Good morning, and welcome to today's Disc Medicine Investor Webcast. I'm John Quisel, CEO here at Disc, and today we are delighted to provide a review of our initial data from the Phase two open-label BEACON trial. This is our first patient data from our trial of bitopertin in patients with erythropoietic protoporphyria, and we're delighted to say the data are positive. A few preliminaries before we get going. We will be making forward-looking statements, and we would encourage you to review these in context of materials we provide on our website and filed with the SEC. Additionally, bitopertin is an investigational agent and is not approved for use as a therapy in any jurisdiction worldwide. Today's agenda, I'll provide an introduction and brief summary of our data.
We'll be joined by Will Savage, Chief Medical Officer here at Disc, who joins us from the conference in Frankfurt, Germany. I'll provide closing remarks, then we'll move to a Q&A session. First, I'll provide key takeaways from this initial read of our BEACON trial data. I'm pleased to say we're seeing potent and consistent reductions in the levels of protoporphyrin IX, or PP9, greater than 30% at both levels tested. If you recall, this is the level of reduction that we expect and the literature predicts would lead to clinical improvements in light tolerance. In fact, we are seeing, even at this early stage, profound effects on sunlight tolerance. This is also measured in an improvement in patient's quality of life, the safety looks generally acceptable.
We're often asked whether bitopertin will cause a decrease in hemoglobin levels, and we see no effect on hemoglobin levels. Altogether, for an early read from this first open-label trial, the data are excellent. We're achieving really everything we expected to achieve at this point in the program. The main caveats are, of course, that this is open-label, there's no placebo group, and we're looking at a relatively small number of patients. Now, I'll just provide a brief background of the disease and our therapy, bitopertin. Erythropoietic protoporphyria, or EPP, is a rare, debilitating, lifelong condition characterized by extreme pain and damage to skin caused by light. It's a genetic disease. Prevalence is estimated at approximately 7,000-8,000 addressable patients in the US and Europe, and that includes a related disease called XLP or X-linked porphyria.
Recent genetic studies suggest the number may be higher. This disease is characterized by skin phototoxicity. As I mentioned, this brings on disabling pain attacks. There's also an element of hepato biliary damage that's progressive in many patients, leads to gallstones, liver dysfunction, and can rarely lead to liver failure. The driver of the disease is this metabolite called protoporphyrin nine. This is the last metabolite produced in heme biosynthesis. In these patients, the defect in the heme biosynthetic pathway leads to an accumulation of this metabolite, and this metabolite, PP9, drives all the pathology of the disease. In the skin, it reacts with light to become a free radical, causing damage and excruciating pain. In the liver, it accumulates and eventually causes liver damage as well.
This complex of symptoms leads to psychosocial complications and other complications as well. It's altogether a very severe disease driven by this central metabolite. Our approach is to use bitopertin. Bitopertin is an experimental therapy that inhibits the uptake of glycine into newly forming red blood cells. Why is this important? Glycine is the first metabolite consumed in the heme biosynthetic pathway. On this slide, you can see all the enzymatic steps, eight of them, moving from glycine through a chain of enzymatic reactions to protoporphyrin IX and then to heme. This, of course, is a key component, manufactured in large quantities in each newly forming red blood cell. In the disease, the enzyme ferrochelatase typically is defective, leading to a buildup of protoporphyrin IX.
The premise of bitopertin is that by decreasing the flow of glycine through this pathway, we can decrease the accumulation of this toxic metabolite. The literature would suggest that this disease is very sensitive to the level of PP9 present in each patient. While there are no other therapies that are able to reduce PP9 levels, there are a number of studies that suggest that if you can reduce the level of PP9 by greater than 30%, there's a significant chance that you'll have a profound effect on the patient's photosensitivity, and of course, some effect on liver health as well. I won't review these studies in detail, but the papers are on our website for your review. Again, our target is to get a greater than 30% reduction in PP9 levels.
We do come to our clinical program with preclinical evidence in hand. We have been able to test bitopertin in both cellular and mouse models of disease. In the left and center panel, we can see the effects of bitopertin on PP9 levels in mouse models. We generally see a decrease in the range of 45%-75% in these animal models, and these data have been published at the American Society of Hematology meeting over the past couple of years. The right-hand panel, we show that bitopertin in reducing PP9 levels is also able to lead to a reduction in liver damage, providing a connection in this preclinical setting between PP9 reduction and the clinical impact of the disease in these animal models.
I should mention that these studies were all performed in collaboration with researchers at Boston Children's Hospital. With this preclinical data package, and we have a safety database for Bitopertin, numbering over 4,000 patients, we were able to initiate two phase two clinical trials in 2022. The first is called BEACON. This is an open-label study conducted in Australia, enrolling both EPP and XLP patients with a number of patients designed to be about 20. We have two dose groups, a 20 mg dose and a 60 mg dose over a six month period. We're also running a placebo-controlled trial called AURORA. This is 75 patients in three groups. We now have a placebo group here. This trial is being conducted in the US and is projected to deliver data later this year.
Today, our data package, being presented at EHA is from the BEACON trial. It's the first look at some of this open-label patient data, and, as you'll hear in a moment, we're looking at endpoints, including blood protoporphyrin nine levels, as well as various measures of light tolerance and safety. With that introduction, I'll hand it over to our Chief Medical Officer, Will Savage.
Thank you, John. I'd like to start by reviewing the enrollment in BEACON. As of May eighth, a total of 15 subjects have been enrolled. As a randomized trial, there are approximately equal numbers in the 20 milligram and 60 milligram dose groups. Nine subjects have completed through day 43. One subject has completed the 6-month duration of the study. Shown below is the schema of the study visits. As a reminder, study measures include changes in blood protoporphyrin IX levels, measures of light tolerance, time to prodromal symptom, and safety and PK. The primary endpoint in this trial is the % change in whole blood metal-free protoporphyrin IX. We're happy to report that bitopertin reduced whole blood metal-free PP9 in both cohorts. These reductions were dose-dependent and observed across a broad range of baseline whole blood PP9 levels.
In the figure on the left, in the solid line is the aggregate protoporphyrin IX response in both dose groups, showing a greater than 40% reduction in PP9. The dashed purple line is the 20 milligram dose group that had a greater than 30% reduction. The dashed yellow line is the 60 milligram dose group, which had a greater than 50% reduction. On the right are shown individual protoporphyrin IX data from the subjects with available data, we see a consistent and dose-responsive reduction in protoporphyrin IX. You'll note on the right-hand side of the figure that there are two subjects who have either completed or come close to completing the study, we will take a closer look at these two subjects in the subsequent slides.
This is a slide presenting data on time to first prodromal symptom, which is a measure of light tolerance. This endpoint is assessed through patient sunlight challenges. People with EPP experience a prodrome or early warning symptoms upon sunlight exposure before a full phototoxic reaction occurs. These prodromal symptoms can be aborted when people extract themselves from the sunlight, and this time in sunlight until this prodrome occurs, can be measured with these sunlight challenges. That's what the figure below is presenting. In red font are challenges that result in a prodrome, and in blue are challenges that were prodrome free. Looking at the left-hand side of the figure at baseline, this subject had a 4.5-minute time to prodrome symptoms, and then after day 20, something remarkable happened in that on all subsequent challenges.
in the study to date, this subject was unable to elicit a prodrome. While this endpoint is called a time to prodrome, we actually didn't see any prodromes with these challenges for most of the time on the study. Highlighting day 88, this subject had more than 6 hours in sunlight without a prodrome, and that's quite a long time. Essentially, this, the subject stayed outside as long as was feasible before moving on to other things. On the right-hand side of the figure is shown the baseline protoporphyrin IX level, a relatively high level, a 30% reduction in this level on day 71, and a 38% reduction on day 154. This is a subject on the 60 milligram dose group. Similarly, this patient became unable to elicit a prodrome with sunlight challenges as the study went on.
Again, denoted by the blue bars in the figure. At baseline, this subject had a time to prodrome of 1 and a quarter minutes. By day 74, sunlight tolerance that was measured was over four hours without a prodrome. On the right are shown the baseline protoporphyrin IX level, and at day 71, this subject had a 59% reduction, and by day 154, a 72% reduction. Here, we're presenting other measures of light tolerance, but before getting into the data, it's important to understand the ways in which we're measuring light tolerance in the study. On a daily basis, subjects are entering symptoms and minutes in light with an electronic diary. Then weekly, we ask subjects to go outside and do a sunlight challenge, and then at any point throughout the study, subjects record when they have a full phototoxic reaction.
Overall, in aggregate, across all subjects, bitopertin led to a 96% reduction in the full phototoxic reaction rate as compared to baseline. Looking at the figure on the left, symptom-free days, as recorded in the daily diaries, during baseline, only 25% of days were symptom-free, versus 75% of days while on bitopertin. On the right, all subjects at baseline had sunlight challenges that involved a prodrome, so there were no prodrome-free sunlight challenges. Looking at all subjects on study, half of sunlight challenges were prodrome-free while taking bitopertin. Here, we're looking at two measures of aggregated data on light tolerance. On the left is looking at all subjects in the study and their time to prodrome assessments over the course of the study. At baseline, the average time to prodrome measurement was 25 minutes.
Again, looking at all subjects, and over the course of treatment, there is a manyfold increase in that mean time to prodrome. On the right is shown weekly total time in sunlight. These are data from the daily diaries, where we're looking at the time spent in sunlight, and we see that it increases every week throughout the study. Note that in this figure, for any missing diary entries, we conservatively impute zero time in sunlight. We had a number of measures of quality of life in this study. First, the Patient Global Impression of Change, for which we have data through day 43. 10 out of 10 participants reported that their EPP was much better or a little better. On the Patient Global Impression of Severity, nine out of 10 participants reported that their EPP was mild or not at all severe.
We also have a questionnaire that probes into multiple aspects of the patient experience. On the question of, "In the last seven days, how much did having EPP impact your overall quality of life?" we are reporting here the last observation captured in the study. Overall, the majority of respondents say that their EPP is impacting their quality of life less. I'd like to highlight that in the top right of the figure, that the two subjects who have been in the study the longest, report on their last assessment that EPP is not at all impacting their quality of life, and all the other respondents are only at day 43 in the study, yet a majority of them still show less of an impact of their disease. Regarding safety and tolerability, there have been no serious adverse events.
There have been no changes in hemoglobin levels over time, shown in the figure on the right, with the 20 milligram and 60 milligram dose groups being superimposable. There have been no discontinuations or dose reductions, and all treatment-emergent adverse events are grade one and transient, with a median time to resolution of only half a day. Of the TEAEs reported in more than one subject, the only observations are dizziness and headache, which are known side effects of bitopertin from prior clinical trials. Now I'd like to hand it back to you, John. Thank you.
Thanks, Will. To summarize our findings today, you saw the data that bitopertin at both the 20 mg and the 60 mg once-daily dose are successfully decreasing protoporphyrin IX levels below that 30% threshold, and markedly so at the 60 mg dose. We're seeing this translate into early signs of increased tolerance of sunlight. In fact, it is remarkable, the two patients at the 20 and 60 mg doses, respectively, showing that after about two months on study, there's no longer, in most cases, a detectable response to sunlight. This is then reflected in the quality of life scores that Will presented, where you saw those two patients reporting, essentially no burden of disease, in their quality of life anymore. The safety, all appears to be acceptable at this point in our development.
collectively, I think this is a very exciting set of initial data, and we're looking forward to presenting further data from both our trials in the future. To talk about our development status and upcoming milestones, in the EPP indication, the BEACON trial, you can see we've already enrolled 15 patients as of our last cutoff date. We expect to have data from all subjects to be presented by the end of the year. The AURORA trial is progressing well. We expect to have the complete data by the end of this year, with presentation likely to happen early in 2024. We do have additional milestones. As we've discussed in the past, we believe bitopertin and its mechanism of controlling heme biosynthesis has the potential to provide a therapy for other indications in the hematology space.
We do expect to be initiating an IIT in Diamond-Blackfan anemia, sponsored by the NIH, and that startup is expected in the middle of this year. Meanwhile, we have planning underway for studies in yet additional indications for this program. Thank you all for your attention today, and now we will open it up for Q&A.
All right. Our first question comes from David Nierengarten of Wedbush Securities, who asks, "Is there a biological basis for a patient having some prodromal symptoms after several days without those symptoms?
Yeah. Hi, this is John Quisel.
Hi, this is Will.
Will, please go ahead.
Yeah. Sure. Thanks. Thanks for the question, David. I'd like to move back to slide 16. There is a phenomenon in EPP called priming, where cumulative sunlight doses over consecutive days can decrease the threshold of a phototoxic reaction or prodrome on a subsequent day. If we look at this subject in the study, who is actually doing sunlight challenges much more frequently at times than once a week, sometimes you can see that particularly earlier in the study, like day 29, 30, 33, 35, 36, and there's increased light exposure over multiple days that are clustered lead up to that day 35 and 36. It's possible that a cumulative exposure led to those prodromes.
Similarly, later on in the study, days 106, 116, particularly 116, the subject got a lot of sunlight on 113, 114, 115, and then had a prodrome at day 116, but still was, many, manyfold, increase in light tolerance over baseline.
Great. Our next question comes from Thomas Smith of SVB Securities. You can go ahead, Tom.
Thanks for taking our questions, and congrats on the data. Just a couple on efficacy here. I think, you know, maybe first for the two patients you highlighted who experienced the light tolerance improvements, can you just help maybe contextualize how typical these patients were in terms of their baseline PP9 levels and baseline symptoms? Did they have any other complications from their EPP? Secondly, I think you were also collecting some measurements on hepatobiliary markers and things like liver stiffness. Can you just comment on whether you're seeing anything on those measures in this early data set? Thanks.
Thanks, Tom.
Oh, sure. Thanks, John. We're, on the second question, we did not do an interim cut to look at hepatobiliary markers. Those are things that we expect to change over a longer duration. We'll be looking at those at end of study. At baseline, these the first two subjects by exclusion, they cannot have significant hepatobiliary disease, they didn't have that comorbidity. Otherwise, there's nothing remarkable that I recall about those two subjects. Regarding their baseline light tolerance, they are on the more severely affected end of the spectrum. As a group, published data show approximately a 20-30-minute mean daily light tolerance.
And their PP9 levels are representative, one being above, you know, the median, the other being below the median.
Okay, got it. That's really helpful. Then maybe just, one follow-up question. Just curious if you've done any, I guess, early analysis correlating the individual patients' reductions in PP9 levels with improvements in symptoms and quality of life, I guess, within the context of this study? I guess what the plans are for... If you haven't done those analysis, what the timelines are for doing those sorts of, analyses.
Yeah. Those are, of course, very interesting analyses to do. We did not do that on such a small data set, particularly with the N and the degree of follow-up. Those will be done with end-of-study type data.
Got it. That makes sense. Thanks for taking the questions, guys. Congrats on the data!
Thanks, Tom. Our next question comes from Ben Burnett of Stifel.
Hey, great. Can you hear me okay?
Yes.
Excellent. I wanna just ask if you could put into context the dizziness signal that you saw. Maybe just talk about what is grade one dizziness, and I think you mentioned this was a transient phenomenon.
Sure. So grade one is mild, and it's meaning it's not having a meaningful impact on the person and does not require any significant intervention. I think the fact that they are grade one and transient tells us everything we need to know about it. In other words, it's something that people notice, and it goes away quickly, but it doesn't have any other sequelae beyond that.
Understood. Okay. Are patients, are they able to take, you know, anti-dizziness medications? Is that allowed on the study?
Sure. Any supportive medication is allowed, but hasn't been necessary.
Excellent. Okay. Okay. One other question, just around the total weekly time in sunlight. I guess, could you contextualize that with the sort of Scenesse endpoint, just in terms of the definitions of those endpoints? Are they fairly relatable?
What we are reporting here is on the weekly total time is just that, the total time. The endpoint that Scenesse used for approval is total time in sunlight from 10:00 A.M. to 6:00 P.M. on days without pain. There are those two other conditions that need to be included in the analysis to make a comparison. With an interim cut of the data, we didn't have the time to do that level of analysis. This is not... it's related, but not directly comparable to Scenesse data.
Okay. Understood. Well, thank you for taking the questions, and, congrats on this update.
Thanks, Ben.
Okay, our next question comes from Malcolm Hoffman of BMO. Malcolm, you can go ahead.
If there are technical challenges, perhaps we should move to the next question and come back.
Yes. Yes, we can. The next question we have is from Rami Kalla from Life Sci Capital.
Hey, guys, can you hear me?
Yes.
Just going off a previous question, and I know it's a small sample size, but any reasoning as to why the rates of dizziness and headache were higher in BEACON compared to previous studies with bitopertin?
Sure, I can take that, John. There are, I think a couple of reasons. You mentioned the small N. I think there are a couple other things perhaps going on. One is in particularly with mild adverse events, in any clinical trial, there tend to be different thresholds for reporting minor side effects. It could be with only two sites that there are, you know, differences in sensitivities of reporting, you know, things that may or may not reach the threshold for reporting for an individual investigator. I think it'll be important to look at, of course, larger N and AURORA data with a larger number of sites to get a better estimate. I think the important thing here is that the...
Again, these effects are transient. Nobody discontinued drug, which would be the first level of intervention to either dose reduce or discontinue if they, because it is a known side effect, and they were transient and not significant, so they didn't feel the need to do that. These, I'll just add one other piece. These tend to occur in the beginning of initiating treatment and don't recur. When we're looking at those percentages of the, you know, how many patients have these symptoms, it's transient, generally once, and then, you know, we have subjects going out to 6 months, where it's not a recurring issue.
Got it. Makes sense. Then another quick one from me. BEACON was conducted in Australia, whereas AURORA is enrolling in the U.S. I guess, do you expect seasonality or location of sites to have a chance to confound data to a certain degree?
I don't think that it's gonna have a meaningful impact on the data. Mitsubishi, who's developing dersimelagon, as an oral melanin-enhancing agent, published an analysis last year looking at seasonality of enrollment and found that it did not have an impact on their efficacy data. You know, this is also true in talking to KOLs that, you know, patients have symptoms year-round. They can get light sensitivity, of course, in sunny spring, summer, fall months. In winter, there tends to be more reflected light, particularly where there's ice and snow. Actually, for some patients, winter is the worst time of the year, because these phototoxic reactions most commonly occur on the face and hands, which are generally exposed year-round.
Got it. Makes sense. Thanks for taking my questions, and congrats on the update as well.
Thanks, Rami.
We have Malcolm's question, which is: At what point do you think we are seeing peak improvement in patients? Looking at some of the sample patients, you noted that after about three weeks, a patient no longer suffered prodromes. Even beyond three weeks, we seem to see continued PP9 reduction. What are your thoughts there?
Will, you wanna go ahead?
Sure. Like John mentioned in the introduction, you know, the literature suggests that after a 30% or greater reduction in PP9, you get complete or near complete remission of light sensitivity. I think once you cross that threshold, it becomes, you know, These data are telling us that we're getting success in terms of that near or full remission of light sensitivity. I think once you pass that threshold, I think it's hard to quantify, you know, what's the difference between the 30% reduction, 40% or 50% means, given the data that we have now.
Great. Our next question comes from Kristen Kluska of Cantor Fitzgerald.
Hi, good morning. Can you hear me okay?
Yes, we can hear you.
Perfect. Let me also add my congratulations to the team for these data. While I recognize by definition that prodrome is early signs or symptoms of an illness, did you notice any changes in the trial relative to what those initial precursor symptoms were, and then the degree of them? These are patients who weren't even used to being in the sun for one to four minutes. Wondering if there were any changes that were observed on that front with them spending considerably more time in the sunlight?
Sure, sure. Thanks for the question. I, it is an interesting question that we are capturing data to answer that in our daily diaries. It was not part of this analysis. It will be something that, at, after the conclusion of the study, we'll be able to present on.
Okay, thank you for that. I know ahead of this data, you talked about that 30% being the bar of clinical meaningfulness in terms of PP9 reductions. Do you have a sense of what anything greater than that correlates to additional time to first prodromal symptoms or other factors, especially factoring in the different baseline levels of these patients?
Yeah, this is related to one of the earlier questions. Given that, I think it's best done with when we look at the maximal reduction of all patients and have their complete light tolerance information. That's an end-of-study type of analysis, which we did not do for this for this interim look.
Okay. Thank you.
We have a question, a couple of questions from Jeffrey Hung from Morgan Stanley. His first one is: With treatment duration ranging from 18 days to six months in the current cut of data, on average, how long did it take for patients to reach over 40% reduction in PP9?
Well, go ahead. I think it's actually on the slide right here.
Yeah. Yeah. I pulled up the slide from the presentation, showing we don't have a hash mark exactly at 30, but you can see the reduction. Generally, crossing that 30 threat occurs within by one month in both dose groups.
Great. The next question from Jeff is: For the PGIS measure, how did the patient's response of mild EPP or not at all severe EPP differ from what they reported at baseline?
Sure. At, at baseline, there were four subjects who characterized their severity as moderate and two who characterized it as severe. That's 6 people in the moderate/severe. We have improvement. Just to clarify, the not at all is less than mild on the scale. It goes from not at all to mild, moderate, severe, to very severe.
The last question from Jeff: Were you surprised by the patient on 20 mg that didn't report a prodrome during any sunlight challenge after day 20, since this was much earlier than day 120 for the 60 mg patients? How much of that is due to differences in severity of disease at baseline?
I don't think it's due to severity of disease at baseline. I think, you know, I think when we look at, for example, the 60-milligram patient , I don't think we need to mark the starting point of improvement at the time of the last prodrome in this figure on day 116 or, you know, 106, 116, and then say, "Oh, the improvement started on day 120." These red bars are occurring in the context of significant overall improvement, and what we're recording here is only a prodrome, which is not a phototoxic reaction. I think, you know, improvement in both subjects started earlier in this subject. You know, you see something significant starting at day 29.
We talked about the potential of, you know, overexuberance, perhaps, and, you know, a lot of sunlight challenges that decrease the time to prodrome later on in the day 30 to 40 range. So it, to me, qualitatively, it maps with the reduction in PP9. Looking at the high-level trends, they're both achieving what we, what the literature suggested we would see is that full remission or near full remission of light sensitivity.
Great. Our next question is from Danielle Brill of Raymond James. You can go ahead, Danielle, if you can hear us. Okay, we can move on to Douglas Tsao of H.C. Wainwright.
Hey.
Can you hear me?
Okay, great. Thank you, and congrats on the data. I was just curious, if when you think about over the course of the study, for some of the patients who have been on bitopertin for longer, obviously we're seeing significant increases in their light tolerance. I'm just curious, from the diaries or your recording, are there meaningful lifestyle changes that some of these patients are making? Just how much does that sort of reflect the increases? 'Cause obviously, there seems to be a time response here. Is that, do you think, physiologic, or do you think that some of this is just a reflection that as patients got more comfortable, they tended to just incorporate things in their lives that allow them to be outdoors more?
John, I'll take that. Well, I think as adult patients, they've already incorporated all the adaptations into their lives during the baseline assessment. Their lifestyle is already baked in, and, you know, any change after dosing, you know, on bitopertin would be, you know, due to the increased light tolerance and what their... you know, how they adapt thereafter. We're only recording, you know, time, the different measures of time, the rates of phototoxic reactions. There are other measures of quality of life that we're assessing as well. We don't have granular data on like, you know, the mechanics on a day-to-day basis, what's changing in terms of their routines and so forth.
I think, you know, over time, that as, a narrative may emerge about that.
Also, in terms of the liver function, , I understand given the number of patients and the types that enrolled in BEACON, you didn't necessarily have great comparisons, or certainly at this point. Do you expect to see patients with some liver impact due to their disease in AURORA? Do you think we will get some sense of that, you know, bitopertin's effect on liver function in the either study?
Well, you know, we don't have. As I mentioned before, we need to look at longer-term data to really assess changes in liver function. Up till now, nobody's been able to do that experiment of chronically reducing PP9 levels, so we don't know when, if there is an effect, when that would read out. Certainly can't say whether it would show up in AURORA or not. I will highlight that we do have a global open-label extension study in which assessing hepatobiliary disease using the same endpoints as in BEACON is being set up for all these participants. We will be able to look over time course of years and not just months.
Okay, a final question from me. Just given this data and how dramatic the improvement is, certainly relative to, you know, if we wanna call Scenesse standard of care , have you considered going to the agents FDA and seeking Breakthrough designation?
Sure. T hat's a potential question that anyone could always ask at the end of phase 2. W e will have, of course, a meeting at the end of AURORA and present both BEACON and AURORA data to the agency and, you know, discuss what potential further development looks like.
Okay, great. Thank you. Congrats.
Thanks, Nick.
We have the questions from Danielle Brill of Raymond James. Her first question is: Given these patients aren't reaching a prodrome, at what point are we simply measuring their personal desires to go outside? Is time to prodrome the best measure to capture the benefit? What is the best measure to reflect treatment benefit?
John, I can take that. I think that in the protocol, there is no instruction to stay in the sunlight challenge, to stay out for a prescribed minimum amount of time if there is no prodrome. I think the differences in durations of prodrome-free sunlight challenges do reflect personal choices. T o put it in perspective, the amount of time , these, the, you know, we all are really indebted to the participants in this study. T hese sunlight challenges are many hours, and I certainly don't have the time to do that. I think it just highlights the commitment of these patients to the study, which, you know, of course, we're very grateful for. I think in terms of how else we can measure it, I'll say, you know,
We're creating new territory here, you know, we set up the study as a time to prodrome, anticipating that we would get a prodrome because that's what the disease is. The fact that we're seeing so many challenges without a prodrome, I think is a measure in and of itself of efficacy. If you combine it with the fact that this is, you know, basically at the outer limits of what a normal person can feasibly do in a day, it's like a transformation metric of how many times can you go out in the sun as long as you, is feasible for your life and have nothing happen? I think that's informative in and of itself.
Her second question, which is the last question we have for today. She said: "You mentioned dizziness effects are transient and tend to occur at the beginning of treatment. Could this be mitigated with a dose titration?
Yes, thanks for the question. It potentially could be. It's not something that we assessed in the study. I think, again, the fact that we did not have to dose reduce anybody thus far in the study, it indicates that this is tolerable. W hat I tell my team at Disc is, you know, with my seasonal allergies, I take antihistamines that do cause some dizziness, but I still take them because they work. I'm not so there's...
I think just I say that to put it in perspective, the grade one nature that's being reported, these are mild, and if patients are deriving benefit, it seems like there's not necessarily a need to change tack on our dosing strategy, but it's certainly one that we have considered and would, and, you know, explore if it were if those AEs became an issue for patients.
All right. I think that concludes the Q&A session for today. Thank you, everyone, for your attention and your time. Needless to say, we're excited to see further data from both the BEACON and AURORA trials unfold as we come into the end of the year, and looking forward to what that shows. Thanks again, and goodbye.