So, I realize the vast majority of my readers don’t want to hear about my personal health issues – y’all can skip this post. But, to be honest, I’ve spent much of January in doctor’s offices or hospitals and many of the topics I’ve been following most closely are medical ones. And now I find myself very interested in a bit of a medical controversy, a controversy involving a drug I’m hoping to have injected in my eye in about a month.
I’ve been a type 1 (juvenile onset) diabetic for 21 years. I monitor my diabetes very closely and am in “tight control” (hgbA1c = 5.3, for you diabetes geeks out there). But, like a lot of diabetics, I’ve been having problems with diabetic retinopathy. For those unacquainted with this charming disease, it’s the result of the degredation of very small blood vessels in the retina of the eye. Excess sugar in the blood causes the vessels to swell and degrade. Parts of the retina get insufficient oxygen, so the body responds by trying to grow new vessels on the retina. Unfortunately, these new vessels are fragile and malformed – they have a very high chance of breaking and causing bleeding within the eye, which can cause vision loss or blindness. Diabetic retinopathy is the leading cause of blindness in adults.
Once this sort of retinopathy – proliferative diabetic retinopathy – starts its course, the major weapon you’ve got to preserve your eyesight is “photocoagulation”. This procedure involves shining a green laser through your pupil to cause burns on the retina. These burns kill off the new blood vessels – the opthamologist doesn’t target the center of the retina, just the periphery, which means it damages your peripheral vision, though not the central vision.
I’ve had eight photocoagulation treatments done over the past year, with another scheduled for tomorrow morning. They suck. Everything you read about the procedure suggests that it might be “uncomfortable” – believe me, when the laser hits a branch of the optic nerve, it’s more than uncomfortable. I’ve learned to prepare for treatments with a large dose of aspirin and a shot of whiskey before I get into the operating room… I actually have formal medical instructions telling me to drink a shot of rye half an hour before the treatment.
Photocoagulation kills off the blood vessels, but it doesn’t stop them from regrowing. In most diabetics, you fry a few thousand holes in the retina and tell the patient to get their blood glucose under control in the hopes that vessel growth will slow. But my glucose is about as good as it’s going to get, and we’re starting to look for other options. One (really bad) option is vitrectomy, the surgical removal of the vitreous humor that fills the inside of your eye. While the surgeon is scooping goop out of tiny incisions in your eye, she scrapes the new vessels from the retina. This is very effective – very few people experience new proliferation of blood vessels afterwards – but it’s major surgery, and something I’d very much like to avoid.
Doctors have been wondering if there’s a way to turn off blood vessel regrowth in retinopathy patients. They’re focused on blocking the effects of a protein called VEGF (vascular endothelial growth factor) which promotes blood vessel growth. There’s a bunch of drugs that block VEGF – most of them need to be injected into the eye, close to the retina, to be effective. Two of the most effective drugs are made by Genentech – Avastin, which was developed as an anti-cancer drug, and Lucentis, which was developed specifically for use in the eye.
The drugs work through similar mechanisms and are chemically similar, though the drug in Lucentis is a smaller molecule. Genentech believes this means that Lucentis will bond more tightly to VEGF (a good thing, as that’s what we’re trying to block) and will leave the system faster than Avastin (a good thing, as it lessens chances of side effects.)
But there’s a major reason that people want to use Avastin instead of Lucentis – it costs $50 a dose, as compared to Lucentis, which is priced at $1950 a dose. And eye doctors believe it’s as effective as Lucentis, possibly more effective.
What you’d really like to do in this case is a side by side study of Avastin versus Lucentis to see whether there’s really a measurable difference in efficacy and safety between the drugs. But Genentech has made it clear they’ve got no interest in running that study. Why should they? They’ve spent millions of dollars developing a drug specifically for retinopathy and macular degeneration – sure, it’s expensive, but it’s far cheaper than fitting your computer out with a braille reader, or getting another half dozen sessions of photocoagulation.
Most of the patients who would be receiving Lucentis are elderly. Many of those patients are on Medicare, which means the $2,000 per shot is financed by the US taxpayer. This is likely one of the factors that inspired the National Institutes of Health to run a side-by-side study of the drugs, estimated to cost $16 million over the course of four years. The cost difference per year for American taxpayers, if Avastin were available for this use, is estimated at $5 billion.
NIH says that they’re not performing the study for cost reasons – their reason for the study is that an uncontrolled study is already taking place, with opthamologists purchasing Avastin and using it in an off-label use instead of Lucentis. (This off-label treatment is something I’m currently scheduled for late next month.)
Genentech is evidently pretty pissed that a US government agency is running a drug trial instead of allowing them to choose whether or not to test a drug for a particular use. Irv Arons, who writes about opthamology issues on his blog, quotes a report from an American Academy of Opthamology meeting:
Industry entities (pharmaceutical and device companies in general â€“ not just Genentech) reportedly are attempting to prevent the newly announced head-to-head trial sponsored by the National Eye Institute (NEI) of Genentechâ€™s Lucentis and Avastin in AMD. Dr. William Rich, an American Academy of Ophthalmology legislative expert, said, â€œWe are very concerned about an intervention of industry into getting this trial carried outâ€¦We are monitoring it very carefullyâ€¦We do anticipate some interference with the start of this trial by industryâ€¦Industry is going to petition not to see this trial carried outâ€¦I wouldnâ€™t be surprised (to see the trial stopped). And public interest groups (e.g., AARP) around the country are going to be watching carefully, too.â€
I’ll be watching, too. I understand and respect the need for pharma companies to recover their research costs. I understand that having Avastin approved for this use would likely cost Genentech billions of dollars and would likely tank their stock price. (My opthamologist has advised me to short Genentech based on this controversy…) But given the cost differential and the fact that many opthamologists are already using Avastin, it seems pretty churlish to try to block this study.
Even if I’m able to scrape up several thousand dollars a year to afford monthly Lucentis injections (my HMO is unlikely to cover the full cost of the drug – Medicare covers less than a third of the cost of Lucentis), diabetes is a global disease that’s growing quickly. Doctors in middle income nations aren’t going to be able to persuade their patients to use a drug that costs over $10,000 a year. They’re going to use Avastin, for a few hundred dollars a year. Which means that it would be a really, really good idea to do a systemic study on the use of the drug to make sure that it doesn’t cause brain warts or the unexplained dissapearance of fingers and toes somewhere further down the line.
I trust the doctors who’ve been treating me. They haven’t even put Lucentis on the table as an option, possibly because they’re sufficiently antagonized by Genentech’s behavior. If they think Avastin is safe enough to inject it into my eye, I’m willing to give it a shot. Here’s hoping the National Institutes of Health will be able to tell me if I made a bad mistake in about four years.