Long‐term effects of omalizumab on peripheral blood cells and C‐reactive protein levels in patients with chronic spontaneous urticaria

Abstract

Omalizumab's mechanism of action is not well‐understood yet despite its strong therapeutic efficacy in chronic spontaneous urticaria (CSU). To determine the overall effect of omalizumab on peripheral blood cell counts and serum C‐reactive protein levels (sCRP) during a 1‐year follow‐up in patients with CSU. Data of 74 patients (male/female: 20/54) were reviewed from medical charts. Leucocyte counts, percentages of peripheral blood cells(lymphocyte, monocyte, neutrophil [PPBN], eosinophil, basophil [PPBB]) and sCRP were recorded at baseline, 3rd, 6th, 12th months of omalizumab treatment. Although a dramatic increase in the mean PPBB (±SD) was observed at the 3rd month, PPBB (%) gradually decreased after the 3rd month (PPBB: 0.38 ± 0.21 [baseline] vs. 0.59 ± 0.3 [3rd month], p = .002). However, 12th month PPBB remained higher than baseline (PPBB:0.38 ± 0.21 [baseline] vs. 0.46 ± 0.27 [12th month], p = .03). A dramatic decrease in the mean PPBN (%) was noticed within the first 3 months (PPBN:62.85 ± 8.97 [baseline] vs. 58.37 ± 9.07 [3rd month], p = .04), and 12th month PPBN remained lower than baseline values (PPBN: 62.85 ± 8.97 [baseline] vs. 60.31 ± 8.02 [12th month], p = .045).Mean sCRP (mg/dL) decreased rapidly within the first 3 months (sCRP: 1.09 ± 1.53 [baseline] vs. 0.56 ± 0.45 [3rd month], p = .17) and 12th month sCRP still remained lower than baseline levels (sCRP: 1.09 ± 1.53 [baseline] vs. 0.83 ± 1.06 [12th month], p = .01). Omalizumab substantially increases PPBB,and reduces PPBN accompanied by a reduction in sCRP especially in the first 3 months; however, these effects may continue in the long‐term. The alterations in peripheral blood cell ratios and sCRP may contribute to the therapeutic effect of omalizumab in CSU.

Genome-Wide DNA Methylation Profile in Whole Blood of Patients With Chronic Spontaneous Urticaria

“…In this study, leukocyte composition analysis showed the proportions of CD8 + T lymphocytes decreased in the CSU patients. Our results are consistent with those of a previous study (30,31). In our study, the percentage of granulocytes was significantly higher in the blood samples of the CSU patients than that in the blood samples of the healthy controls.…”

The Pathogenesis of Chronic Spontaneous Urticaria: The Role of Infiltrating Cells

“…165 A study of 74 patients with CSU receiving omalizumab 300 mg every 4 weeks for at least 1 year resulted in a substantially increased peripheral blood basophil count and reduced peripheral blood neutrophil especially in the first 3 months. 166 The authors proposed that the alterations in peripheral blood cell ratios might contribute to or reflect the therapeutic effect of omalizumab in CSU. In another retrospective study of 74 patients with CSU receiving omalizumab 300 mg every 4 weeks, the neutrophil count, the neutrophil/lymphocyte ratio, and the neutrophil/monocyte ratio showed a statistically significant reduction after 12 weeks of omalizumab treatment.…”

Role of Basophils in a Broad Spectrum of Disorders

“…Omalizumab, a humanized monoclonal anti-IgE antibody, has been approved for the treatment of CSU (86,87). Notably, the omalizumab therapy rapidly increases the blood basophil number (88)(89)(90), whereas the number of FceRI + cells in skin lesions is decreased by omalizumab treatment (88). These results indicate the possibility that blood basopenia mirrors the recruitment of basophils to the skin lesion.…”