Safety of off-label biologicals in systemic lupus erythematosus

The approval of belimumab and other advances in the field have narrowed the window for off-label use of biologicals in systemic lupus erythematosus (SLE). For consideration in severe and refractory disease, safety will play a major role.

We reviewed the literature on safety aspects of off-label biological use in SLE. Significant evidence is available for rituximab, whereas data on the off-label SLE therapy with other biologicals are much more limited. Published trials and open-label experience in SLE allow for some conclusions on abatacept, and on approaches targeting TNF, IL-1 and IL-6 receptors.

Anti-TNF antibodies apparently are the only ones inducing SLE-specific autoantibodies, but even these were not associated with flares. Risks for severe infections certainly remain a major serious concern, particularly in combinations with glucocorticoids and/or immunosuppressants. These findings reiterate that experience with both the disease and the drugs will be essential for keeping patients safe. The available data suggest a manageable adverse event profile for rituximab and do not prove unacceptable risks for other biologicals. Reports frequently only include very few patients, with the inherent danger of bias due to lacking reports on failed treatment attempts.