A clinical trial has been reported to show that the low cost drug Avastin is as effective as the costly FDA approved Lucentis when it comes to treating age related macular degeneration (AMD). The results from the first year of a two year study have confirmed a belief long held by ophthalmologists, many of whom have used Avastin, off label, to treat the debilitating eye disease.
Both Avastin and Lucentis were developed by Genentech, Avastin to prevent blood vessel growth that enables cancerous tumors to develop and spread. As the manufacturer of both drugs, Genentech, had no incentive to sponsor a comparison trial. Indeed, the company has been accused of trying to sow doubts about the efficacy and safety of bevacizumab for AMD.
The report, from the Comparison of AMD Treatments Trials (CATT), was published online in the New England Journal of Medicine. Dr. David M. Brown, retinal surgeon at The Methodist Hospital, oversaw the study, part of a multi-centered, single-blind, randomised clinical trial sponsored by the National Eye Institute (NEI), part of the NIH.
The results of the CATT study show at one year, bevacizumab (Avastin) and ranibizumab (Lucentis) had equivalent effects on visual acuity when administered according to the same schedule.
The results of the CATT study show at one year, bevacizumab (Avastin) and ranibizumab (Lucentis) had equivalent effects on visual acuity…
“This important study validates the use of off-label Avastin for wet AMD which will provide significant cost savings to many patients. The second year of the CATT study will be particularly important to assess whether the anatomic superiority of Lucentis seen in the first year will make any difference on long-term visual outcomes,” said Dr. Brown.
NEI launched CATT in 2008 to compare Lucentis and Avastin for treatment of wet AMD. The study has now reported results for 1,185 patients treated at 43 clinical centers in the United States. Patients were randomly assigned and treated with one of four regimens for a year. They received Lucentis monthly or PRN, or Avastin monthly or PRN.
Enrolment criteria required that study participants had active disease. Patients in the monthly dosing groups received an initial treatment and then had an injection every 28 days. Patients in the PRN groups received an initial treatment and were then examined every 28 days to determine medical need for additional treatment. PRN groups received subsequent treatment when there were signs of disease activity, such as fluid in the retina.
Change in visual acuity served as the primary outcome measure. Thus far, visual acuity improvement was virtually identical (within one letter difference on an eye chart) for either drug when given monthly. Also, when each drug was given on a PRN schedule, there was no difference (within one letter) between drugs. PRN dosing required four to five fewer injections per year than monthly treatment and resulted in slightly less sustained vision gains.
Dr. Brown and his team of clinician-researchers were instrumental in contributing to the U.S. Food and Drug Administration’s 2006 approval of Lucentis for the treatment of patients with wet AMD.
AMD is a major cause of central visual loss and is one of the leading causes of blindness in people over 60. The NEI estimates that there are 1.7 million people with the advanced form of AMD in the United States and that this prevalence will grow to 2.95 million by 2020.
