Chronic idiopathic urticaria or chronic spontaneous urticaria is a condition characterized by itchy hives, swelling or both that recur without a cause for 6 weeks or longer. Its prevalence is between 0.6-0.8% in the general population. We have discussed extensively chronic urticaria in the past http://allergylosangeles.com/allergy-blog/stepwise-approach-to-chronic-urticaria/ and the treatment for it with Xolair http://allergylosangeles.com/allergy-blog/xolair-treatment-duration/. We will now look and see the response rate to Xolair in patients in a new study published in the February 2016 Journal of Allergy and Clinical Immunology.
Xolair for chronic idiopathic/spontaneous urticaria was given in treatment groups for either 12 or 24 weeks. Xolair for chronic hives is given every 4 weeks. Two treatment dosages were given, either 150mg (1 injection) or 300mg (2 injections). Patients receiving 300 mg of Xolair (omalizumab) had the highest rates of response type. Half of the patients receiving 300 mg achieved a significant response by week 6 or complete response by week 12 or 13. After a single 300-mg omalizumab (Xolair) dose, about half of the patients almost had a complete response. Some patients who did not respond within the first 3 doses ended up responding with doses 4-6. Once responding, recipients showed continuous response throughout the study.
For patients who have chronic hives or chronic idiopathic/spontaneous urticaria, there seems to be 2 unique response patterns, early and late. 300 mg of Xolair seems like the best dosage to induce a complete response or lead to well controlled symptoms in patients with chronic idiopathic/spontaneous urticaria. Most patients require omalizumab (Xolair) beyond a single dose (and some up to 6 doses) to demonstrate well-controlled urticaria or complete elimination of symptoms.
Chronic hives can be very worrisome for patients and often times very difficult to treat. Since Xolair was approved for http://allergylosangeles.com/allergy-blog/fda-approves-xolair-for-chronic-urticaria/ chronic urticaria, allergists have been seeing a great response in patients who do not respond to conventional antihistamines such as Claritin, Allegra, Zyrtec or Benadryl. In this study, it shows that Xolair works best at the 300 mg dose and sometimes it takes up 3 doses (4 weeks apart) before a good response is seen. But many patients do respond very quickly (hives clearing up) and that response is sustained for many weeks on Xolair.