Clinical course and side effects of anti-IgE monoclonal antibody in patients with severe persistent asthma

Omalizumab, a recombinant humanized monoclonal antibody to IgE, is recommended as a new option for the treatment of severe persistent allergic asthma. The purpose of this study is to assess the effects omalizumab treatment on life quality and its side effects in severe persistent asthma patients.

In this study, we evaluated 19 severe persistent asthma patients who received therapy with omalizumab for 8 months. Omalizumab was administered every 2 weeks at doses between 150 to 375 mg. Symptoms and severity of allergic reactions were recorded before and after being on omalizumab. IgE levels, mean platelet volume (MPV), platelet levels, pulmonary function test, and asthma control test were evaluated in all patients before and 8 months after the treatment. Local and systemic side effects of omalizumab were evaluated. Stool parasites were examined in the 4th and 8th month after initiation of treatment to investigate any parasitosis.

The patients had severe persistent asthma for periods ranging from 3 to 8 years, and they were diagnosed with allergic asthma for 7 - 28 years. Thrombocytopenia developed in a male patient after the 22nd dose of the drug was given. When the platelet count fell down to 55000, the omalizumab treatment was suspended. During the therapy period, one patient had parasitosis (giardiasis), one patient had severe side effects, one patient had dyspnea two hours after the injection, and one patient had a dyspnea attack 2 hours after the injection. The changes in MPV levels were not statistically significant. There was also a significant decrease in IgE levels after the treatment.

Monitoring of complete blood cell count is very important when using this drug. Though we did not see anaphylaxis in any patients, we believe that the patients should be monitored at least for 3 hours after the omalizumab injection.