Anaphylaxis1
Anaphylactic reactions were rare in clinical trials. However, post-marketing data following a cumulative search in the safety database retrieved a total of 898 anaphylaxis cases. Based on an estimated exposure of 566,923 patient treatment years, this results in a reporting rate of approximately 0.20%.
Arterial thromboembolic events1
In controlled clinical trials and during interim analyses of an observational study, a numerical imbalance of ATE was observed. The definition of the composite endpoint ATE included stroke, transient ischaemic attack, myocardial infarction, unstable angina, and cardiovascular death (including death from unknown cause). In the final analysis of the observational study, the rate of ATE per 1,000 patient-years was 7.52 (115/15,286 patient-years) for Xolair-treated patients and 5.12 (51/9,963 patient-years) for control patients. In a multivariate analysis controlling for available baseline cardiovascular risk factors, the hazard ratio was 1.32 (95% confidence interval 0.91–1.91). In a separate analysis of pooled clinical trials, which included all randomised double-blind, placebo-controlled clinical trials lasting 8 or more weeks, the rate of ATE per 1,000 patient-years was 2.69 (5/1,856 patient years) for Xolair-treated patients and 2.38 (4/1,680 patient-years) for placebo patients (rate ratio 1.13, 95% confidence interval 0.24–5.71).
Platelets1
In clinical trials few patients had platelet counts below the lower limit of the normal laboratory range. Isolated cases of idiopathic thrombocytopenia, including severe cases, have been reported in the post-marketing setting.
Parasitic infections1
In allergic patients at chronic high risk of helminth infection, a placebo-controlled trial showed a slight numerical increase in infection rate with Xolair that was not statistically significant. The course, severity and response to treatment of infections were unaltered.
Systemic lupus erythematosus1
Clinical trial and post-marketing cases of systemic lupus erythematosus have been reported in patients with moderate-to-severe asthma and CSU. The pathogenesis of SLE is not well understood.
For immune system disorder, please see the ‘Special warnings and precautions for use’ section.