
Visual acuity gains seen in the first two years of the CATT study were not maintained at year five, regardless of whether the patient was treated with bevacizumab or ranibizumab, according to Dr. Daniel F. Martin, study chair.
Dr. Martin, who was speaking at the American Society of Retina Specialists annual meeting said, “Between year two and year five, there was a mean 11-letter decrease, such that at five years, the average patient was three letters worse than they were at baseline.”
In the National Eye Institute-funded follow-up study, CATT patients who were alive at the end of the initial two-year clinical trial were invited to return for a follow-up visit that included assessment of visual acuity, a review of records, and imaging studies with colour fundus photographs, fluorescein angiography and SD-OCT. Data were available for 647 patients (71 per cent of those eligible), mean age was 83 years, and follow-up ranged from 4.3 years to 7.1 years.
The population reviewed was elderly and 200 of the initial CATT cohort had died since being enrolled in the study 5.5 years ago.
Between year two and year five, there was a mean 11-letter decrease, such that at five years, the average patient was three letters worse than they were at baseline
Another approximately 200 patients were unable to participate for age-related reasons, such as moving to an assisted living facility. Of those who could participate, 91 per cent (591 patients) were continuing their care at a CATT centre, although only 25 per cent of patients continued treatment exclusively with their CATT-assigned drug, making comparisons between the two drugs irrelevant in this follow-up.
“The thrust of this was no longer a comparison of Lucentis to Avastin, monthly vs. PRN,” Dr. Martin said. “The primary interest here was to assess the global effect of anti-VEGF therapy on five-year outcomes, specifically visual acuity and anatomical results.”