Time-course and dose-effect of omalizumab in treating chronic idiopathic urticaria/chronic spontaneous urticaria

Several studies have shown that subcutaneous injections of omalizumab can treat chronic idiopathic/spontaneous urticaria (CIU/CSU) patients by only assessing the efficacy on specific endpoints. This study aimed to quantitatively analyze different doses of omalizumab in CIU/CSU and compare it with ligelizumab.

Literature searches were performed in PubMed, Embase, and Web of Science databases. A model-based meta-analysis (MBMA) was utilized to develop a model incorporating time since the initiation of treatment and dose for omalizumab, with the change from baseline in Urticaria Activity Score (CFB-UAS7) as the primary efficacy endpoint. The time-course and dose-effect relationship throughout the omalizumab treatment period was analyzed, and the findings were compared with those of the investigational ligelizumab.

The model equation for the CFB-UAS7 was established as E = –E_max × time/(ET₅₀ + time) × (b₀ + b₁ × dose). The estimated values of the model parameters \({E}_{\mathrm{max}}\) $E_{\max }$ , \({ET}_{50}\) ${\mathit{ET}}_{50}$ , \({b}_{0}\) $b_0$ , and \({b}_{1}\) $b_1$ were −1.16, 1.26 weeks, −9.90, and −0.0361 mg⁻¹, respectively. At week 12 after the first dose, the model-predicted CFB-UAS7 for 150 mg and 300 mg of omalizumab were −16.0 (95% CI, −17.2 to −14.8) and −21.7 (95% CI, −22.9 to −20.5), respectively. In the PEARL-1 trial, the CFB-UAS7 for 72 mg and 120 mg of ligelizumab were −19.4 (95% CI, −20.7 to −18.1) and −19.3 (95% CI, −20.6 to −18.0), respectively. In the PEARL-2 trial, these values were −19.2 (95% CI, −20.5 to −17.9) and −20.3 (95% CI, −21.6 to −19.0), respectively.

Omalizumab showed a significant dose-dependent effect in the treatment of CSU. Both 72 mg and 120 mg ligelizumab might have the potential to outperform 150 mg (but not 300 mg) omalizumab.