Is Cytoxan (still) the gold standard?

[csjknits]

Thank you, this post helps me to understand a bit better. I have a basic idea of T-cells but don't know much about B-cells. Now I have more to read!

My doctor is not in favor of RTX but I'm not certain if it's an overall feeling (like you mention above, the idea of the mavericks) or a sense that in my specific case it's not the best option. I am only now in the midst of my first round of treatment, and the plan as I understand it is that he would like me to stay on cytoxan a year after I achieve remission. I am gathering all of the articles I can find (I work at a university so I have really good access) and am trying to understand what the literature says regarding best practice/evidence-based practice. I don't want to stay on cytoxan if I don't have to.
It seems that the discussion is really in the risk-benefit category. I'm less likely to flare if I stay on Cytoxan, but I have to deal with the long term effects of ctx. Flares may be more common on other maintenance drugs, but the risks from the drugs are lower. Oh the choices!

[annekat]

Me, too, on the lifetime quota of CTX, I think. I use MTX for maintenance and have knocked down mild to moderate flares by increasing the dose of it and the pred. But for a big flare, I'd probably need RTX. I'm curious, though, Marta and Pete, does using RTX for maintenance somehow make it less effective in the case of a big flare? And does that question even make sense, since it should theoretically prevent the flare in the first place? I don't know to what extent its dosage, or frequency of infusions, might then be increased in the case of a big flare, or if there's any reason that wouldn't work... but then, I know nothing, and realize they don't yet have all the answers.

In any case, though I wish I'd gotten less CTX, it did work, and the MTX is working, and I'm happy, so far, to not have to face the possibility of RTX at this time. Saving it for the big one seems like a good plan to me.

[Pete]

Me, too, on the lifetime quota of CTX, I think. I use MTX for maintenance and have knocked down mild to moderate flares by increasing the dose of it and the pred. But for a big flare, I'd probably need RTX. I'm curious, though, Marta and Pete, does using RTX for maintenance somehow make it less effective in the case of a big flare? And does that question even make sense, since it should theoretically prevent the flare in the first place? I don't know to what extent its dosage, or frequency of infusions, might then be increased in the case of a big flare, or if there's any reason that wouldn't work... but then, I know nothing, and realize they don't yet have all the answers.

In any case, though I wish I'd gotten less CTX, it did work, and the MTX is working, and I'm happy, so far, to not have to face the possibility of RTX at this time. Saving it for the big one seems like a good plan to me.

I dunno. I hope there's an effective "big gun" when I need one.

[annekat]

I dunno. I hope there's an effective "big gun" when I need one.

Well, you were just on RTX for a short time, right, when your kidneys started to show involvement, and it worked, right? So if you have a big flare at some point, I would think RTX would again be the appropriate "big gun". Of course, I hope that never happens, but if it does, maybe by that time they will know a lot more and maybe there'll even be a better "big gun"!

I'm just a bit confused about this business of "saving" RTX for a big flare, for those of us who shouldn't take more CTX, and not understanding why using it for maintenance in the meantime would rule out using it for the big flare. If that's what's being implied. Just being analytical... it's not that I have any desire to use it when other things are working fine. I'd rather avoid all the hassle and whatever expense I'd incur in getting the infusions, unless they are the only option at some point. The pills we take may not be perfect or the most pleasant, but they sure are a lot easier to get ahold of and use.

[Pete]

I'm just a bit confused about this business of "saving" RTX for a big flare, for those of us who shouldn't take more CTX, and not understanding why using it for maintenance in the meantime would rule out using it for the big flare. If that's what's being implied. Just being analytical... it's not that I have any desire to use it when other things are working fine. I'd rather avoid all the hassle and whatever expense I'd incur in getting the infusions, unless they are the only option at some point. The pills we take may not be perfect or the most pleasant, but they sure are a lot easier to get ahold of and use.

I'm reading between the lines a bit here, but in my conversations with Dr Villa Forte, I think there is some research behind the "big gun" theory.

[annekat]

I'm reading between the lines a bit here, but in my conversations with Dr Villa Forte, I think there is some research behind the "big gun" theory.

So it sounds sort of like saving it until it's really needed makes it more of a "big gun", somehow. Maybe Marta will have some insights, too. I'm certainly content to wait. Good to know it is there, as it may well be the best and only option at some point.

[drz]

My doctors are on the same page for the reasons outlined below. RTX is my plan for a serious flare but otherwise it is AZA for maintenance till they find a cure for Wegs or better treatment alternative.

Here's my take on the whole thing. It's from personal experience, articles I've read (a long time ago, when all of this was 'top of mind') and other's experiences.

There are two proven 'heavy hitters' we have in our arsenal to beat down a flare: CTX and RTX.

CTX is chemotherapy, which is designed to kill off T-cells, and B-cells, but also kills off any fast reproducing cells (including hair ). When metabolized in the body one of it's by-products is a known carcinogen that can cause bladder cancer if not continually flushed through with water. I was attached to my water bottle like a security blanket. I was on CTX for a year. In most studies the max should be 6 months.

RTX is a biologic, designed to target only B-cells. So it's basically B-cell ablation. Once they're ablated, they take between 6-8 months to start repopulating, but now you have the immune system of a newborn. So equally important to stay away from any infectious situations.

Some docs use RTX as a maintenance drug once remission is achieved, but my doc doesn't believe this to be prudent (and keep in mind it's a drug that's less than 10 years old, so everyone's a Maverick) as it's the only option I now have to beat down a flare. It's our Ace in the pocket. So we use Imuran (AZA) for maintenance, knowing that if the poo hits the fan again, I have RTX to take care of the problem. CTX is completely out of the question for me now... I've had my life's quota, and then some.

I hope my ramblings make some sense and help a little.

[MikeG-2012]

and the plan as I understand it is that he would like me to stay on cytoxan a year after I achieve remission.

From what I gathered from all the sessions at the Symposium last week, a year on Cytoxin is NOT the standard any more--six months tops! The preferred big gun for this disease is Rituxan.

I would really recommend having your doc consult with one of the leading wegs specialists. I know if I were asked to go back on cytoxin again, I'd definitely get a second opinion. That long of a dose can wreak havoc on your body and predispose you to bladder cancer.

[csjknits]

Glad to have news to post to this thread. I'm now about four months post hospitalization for GPA. I hesitate to say first "attack" because I suspect I've had them before but didn't know that's what was happening. My creatinine is down to 1.2 and my gfr is 55, just about normal again on both counts. I feel pretty good. I'm down to 10 mg pred daily and will keep decreasing.
I've changed doctors and now the person I've put in charge of my care is my nephrologist. I was not comfortable with the rheumatologist's plan for cytoxan long term, nor was I enjoying the rapid taper of prednisone (to say the least).
My new plan is to stay on the cytoxan for about another month, just to make sure things stabilize, and then to try Imuran, with Rtx as the next step if Imuran does not work.
In the meantime, I have dosing questions regarding cytoxan. Is there published info anywhere about what dosing should be, or a general sense of how much people take? I know it's based on body weight. I'm on 250mg a day and that seems like a lot.... I'm a little overweight but not much. this is the same dose I've been on for four months.

[annekat]

Sounds like you have a good handle on things and I agree with your switching docs away from one who'd have you on long term CTX. I still feel, though, that CTX is a valuable drug that may be the best initial choice in some cases, as long as time on it is limited. As for dosage per weight, that seems a little harder to find on the web than when I was dx'ed in 2011, but what I have found is 2mg per kg per day. 100 lbs is about 45kg, so a person of that weight would take 90mg/CTX/day according to that formula. And a 200lb person would take 180mg., and so on. These would likely be rounded up to 100 and 200, respectively, especially considering that a person would likely be a few pounds over those weights. In my case, the weight formula said I should take 125mg., but the doc had me on 100mg most of the time. I did get better on that slightly reduced amount. But he had me on it too long, as I may have said above... around a year, with a reduction to 50mg/day toward the end as he transitioned me to MTX and overlapped the two for awhile. Though there are things about my treatment I disagree with in retrospect, I have done well and am presently in good shape, though still on meds. I hope this helps with the dosage question.