CATT Study Update 7: An Interesting Commentary by Dr. James Folk
Posted Sep 26 2008 5:17pm
Dr. James Folk, in his Med Rounds blog, has just published this update on his previous writings about the CATT Study. His basic premise is that regardless of which drug turns out to be better in treating wet AMD, either Avastin or Lucentis, Genentech wins.
I expect that the first results from the CATT Study will be published this fall at the upcoming American Academy of Ophthalmology (AAO) meeting. If so, I will present them in this space.
I’ve written before about the Comparisons of AMD Treatments Trials (CATT). Recruitment of wet AMD patients is well underway into a study that compares four groups:
1. Monthly Lucentis® injections.
2. Monthly Avastin® injections.
3. One Lucentis injection followed by monthly visits and additional injections only as needed.
4. One Avastin injection followed by monthly visits and additional injections only as needed.
Genentech, which makes both drugs, has stated that Lucentis is the proven drug for AMD and should be used instead of Avastin. Retinal surgeons however, have generally found that both drugs are effective. Retinal surgeons are switching from Lucentis to Avastin. I think around 80% of the retinal experts in this country are now using Avastin in lieu of Lucentis. They feel that Avastin works just as well, is cheaper, and lasts longer in the eye resulting in less frequent injections.
Genentech was not supportive of the Lucentis versus Avastin trial especially since they were selling billions of dollars worth of Lucentis. But now, with the sales of Lucentis flat or even falling, the results of this trial could benefit them. I personally believe that there will not be much of a difference between the two drugs. But if the trial shows that the visual results are better with Lucentis, retinal surgeons will be hard pressed to recommend Avastin to their patients.
But the biggest boon to sales may be in the comparison of groups 3&4 above to groups 1&2. Most retinal surgeons now follow a protocol similar to groups 3&4. If the retina is dry, they may decide not to reinject. Many doctors may still reinject but then increase the number of weeks until the next visit. When you think about it, we’re often waiting for a relapse of swelling before doing another injection. There is a greater likelihood that groups 3&4 won’t do as well as group 1&2 than there is a chance that one drug is better than the other. If this is the case, Genentech still wins, because now injections will be given more often, perhaps even once a month. More injections equal more drug sold.
We have complained about the high price of Lucentis but both of these drugs have saved vision in countless patients with wet AMD.