"REVISED: Ranibizumab, Bevacizumab and Pegaptanib All Cause Post-Injection Increases in Intraocular Pressure: Presented at ARVO"
The following DGDispatch, originally published on May 7[th, omitted to mention that Avastin is not approved by the U.S. Food and Drug Administration for the treatment of choroidal neovascularisation secondary to age-related macular degeneration.
We apologise to the product's manufacturer for this omission.
We are committed to providing the most accurate, relevant and balanced information for physicians worldwide and have devoted considerable resources to ensuring this. We deeply regret this error.
By Cameron Johnston
FORT LAUDERDALE, FL -- May 8, 2007 -- Three new products -- ranibizumab (Lucentis), bevacizumab (Avastin) and pegaptanib (Macugen) -- can cause significant spikes in intraocular pressure (IOP) that could make them risky for patients with advanced glaucoma, according to a study presented here at the annual meeting of the Association for Research in Vision and Ophthalmology (ARVO).
The three products have all come on the market in recent years. Lucentis and Macugen have been approved by the United States Food and Drug Administration to treat choroidal neovascularisation secondary to age-related macular degeneration. Although Avastin has not been approved for the treatment of CNV related to AMD, it is nonetheless, widely used in the U.S. and in other countries for this purpose. Each of these products has been shown to slow the progression of the disease, to varying degrees.
Researchers led by Allison Toler, OD, optometrist, East Florida Eye Institute, Stuart, Florida, United States, conducted a study of 57 patients who received a total of 169 injections with the drugs. The patients received a total of 75 injections of Macugen (0.09 mL every six weeks), 69 injections of Avastin (0.05 mL as needed), and 25 injections of Lucentis (0.05 mL every four weeks).
The average age of patients was 78 years. At enrolment, 14 had open angle glaucoma, three had normal tension glaucoma, and five were glaucoma suspect. No glaucoma or risk of glaucoma was reported for 35 patients.
IOP measurements were taken within one minute of the initial injection, and then every 5 to 10 minutes until pressure returned to baseline. Vision was evaluated immediately following the injections.
IOP was increased significantly among all patients following the injections. For those receiving Macugen, IOP increased from 13.1 mm Hg at baseline to 41.6 mm Hg after two minutes. This fell gradually to 33.7 mm Hg at 10 minutes, 24.9 mm Hg at 20 minutes and 22.9 mm Hg after 30 minutes.
Patients receiving Lucentis had an increase from 12.6 mm Hg at baseline to 37.2 mm Hg after two minutes. This too fell gradually to 29.2 mm Hg at 10 minutes, 23.7 mm Hg after 20 minutes and 16.6 after 30 minutes.
Patients receiving Avastin, patients had an increase IOP from 14.1 mm Hg at baseline, to 36.8 mm Hg two minutes after the injection, to 29.2 mm Hg after 10 minutes and 23.7 after 20 minutes. At the 30-minute point, their IOP had returned to a mean of 16.6 mm Hg.
The difference in IOP spikes over baseline was significant in all groups, but was lower with Avastin and Lucentis compared with Macugen, especially in the first 10 minutes. By the 20 minute mark, IOP had decreased more with Lucentis than with either Avastin or Macugen.
While these increases in IOP were transient and resolved in relatively short order, they could be serious for patients who have existing glaucoma, Dr. Toler said in an interview on May 6th.
Two patients who had the most severe glaucoma at enrolment experienced reduced vision as a result of the injections, she said. One of these patients had tried all three drugs and had the greatest increase in IOP when using Lucentis.
No other clinically significant important changes in vision were reported in any other patients in the study. The fact that these increases in IOP were short lived is also important, Dr. Toler said, because other injections such as triamcinolone, which is used in some cases to treat AMD and detached retinas, has been associated with much higher increases that have lasted out to nine months and more.
It could be that the greater increase in IOP that was seen with Macugen was, in part, a result of the larger volume of injections that are required with that agent, she said. However, this would not explain why a difference was seen with Lucentis and Avastin, since the volume of injections were the same, and they are, to a very significant degree, similar molecules.
Dr. Toler said that it is now common practice in the clinic to advise any patients with glaucoma, or those who are suspected of having glaucoma, that this is a high-risk procedure and that they are at greater risk of exacerbating their glaucoma, more so than other patients who have normal or close-to-normal IOP.
The risk of recurrent injections must be carefully weighed against the risk of glaucomatous progression in patients who already have advanced glaucoma, and perhaps, in some cases, the presence of glaucoma should be considered a contraindication to treatment with either of these drugs, Dr. Toler said.
The study, which was not sponsored by the makers of the drugs, was conducted in conjunction with the Bascom Palmer Eye Institute, at the University of Miami School of Medicine.
[Presentation title: Is IOP a Concern Post-Injection of Macugen, Avastin, or Lucentis? Poster 74/B183]
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