Peptides and Re-Tests / Trials

[CureOrBust]

I was wondering, Opexa have made major improvements on the efficacy of Tovaxin by increasing the number of "Peptides" used, to identify MRTC's. In each case, they did not appear to be required to go back to Phase I trials.

Does this mean, that after it has gone through Phase III, they will be able to improve the process by increasing the number of Peptides without needing to go through the 3 phases of trial a process again?

[havingms]

I am assuming that since they didn't have to redo any of the phase Ia or IIa trials as they increased the peptides that wont be an issue in the future.
Tim might be able to answer your question.

[dignan]

Cure, just a guess, but since the new formulation of Rebif had to do phase 3s, I think Tovaxin would too if they changed the drug in any way, especially a way that would be purported to alter its efficacy.

[IHaveMS-com]

Hi Cure,

Does this mean, that after it has gone through Phase III, they will be able to improve the process by increasing the number of Peptides without needing to go through the 3 phases of trial a process again?

I would agree. They would not need to do further trails at any stage. I went from a 6-peptide vaccine to the current 109-peptide vaccine. I assume the increased number of peptides was reported to the FDA, but no phase of my trial was extended or repeated.

Adding to the group of peptides does not effect how Tovaxin works. It just enables Opexa to tease out more MRTCs. The purpose of Tovaxin is to selectively eliminate the MRTCs.

[dignan]

I think the FDA's answer would be based on this:

FDA Link

If somebody wants to take a crack at deciphering the legislation, I'd love to hear an answer. I get the impression that the FDA has to consider every drug change on a case by case basis, but what do I know?

[IHaveMS-com]

Hi Dignan,

(c)(1) A change in the manufacturing site or a change in the manufacturing process, including a change in product formulation or dosage strength, beyond the variations provided for in the approved application.

I cannot debate what I do not have information about, but the 114 patients that Dr. Zhang treated at Baylor in the late 1990s, were treated without being part of an FDA study. That was because Tovaxin is autologous, and the T-cell vaccine is a process not a drug. By 2000, the FDA had decided that the process had to go through FDA approval, and thus began my study.

Opexa currently has 163 peptides from the myelin proteins MOG, PLP, and MBP. 109 of the peptides have been found to stimulate myelin reactivity in WBCs of patients with MS. Patients have produced as many as 19 different MRTCs. Opexa is aware that there may be more useful peptides, and I assume provided for that possibility in "the variations provided for in the approved application".

[Lyon]

Thanks Tim, I was snooping from the sidelines and this last explanation made things a little clearer for me also.

We had discussed this topic a few months ago and although I'm comfortable with the situation, I didn't completely understand how the changes along the way haven't necessitated Tovaxin going back to phase I.

Seems like they might have been wise enough to cover all the bases ahead of time.

Bob

[IHaveMS-com]

Hi Bob,

Seems like they might have been wise enough to cover all the bases ahead of time.

Time will tell, but I feel confident that new peptides won't send them back for re-approval.

Masking is suppression, not Klingon cloaking.

[Lyon]

Masking is suppression, not Klingon cloaking.

Hi Tim,
Are we going to learn more about masking at some point in the near future?
Bob

[IHaveMS-com]

Hi Bob,

Are we going to learn more about masking at some point in the near future?

This is a true statement if you remove the word near. I have run out of steam for the moment. I will have my Great American Novel completed at least 6 weeks before the first person finishes the IIb trial, mid-September.

[CureOrBust]

I thought I would post my alteria-motive.
Sheba's medical centre T-Cell vaccine is in phase III (while Tovaxin is Phase III). However, it hasn't been showing the results of Tovaxin. It seems obvious they will be first to market, and if they can improve their results without going through the trials again, it could prove very enticing.

[NHE]

Sheba's medical centre T-Cell vaccine is in phase III (while Tovaxin is Phase III).

Tovaxin is actually in Phast IIb if I remember correctly.

NHE

[Lyon]

Tovaxin is actually in Phast IIb if I remember correctly.

You're right NHE, Sheba's in phase III http://tinyurl.com/2rjrwf and Tovaxin is in IIb with plans for a III if all goes well.

CureOrBust, it's a tough call which (Tovaxin or Sheba) would be available in Australia first. The next few years are going to be interesting for people with MS, depending on the order in which some of these treatments become available because prior use of one might preclude you from using another later.

This really is a good time for people with MS to do active monitoring of the things in trial because it might arise that an educated decision will sometimes involve waiting in expectation of something better to become available.

Bob

[CureOrBust]

Tovaxin is actually in Phase IIb if I remember correctly.

As Lyon noted you are correct, my concern is that no matter if its in Phase II OR Phase IIB, it still has to start and go through a Phase III period, which will delay its coming to market, as compared to something already at that stage.

[Lyon]

This is a true statement if you remove the word near. I have run out of steam for the moment. I will have my Great American Novel completed at least 6 weeks before the first person finishes the IIb trial, mid-September.

Thanks Tim, I hadn't noticed your response earlier. I wait with baited breath, or does my wife say that my breath smells like bait??

No matter, I'll be waiting and I'll be the guy with bad breath.

Bob