Among patients with lupus, B-cell monitoring can guide treatment with anti-CD-20 agents, according to a recently published study.
“[Treatment] with anti-CD20 agents can be guided by B-cell monitoring with the aim of achieving complete depletion,” Edward M. Vital, MD, from the University of Leeds in the United Kingdom, and colleagues wrote. “About one in eight patients with [systemic lupus erythematosus] SLE lose depletion on repeat cycles of rituximab, regardless of prior response, and secondary non-depletion is associated with anti-rituximab antibodies.”
Researchers assessed 117 patients with SLE who were treated with rituximab for 12 years. Patients with a secondary non-depletion non-response (2NDNR) were treated with either ocrelizumab or ofatumumab.
After the first cycle, 82% of patients achieved a British Isle lupus assessment group response, as 32% achieved a partial response and 50% achieved a major response. Investigators found an increased chance for major response among patients who were younger (odds ratio [OR] = 0.97) and patients who had B-cell depletion after 6 weeks (OR = 3.22).
Of the 77 patients treated on clinical relapse, 85% responded in the second cycle. Of the second cycle non-responders, nine met criteria for 2NDNR and also tested positive for anti-rituximab antibodies. Five of these patients switched to ocrelizumab or ofatumumab and all depleted or responded.
“If 2NDNR occurs, switching to humanized anti-CD20 mAbs restores depletion and response,” the researchers wrote. “Therefore, alternative anti-CD20 antibodies may be more consistently effective in SLE treatment and several ongoing trials are addressing these issues.” – by Will A. Offit
Disclosures: Vital reports he is a National Institute for Health Research (NIHR) Clinical Scientist and has received honoraria and research grant support from Roche, GSK and AstraZeneca.