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FDA Approves Subcutaneous Version of Rituximab

medfeb

Senior Member
Messages
491
I can imagine the FDA would require a demonstration that a subcatenous dosing regimen - which would likely result in different blood levels of drug and other changes in drug pharmacokinetics - is still effective and safe in RA. I don't know what mechanisms they require to demonstrate that other than indication specific studies.
 

Gingergrrl

Senior Member
Messages
16,171
Rituximab has a fairly high percentage of causing allergic and infusion reactions but with an infusion you can stop it immediately, push plain saline and IV Benadryl etc, and usually quickly turn it around. I would be terrified to do it in an injection form b/c once it is injected, if you are allergic, it is too late. I also have doubts that an injection would be as effective but I could be wrong.
 

Jonathan Edwards

"Gibberish"
Messages
5,256
Rituximab has a fairly high percentage of causing allergic and infusion reactions but with an infusion you can stop it immediately, push plain saline and IV Benadryl etc, and usually quickly turn it around. I would be terrified to do it in an injection form b/c once it is injected, if you are allergic, it is too late. I also have doubts that an injection would be as effective but I could be wrong.

Exactly my thoughts, Gingergrrl. Why bother with sub-cut. If you are going to have a potentially toxic medicine once a year (which is probably all you need for RA for many people) why not have it comfortably IV in a clinic with somebody looking on? Sub cut is a license for cowboys to my mind.
 

Gingergrrl

Senior Member
Messages
16,171
Exactly my thoughts, Gingergrrl. Why bother with sub-cut. If you are going to have a potentially toxic medicine once a year (which is probably all you need for RA for many people) why not have it comfortably IV in a clinic with somebody looking on? Sub cut is a license for cowboys to my mind.

I agree with you 100% and my first infusion is in two days. It will be done at the infusion center where I have done a full year of IVIG and they know every detail of my case and with every possible precaution in place. It will take 8-10 hours but this is comforting to me vs. an injection would scare the hell out of me (and I actually would not do it).
 

flitza

Senior Member
Messages
145
Rituximab has a fairly high percentage of causing allergic and infusion reactions but with an infusion you can stop it immediately, push plain saline and IV Benadryl etc, and usually quickly turn it around. I would be terrified to do it in an injection form b/c once it is injected, if you are allergic, it is too late. I also have doubts that an injection would be as effective but I could be wrong.

I think I read that because of the risk of infusion reactions, and because they occur most frequently with the first dose that it may be a requirement to give the first dose IV before doing the subsequent doses sub-q.

I'll try to find where I read that tomorrow...
 

Gingergrrl

Senior Member
Messages
16,171
I think I read that because of the risk of infusion reactions, and because they occur most frequently with the first dose that it may be a requirement to give the first dose IV before doing the subsequent doses sub-q.

That makes sense or a lot of people could die of anaphylaxis! There is no scenario that I would do the injection form but am glad to hear they are at least taking this precaution.

It seems even stranger for cancer patients since the infusion is supposed to be very slow to avoid tumor lysis syndrome (which does not pertain to me but the allergic reaction does :eek:).
 

flitza

Senior Member
Messages
145
Rituximab has a fairly high percentage of causing allergic and infusion reactions but with an infusion you can stop it immediately, push plain saline and IV Benadryl etc, and usually quickly turn it around. I would be terrified to do it in an injection form b/c once it is injected, if you are allergic, it is too late. I also have doubts that an injection would be as effective but I could be wrong.
Found this: https://www.gene.com/media/press-releases/14670/2017-06-22/fda-approves-rituxan-hycela-rituximab-an

It suggests one advantage (of sub-q) being the rapidity of administration. Other advantages are that the personnel don't have to be as highly trained to do sub-q, and the risks of intravascular administration, vessel damage, air bolus, extravasation are avoided as well.
 

Gingergrrl

Senior Member
Messages
16,171
It suggests one advantage (of sub-q) being the rapidity of administration. Other advantages are that the personnel don't have to be as highly trained to do sub-q, and the risks of intravascular administration, vessel damage, air bolus, extravasation are avoided as well.

It's interesting but for me the rapidity of the injection would be a disadvantage and I would love to have been able to do Ritux in a hospital with a super slow 24-hour infusion (instead of outpatient with an 8-hr infusion) but we couldn't get that approved. There are certain risks that come with IV's in general which would be avoided with an injection but am not sure those are unique to Ritux and after a year of IVIG, I am not too worried about them and luckily still have enough good veins left.