[Lisa V]

Hi Bill,

Ken has had 2 ATGs, both of them horse. The reasoning was that it worked the first time for him (he relapsed during the cyclo taper) so why switch? Better to hold the rabbit in reserve in case the horse doesn't work.

Refresh my memory, did you have a response the first time? If not, then a switch may be in order. Most doctors don't seem to want to backtrack from rabbit to horse, though. From what I've read, rabbit is considered both stronger and easier to tolerate (although judging from some patient responses this may be debatable). Whatever the reasons, the usual order seems to be horse, then rabbit, and then there are others (skunk, goat) if those don't work out, but we rarely hear of them.

I'm not sure what the daily dosage was, but our doctor consulted with someone in the midwest (not sure who, it may even have been Maciejewski?) who recommended a longer series of infusions with each successive ATG. The first time around he got it for 5 days, so the second time they gave it to him for 10 days. Presumably if he had to do it again they'd want to give him 15 days. The good news is he had a quicker and stronger response the second time around, so that seems to have been the right call for him.

Cyclosporine dosage is another matter. It's usually calculated based on body weight, but may require quite a bit of tinkering based on cyclo and creatinine readings in the blood. Ken's has had to be decreased significantly from what he started out at (900 mg/day) due to kidney issues. He's now at a maintenance level of 175 mg/day, which seems to be working out for him. His situation is a bit different than most people's because his Trisomy 8 clone suggests he may never be able to taper without relapse, but really, everybody's situation is unique. There is no one-size-fits-all protocol. You start with the standard and then adapt it to fit your needs.

Hope this helps,