90% in those who did not receive immunosuppressants. 

When the mean ratio of production of anti-pneumococcal IgG levels were measured pre- and post-vaccination, the researchers found a mean ratio increase of 6.4% vs 4.7% when comparing participants taking immunosuppressants and those who did not (P =.001).

Summary and Clinical Applicability

This study suggests that the PPSV23 vaccine has poor immunogenicity in patients with SLE, as reflected by lower post-vaccination anti-pneumococcal IgG levels. Rheumatologists should take these findings into account when discussing vaccination efficacy with patients.  However, at this point the PPSV23 is not only safe for patients with SLE, but currently recommended. 

“Currently, pneumococcal vaccination is strongly recommended for patients with autoimmune rheumatic diseases,” the researchers stated.

Limitations and Disclosures

This study was limited by absence of expert consensus on defining what exactly an adequate serologic response is. Further, levels of antibody that are protective may differ in various individuals

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Reference

Rezende RP, Ribeiro FM, Albuquerque EM, Gayer CR, Andrade LE, Klumb EM. Immunogenicity of pneumococcal polysaccharide vaccine in adult systemic lupus erythematosus patients undergoing immunosuppressive treatment. Lupus. 2016; Published online before print February 27, 2016, doi: 10.1177/096120331663647.