I had not viewed the video and not much was in the summary - so I want back and listened to the section on SS-31 peptides and though it was interesting and more helpful than just the summary in this area.
Matt obviously knows quite a bit about the SS-31 peptides, given that his mentor was someone who worked closely with Hazel on the early research on SS-31 in mice many years ago. Matt brings up good points… there is no indication that SS-31 will have any impact on lifespan. He does admit that if the mouse studies translate to humans, we could expect some benefits in bio-energetics (muscle energy) and frailty reduction. He then balances that agains the risks of grey market peptides. And it’s true we don’t know the long term effects in humans (but thats going to be the case with most newer peptides or drugs given the relatively short phase three clinical studies).
The counter is that there actually have been quite a few human clinical trials with SS-31 with no side effects seen other than the injection site pain. The key issue in the equation (for me) is the safety/purity issue of the SS-31 peptide you’re using. If it’s well tested and quality verified, then the risk is only in the peptide itself (not the contaminants, etc. that could be in the peptide). And given the results seen so far, I would still be interested in trying it.
Here is the full transcript of the section where Matt discusses the SS-31 peptide. I think its worth a read, for anyone interested in this peptide:
SS peptides I’m going to put in the “avoid” category unless you have mitochondrial disease. I don’t think there’s any evidence in healthy people. And by the way, that’s not a supplement. That’s a prescription medication. So that’s the one that I was saying doesn’t really fit into the supplement category.
I know a lot of people are excited about peptides in general. A lot of people are excited about SS peptides. I say avoid. And I feel pretty strong on the avoid here. Again, not because I know anything dangerous about SS peptides, but I think there’s a few reasons not to go out and start taking SS peptides from a purely risk-reward perspective, unless you have some sort of mitochondrial disorder, and then that’s a different conversation.
So, just to make sure everybody really understands what we’re talking about here, SS peptides are in fact not a supplement. They are sort of a prescription medication, and they land in this gray area where doctors can prescribe them. As we’ll talk about, the SS peptide most people are going to be taking is SS-31 (or Elamipretide) that was just recently granted accelerated FDA approval. So a doctor can now prescribe SS-31, but it falls in this gray area of the peptides where some people are getting them from compounding, some people are getting research grade off the internet. It’s just kind of ugly and messy right now.
So what do we know about SS peptides from a data perspective? They’ve been around for 20-plus years. SS-31 in particular. I actually was around a lot of the early SS peptide work at the University of Washington because Hazel Szeto, one of the “S’s” in SS, collaborated extensively with my mentor, Peter Rabinovitch, on SS-31 work looking at mitochondrial function in mice. Peter, by the way, is one of the greatest people who I’ve ever had the opportunity to work with. As I said, he was a mentor of mine, and I’m just super grateful for all of the support he gave me throughout the years. Also a fantastic scientist.
And they did a lot of work in mice, treating mice with SS-31 and looking at: where does it go? How does it work? What are the effects on health span and lifespan? And so I think what we’ve learned through Peter’s studies and lots of other studies that Hazel did is SS-31 indeed localizes to mitochondria. It can interact with cardiolipin at least in some contexts. It can reduce mitochondrial fragmentation, reduce reactive oxygen species production, and increase ATP production or energy production. But the idea that SS-31 or any of the SS peptides are general “mitochondrial boosters” supporting mitochondrial function is just sort of a massive oversimplification of the biology. It’s very context dependent.
And my recollection of the mouse data that Peter’s lab and others did was that SS peptides can sort of remodel the mitochondrial proteome, improve some aspects of mitochondrial energetics, potentially improve muscle function in aging mice, but didn’t increase lifespan. So again, it’s one of these situations where maybe a few health span metrics are improved, but it doesn’t seem to be, at least in those experiments, a general longevity drug or general geroprotector. Having said that, if it had similar effects in people without any side effects, that might be something to consider. Maybe it would be beneficial for frailty in people as they’re aging.
So what do we actually know though about SS peptides in people? So, as I mentioned, Elamipretide was recently approved by the FDA—that’s SS-31—for Barth syndrome. But it wasn’t a sort of full approval. It was this accelerated approval path. And that’s because Barth syndrome is a rare childhood mitochondrial disorder where there really aren’t any other treatments available. So, it got this accelerated approval based on the fact that it’s for a severe disease without any alternative treatments, and there was a reasonable expectation that it might work.
So what hasn’t been shown is that SS-31 actually has efficacy for Barth syndrome or for anything else, at least not in the context of an FDA approval process. So we don’t know—it’s gotten this accelerated approval. We don’t know whether it actually works for this indication or for any indication for that matter. There are some other ongoing studies in humans and I think we just have to kind of wait and see. And I know a lot of people are frustrated with the FDA clinical trial process. It takes too long. I get all that. And you really want to know what the safety profile looks like and whether there’s a reasonable expectation that this is going to work for what you want to use it for.
Nonetheless, a lot of so-called “self-proclaimed longevity doctors” have started prescribing SS-31 for use in their patients. And you know, I’m sure they’re starting to get case reports, information about whether SS-31 has benefits, what the side effects look like, but it’s really hard to know what’s real and what’s not real at this point.
So, for that reason, I’d say the reward part is pretty questionable. Like maybe modest benefits for mitochondrial function. There was one study that I’m aware of in healthy older people where there were some indications of improved mitochondrial bioenergetics. That’s kind of what we know I think for healthy older people in SS-31 at this point. So that’s the potential reward. Maybe modest impact on mitochondrial function, maybe best case scenario, modest protection against frailty maybe, but not a lot of indications this is going to be a big effect size intervention. Certainly not compared to something like exercise.
And then what is the risk? Again, we really don’t know because we don’t have, as far as I know, any long-term studies in people. And there’s a few reasons to think that there could be some risks. First of all, we don’t really know the dosing for what we’re trying to use it for. Again, not a lot of data in people, and most of that comes from mitochondrial disease. So, we don’t know the dose. We know we are putting a foreign peptide into mitochondria. And so anybody who understands mitochondrial biology will recognize that there are some reasons to think you want to be careful about putting something into mitochondria that isn’t normally there. Doesn’t mean it’s going to have detrimental effects. Doesn’t mean it’s going to cause problems, but often it is the case when you put foreign proteins or peptides into the mitochondria, it creates a stress response that can be net detrimental. So we want to be a little bit careful about that.
And then I think outside of the SS peptide itself, and this is true for a lot of the peptides that are out there in general, there’s real reasons to be careful about purity and contamination in the peptide preps themselves. For reasons that somewhat due to lack of regulation, somewhat due to opportunism by people of questionable ethics, you might say there’s a lot of people selling peptides of uncertain purity. And so if you get it from a compounding pharmacy, that’s better than buying it from a random person on the internet who’s selling research grade peptides. But even peptides from compounding pharmacies have been sometimes found to have impurities that can lead to problems like allergic reactions.
So, I think you just want to be real careful when you think about the risk-reward with peptides in general, especially peptides that are not FDA approved, especially peptides that are research grade, and with peptides that we don’t have a ton of data, especially human data like SS-31 to understand what the safety profile looks like. I feel pretty good about putting SS-31 and SS peptides in general in the avoid category for now. They are super interesting, super promising biologics. I’d just like to see a bit more data.