An extension study shows that long-term ranibizumab therapy is safe and well-tolerated.
Dr. Jumper, a private practitioner in San Francisco, is a principal investigator for several trials of ranibizumab. Although the small number of patients in the study limits its statistical power, he said, the rate of thromboembolic events was consistent with that of other studies of ranibizumab.
Enrollment in the extension study included patients who had taken part in the first clinical trials of ranibizumab, dating back to about the year 2000, in which investigators were trying to determine the best-tolerated and most-effective dose. Because the drug demonstrated effectiveness during those early trials, investigators invited the patients to continue in an extension study to gather long-term data, Dr. Jumper said. Mean duration of therapy for the 67 treated patients in the extension study was 3.8 years (range, 0.9 to 5 years).
The primary outcome measurement was the discovery of any major adverse events related to long-term treatment. "None were discovered," Dr. Jumper said. "The ocular adverse events were similar to those that we've seen in the other big ranibizumab trials, and the systemic adverse events were in line with other published information on the drug."
The rate for development of the first arterial thromboembolic event was 4.1% per year, comparable to the rates observed in other studies, he added.
"I counsel my patients that [ranibizumab] therapy is a lifelong treatment; how many injections and at what interval I won't know, but you have to think in terms of this being a treatment you get very long-term," Dr. Jumper said. "However, it doesn't seem that long-term therapy is leading to worse problems than we see in the first 2 years," he said.
Nevertheless, he said that ongoing studies with more participants might reveal more about possible systemic adverse events.