Avastin
A number of ophthalmologists who specialize in retinal disease have been writing and asking about Avastin® (bevacizumab), which was covered in the Sept 19th blog. A number of retinal specialists have begun using Avastin® for the treatment of patients with the wet or neovascular form AMD. Most of these patients are those who have not responded well to treatment with Visudyne® or Macugen®. The early results reported at The Retina Society meeting and from a polling of my colleagues, indicate that Avastin® usually controls the abnormal blood vessels in AMD and can result in increased vision. We still don’t know if there are any long-term side-effects from intraocular Avastin®. Most of us believe however that this treatment should be safe because the risks were low with the long-term use of Lucentis®, which is a smaller fragment made from Avastin®. In addition some patients need only two or three injections of Avastin® (at monthly intervals) to control the neovascularization which is probably safer than the multiple injections used with Lucentis® or Macugen®.
A good discussion for both patients and physicians about the possible risks and benefits of this drug can be found on http://www.omic.com/. Click on the informed consent tab on the right and then scroll down to Avastin®.
The remaining part of this blog is directed to retinal specialists and is therefore rather technical. It still may be of interest to the layperson especially if they have AMD.
To the retina doctors: the dose is 1.25mg per 0.05ml given intraocularly, like Macugen®. A reputable and approved pharmacy should prepare doses from a large bottle of Avastin® under sterile conditions and then keep them at 4◦ centigrade. We ask our pharmacy to place about 0.2cc in a 1mm (TB) syringe. We then order it from the pharmacy when we need it for a patient, let it thaw, place a 30 gauge needle on the end of the syringe, expel the extra along with any bubbles until we get to 0.05 ml, and then inject it through the pars plana like Macugen®. The small volume delivered into the eye through the sharp fine needle is usually well tolerated even with topical anesthesia but a small bleb of subconjunctival anesthetic can also be used.
Our pharmacy charges us around $125 per dose, which is reasonable. I wouldn’t worry as much about the price as I would about the quality of the pharmacy preparing the doses. Medicare should pay for the drug and the injection. Some docs worry about the off-label use of Avastin™ but I don’t think this is a big issue if you are using it in the best interests of your patient. Remember we use Kenalog®, intravitreal antibiotics, and tissue plasminogen activator in an off-label manner also. There are several articles in PubMed that discuss this use of Avastin® [Pubmed Search Results].
This field is evolving rapidly but here is what I currently do (most of the time): I start with the FDA approved treatments that have been proven in large trials, namely Visudyne® or Macugen™. I usually recommend Visudyne® immediately followed with 4mg of Kenalog® intravitreally to a patient who has a small to medium size CNV that has a classic component (does not necessarily have to be over 50% classic because I also use Kenalog®). I usually recommend Macugen® to a patient who has a large CNV, a medium or large occult CNV, an indiscrete CNV, or a CNV associated with blood. I use either Visudyne® with Kenalog® or Macugen® for a patient with a symptomatic small occult CNV.
At the first three-month visit after the Visudyne® plus Kenalog® treatment or after 2-3 Macugen® injections, I re-evaluate with fluorescein angiography and optic coherence tomography. If the fluid is mostly gone and the CNV is about the same size, I continue the same treatment. If the CNV is larger or there still is subretinal fluid, I’ll usually recommend Avastin®. The patient’s opinion as to whether the sight and distortion is improving or not can also be very helpful in making your decision as to which treatment to use. In general, I have not had good luck with switching from Visudyne® to Macugen® or from Macugen® to Visudyne®. The clinical conundrum we all face is to wait long enough to see if the treatment is working but not wait too long until it is too late to try something else. This seems a reasonable compromise to me at this time. If we find that Avastin® is as good as we hope it is, we may switch treatments sooner.
Good luck and please write with any opinions or questions. Jim
A good discussion for both patients and physicians about the possible risks and benefits of this drug can be found on http://www.omic.com/. Click on the informed consent tab on the right and then scroll down to Avastin®.
The remaining part of this blog is directed to retinal specialists and is therefore rather technical. It still may be of interest to the layperson especially if they have AMD.
To the retina doctors: the dose is 1.25mg per 0.05ml given intraocularly, like Macugen®. A reputable and approved pharmacy should prepare doses from a large bottle of Avastin® under sterile conditions and then keep them at 4◦ centigrade. We ask our pharmacy to place about 0.2cc in a 1mm (TB) syringe. We then order it from the pharmacy when we need it for a patient, let it thaw, place a 30 gauge needle on the end of the syringe, expel the extra along with any bubbles until we get to 0.05 ml, and then inject it through the pars plana like Macugen®. The small volume delivered into the eye through the sharp fine needle is usually well tolerated even with topical anesthesia but a small bleb of subconjunctival anesthetic can also be used.
Our pharmacy charges us around $125 per dose, which is reasonable. I wouldn’t worry as much about the price as I would about the quality of the pharmacy preparing the doses. Medicare should pay for the drug and the injection. Some docs worry about the off-label use of Avastin™ but I don’t think this is a big issue if you are using it in the best interests of your patient. Remember we use Kenalog®, intravitreal antibiotics, and tissue plasminogen activator in an off-label manner also. There are several articles in PubMed that discuss this use of Avastin® [Pubmed Search Results].
This field is evolving rapidly but here is what I currently do (most of the time): I start with the FDA approved treatments that have been proven in large trials, namely Visudyne® or Macugen™. I usually recommend Visudyne® immediately followed with 4mg of Kenalog® intravitreally to a patient who has a small to medium size CNV that has a classic component (does not necessarily have to be over 50% classic because I also use Kenalog®). I usually recommend Macugen® to a patient who has a large CNV, a medium or large occult CNV, an indiscrete CNV, or a CNV associated with blood. I use either Visudyne® with Kenalog® or Macugen® for a patient with a symptomatic small occult CNV.
At the first three-month visit after the Visudyne® plus Kenalog® treatment or after 2-3 Macugen® injections, I re-evaluate with fluorescein angiography and optic coherence tomography. If the fluid is mostly gone and the CNV is about the same size, I continue the same treatment. If the CNV is larger or there still is subretinal fluid, I’ll usually recommend Avastin®. The patient’s opinion as to whether the sight and distortion is improving or not can also be very helpful in making your decision as to which treatment to use. In general, I have not had good luck with switching from Visudyne® to Macugen® or from Macugen® to Visudyne®. The clinical conundrum we all face is to wait long enough to see if the treatment is working but not wait too long until it is too late to try something else. This seems a reasonable compromise to me at this time. If we find that Avastin® is as good as we hope it is, we may switch treatments sooner.
Good luck and please write with any opinions or questions. Jim
More blogs on Avastin:
posted by James C. Folk, M.D. at 2:19 PM
3 Comments:
The field of medicine is exciting in all the new prospects being researched to help people preserve vision.
In the meantime, there are a number of steps people can take proactively to help maintain healthy vision.
Research is proving that macular degeneration can be very responsive to nutritional supplementation. A large research study from Harvard showed that even supplementing with 6 mg of lutein per day could reduce your likelihood of getting macular degeneration by 57% (Seddon, J.M., U.A. Ajani, et al. (1994). “Dietary carotenoid, vitamins A, C, E, and advanced age-related macular degeneration. Eye Disease Case-Control Study Group Jama 272(18):1413-20). That same study showed that the specific carotenoids, lutein and zeaxanthin, which are primarily obtained from dark green leafy vegetables, were most strongly associated with a reduced risk for AMD. Individuals consuming the highest levels of carotenoids had a statistically significant 43% lower risk for AMD. The AREDS study showed that supplementing with a combination of betacarotene, vitamins C and E, zinc and copper could significantly reduce the chances of dry macular degeneration turning to wet macular degeneration.
So there certainly are preventative measures you can take. Additional beneficial nutrients include omega-3 fatty acids, taurine, vitamins A and E, selenium, zinc copper, beta-carotene, gingko biloba.
For those with macular degeneration, research has shown that this is a condition that can be very responsive to specific nutritional supplementation (lutein, zeaxanthin, taurine, omega-3 fatty acids, vitamins A and E, selenium, beta-cartoene, zinc and copper to name a few), diet and lifestyle. Also, microcurrent stimulation done daily at home along with specific supplementation can be very effective in helping protect against vision loss. The last research study done by a Dr. Ed Paul showed that 73% of the people who did microcurrent stimulation daily along with specific supplementation showed improved vision up to 2-3 lines on the eye chart. As a result of this study, there are now 4 double blind FDA approved studies starting (including one at New York Eye & Ear Infirmiary) studying the benefits of the microcurrent stimulation for macular degeneration along with some other retinal dystrophies. For more information and related research studies, you can go to http://www.naturaleyecare.com/diseases.asp?d_num=8 -- you can also read the specific research studies on microcurrent stimulation and macular degeneration at http://www.naturaleyecare.com/store/detail.aspx?ID=1545
For questions and answers, you can also go to our blog on natural eye care at http://www.bulletinboards.com/message.cfm?comcode=nec2
Because Avastin has yet to be approved for treatment of Macular Degeneration, Medicare will not pay for it.
Avastin® has been FDA approved for the treatment of metastatic colon cancer. Physicians have the right to use an approved drug for any disease however, if they believe it will benefit their patient. For instance we inject drugs such as Kenalog®, antibiotics, and tissue plasminogen activator into the eye to treat various retinal diseases. None of these drugs was originally approved to treat ocular disease. In fact, intravitreal antibiotics are now the standard of care for treating endophthalmitis, and a physician could be sued if he/she didn’t use them in this non-approved fashion.
Medicare has recognized this and generally pays for both the drug and the injection. This is the case in Iowa where Medicare has been reimbursing us for both the Avastin® and the injection. It’s smart for them to do that because Visudyne® and Macugen® are more expensive than Avastin®.
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