Treatment with belimumab in systemic lupus erythematosus does not impair antibody response to 13-valent pneumococcal conjugate vaccine.

Background/purpose: The objective of this study was to explore the impact of systemic lupus
erythematosus and belimumab given in addition to standard of care therapy on 13-valent
conjugated pneumococcal vaccine (PCV13) response. Methods: Forty-seven systemic lupus
erythematosus patients and 21 healthy controls were immunized with a single dose of
13-valent conjugated pneumococcal vaccine. Forty systemic lupus erythematosus patients
were treated with traditional disease-modifying anti rheumatic drugs, 11 of those received
belimumab in addition, and 32 patients were treated with concomitant prednisolone.
Quantification of serotype specific IgG levels to 12 pneumococcal capsular polysaccharides
was performed in serum taken before and four to six weeks after vaccination using multiplex
fluorescent microsphere immunoassay. IgG levels against serotypes 23F and 6B were also
analyzed using standard enzyme-linked immunosorbent assays. Opsonophagocytic
assay was performed on serotype 23F to evaluate the functionality of the antibodies. Preand
post-vaccination log transformed antibody levels were compared to determine the
impact of systemic lupus erythematosus diagnosis and different treatments on antibody
response. Results: Systemic lupus erythematosus patients as a group showed lower postvaccination
antibody levels and lower fold increase of antibody levels after vaccination
compared to controls (p¼0.02 and p¼0.009, respectively). Systemic lupus erythematosus
patients treated with belimumab in addition to standard of care therapy or with only hydroxychloroquine
did not differ compared to controls, whereas the other treatment groups had
significantly lower fold increase of post-vaccination antibody levels. Higher age was associated
with lower post-vaccination antibody levels among systemic lupus erythematosus
patients. Conclusion: Belimumab given in addition to traditional disease-modifying
anti rheumatic drugs or prednisolone did not further impair antibody response to 13-valent
conjugated pneumococcal vaccine.