Greetings and welcome to the Satellos Six-Month TRAILHEAD six-month data conference call. At this time, all participants are in listen only mode. A question- and- answer session will follow the formal presentation. If anyone should require operator assistance during the conference, please press star zero on your telephone keypad. As a reminder, this conference is being recorded. I'd now like to turn the call over to your host, Dan Ferry, investor relations. Thank you. You may begin.
Thank you, operator. Before we begin, I'd like to remind you that today's webcast contains forward-looking statements. Such statements may include risks and uncertainties that could cause actual results to differ materially from those expressed and/or implied by these statements. For more information on such risks and uncertainties, please refer to the risk factors section of our annual information form dated March 27, 2026, which is located on our profile at www.sedarplus.ca and in our public filings on SEDAR+ and EDGAR. Any forward-looking statements represent our views as of today, July 8, 2026. We also note that today's results are interim six-month results for four patients, excuse me, four participants and the trial is ongoing. Now I'd like to turn the call over to Frank Gleeson, CEO of Satellos. Please go ahead, Frank.
Thank you, Dan. Welcome everyone to our call this morning. We're so excited to report the interim six-month results in TRAILHEAD. We know many on today's call have been anticipating this update. We so appreciate your interest in Satellos. Before I turn the mic over to my colleague, Dr. Wildon Farwell, to walk through the results, I'd like to point out that we see today's results as reaffirming our belief in the strategy that we developed for SAT-3247 to first demonstrate its potential for biological activity as well as its potential for benefit in the most underserved but in-need population, the adult population of patients living with DMD, then moving to a pediatric population for our placebo-controlled study.
This approach is allowing us to get an early, ongoing, building glimpse into our drug to meaningfully de-risk our program, to generate relevant data, which is allowing us more touch points with the regulators, of course, to provide hope for a greater spectrum of age groups of individuals living with Duchenne. We look forward to your questions this morning. I will now ask our CMO, Dr. Farwell, to take it from here. Wildon, over to you.
Thanks, Frank, good morning, everyone. As Frank mentioned, we are very encouraged by the six- months data from TRAILHEAD, which, as you will see, demonstrates stability or improvement across several important efficacy outcome measures with a clean safety profile consistent with previously reported data. These four participants are adults with Duchenne between the ages of 21 and 28 years of age, who completed the 28-day CL-101 study and subsequently enrolled in TRAILHEAD.
Adult DMD patients are among the most challenging patient population in which to evaluate treatment effects because the disease progression inevitably leads to muscle loss, fat infiltration, and reduced muscle satellite cell reserves as compared to kids with DMD, who we are currently evaluating in a separate study known as BASECAMP. In TRAILHEAD, participants were orally administered 60 mg of SAT-3247 five days on and two days off.
The primary endpoints are safety and tolerability, as well as biceps brachii fat fraction by MRI. Other endpoints include strength, function, spirometry, patient-reported quality of life, and biomarkers, among other measures. While this is an ongoing 12-month study, the data I am presenting today represents outcomes through day 140 in TRAILHEAD, or month six overall, for the four participants initially treated in CL-101. We anticipate reporting 12 months data in the fourth quarter later this year. Turning to slide four. We summarize a few key highlights, which we will cover in more detail momentarily.
As a reminder, SAT-3247 is an investigational agent and is not yet approved in any country or region. We believe data from TRAILHEAD continue to show a favorable safety profile, and after approximately six- months of overall exposure, demonstrate a decline in fat fraction as well as an improvement in upper limb total effort among all four participants, all while maintaining strength. Turning to slide five, which summarizes our safety and tolerability findings. As of May 18th, 2026, all reported adverse events in TRAILHEAD have been mild or moderate in severity, and we have observed zero serious adverse events, zero adverse events leading to withdrawal or discontinuation, and 100% treatment compliance.
Participants have achieved over 186 days of mean drug exposure across CL-101 in TRAILHEAD. These safety and tolerability findings are consistent with previously reported data, and we believe continue to strongly support the clinical development of SAT-3247 in DMD and other indications with serious muscle disease. Turning to slide six, one of the new exciting findings we are most encouraged by, change in muscle fat fraction as measured by MRI, which I will remind you is our primary efficacy endpoint in TRAILHEAD.
What you see on this slide is that all four participants show a decline or improvement in fat fraction of the biceps brachii muscle from TRAILHEAD baseline to day 140 in TRAILHEAD, with a mean improvement of 3.7 percentage points, from 49.7% at baseline to 46% at day 140. Importantly, declines or improvements were observed across all four participants with a range of 0.9%-6.2% over the five months of dosing in TRAILHEAD. To put that into context, published natural history data show that muscle fat fraction in adults with DMD typically increase or worsen by about 5.9% per year in the absence of treatment.
Rather than the disease-driven worsening in fat fraction, which we would expect to see in this population, we observed an improvement across all four participants. We believe this is a meaningful and encouraging objective signal of biologic activity for SAT-3247 in this difficult-to-treat adult DMD population. Turning now to slide seven. We looked at the real-world measure of upper limb activity called TE99C, or total effort at the 99th percentile.
TE99C, also referred to as maximum effort, is a continuous measure captured using the SYSNAV Syde device, a medical-grade wearable device widely used in clinical trials. Participants wear the device on their wrists and ankles to track movements while living their normal lives at home outside of the clinical trial setting. What you see here is that all four participants showed an increase in TE99C from CL-101 baseline to TRAILHEAD month six, with a mean improvement of approximately 5.5 J/kg from 16.1 J/kg at baseline in CL-101 to 21.6 J/ kg at month six, or a percent mean improvement of approximately 34%.
As with the fat fraction data on the prior slide, we think what's notable here isn't just the magnitude of the change, it's also that all four participants have improved. Because this is a continuous real-world measure of how people actually use their upper limbs day to day rather than a single point in time clinical assessment, we view this as another encouraging signal that complements and reinforces what we're seeing in the imaging data and adds further evidence of biologic activity for SAT-3247. Turning now to slide eight, muscle strength.
Across all measures of dynamometry, including handgrip strength and strength measured across the elbow and shoulder, participants demonstrated stability across the follow-up through month six of TRAILHEAD. Notably, the near doubling of handgrip strength first reported in the earlier 28-day CL-101 study was maintained through month six of TRAILHEAD, even though participants had been off SAT-3247 for roughly 7 months to 11 months between the end of CL-101 and initiating TRAILHEAD. Remember that in the natural history of adults with DMD, upper extremity strength is expected to decline over time.
Seeing stability across multiple assessments of strength and durability of that earlier handgrip improvement despite a treatment gap reinforces the encouraging, consistent picture of benefit that we are seeing across imaging, effort, and now strength. Turning now to slide nine, creatine kinase or CK, which is a well-established biomarker of muscle damage. Previously, we reported in CL-101 that we did not observe a consistent change in CK. What you now see is that among the four participants of TRAILHEAD, mean CK levels appear to drop and remain lower through 140 days of dosing in TRAILHEAD, representing a decline of 38% from their CL-101 baseline of 2,130 units per liter to 1,315 units per liter at month six of TRAILHEAD.
Previously, we have shown an improvement in several potential biomarkers of DMD using a proteomic analysis comparing levels at baseline and day 15 in CL-101. We are demonstrating a decline in CK across 12- 16 months, further demonstrating a potentially important biologic signal of SAT-3247 in adults living with DMD. Turning now to slide 10. Performance of the upper limb or PUL is a standardized clinical outcome assessment of the upper limb function. From TRAILHEAD baseline through day 140, two participants improved by one point on the PUL.
The other two remained stable. Across the board, we saw either improvement or stability with no participant declining in their overall score. In the natural history of DMD, upper limb function as measured by PUL is generally expected to decline over time, not to remain stable or improve. With six months of total dosing, we are observing adults treated with SAT-3247 remaining stable or improving in function, while adults with DMD would often worsen.
This adds another encouraging data point to the consistent pattern across biomarkers, imaging, effort, strength, and now function. Turning now to slide 11, and a patient-reported outcome measure, PedsQL- MFS, or Multidimensional Fatigue Scale, which quantifies fatigue, and in TRAILHEAD, we are using a version that has been adapted for use in adults. Reports directly from people living with DMD are important because they directly capture how they are experiencing day-to-day life, not just what we observe in the clinic. From CL-101 baseline to day 140 of TRAILHEAD, the mean PedsQL- MFS score increased by 6.94 points from 71.53- 78.47.
Again, this is an encouraging complement to the data we've already walked through because it suggests that the biologic changes we are observing may be translating into something adults with DMD can actually feel, specifically less fatigue and an improved sense of quality of life. Taken together with everything else that we covered in this presentation, this reinforces the consistency of the signal we're seeing across multiple objective and independent measures. Turning to slide 12.
We are fortunate to have real-world validation from a leading voice in the DMD field, Dr. Perry Shieh, professor of neurology and pediatrics at the David Geffen School of Medicine at UCLA, who has spent his career treating and studying patients with Duchenne, including adults, a population that is especially difficult to impact given the significant muscle and stem cell loss. I encourage everyone on the call to review Dr. Shieh's full comment in this morning's press release. Drawing on his extensive experience with both adult and pediatric neuromuscular patients, he views the consistency across strength, muscle composition, effort, quality of life, and safety as highly encouraging despite the small cohort size.
He also believes the improvement in fat fraction and total effort may be clinically meaningful, particularly in a population where continued decline, not stability or improvement, is the expected course. Coming from a clinician who treats these patients every day, this perspective reinforces our confidence in advancing SAT-3247 in both TRAILHEAD and BASECAMP. Turning finally to slide 13 and where we go from here.
As Frank noted in our press release this morning, we believe these six-month findings continue to demonstrate the potential of SAT-3247 in all people living with DMD, and in particular in BASECAMP, our study in a pediatric population with DMD. Because boys with DMD typically have more muscle mass relative to adults, BASECAMP may present an even greater opportunity to demonstrate the clinical potential of SAT-3247 in a clinical trial population. In terms of near-term catalysts, we remain on track to complete BASECAMP enrollment in the third quarter of this year, as well as initiate U.S. clinical trial sites for TRAILHEAD.
Looking ahead to the fourth quarter, we expect two important readouts, initial top-line data from BASECAMP, which we view as a key pediatric proof of concept study and a significant value inflection point for the company, and the 12-month primary readout from TRAILHEAD among these first four participants, which will also inform our thinking on potential engagement with the FDA on a path forward with SAT-3247. To summarize, we believe today's data further demonstrate biologic activity and encouraging clinical data reinforce a differentiated dystrophin-independent mechanism of action for SAT-3247 with a clear and near-term catalyst path ahead.
Finally, I want to thank all of the team members at Satellos who are working hard and tirelessly every day to conduct these high-quality clinical trials. I want to thank the DMD community for partnering with us on this journey. With that, I am happy to answer questions. I do need to leave shortly after 9:00 A.M. Eastern to give our presentation of this data at ICNMD. With that, I will turn the call back over to the operator for questions. Operator?
Thank you. If you'd like to ask a question, please press star one on your telephone keypad. A confirmation tone will indicate your line is in the question queue. You may press star two if you'd like to remove your question from the queue. For participants using speaker equipment, it may be necessary to pick up your handset before pressing the star keys. We ask that you each keep to one question. Our first question comes from the line of Joseph Schwartz with Leerink Partners. Please proceed with your question.
Great. Thanks, and congrats on all the progress. I wanted to ask about the potential read-through from TRAILHEAD to BASECAMP. Have you done any more response exposure analyses? Are the two patients, I think they were one and three, who had the greatest improvement in MRI fat fraction the same two who had the greatest improvement in TE99C? Thanks.
Thanks, Joe, for the question. We do believe that the data that we're seeing in TRAILHEAD gives us confidence about what we will be able to see in BASECAMP. We've not performed any additional correlation analyses looking at drug concentration and level of effect in TRAILHEAD. We do have the opportunity to do analyses like that within BASECAMP. As you'll recall, we previously showed that in the CL-101 study, the participants who had higher drug concentrations were the participants who had a greater improvement in their hand grip strength.
In BASECAMP, we're evaluating both the 60 mg and 120 mg dose levels. As far as your question about the two participants who had the greater improvement in muscle MRI, fat fraction, and then the TE99C. The participants who had the greatest improvement in muscle MRI, one of those participants was a participant with low baseline creatinine. One of the participants was a participant with high baseline creatinine.
As far as the TE99C, the two participants who had a higher level of function at baseline, both of those participants had higher baseline creatinine, and those participants actually went on to have a greater improvement in their TE99C. To me, this is all very encouraging and consistent with what I believe is the biology of both SAT-3247 and the disease itself. Again, we know that in patients living with Duchenne, there is a progressive loss of muscle over time, and this muscle is replaced by fat.
What we see is that the participants with the lowest muscle mass, as measured by baseline creatinine, they are more likely to have a higher fat fraction. The participants with more muscle mass are more likely to have greater function and are actually able to gain more function over the period of time of this trial. We believe it's all consistent with both the biology of the disease and how the drug is working.
Very helpful. Thank you.
Thank you. Our next question comes from the line of Kostas Biliouris with Oppenheimer & Company. Please proceed with your question.
Thanks for taking our question and congrats on the very promising data. Given that the MRI muscle fat fraction data are very promising here, very telling, can you elaborate a little bit on this endpoint, for example, whether it could be an approvable endpoint with a potential accelerated approval, and whether you would consider making it a co-primary or even a primary endpoint for your readout at the end of the year, given that you have a meeting with the FDA coming up? Thank you. Any color around this endpoint would be helpful. Congrats again.
Thank you, Kostas. We are very encouraged by the muscle MRI data. We do believe this is an endpoint that has been very well characterized within the natural history studies. In BASECAMP, we will be evaluating fat fraction within the vastus lateralis muscle in the leg. In TRAILHEAD, we are evaluating fat fraction within the biceps brachii muscle within the arm. Both muscles have been associated with function such that when fat fraction increases in the vastus lateralis, it is known that patients living with DMD are more likely to lose ambulation. They're more likely to lose function.
When fat fraction increases in the biceps, it's known that patients with DMD are more likely to lose hand-to-mouth function. They're more likely to lose function at the shoulder. This natural history has been gathered over a long period of time. In fact, it's part of the reason that other sponsors have actually evaluated muscle MRI in their clinical trials. We know the regulatory agencies are familiar with this endpoint.
We know that they're familiar with this natural history. In fact, in the guidance document for Duchenne, the FDA describes fat fraction as an endpoint. So we will be continuing to evaluate fat fraction in TRAILHEAD. It is one of our endpoints within BASECAMP. We have always said that we believe the data from TRAILHEAD may give us the opportunity to speak with regulators about a path forward in BASECAMP around accelerated approval if the data support that. So we will be considering our options on when to engage with the FDA around this and other data from these programs.
Thank you.
Thank you. Our next question comes from the line of Andy Grasselli with Guggenheim Partners. Please proceed with your question.
Hello, guys. Thank you for taking my question. Just a quick question around MRI. Specifically, what's the kind of the sensitivity of the assay, and what's the variability around that? Thank you.
Thanks for the question. Muscle MRI, this is a standard approach assessment using Dixon as the approach that is consistently used across the industry and across the natural history analyses. In this, several different slices were evaluated. This was an independent evaluation performed by a team who did not know the participant that they were evaluating.
The results that we're seeing are at baseline consistent with the natural history with the population that would be expected. What is inconsistent, different from the natural history is the change that we see over five months of dosing. We believe this is very encouraging, very supportive of the biologic activity. We will be continuing to evaluate this in TRAILHEAD and then look forward to evaluating the muscle MRI findings within BASECAMP.
Thank you. Looking forward to it.
Thank you. Our next question comes from the line of Yanni Souroutzidis with Cantor Fitzgerald. Please proceed with your question.
Hi. Good morning. This is [inaudible] on for Yanni. Thanks for taking my question, congrats on the update. Two questions from me. One is, what would you point people to focus on most in BASECAMP? Will you be pooling the dosing cohorts for running stats or be seeing those separately?
Thanks for the question. In BASECAMP, we have always believed that this is a population that has a greater opportunity to demonstrate benefit within the short period of time of a clinical trial. This is because in order for SAT-3247 to work, there needs to be muscle present. That muscle must want to have regeneration. There must be a signal to activate the satellite cells. Then SAT-3247 is able to influence the polarity of those stem cells to increase asymmetric division and increase muscle progenitor cell development.
In a young population with Duchenne, we know they have more muscle, we know that they have less fibrosis, and we believe this can translate then into an increased opportunity within a short period of time to show benefit. We have a number of endpoints that we're excited about within BASECAMP. Right now, it's set up to have dynamometry be the primary endpoint. We also have muscle biopsy, so we'll be able to see biologic activity within the muscle itself.
We have the muscle MRI. We also have SB95C, which is a similar assessment to the TE99C that's collected within TRAILHEAD, as well as [NSAA] and other more traditional functional assessments and PROs. We believe it provides a very comprehensive evaluation of the potential for function in a younger DMD population. We believe that overall, BASECAMP gives us the opportunity to have a data set that could support accelerated approval once we have discussions with the FDA and see how the data turn out.
Great. Thanks so much.
Thank you. Our final question comes from the line of Arthur with H.C. Wainwright. Please proceed with your question.
Hey, guys. Good morning. Congrats on the positive data. It's very impressive. Just one quick question on the TE99C. Do you guys have data for the three-month measurement for the TE99C? What's your thoughts on using this endpoint for a regulatory, like for the approval endpoint when you're talking to the agents for the non-ambulatory patient? Thank you.
Thanks for the question, Arthur. We don't have TE99C at the three months in TRAILHEAD for these first four participants. The first assessment in TRAILHEAD for these first four participants is the six-month assessment. As far as potentially utilizing TE99C as an approvable endpoint with the regulatory agency, TE99C has not been evaluated as often in the natural history as has SB95C. Sysnav is beginning to do more work with that. If you go to the Sysnav website, you can see posters where they have evaluated correlation between TE99C and the Brooke score, which is an evaluation of upper limb function, and they see correlation there.
We do believe that there is ongoing work with SB95C in the younger ambulant population, and that is an endpoint that regulators are becoming increasingly familiar with. This is an endpoint that Europe has agreed can be a primary endpoint in Duchenne. The encouraging data that we see with TE99C in the adults, we believe gives us confidence about potentially seeing a benefit with SB95C.
I will also say that right now we believe that the [inaudible] population is one population. We would not be looking for a separate approval in one portion of the population. Rather, we would be looking to have conversations with the agency about approval across the entire population once we see data from the completed BASECAMP study and continue to see data from TRAILHEAD over the next six months with the 12 months readout later this year.
That's very helpful. Thanks.
Thank you. Ladies and gentlemen, we've come to the end of our time allowed for question and answer. I'll turn the floor back to Mr. Gleeson for any final comments.
Oh, thank you, operator. Once again, thank you to the audience. We very much appreciate your interest in Satellos. I'll repeat again how excited we are by the data that we're seeing, which is a continuation in, albeit a small number of adults for patients. To see such consistency across not just the patients, but a variety of measurements increases our confidence in our drug and in the plans we have going forward.
To remind everyone, we're fully cashed up to be able to execute on our plans over the next couple of years through to the end of 2027. We are increasing our engagement with the FDA as a direct result of the data that we're generating. We're filled with a lot of optimism and I'm very proud of my team and where we've gotten to with our program. I'll turn it back to you, Dan, and thanks again for listening in.
Thank you. This concludes the news conference. You may disconnect your lines at this time. Thank you for your participation.