EyeWorld Asia-Pacific December 2014 Issue

51 EWAP PHARMACEUTICALS December 2014 be relatively safe. “In the CATT study there were signals that bevacizumab had a higher incidence of adverse events,” Dr. Boyer said. This may be a spurious finding, he said. “At this moment in time, I think that everyone would say they’re all pretty safe,” Dr. Boyer said. “The only caveat now is that Avastin has to go to a compounding pharmacy to be made up and that adds one additional step where there could be contamination, and there have been a few outbreaks of endophthalmitis.” Dr. Warren concurs that the compounding pharmacy issue may be problematic. “The FDA and CMS recently gave advice regarding compounding pharmacies,” he said. “The current recommendation is that patients have to get an individual prescription.” Use of the anti-VEGFs does not necessarily only fall to retinal specialists. Dr. Boyer finds that a variety of practitioners are administering the anti-VEGF drugs, depending on where their practices are located. Patients in rural areas are less apt to travel to see a specialist, he explained. However, the drugs administered may differ, with comprehensive ophthalmologists tending to offer the less costly Avastin, Dr. Boyer noted. “Rarely do I see them using the higher priced drugs because you have to have a lot of money tied up in inventory.” Patient compliance For any of the anti-VEGFs to be effective, patients must be willing to return to the office on a regular basis. Dr. Boyer finds that compliance with these injections varies depending on the condition being treated. “The macular degeneration patients are very compliant once they get an improvement in vision,” he said. “If they don’t get an improvement in vision, they start to question whether it’s worthwhile getting these injections.” Meanwhile, the diabetic patients tend to have a more difficult time returning to the office because they have to take time off work, he said. “It’s much more difficult to keep them on a monthly or 6-week treatment schedule.” Dr. Natarajan finds that the majority of patients at his center do return for treatment regularly. “We have a counselor explain to them the need and the benefit,” he said. The hospital has worked on educating patients here, giving Amsler charts to everyone. “We have created the first hanging Amsler grid garden in the world in our hospital,” he said. This helps to draw attention to the importance of retinal health. Going forward, Dr. Natarajan believes that either longer-acting agents or alternative ways of administering the anti-VEGF medication are needed. “I think we need a drug that will be long- lasting or [one] where the dosage is released periodically,” he said. While it sounds like science fiction, this could potentially be done with nanotechnology, where a laser is used to release more of the drug each month. EWAP Editors’ note: Dr. Boyer has financial interests with Genentech and Regeneron. Drs. Natarajan and Warren have no related financial interests. Contact information Boyer: vitdoc@aol.com Natarajan: prof.drsn@adityajyoteyehospital.org Warren: kwarren@warrenretina.com Views from Asia-Paci c Kenneth C.S. FONG, MD Consultant Ophthalmologist and Vitreoretinal Surgeon Sunway Medical Centre Jalan Lagoon Selatan, 47500 Petaling Jaya, Malaysia Tel. no. +603-74916585 kcsfong@gmail.com Web: eyeretina.my A nti-VEGF therapy has been a revolution in the treatment of a variety of macular diseases including wet AMD, diabetic macular edema, macular edema due to retinal vein occlusion, and myopic choroidal neovascularization. The three main agents in use currently are bevacizumab (Avastin), ranibizumab (Lucentis), and a ibercept (Eylea). Due to cost constraints in most Asian countries, Avastin remains the most widely used anti-VEGF agent despite the fact that it is not licensed for intravitreal use. All three agents are highly effective and most head-to-head trials comparing agents suggest that they are equally good at improving vision. The duration of action is longer with Eylea and this allows a greater interval between injections of up to 2 months whereas Avastin and Lucentis require monthly injections. There are three key issues facing ophthalmologists who wish to use anti-VEGF agents: 1. Safety of Avastin compounding 2. Correct diagnosis of the macular disease 3. Follow-up regimen after initiation of treatment While Avastin is cost-effective as an anti-VEGF agent, there are concerns about its safety due to the need for compounding of the drug into multiple doses from a single vial. This may lead to outbreaks of endophthalmitis and subsequent loss of vision. There have been several high pro le clusters of endophthalmitis reported throughout the world related to Avastin use. This potential risk needs to be explained to the patient. One of the ideal ways to compound Avastin has been described by Gonzalez et al. 1 I would not recommend drawing out the drug multiple times from a vial of Avastin kept in a refrigerator for a period of time as there are many potential routes of contamination. We also have to be aware of the existence of counterfeit Avastin vials in circulation and this was suspected to be the cause of an endophthalmitis outbreak in China. 2 For any ophthalmologist who wishes to start treating patients with anti-VEGF agents, they must have access to an OCT scanner. The macular OCT is indispensable when managing a patient with macular disease. Ophthalmologists must be pro cient in interpreting OCT scans to distinguish cases like epiretinal membrane that will not respond to anti-VEGF treatment. For cases that are not responding to anti-VEGF treatment, further investigations like uorescein and indocyanine angiography may be required and a referral to your local retinal service would be of bene t. Finally, it has to be emphasized that anti-VEGF therapy is not a cure and multiple injections are required to improve and stabilize vision. It can be frustrating for both patient and ophthalmologist as the total number of injections required for a particular condition is not known. I often start with a loading dose of three monthly injections of any of the anti-VEGF agents and then monitor the macula with monthly OCT scans to look for signs of recurrence (PRN approach) and then treat if required. The main drawback is that the patient does not know if they need an injection when they come for their follow-up visit. Another approach is called “treat and extend” where the patients are brought back at longer intervals, e.g. every 6 to 8 weeks and injected at each visit. The ideal treatment regimen is yet to be determined so patients need to be counseled that they need at least six injections a year, on average, and regular follow-up checks are essential. References 1. Gonzalez S, Rosenfelt PJ, Stewart MW, et al. Avastin doesn’t blind people, people blind people. Am J Ophthalmol . 2012;153:196-203. 2. Wang F, Yu S, Liu K, et al. Acute Intraocular In ammation Caused by Endotoxin after Intravitreal Injection of Counterfeit Bevacizumab in Shanghai, China. Ophthalmology . 2013;120:355-361. Editors’ note: Dr. Fong is a consultant for Allergan (Irvine, Calif., U.S.), Bausch + Lomb (Rochester, NY, U.S.), Bayer, Novartis, and Quantel Medical.