Tendon rupture is a potential issue also for NA and surgery. The critical number is how often it happens and that obviously depends on the skill of the doctor. Though Auxilium talks about "educating the surgeon base" my feeling is that Xiaflex will not only be applied by surgeons but also by other MDs. Training them how to avoid side effects like tendon rupture makes a lot of sense to me.
The article cites 0.14 % tendons ruptures per shot. As fingers might need more than one shot it might be in the 0.15 - 0.20 % range per finger. The according percentage for NA is about 0.01 % (http://www.dupuytren-online.info/NA_side_effects.html). Surgery reports e.g. 0.2 % tendon damage (more frequent than rupture, i.e. actual rupture would be less!) (http://www.dupuytren-online.info/surgery...s_denkler_2.htm). The statistics for Xiaflex is certainly not very good, 3 ruptures doesn't make good statistics, so we need to wait until more patients have been treated. My concern would be that the numbers of CORD and JOINT studies are certainly from trained personell. It might be worse with less or not trained doctors.
In the article at the tiny url there is this statement
"Kaplan also described nerve injury as surprisingly low and added that no one reported temporary numbness."
I was in the III stage clinical study and reported numbness in my finger. It was temporary and it was minor (lasting about six weeks) - but I did have numbness - so Kaplan is incorrect in his statement.
By comparison, how many of us *have* been told about Xiaflex, even though it is not yet available, and the latest reports indicate that Phase III trials show that Xiaflex is probably not as safe as NA? My guess would be that CHS speak far more about it than NA.
Being averse to all thing medical. the fact that Xiaflex generally requires a minimum of two interventions vs. just one for NA is EXTREMELY off-putting. For me (and presumably others), Xiaflex would have to have some other major comparative advantage vis-a-vis NA to justify its use in lieu of NA . e.g. more effective, reduced risk of complication, lower recurrence rate, less expensive, less pain/discomfort, faster recovery, etc. From what I have gleaned thus far, Xiaflex offers none of these advantages.
It's a " tested product" being marketed to hand surgeons, rather than a controversial new technique they'd have to go somewhere to learn - at their own expense. Insurance companies may like it for this reason too.
I recently had NA at Mayo - quite an expensive procedure at a total of $3K, of which insurance only paid half because Mayo isn't in my provider network. If - next time - I could accomplish the same thing closer to home, with Xiaflex injections by an in-network surgeon, I'd save $1500.
The talk about losing a finger was total unfounded speculation, and from what I understand, a misleading exaggeration of what could happen even in a worst case. If Xiaflex was that destructive to all tissue, it seems like simply injecting it anywhere in the hand would be a disaster. I think it was not good journalism to include that comment. I'd also point out that Xiaflex is in trials for frozen shoulder, and if that finger loss was remotely possible, we'll be hearing of entire arms falling off. Somehow, I don't think that is going to happen.
The tendon rupture issue is more real. My sense is that to some degree, that happened simply because the procedure is utterly new. It would be useful to have the details of how they happened, and the expertise of the person doing the injections, and the injectionists narrative of what happened. Without that knowledge, it is very hard to reasonably assess and extrapolate about the future.
I also get a strong sense of conflicted interests in the reporting, especially from hand surgeons. It is, rather predictably, not surprising that some are busy building arguments aimed at limiting the use of Xiaflex to their specialty. If I were a surgeon doing a lot of old-fashioned fasciectomies, you can bet I would be interested in keeping as much of the business to myself as possible after the introduction of a new treatment.