Detection of Neutralizing Antibodies in Patients Treated With Bevacizumab or Ranibizumab
This study will measure antibody levels in the blood of people with bleeding or swelling in the retina who have or have not been treated with bevacizumab (Avastin[Trademark]or ranibizumab (Lucentis[Trademark]). These drugs have been useful in reducing retinal bleeding and swelling in people with eye diseases that cause these symptoms, but the drugs' effects usually wear off and they have to be given repeatedly. In some patients, the benefits become less and less. It is possible that over time, patients taking these drugs may produce antibodies that act against the drugs, thus neutralizing their effects and preventing them from working properly.
People 18 year of age and older who are participating in a current NEI protocol and meet the following criteria may be eligible for this study:
- Are receiving injections of bevacizumab or ranibizumab for bleeding or swelling in the retina, but the treatment is becoming less effective
- Are receiving injections of bevacizumab or ranibizumab for bleeding or swelling in the retina and the treatment is still effective
- Have bleeding or swelling in the retina, but have never received either bevacizumab or ranibizumab
Participants have blood samples drawn once when they start the study, once in the middle of the study, and once at the end of the study. They are asked permission for study researchers to review the results of their eye examinations at NIH.
|Study Design:||Time Perspective: Prospective|
|Official Title:||Pilot Study for the Detection of Neutralizing Antibodies in Patients Treated With Bevacizumab Avastin or Ranibizumab Lucentis|
|Study Start Date:||January 2008|
|Study Completion Date:||August 2009|
|Primary Completion Date:||August 2009 (Final data collection date for primary outcome measure)|
Over the past two years, the field of ophthalmology has witnessed a dramatic paradigm shift in the treatment of exudative and hemorrhagic diseases affecting the retina. This has been due largely to the introduction of two agents, bevacizumab and ranibizumab, into the clinical setting. These agents are humanized monoclonal antibodies which target vascular endothelial growth factor (VEGF). We have observed that, in some patients, a diminished response to these agents occurs with time. One possible explanation for this is the emergence of neutralizing antibodies in patients who have become refractory to bevacizumab or ranibizumab.
We will recruit patients from the National Eye Institute (NEI) who are currently receiving treatment with bevacizumab or ranibizumab for various exudative or hemorrhagic disease of the retina. We will also recruit patients with recently diagnosed exudative or hemorrhagic disease of the retina who are na ve to these medications and are going to be treated with them.
This will be a prospective, observational study.
The main outcome measure will be the titer of neutralizing antibodies which is measured in patient sera using enzyme-linked immunosorbent assay (ELISA). This will be compared between three groups of patients: 1) 10 patients treated with long term (greater than 1 year) bevacizumab and/or ranibizumab in which decreased drug efficacy has been documented; 2) 10 patients treated with long term (greater than one year) bevacizumab and/or ranibizumab in which decreased drug efficacy has not been documented; and 3) 10 patients who are na ve to treatment with bevacizumab and ranibizumab.
|United States, Maryland|
|National Institutes of Health Clinical Center, 9000 Rockville Pike|
|Bethesda, Maryland, United States, 20892|