Monday, January 14, 2013

FAHF-2 Clinical Trial Summary

As promised, here's the update on the last round of clinical food challenges. I've seen both sunrise and sunset today, but I want to do it while it's all fresh in my mind.

I generally do not like to give specific details about my son's situation, but I know a lot of you are invested in the stats so in this case, I'll make an exception.

1.71 (class 2)
3.5 mm
~3.0 mm?
(not sure about this one)
No reaction
Peanut consumed
496 mg
~9 peanuts
1746 mg (almost 6 peanuts)

Please keep in mind this is just one kid, and there's no guarantee the other kids will have patterns at all like this. However, it's interesting that a) the RAST number went up pretty significantly, and b) the amount of peanut tolerated after 3 months off the medication went down slightly.

I'm going to do the rest of this in a Q&A format, since I basically spent the whole morning asking questions of the clinical trial manager and on-call physician. Again, keep in mind these are only their opinions. Actual mileage may vary.

Q. Will the tolerance we saw with peanut extend to his other allergens?

A. No reason to think it will not. The formula has been used in Eastern medicine for all allergens. (We will work with our own physician to pursue new RAST testing and challenges if appropriate.)

Q. Once the trial ends and the medication is available again to trial participants, is there a recommendation for how it should be taken? 

A. This is an open question at this point. However, in Chinese medicine, the tradition has been for people to take the medicine for nine months and then take three months off. This was probably because two of the ingredients in the original FAHF formulation had some liver toxicity associated with them. Those two ingredients were dropped from the second (FAHF-2) formulation for that reason. As a result, the thought is that patients may need to stay on the medication life-long.

On the other hand, the tolerance may last. No one really knows.

Q. What route will be taken for commercialization? What's the timeline?

A. Right now, it does look like the researchers are pursuing an FDA approval (vs. going to market with a "dietary supplement"). This will ensure the widest availability. However, it also takes a little longer.

Q. So what happens next?

A. The medication has been reformulated in a more concentrated form. That form will need to be tested for efficacy in Phase 3 clinical trials just starting in Dallas. (Heads up, Texas residents!) Participants will take 10 pills a day, 5 in the morning and 5 at night. This should significantly reduce the issues with compliance. (One of the issues they had with the Phase 2 trial was the difficulty for kids of getting in three doses, with food, without dosing as school since that's difficult for many schools to manage.) If the current trial shows positive results and the Phase 3 trial also succeeds, the researchers will pursue commercialization. That's probably still a couple years away.

Q. So was the trial successful?

A. Obviously this is what we'd all like to know! However, even if she could have shared it with me (which she can't at this point), our clinical manager indicated that she really doesn't know. 1 in 3 kids in the trial were receiving placebo, so it's impossible to tell the difference between a child who didn't respond to the medication and one who didn't receive the medication.

Q. What does success even look like?

A. There are two separate outcomes that will need to be evaluated to determine whether the trial was successful. First, did children show an increase in threshold? My son's experience was a definite yes: depending on which food challenge you look at, he showed an increase between 3X and 5X in the amount of peanut he could consume before a reaction occurred.

The second measure of success is severity of reaction. This one is trickier to measure because, while this trial attempted to use objective symptoms before calling a food challenge, subjective symptoms were used if they were persistent. There's obviously some anxiety for these kids going into a food challenge, so they are going to be more aware of all their bodily sensations. Since the amount of peanut is often tied to severity of reaction, it will be hard to evaluate whether the reactions were milder because of the medication, or whether the kids just got anxious and bailed.

Important to note: this is more my interpretation of what may have happened, not the researchers' opinion. Unfortunately, the researchers could not share specifics about the other kids at this point, other than to say there was a range of response with regard to both threshold and reaction severity.

Q. Was the change in RAST what they expected?

A. Well...sort of. Our trial manager said my son's RAST probably went up due to the known peanut exposures, even though tolerance increased. I was under the impression that they expected RAST to go up, then come back down, so it will be interesting to see what happens with the rest of the kids in the trial.

Q. When will the information from the trial be made available?

A. Probably end of summer, 2013. The last participant is finishing the main part of the trial in June.

Q. Is there any thought that kids should be taking a daily dose of peanut to help maintain tolerance?

A. No. That's outside the scope of this trial, there's no continuing supervision to make that happen, and there's no guarantee at all of how long any increased tolerance will last. (The tolerance was achieved without any peanut consumption at all, so maintaining it would have more to do with the medication than with actually eating peanut.)

Q. What changes can the kids in the study make to their diet, now that the study has completed?

A. Really, none. In our particular case, the researchers were pretty secure telling my son that cross-contamination was not a real concern. However, I clarified today that that's primarily because his starting threshold was already so high. All the kids in the study are definitely not being told this. In general, the advice is to continue to strictly avoid peanut and always carry epinephrine. (In addition, they reiterated that reactions are unpredictable -- the mild ones we experienced as part of the study are no guarantee of future mild reactions.)

Q. Is there any thought that my son's milder reactions/slow response time perhaps are because he's really allergic to pea and just cross-reacting to peanut?

A. According to the researchers, very unlikely. A peanut allergy seems to be most often be what it appears to be: a true peanut allergy. Different people just respond differently.

Q. Are we still "just five years away from a cure"?

A. This is a little inside joke among my food-allergy friends. I've been told "just 5 years" for almost 18 years now.

However...our clinical trial manager's opinion on this is that one of the trials they're working on will definitely pan out into a usable treatment. The hard part for me to hear was that she's not necessarily betting on FAHF-2. She spoke with a great deal of enthusiasm about both the oral immunotherapy (OIT) with omalizumab (Xolair) and the peanut patch trial currently underway. However, that may just be because those trials are the new kids on the block. We'll see when the data is correlated from all the reporting sites whether FAHF-2 is a go.

I think that was everything I thought of to ask. If you do have a specific question I didn't answer here, post it in the comments. It's possible I've already asked it and just didn't note it here -- if that's the case, I'll add it in.

Also, if you're just finding my blog, here are the other posts specifically about FAHF-2 in order:

FAHF-2 Trials In Chicago!

We're In

BTDT, Got the FAHF-2 Food Allergy Clinical Trial T-Shirt

Brief FAHF-2 Update

Halfway There...But the Second Half Is All Uphill

FAHF-2: The Holy Grail?

Waiting in the Wings for the Show to Begin

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