Aptinyx, Inc. (NASDAQ:APTX) Q1 2022 Earnings Conference Call May 12, 2022 5:00 PM ET
Pat Flavin - IR
Andy Kidd - CEO
Ashish Khanna - CFO
Kathryn King - SVP of Clinical and CMC operations
Harald Murck - VP of Medical and Clinical Affairs
Conference Call Participants
Ritu Baral - Cowen
Charles Duncan - Cantor Fitzgerald
Myles Minter - William Blair
Good afternoon, and welcome to the Aptinyx First Quarter 2022 Financial Results Conference Call. [Operator Instructions] Please be advised the call is being recorded at the company's request.
At this time, I would like to turn the call over to Pat Flavin, Senior Manager of Corporate Development and Investor Relations at Aptinyx. Pat, please proceed.
Good afternoon, everyone, and thank you for joining us on today's conference call to discuss Aptinyx' first quarter 2022 financial and operating results. We invite you to visit the Investors section of the Aptinyx website to view our press release describing financial results and business highlights from the first quarter of 2022. On today's call, Andy Kidd, our President and Chief Executive Officer, will discuss our business and clinical development progress; then Ashish Khanna, our Chief Financial Officer and Chief Business Officer, will review our financial results.
I would like to remind everyone that statements made during this conference call will include forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, which involve risks and uncertainties that can cause actual results to differ materially. Any forward-looking statements are made only as of today, and we disclaim any obligation to update these forward-looking statements. Please see the forward-looking statement disclaimer in our financial results release issued this afternoon and the risk factors in the company's current and subsequent filings with the SEC.
It's now my pleasure to turn the call over to Andy.
Thanks, Pat. Good afternoon, everyone, and thank you all for taking the time to join us on today's call. The past few months have brought some challenges but also great progress for Aptinyx. I'd like to start by acknowledging the disappointing results of our Phase IIb study of NYX-2925 in painful diabetic peripheral neuropathy that we announced in early April. We also announced shortly after those results that we were temporarily pausing the initiation of our second Phase IIb study of NYX-783 in PTSD evaluating the 150-milligram dose.
This was done in order to extend our cash runway and to enable us to focus resources on our other Phase IIb study of NYX-783 in PTSD evaluating the 50-milligram dose. This step, along with some additional prioritization of resources aligns our end of Q1 cash balance of $100 million to enable data readouts from each of our 3 ongoing Phase II programs over the next 18 months.
I'm very happy to say that this broader pipeline remains fully on track. And over the last few months, we have made meaningful progress across all of our other programs with NYX-2925 in fibromyalgia, with the 50-milligram dose of NYX-783 in PTSD and with NYX-458 in cognitive impairment. We, therefore, poised to reach several major milestones in the months ahead.
Thanks to our team's continued excellent execution, we currently expect data readouts from NYX-2925 in fibromyalgia in July or August of this year, from NYX-458 and cognitive impairment in late Q4 of this year or Q1 2023 and from NYX-783 in PTSD in the second half of 2023. Let's discuss our clinical programs in more detail beginning with NYX-2925.
We began 2022 with NYX-2925 under evaluation in 2 chronic pain indications, painful diabetic peripheral neuropathy, or DPN, and fibromyalgia. As I mentioned, in April, we announced the results from our Phase IIb DPN study. Unfortunately, the study did not meet its primary endpoint of separation from placebo on the 0 to 10 NRS pain rating scale at 12 weeks compared to baseline. Overall, the data did not show a clear clinical benefit of daily dosing of 50 milligrams of NYX-2925 relative to placebo and do not justify a path forward in this DPN indication. This result was obviously very disappointing and certainly not what we have hoped for.
We based the Phase IIb DPN study on data and analyses from our previous Phase IIa study in DPN. We, of course, always knew that pain and DPN is initiated by an underlying progressive peripheral pathology. But we had a biological hypothesis supported by data from our previous study that super spinal brain based pain processing abnormalities become a significant characteristic over time in DPN. This led us to evaluate the centrally acting mechanism of NYX-2925 in a specific subset of longer disease duration in DPN patients in the Phase IIb study, each of whom had experienced neuropathy symptoms for 4 or more years.
Since the data from this study suggests that even long-standing pain originating from peripheral neuropathy is not an appropriate disease for our mechanism to target, we made the decision to discontinue our development in painful DPN going forward.
NYX-2925 is also currently being evaluated in a Phase IIb study in patients with fibromyalgia. In contrast to painful DPN, fibromyalgia is not classified as a peripheral neuropathy and is instead widely thought to be a centralized pain state in which super spinal pain processing abnormalities arising in the brain are a primary characteristic.
Based on prior preclinical and clinical data, we've shown that NYX-2925 operates by modulating NMDA receptors in key brain regions responsible for the cognitive control of pain and pain perception which presents a compelling biological rationale for evaluating NYX-2925 as a treatment for fibromyalgia. Fortunately, we will not have to wait long for the data from this Phase IIb study in order to determine if these differences in underlying biology and mechanistic rationale compared to DPN can yield a different positive result.
The Phase IIb study in fibromyalgia completed enrollment in February of this year and is on track to report results in just a few months' time in July or August. The study is assessing NYX-2925 as a monotherapy without other concomitant analgesics over a 12-week treatment period. We feel these design choices are in line with regulatory requirements for future pivotal studies. We're testing daily dosing at 50 milligrams of NYX-2925, a 100 milligrams of NYX-2925 or placebo over the 12 weeks of treatment.
The primary endpoint in the study is the change from baseline to week 12 in patient-reported average daily pain averaged over a week and evaluated using the 0 to 10 Numeric Rating Scale or NRS. Alongside changes in average daily pain, additional endpoints will also measure the impact of fibromyalgia symptoms on daily function as well as changes in other symptoms, such as fatigue and sleep. The study is powered to detect an effect size that is clinically meaningful. Depending on the degree of variation seen with pain scores, that powering would be consistent with somewhere between 0.5 and 0.7 difference or greater between NYX-2925 and placebo on the 0 to 10 NRS scale.
Next steps following this study would include an end of Phase II meeting with FDA to discuss requirements for Phase III and NDA. We remain optimistic about this program, not only because of the strong biological rationale and precedent clinical data supporting its development but also for the opportunity to deliver a novel therapeutic solution to the over 8 million underserved patients living with fibromyalgia in the U.S. alone.
Let's move now to our next clinical program, evaluating NYX-783 in patients with PTSD. In December of last year, we initiated a Phase IIb study evaluating 50 milligrams of NYX-783 versus placebo. Study will enroll approximately 300 patients and evaluate them over 10 weeks using the CAPS-5 total score as the primary end point. The 50-milligram dose level of NYX-783 was selected based on the signal seen with that dose on the CAPS-5 scale over just 4 weeks of treatment in our previous Phase IIa study. Certain design parameters were incorporated in our follow-up Phase IIb study to help mitigate potential placebo responses and the overall design was finalized following a Type C meeting with the FDA to discuss the requirements for a pivotal study in this indication.
Based on early enrollment trends in the study, we expect to be able to report data in the second half of 2023.
We had also planned to initiate a second Phase IIb study to evaluate a higher 150-milligram dose of NYX-783 in patients with PTSD with a design very similar to that of the 50-milligram study. As I mentioned previously, we announced last month that we will temporarily pause the initiation of this 150-milligram Phase IIb study. Decision was driven by 2 main factors. First is the ability to preserve capital and enable our existing cash balance to deliver readouts from each of our other in-process clinical trials. The second is the ability to focus our efforts in PTSD on the 50-milligram study.
We had experienced a few challenges in initiating clinical trial sites on schedule in our PTSD studies due to a number of other studies in this indication being conducted in the U.S. across the industry. While we believe we've addressed these challenges, focusing our efforts should additionally derisk our ability to enroll a 50-milligram study within our planned time lines.
At the time of the pause, the 150-milligram study had not yet begun screening or enrolling patients. A number of the sites that were planned to contribute to the study will now shift their focus to the 50-milligram study.
We remain enthusiastic about studying the higher 150-milligram dose in this indication, and we'll make the decision to recommence the study as soon as we believe it makes financial and operational sense to do so. In addition to our progress in the clinic, we've also published additional preclinical data, demonstrating the positive effects of NYX-783 in models relevant to PTSD in the April edition of the Journal Molecular Psychiatry. This data further characterizes the therapeutic potential of NMDA receptor modulation to treat the learned fear and stress commonly associated with PTSD.
These preclinical data were also recently presented during a symposium discussion at the Society of Biological Psychiatry Annual Meeting in New Orleans earlier in May, and they will also be presented at the upcoming American Psychiatric Association Meeting later in the month.
Let's move on to NYX-458, our product candidate in development for the treatment of cognitive impairment associated with Parkinson's disease and dementia with Lewy bodies. Enrollment in our exploratory Phase II study in this indication has progressed at a steady rate since the start of the year. We continue to expect to report data either towards the end of this year or in the first quarter of 2023. This is a first inpatient study designed to assess safety and to detect a signal of the activity of NYX-458 on measures of cognitive performance. While the study is exploratory and primarily signal finding, we believe it is robustly designed to detect a therapeutically meaningful signal.
The study is a double-blind, randomized parallel design study planning to enroll approximately 100 patients that will receive daily dosing of either 30 milligrams of NYX-458 or placebo over a 12-week treatment period.
Given the novel mechanism of NYX-458, we're evaluating multiple cognitive endpoints in the study in order to characterize the activity across the critical cognitive domains of attention, memory and executive function. Not only are these domains characteristic of cognitive impairment in Parkinson's disease and dementia with Lewy bodies, but they are known to be an MDA dependent phenomenon.
This program represents an exciting opportunity to address a major unmet need and cognitive impairment, and we hope the data from this study will be a significant step towards achieving that goal.
With that, I will now turn the call over to Ashish to review our first quarter financial results.
Thank you, Andy. Beginning with the balance sheet. We ended the first quarter of 2022 with $100.2 million in cash and cash equivalents compared to $106.1 million at the end of 2021. Our Q1 2022 cash figure was inclusive of $10 million from the second tranche of our capital credit facility, which we drew down in March. As Andy outlined earlier, with the recent cash conservation measures on our PTSD program, we expect our current cash balance to provide extended operating run rate into 2024.
Over the course of that runway, we expect data readouts from each of our 3 ongoing clinical studies.
The majority of our spend during the quarter was focused on research and development related to our ongoing clinical studies across chronic pain, cognitive impairment and PTSD. R&D expenses were $13.6 million for the first quarter of 2022 compared to $10.3 million for the same period in 2021. We reported G&A expenses of $4.9 million for the first quarter of 2022 compared to $5 million for the same period in 2021. We had 0 revenue for the first quarter of 2022 compared to $1 million for the same period in 2021. Our revenue in 2021 was derived from a research collaboration agreement with Allergan, now a subsidiary of AbbVie, which came to its contractual conclusion in February 2021.
Finally, our net loss for the first quarter of this year was $19.8 million compared to a net loss of $14.2 million for the same period in 2021.
I'll now turn the call back over to Andy.
Thanks, Ashish. As you can see, despite our disappointment with the DPN results, we've also made great progress across our clinical pipeline. We have a balance sheet that can support a steady stream of upcoming data readouts and a committed team with a strong track record of executing even in a challenging external environment. We remain optimistic and excited about the potential of our pipeline as we approach the second half of 2022 and our next readout in fibromyalgia in July or August.
We will be happy to begin taking your questions now.
[Operator Instructions] The first question is from the line of Ritu Baral with Cowen.
A question on the readout for 2925, the fibromyalgia agents coming up. You mentioned that you are first looking at the NRS and you're also looking at activities of daily living -- I'm sorry, daily function as well as fatigue and sleep. Is there any scientific rationale for a potential larger separation on fatigue and sleep given the mechanism versus centralized pain? And if so, has there been any discussion or any language within guidance, that, that could present a separate alternate path to approval versus pain?
Yes. Thanks, Ritu. So in terms of they're potentially being the ability to generate a larger delta, I think there's a mechanistic rationale, I think, for the molecule being able to improve more symptoms than just pain. I think that's obviously why we're interested in measuring them. I don't think there's enough data to say that there's a reason to believe they should be larger, but I think there is certainly -- we certainly have an interest in measuring them and believe that there could be potential there.
The second part of your question is a little bit unknown. The approved agents for fibromyalgia have all been approved on the basis of patient reported pain endpoints, but there is some precedence for the fibromyalgia impact questionnaire being included in the label of approved products, that's really all we know. So we haven't had a discussion with FDA about that. And so I think that remains TBD. I think our perspective is based on our conversations with clinicians, that there is more to fibromyalgia and pain and some of these other symptoms, in particular, fatigue and sleep can be very bothersome to patients.
And so we would hope that any benefit that patients got from the drug during the study could be reflected or could be captured as part of a pathway to approval. But I think our base assumption right now is that pain is our primary endpoint and pain is the prior precedented pathway to approval.
And any comments just on general conduct any loss -- I'm sorry, dropouts or data integrity issues due to the latest wave of COVID in that study?
I think it's tracking in a similar way operationally to the way that the DPN study did in that we didn't see in that study any operational issues. And I think so far in fibromyalgia, most of the study parameters have been tracking in line with our expectations.
The next question is from the line of Charles Duncan with Cantor Fitzgerald.
Andy and Ashish. I actually had a couple of questions following up on some that Ritu were -- was working on. And that is, I guess, I want to follow up on 2925 and ask you about the fibromyalgia conduct, the study of that or the conduct of that study. I guess I'm wondering if there's anything that gives you confidence in terms of how that study is going in terms of dropouts or anything else?
And then secondarily, with regard to fatigue and sleep, are you tracking on a blinded basis, kind of the feedback from patients as they report some of the -- I guess, some of the information and how they feel while on the drug over the course of the 12 weeks?
Yes. Thanks, Charles. Yes. I think -- so my comments at a high level on the fibromyalgia study is the yes. I think we feel good in terms of what we see operationally that everything looks to be on track.
I just want to -- we do have Kathryn King on the line who, as you know, is our SVP of Clinical and CMC operations. Kathryn, I just want to give you a chance to see if you have any more comments on just on the study conduct.
Yes, I agree with you, Andy. I think we're seeing quality data that we review on a blinded -- in a blinded way. We're having good conversations with our sites about protocol adherence. And I think that in general, we're proceeding, as you said, in the way that we would have expected.
Great. And then with respect to -- sorry, go ahead, Charles.
No, please. I was listening to you.
So I think with respect to the second question, just to clarify what you're asking -- are you asking -- so I think we don't have in a format that I think we would be able to make a meaningful comment on any feedback or data in a blinded sense from the study so far on fatigue and sleep. But just to clarify what you meant, we are obviously collecting endpoints that measure those. And in addition, obviously, measures of global improvement as well over the course of the study. So I think once we do have the data unwinded, we will be able to get a fairly clear picture over which symptoms improved over time and the relative improvements of one symptom versus another.
And then if I can ask a follow-up for you to compare and contrast peripheral pain versus centralized pain. I guess I'm wondering if pain proceeds, fatigue and sleep challenges or fatigue and sleep challenges proceed pain, i.e., would you expect an improvement in fatigue and sleep in a shorter period of time. And when you report out that data, will you be prepared to be able to demonstrate data ,not only pain data but fatigue and sleep data ,over on a weekly basis over the course of the study?
So I'll answer the second part, and then I may have -- we also have Harald Murck on the line, who's our VP of Medical and Clinical Affairs. So I might have to speak to the relative time scale the pain and fatigue and sleep symptoms. I think our endpoints are measured at slightly different time points because as you probably recall, the patient-reported pain is captured on a handheld device that the patient has with them at home every day of the study, so we can analyze data from every day, every week. So that's a more continuous basis. Most of the other non patient-reported pain endpoints are captured at study visits, which are most commonly going to be monthly data points.
So there will be a little bit of a time course but not as granular. But Harald, do you want to comment on the symptoms themselves, the time course. A lot is not known about fibromyalgia, but your comment on that.
I mean, what we know is that a similar brain regions involved in the perception of pain and sleep regulation. And there is quite a bit of interaction. I mean, sleep deprivation needs to change in paying a threshold on the other hand you of course, we have sleep disturbances. But from a clinical perspective, as far as we know from the literature, these things can happen one or the other way. Pain can start or be more prominent or fatigue can be more prominent.
I think it's not that clear if there is a specific sequence, it would identify, let's say, a subset of patients. We have to look at our data and find out.
Okay. I'll look forward to the data and talking about it some more.
The next question is from the line of Joon Lee with Truist Securities.
This is Austin on for Joon. I guess sort of just continuing on 2925, do you think that people being outside more nowadays just walking more given the more lax, COVID restrictions might have reduced the separation from placebo on the NRS scale in your DPN study?
So interesting question. I think the enrollment period for the study for the most part, run from around Q4 of 2020 through to basically Q1 of 2022, if you take the whole treatment period into account. So it's quite a long time period. And there were different ebbs and flows in probably behavior and certainly in COVID restrictions and background factors over that time. Those factors are probably a little bit different by geography, depending on where you were in the U.S.
So I think it's in practice, very, very difficult to ascribe such a time period and a geography where there is a lot of inconsistency on those factors. It's probably very difficult to see if any of those really made a difference. I would say I don't think we've heard any clear, consistent feedback about a single trend, and therefore, really not any connection being made between any trends that we're seeing in and the results. So it's just a very hard topic to look at because there's so much variation.
Do you think that's something you might look into for your fibromyalgia study?
Again, I think it would be equally difficult. The treatment or enrollment in treatment period was very similar. It started just a few months later and finished a few months later. So really covered similar, I think, diversity of time periods and geographies and so forth. So it's probably quite difficult.
I don't know if Kathryn or Harald, do you have any thoughts on whether that's even a possible analysis, but I think it would be quite challenging.
I think in addition to what Andy just -- in addition to what Andy described, I think the use of exercise is the therapeutic modality for fibromyalgia patients also varies widely. Some of those patients will have come in on a pretty prescriptive exercise program and some will have not. So their baseline condition with respect to activity would also be something that would have to be factored into an analysis like that. But I think in terms of the COVID impact on their activity, again, we're across a very wide range of time and a very wide range of geography here in the U.S. where things were different at different times for different subjects.
Yes. Actually, I just want to make a general point that these variabilities are hopefully taken care by the randomization within these trials are always factors which cannot be very well assigned or I hope the randomization. And we have a number of subjects, which is sufficient for that. We'll take care of that.
All right. Just one more question, if I can ask. Given the negative update on DPN, how does that impact your K2 financing deal?
Yes, Ashish, do you want to cover that?
Sure. Thanks, Andy. Yes, there really is no impact. The tranches that we've drawn down on the start of -- the debt financing, we're drawn down upon initiation in September of last year and more recently in March of this year. Neither of one was dependent, of course, on DPN data, which came thereafter.
Those 2 tranches accounted for $25 million of the $50 million total facility. The remaining $25 million is dependent upon upcoming data readouts and milestones across our pipeline.
The next question is from the line of Myles Minter with William Blair.
Just on the DPN study, did you actually do any analysis on drug exposure levels in those patients to make sure that they achieve optimal exposure? Was there anything that we should know about compliance on this product? And how are you tracking that proactively in the fibromyalgia study? That's my first one.
Okay. Yes. Kathryn, do you want to cover that?
Yes. There wasn't PK measured in the trial analytically. We saw a very high level of compliance with study drug throughout the trial. In fact, the tolerability profile lends itself to adherence to daily dosing in the subjects. So in general, compliance is quite high in the study and wasn't perceived to have impacted our results.
Can you give that compliance number as a percentage?
I don't have that in front of me, I'm sorry.
All good. The next question is just on the 458 and the mild cognitive impairment trial. Just on the potential efficacy signals there. Are you hoping to see stabilization of these patients on the neuropsych index that you're measuring there? Or are you hoping to see improvement over 12 weeks?
Just wondering whether that's long enough and how that specific parameter might change in these patients on placebo versus on drug and what you are looking for there.
Yes. That's a great question, Myles. And actually, quite an important one, I think, for the drug. It's this profile and the study design. So we are expecting to see an improvement in cognition in those patients with the drug.
That's what the mechanistic rationale would suggest, and that's what we saw if you remember, in our preclinical data that's been subsequently published in nonhuman primates in the MPTP model. We saw quite a marked improvement. In fact, I think in all of the cognitive assays that we've run preclinically, we saw an improvement. And so it is a symptomatic improvement mechanism. We do think 12 weeks is long enough to see that.
Although, of course, there can be some practice effects over time with some of these tests. We've taken steps in the study design to try to mitigate those practice effects. So patients have to repeat the test during screening and baseline a number of times so that a lot of the practice effect has occurred by the time they start the study proper and various other things like that. But it is symptomatic improvement hypothesis.
The alternative of, as you mentioned, just sort of delaying a decline is typically what we would see with a disease-modifying drug, and that has historically taken often many, many months to show a benefit because -- so you're essentially it's the rate at which the placebo group declines, that is determining the ability to separate. So that's not our hypothesis. And as a result, we do think that 12 weeks is an adequate time to find a signal here.
The next question is from the line of Gary Nachman with BMO Capital Markets.
This is Anton on for Gary. So my first question on 2925, are there any key learnings from the chronic pain study that you can help modify for the fibromyalgia study? And secondly, can you just talk about the protocols that are in place to help mitigate a potential high placebo rate in that study? I have a follow-up after this as well.
Yes, that's great. Let me quickly cover the first point and then maybe Kathryn can weigh in on the placebo part of the question where there are a number of measures that are in place.
The overall learnings that could be applied -- so in terms of the study, of course, the fibromyalgia study is really the last few patients are working their way through the treatment periods right now. So there's no ability to modify the study nor I think did we really see anything that gave us a clear -- it would have given us a clear basis to make a modification even if there was time. So I don't think that's a concern we have. The only thing that we could theoretically have done is to make modifications to the analysis plan. But actually, I think, again, I don't think we saw anything that gave us a clear basis to do that.
And in addition, as I pointed out in the remarks earlier, the underlying biology is very different between the 2 disorders and the presentation and the patients are very different as well. And so actually, quite a lot of what we're analyzing in fibromyalgia, what follows in kind of similar principles is a little bit different to the endpoints that were in the DPN study. So I think if we have seen anything that was a clear lesson learned, the place we could have applied it was the analysis plan. But in practice, we didn't and I think we're quite comfortable with that, both the study design and the statistic analysis plan we have for fibromyalgia are both appropriate. Kathryn, do you want to cover the placebo point?
Sure. So we provided training to our sites at our investigator meeting and at study start-up meetings to really establish what is a research alliance with patients as opposed to a therapeutic alliance where patients are expecting to get better. We also provided training on an ongoing basis throughout the trial for all patients on placebo response reduction that is reminding them that they are part of a clinical trial, that their data is important to us in evaluating these compounds and that it is possible that they are on placebo. Those reminders have proven effective in, let me call it, managing placebo response in CNS trials.
In addition, we provided training for accurate pain reporting, reminding patients how the scale of the NRS works reminding them what each of the measurements that they are reporting mean. So average pain, worst pain, pain on walking. And again, we used that to ensure that we were getting accurate pain responses from patients throughout the trial that was done for DPM and very similarly done for fibromyalgia trial as well.
Got it. And for a follow-up. For 783 in PTSD, are there any modifications to the 50 mg study following the pause of the 150 mg study? Why not just include 150 mg in the -- in that study and increase the number of patients enrolled?
Yes. So no, there aren't modifications to the 50-milligram study as a result of the 150-milligram study being temporarily paused. I think changing fundamentally the approach to a 3-arm study would introduce quite a number of issues. Since part of our motivation was to preserve our -- or to extend our cash runway if we were to change the design of the study to incorporate 2 doses and still allow it to be within our cash runway, the only way we could accomplish that would be to reduce the number of patients per arm. And in addition, there are actually quite a lot of significant operational and logistical complexities to changing those things in study that would probably have meant it would take a little while to go live anyway.
And as I mentioned in the remarks, our goal is still to restart the other study as soon as it's financially and operationally feasible to do so. So I think in thinking it through, our feeling was that the best approach in multiple scenarios is to do it this way to keep the 50-milligram study going as it is. Simply pause the 150-milligram study and then resume it when we're able to probably is the best way to balance our objectives there.
The next question is from the line of Ram Selvaraju with H.C. Wainwright.
This is [Indiscernible] for Ram. Hello, Andy and the team. So with respect to the 2925 program, given the DPN readout, has this opened up additional resources for fibromyalgia component in terms of study site capacity, equipment, personnel, et cetera?
So the fibromyalgia study was so far along by the time we got that data that there wasn't really any need for that. It has fully enrolled in February. And so the last round of patients is making their way through the study right now. And that number, of course, is declining over time down to whenever the last patient last visit is that will be in a little while. So there was really no need to do that.
So the fibromyalgia study is in good shape and additional resources weren't necessary.
And then in terms of the DPN readout, you now have a more focused understanding that the drug is centrally acting and not best to chronic pain conditions with a large peripheral input. Have you thought about other chronic payment conditions you could target with a large brain level processing component? For example, central pain syndrome, which is a rare disease for CNS sensory pathways.
Yes, that's a great question. I think that's exactly right. So we previously had a perspective that there were a range of different follow-on indications. And I think we said we pointed to the general space and kind of said the particular follow-on indications that make the most sense would depend on the data that we got from these 2 Phase IIb studies. So I think, yes, pending the fibro data in July, August, if that study is positive, I think that would certainly open the door to some follow-on indications.
It would be a different group of follow-on indications than if the DPN study had been positive, but there still is further opportunity. So we definitely would be obviously committed to and interested in figuring out exactly what those indications are and what priority order and how we'd pursue them, but that's definitely still part of our plan.
Okay. Great. And just finally, are you able to give us an indication of the percent completion of getting sites up and running for the 783, 50-milligram study.
I think what I would say is that it is basically close to being complete. So I think, as I mentioned, there are still some sites that were planning to take part in the 150-milligram study that are being moved over to the 50-milligram study. But I think whereas on the last call, I think we commented that it had been a little slower than we had -- and I mentioned again today. It has been a little slower than we've been expecting in terms of getting sites up and running. I think we're certainly turning the corner from that now.
And I think once these sites have moved over, we will have the sites that we need. And we already have a majority of the sites up and running. And I think that with this, we will -- we'll be in pretty good shape.
The next question is a follow-up from Myles Minter with William Blair.
Just a follow-up on the SAP for the fibromyalgia study. How exactly is that prespecified here? Do you go in terms of the hierarchical order? Do you go placebo versus 100 milligrams for the NRS scores and step through some secondary outcomes before you go to placebo versus 50? Or do you go for an individual endpoint and go placebo versus 100 and then placebo versus 50?
I just ask because for the fibromyalgia impact questionnaire that might be included in the label, if this thing is positive. I just want to know how far down the pecking order that is in terms of what we can expect for the statistical test.
Yes. Thanks, Myles. That's a good question. So just to be clear, if you recall, our prior fibromyalgia study was an imaging study involving 23 subjects. And it was very informative from a biological perspective and a clinical point of view, but it didn't give us a basis to do a complete dose-ranging look, and it also didn't really give us a basis to estimate with precision the likely effect size from any of these endpoints.
So this is going to be a little bit more of a -- from a SAP perspective. A little bit more of an exploratory type analysis. So we would look at the 2 different doses in nonhierarchical way and we wouldn't have a rigid hierarchical step through the different primary to secondary endpoints. We made that decision basically because we felt it was just -- made more sense because we didn't have enough of a basis to design the hierarchy.
I think in addition, we always said, although the study is designed, following some of the guidance for what a pivotal study needs to look like, but it was not our base plan for this study to necessarily have to be a pivotal study. So I think with all of that, we felt as though a more exploratory analysis makes more sense based on what we currently know.
Okay. That makes sense. So like if you see a signal here, the -- it may be a pivotal study based on some additional commentary with the FDA, but the base case, I guess, would be select the best dose to move forward and go and run 2 identical placebo-controlled trials, 1:1 randomization with that concentration drives...
That -- that's exactly -- that's exactly right.
Yes, that's exactly right. It's not out of the question. I think the way we've been thinking about it. It's not out of the question that this study could in the right circumstances, potentially be pivotal, but it's not the base plan. And you're right, it would be it would be really used to inform the design.
And even if it were a pivotal study, we'd still need to do at least one more, it would serve as a basis for designing that study as you pointed out.
Yes. Thanks for the follow up.
Thank you. I'm showing no further questions at this time. I would like to turn the call back over to Andy for any closing comments.
Thank you very much. Thank you for joining us. We look forward to providing you with our next updates in the future, and I hope that you all have a great rest of the day.
Thank you for joining us today. You may now disconnect.