Good morning everyone. My name is Shelby and I will be your conference operator today. At this time, I would like to welcome everyone to Harmony Biosciences' First Quarter 2023 Financial Results Conference Call. All participant lines have been placed on mute to prevent any background noise. After the speakers' remarks, there will be a question-and-answer session. [Operator Instructions] Please be advised that today's conference may be recorded. [Operator Instructions] I will now turn the call over to Luis Sanay, Head of Investor Relations. Please go ahead.

Thank you, operator. Good morning everyone and thank you for joining us today, as we review Harmony Biosciences’ first quarter 2023 financial results and provide a business update. Before we start, I encourage everyone to go to the Investors section of our website to find the materials that accompany our discussion today, including a reconciliation of our GAAP to non-GAAP financial measures. At this stage of our lifecycle, we believe non-GAAP financial results better represent the underlying business performance. Our speakers on today's call are; Dr. Jeffrey Dayno, President and CEO; Jeffrey Dierks, Chief Commercial Officer; and Sandip Kapadia, Chief Financial Officer. Moving on to slide two. As a reminder, we will be making forward-looking statements today, which are based on our current expectations and beliefs. These statements are subject to certain risks and uncertainties. Our actual results may differ materially and we undertake no obligation to update these statements even if circumstances change. We encourage you to consult the risk factors referenced in our SEC filings for additional details. I would now like to turn the call over to Dr. Jeffrey Dayno. Jeff?

Thank you, Luis and thank you everyone for joining our conference call today. I would like to begin this call by expressing my appreciation to the Harmony Board of Directors for their confidence in me and my ability to lead the company forward in this next phase of Harmony's growth story. For this next phase, I will be joined by my colleagues on the management team, a very talented group of experienced pharma executives who share a common goal and whom I have worked alongside to build this company. I also want to acknowledge and thank the incredibly talented group of people who make up Harmony Biosciences and have generated the strong performance we have demonstrated to-date. As they often hear me say, it takes a total team effort, which is how we work at Harmony. After 12 years as a practicing neurologist, taking care of patients, followed by 25 years in the industry touching every aspect of the business, I have seen the impact that developing and delivering innovative treatments can have on patients and their families. I was eager to join Harmony at the very beginning of the company's journey and I am energized by the progress we have made to-date. In fact, we are pleased to report another quarter of strong performance and operational excellence across our business. We saw continued momentum in our commercial business for WAKIX as well as an advancement of our clinical development programs for pitolisant. Our strong commercial performance since the launch is a result of the unique and meaningfully differentiated product profile of WAKIX and the proven excellence of our commercial organization. This quarter, we achieved another major milestone surpassing $1 billion in cumulative net revenues for WAKIX within the first three and a half years since launch, one of the…

Thanks Jeff. Q1 represented another strong quarter of performance with demonstrated growth and momentum in our underlying business fundamentals. Net sales for the first quarter of 2023 were $119.1 million, which represents a 40% growth from the same quarter prior year. We also surpassed $1 billion in cumulative net sales in the first quarter, a significant milestone achieved in less than three and a half years from our launch, demonstrating value creation for the organization and a reflection of the impact that we've had on adult patients living with narcolepsy. I'd like to highlight a few of our underlying business fundamentals on slide five that drove our performance in the first quarter. The average number of patients on WAKIX in the first quarter increased to approximately 5,100. The average number of patients on WAKIX grew approximately 1,200 patients in the last four quarters, demonstrating strong consistent growth in our patient base over the last year. The growth speaks to the strong interest in WAKIX we're seeing in the narcolepsy community. Growth in new patient starts, growth in new prescribers, along with solid patient refill behavior following the seasonal payer dynamics of prescription reauthorizations early in the first quarter. We exited Q1 with approximately 5,200 patients on WAKIX with strong momentum coming out of the first quarter. In March, we saw the highest month of topline prescription demand for WAKIX in over three years and the strongest month of new patient starts in a year. The performance coming out of Q1 reinforces our confidence in WAKIX and the long term growth opportunity in adult narcolepsy. The growth in patients on WAKIX continues to be driven by a broadening and strengthening of our prescriber base. We continue to see growth in new of WAKIX in the first quarter and now with more…

Thank you, Jeff. Before I begin the clinical update, I would like to take a moment to announce the appointment of Dr. Kumar Budur as Harmony's new Chief Medical Officer. Kumar joined us last March as the Senior Vice President and Head of Clinical Development and quickly stepped in and established operational excellence, while building out the clinical team. His impact has been demonstrated by the efficient completion and topline data readout of our PWS Phase II trial in the second half of last year and the strong momentum he has been leading in our Phase III registrational trial in idiopathic hypersomnia. Prior to joining Harmony, Kumar spent six years at AbbVie, and before that, six years at Takeda. A nationally recognized expert in research and development, he has overseen programs ranging from late discovery, early clinical development to late clinical development, and post-marketing studies. Kumar was involved in four new drug applications and was the lead for the clinical trial submission and approval processes for two of these NDAs. He was trained Cambridge University in the UK and Cleveland Clinic in the US and completed his Residency in Psychiatry with Fellowships in Neurophysiology and Sleep Medicine. Kumar is board-certified in psychiatry and sleep medicine and holds a Master's Degree in Clinical Research from Case Western Reserve University. He brings 13 years of experience in drug development in the pharmaceutical industry along with a keen strategic eye and a steady hand in managing development portfolios. I am very pleased to welcome Kumar as a member of our management team. Moving to our development pipeline, to expand the clinical utility of pitolisant toward potential new indications, in additional patient populations living with rare neurological diseases as shown on slide six. Starting with our development program in idiopathic hypersomnia or IH, which…

Thank you, Jeff and good morning everyone. This morning, we issued our first quarter press release and filed our 10-Q, where you'll find the details of our financial and operating results. Our financial performance is also shown on slides seven, eight, and nine. We're pleased to report a great start to the year with growth across several of our key metrics, including strong revenue growth, improved profitability, and continued cash generation. Our performance gives us the continued confidence for the remainder of the year as we remain well-positioned to execute on our growth strategy. So, let me take a moment to take you through the details of our results. For the first quarter 2023, we reported net revenues of $119.1 million compared to $85.3 million in the prior year quarter, representing a growth of 40%. Our performance reflects the strong underlying demand for WAKIX. We also successfully navigated the typical Q1 headwinds from seasonal payer dynamics and their normalization of trade inventories during the quarter. In the first quarter of 2023, operating expenses were $57.9 million compared to $43 million in the prior year quarter. The higher operating expenses were primarily driven by our ongoing commercialization of WAKIX and the advancement of our clinical development program. Operating income improved with first quarter 2023 operating income of $40.4 million compared to $26.6 million in the prior year quarter, representing an increase of 47%. Non-GAAP adjusted net income for the first quarter of 2023 was $40.1 million or $0.66 per diluted share compared to $31.1 million or $0.51 dollars per diluted share in the prior year quarter, reflecting strong revenue growth and prudent expense management. We believe non-GAAP adjusted net income better reflect the underlying business performance. Please see our press release for a reconciliation of GAAP to non-GAAP results. During the first quarter of 2023, we generated approximately $43 million of cash from operations and ended the quarter with $392.4 million of cash, cash equivalents, and investment securities. For the remainder of 2023, we expect continued growth quarter-over-quarter in revenue and average number of patients on WAKIX. We also expect to continue to invest in R&D and SG&A as we advance our clinical development program and support the commercialization of WAKIX. Overall, we're confident in WAKIX being a potential $1 billion-plus narcolepsy opportunity with the potential to contribute up to an additional $1 billion, if approved, in IH and other lifecycle management programs. In conclusion, we're pleased with the strong financial performance, which continues to strengthen our company profile and enable us to execute on our growth strategy. And with that, I'd like to turn the call back to Jeff for his closing remarks. Jeff?

Thank you, Sandip. In summary, as we turn the page on a new chapter at Harmony, we will not rest on our past success. We will remain focused on helping even more adult patients living with narcolepsy with WAKIX, completing our Phase III registrational trial in idiopathic hypersomnia, advancing our clinical development program in Prader-Willi Syndrome, working with our partner Bioprojet on new formulations to extend the pitolisant franchise to help even more patients living with rare neurological diseases, and continuing our relentless pursuit of new assets to build out our pipeline. This concludes our planned remarks for today. Thank you for joining our call and I will now turn the call back over to the to facilitate the Q&A session. Operator, can you please open the call to questions?

Thank you. [Operator Instructions] We'll take our first question from Charles Duncan with Cantor Fitzgerald.

Hey, good morning and congratulations, Jeff, on the appointment to CEO. Thanks for taking our question. Sure. So, I had a commercial question and a pipeline question. I guess you did a great job addressing the commercial dynamics, but it seems like exit number of patients, new patients were notable in the first quarter. I guess I'm wondering how do you see that business ramping now about halfway through the second quarter? And then the second question is related to the pipeline, I'll wait for that.

Okay, Charles. Good morning. Thank you. I'll let Jeff Dierks answer the first question about exiting numbers.

Sure. Good morning Charles. Thanks for the question. So, clearly, we're extremely pleased with our continued growth in both the average number of patients as well as the strong patient count ending the first quarter. We did share in our prepared remarks, obviously, we saw a very strong month of March, the highest month of topline for and demand for WAKIX we've seen in over three years and a strong month of new patient starts in over a year. And although we're not providing any forward looking guidance, Charles, what I can tell you is that momentum that we saw in March, we're seeing that continue in April. And we're very pleased with the performance that we're seeing heading into Q2. So, hopefully that gives you a little perspective in terms of what we're seeing heading into the second quarter and how to think about the remainder of the year.

Just as a follow-up to that, how is persistence tracking? You may not actual -- have the actual data, but how do you feel about patients staying on drug?

Sure, Charles. So, when you take a macro view of sort of looking at the narcolepsy category, this is a lifelong non-curative type of disorder and patients continually churn through medicines. So, if you look overall in the category, on average patients stay on the product between six and 10 months and what we're seeing with the WAKIX is WAKIX is on the higher end closer to 10 months. Extremely pleased with the feedback that we're getting from healthcare professionals and patients and we're really excited about our ability to continue to grow our patient population.

Okay. Super. Quick question, pipeline idiopathic hypersomnia, need to see the enrollment pace picking up or pickup and ahead of schedule. But question that I have is regarding patient heterogeneity, I guess how do you how do you maintain control over call it the quality of patient enrolled and therefore the risk of the trial while also seeing an acceleration in demand. Is that something you're tracking?

So, Charles, I think that in terms of the acceleration in the study I think is a result of the high level of interest from both a patient and non-HCP community in terms of the Phase III IH INTUNE trial. The patients obviously come in, have a diagnosis of idiopathic hypersomnia. They have a requisite sort of level baseline of excessive daytime sleepiness. So, no concerns about in terms of the patient population being enrolled in the trial. And what we're seeing I think just for flex, the high level of interest given the mechanism of action of pitolisant for this condition. So, we continue to be excited for the opportunity. As you know, tracking about six months ahead of plan and we're on track to complete enrollment in the second quarter. And then I think if successful, we look at this opportunity as a potential next new indication for WAKIX with about 40,000 patients diagnosed with IH. So, that's in terms of what we're looking at in this trial.

Great. Looking forward to a lot of data later on this year. Thanks for taking the questions.

Sure. Thanks, Charles.

And we'll take our next question from Francois Brisebois with Oppenheimer.

Hi. Thanks for taking the questions and congrats on a great quarter here. In terms of the growth here, you talked about the exit number. Remember last year in the first quarters that normal seasonality, the growth to net that happens in the first quarter. But there seemed to be some additional maybe COVID-related one-offs. Can you just help us maybe understand why that didn't happen this year? Why you had a strong first quarter despite the seasonality? And maybe also compare and contrast the average number to the exit number that you saw in the first quarter, just so we can maybe get a read-through of things to come?

Yes. Sure, Frank. Good morning. And yes Jeff Dierks can respond to that.

Sure. Good morning Frank. Yes, so with respect to last Q1 in 2022, we did talk about having two one-time events that did not occur and we don't anticipate occurring moving forward. So, one related to changes in the business rules around our patient assistance program. The second related to Foundation Support Medicare patients. So, we obviously had no additional changes to the business rules in our path this year. We didn't see any disruption in terms of foundation support for Medicare patients. So, that helps to explain a little bit of the dynamics, but think more importantly, we continue to see strong growth within our business. WAKIX is very much a growth story. We continue to see very strong topline prescription demand. We have the normal reauthorization of prescriptions in January into early February, but coming out of the quarter, the exiting number of approximately 5,200 really speaks to the strength that we see in the momentum coming out of Q1 and we're really excited about what we're anticipating for the remainder of the year and beyond.

Great. And then you mentioned how strong March was in a record-setting for new patients. And I'm just wondering, three and a half years into launch, is there one thing in particular that comes up as to why all of a sudden there's still some kind of this much kind of growth?

Sure. Well, there's a couple of reasons, one, I would say first thing Frank is obviously, our expanded field sales team has now had a year in their geographies. So, our ability to extend our reach and our frequency to healthcare professionals and educate prescribers, I think, continues to drive both the breadth and the depth of our prescriber base. But the other thing I shared in my prepared remarks is we've compared our launch very favorably to oxybate. And so you look at that product, I mean certainly very successful product in the market, helped a lot of patients and we continue to watch that product grow over its lifecycle. And that gives us a lot confidence in our growth potential, right, because we have the ability to access most of the oxybate prescribing healthcare professionals, the non-oxybate prescribing healthcare professionals that tap into that approximately 9,000 narcolepsy treating healthcare professionals. But then the other component that I shared in my remarks too, Frank, is we've just conducted some market research and it's very consistent with what we heard last year. It was done in February with approximately 70 healthcare professionals and we continue to see those healthcare professionals with WAKIX experience 95% of them. It's shared that they're going to write the same or increase prescribing and even more importantly, 50% of the doctors with zero experience with WAKIX stated their intent to prescribe in the next six months. So, we continue to see growth in the depth of breath of our prescriber base. I think it speaks to the meaningfully differentiated product profile and we're looking forward to growth for years to come with WAKIX and adult narcolepsy.

And I think what I would add to that, Frank, I think one of the drivers terms of the market research, Jeff, was the non-scheduled status as an important component in terms of the product profile driving some of that interest in continued prescribing.

Okay, great. And then just -- I'll sneak in a quick last one here. Can you ballpark maybe the percentage has a change of patients on both oxybates and WAKIX? And any update on maybe how reimbursement works for those patients? Thank you.

So, Frank, it's been relatively consistent. It's been low double-digit percentage of WAKIX patients are also on an oxybate. And what we've seen within the reimbursement landscape is there really hasn't been any changes over the last few quarters. Again, this is a rare orphan population. So, it's a small percentage of patients that are spread over about 125 different payers. So, when you're looking at a category when patients are seeing benefit on both products, it is being reimbursed very successfully and we're really pleased with our continued growth and uptake.

Great. Thank you.

And we'll take our next question from David Amsellem with Piper Sandler.

Hey, thanks. So, just a couple. First, can you talk about the attrition rate associated with WAKIX? And is it fair to say that it that a potentially lower rate of attrition could be driving that number in terms of average patients on a drug? So, that's number one. Number two, can you talk about the cadence of gross to net as the year progresses, particularly with the oxybate commercial dynamics being fluid? So, that's the second question. Third, just philosophically, what's your view on share buybacks, just given where the stock is? Thank you.

Sure, David. Good morning, David. Okay, Jeff, you want to speak to the attrition and then kind of gross to nets and Sandip can discuss philosophy on share buyback.

Sure. Thanks for the question, David. So, from an attrition rate, looking at in terms of just discontinuation rate, I mean, we've shared that looking across the category to macro level at about 12 months within the first year, you see about 30% to 50% of all narcolepsy patients discontinuing medicines. And we've shared that WAKIX patient medication behavior falls right in the middle of that range and it's very consistent with what we're seeing for every other product. So, I think our continued growth in the average number of patients speaks to our ability to continue to drive topline demand, adding new patient starts, and our DC rate does compare favorably to the other products in that category. So, hopefully that helps provide a little bit of insight in terms of patient medication dynamics. And then maybe I'll turn it over to Sandip to talk about gross to net in some of the cadence.

Yes, no, thanks Jeff. With respect to gross to net, I think we're seeing basically the same dynamic we see across the industry, same dynamic. We see the growth in that tends to be higher in the first quarter or as we have higher obligations for certain deductions, but generally normalizes in the second quarter and beyond. So, nothing different from what we've seen in the past and nothing different from what other companies would experience in early a specialty in this space. And I think, yes, a very important question clearly around the potential to share buyback. Look we're always evaluating options to maximize shareholder value, including business development or a divestment maybe return of capital to shareholders. So, that's something that certainly has a company we'd evaluate. And as you know, we're in a very unique position as a company. We have a strong balance sheet of $392 million of cash and cash equivalents on the balance sheet. We're generating positive cash flow as you saw in the last quarter. Again, another quarter of strong cash generation and we're a profitable company. So, we have flexibility to execute on multiple of these fronts and certainly something that we're going to continue to evaluate.

Okay. Helpful. Thank you.

Thanks, David.

And we'll take our next question from Graig Suvannavejh with Mizuho Securities.

Hey, thanks so much. First of all, congrats, Jeff, again, on being named permanent CEO, and my best on great success. My first question, it might be an obvious answer, but I figured I'd ask the question anyway. But now that you are permanent CEO, is there any change in Harmony's corporate goals and perhaps any change to the near term or longer-term corporate strategy. So that's my first question. I'll wait for that before I ask my second question. Thanks.

Yes, sure, Graig. Yes, thanks to your comments. With regards to our strategy and with regards to my new role, our strategy and focus for the company remains the same. And I was an integral member of the team who designed our growth strategy along with many folks around the table here. So as I mentioned, we'll continue to focus on obviously growing our core business and helping even more patients with narcolepsy with WAKIX. And then advancing our clinical development programs, which is a key focus, mainly our most advanced program in idiopathic hypersomnia, looking forward to our engagement with FDA on the Prader-Willi program and obviously the readout in Type 1 myotonic dystrophy in the fourth quarter this year. We are also focused on working on new formulations of pitolisant with our partner, Bioprojet, with the goal to extend the pitolisant franchise out beyond 2040. In addition, obviously, sort of the last pillar of our growth strategy looking at new assets to build out our pipeline an important priority for us and with a lot of focus on that as well. So I think in summary, our strategy remains the same and Harmony remains a growth story. And I think given the focus of our growth to advance our lifecycle management programs, build out our pipeline develop new formulations of the pitolisant. I think I'm well positioned to lead Harmony forward in our next phase of growth.

Great. Thanks so much for that. And just maybe follow-up questions just more on the commercial side of the business. My just in terms of the ability to commercialize WAKIX, just wondering if at this stage in time given what you're seeing out with the sales force, are you basically at 100% back to where you were pre-COVID. Just want to know kind of where you're able to engage and whether there's still opportunities to engage even better. And then beyond that, you were able to add about 1,200 patients over the last several quarters? And I'm wondering if that's a good run rate for the company on a go forward basis or not?

Jeff Dierks.

Sure. So Graig with respect to commercialization of WAKIX and sort of are we? So when you look at in-person engagement with our field sales team, we're at about 85% or so of all of our engagements being front and center in front of a healthcare professional and his or her office staff. And I think that that's probably going to be sort of the new normal, I think a lot of offices have adopted telemedicine as a standard practice, especially for managing individuals that are sort of well controlled on chronic conditions. And so what we've done as a result of that is really looked at our ability to evolve our commercial model to supplement our in-person engagement with our field team. So we do have a six person virtual remote territory management team that ends up supporting outbound contacts with healthcare professionals in some white space areas. Making territory manager as well as supporting any request for healthcare professional rep contacts on our branded website. We obviously have implemented a field reimbursement manager team, which is a very standard place across this group. I know that Jazz and Avadel, certainly have a team for their perspective organizations in terms of providing subject matter expertise for reimbursement and access for WAKIX. And we have a great organization here. We have an outstanding home office team that continues to utilize data and insights to really drive informed business decision making towards our business across the adult narcolepsy journey. So I think we are very pleased with our evolved commercial model. Our main goal is to make sure that we're meeting the needs of our customers and adding value. And I think that we're at -- operating at a very high impact level with our field teams, with our remote territory…

And Graig, the way we sort of summarize with that concept is, WAKIX provide broad clinical utility just from a sort of kind of a medical clinical perspective reflective of that larger sort of HCP universe, which is based on the overall benefit risk profile.

Thanks again.

Yes. Thank you, Graig.

And we'll take our next question from Ami Fadia with Needham.

Hi, good morning. Thank you for taking my question. Firstly, Jeff, congratulations on your being announced as the permanent CEO. I have two questions.

Thank you Ami.

I have two questions. So okay. Can you talk about how the number of healthcare professionals that are prescribing WAKIX has evolved over the last year or so? And where are the incremental subscribers coming from? Are they ones that are enrolled in the oxybate REMS program or out of the group that? And then also if you can talk about the number of patients being prescribed, WAKIX per physician, how that has evolved? Thank you. And I have one more.

Okay. All right. Ami, I'll turn it over Jeff Dierks, but I think that in terms of the physicians how that's evolved over time is a really interesting story based on some commercial analytics that the team has done that Jeff starts to speak to.

Sure. So I mean in terms of the evolution of our number of unique prescribers of WAKIX, what we've seen is a very consistent growth in the number of new prescribers even going all the way back through COVID. And I think it speaks to our ability to tap into 9,000 eligible narcolepsy treating healthcare professionals. So our rate of new adds has been, as I said, very consistent every single quarter that we've had since COVID and they're coming from the to be REMS enrolled healthcare professionals, but certainly we have a very, very high number of prescribers within that universe. Those care professionals tend to be more comfortable in diagnosing and treating narcolepsy. So we've penetrated that audience very deeply, but where we're really seeing continued growth is in that additional 5,000 healthcare professionals that are not enrolled in the REMS program. We did a lot of analytics that really supported our expansion of our field sales team And there were about 1,000 healthcare professionals that had just only prescribed wake promoting agents really in a refill capacity. And we started to see those healthcare professionals initiating treatment with WAKIX, which speaks to the broad clinical utility that Jeff spoke of earlier. The fact that it's the only non-scheduled treatment option, you can write it with refills healthcare professionals that really aren't comfortable with DEA scheduled medicine. So we're seeing growth more predominant from that 5,000 audience and the 4,000, because we're very penetrated. But the growth that we're seeing in that 4,000 oxybate REMS enrolled doctors is in the depth of their prescribing, right? There's a higher concentration of patients within that audience. So we continue to see those individuals starting new appropriate adult narcolepsy patients on product. And then in terms of the number of patients per healthcare professional and how that evolved, as you would imagine with any type of launch, the number of patients per healthcare professional continues to grow as we get further in. We're very, very pleased with the fact the vast majority of healthcare professionals that start one patient on WAKIX ultimately find a second, a third, a fourth within their practice to start them. Given the rare orphan model, Ami, that evolution, it's not, I start two people in the same month. Most narcolepsy patients see their healthcare professional every three or four months. So the time it takes for somebody to become a repeat prescriber to a trialist to an adopter evolves over time, but we're extremely pleased with what we're seeing in growing not only the breadth of our prescriber base, but also the depth.

Great. That's helpful. Just with regards to business development, I believe you indicated that you're exploring opportunities that could result in a new product launch, both during and after the LOE for WAKIX. Can you talk about kind of the type of assets you're evaluating at the moment and if there were maybe more that versus late stage, any color on that would be helpful?

YES. Sure, Ami. I think, we continue to be active in this space evaluating the BD landscape and potential opportunities. And as I mentioned, it is a strategic priority for us. Obviously, we're in a solid position to execute on business development with our strong cash position, approximately $392 million as of end of March. In terms of it continues to be a target-rich environment, and we're looking at across both early phase and late phase of development to launch both during and beyond the WAKIX life cycle. We want to be strategic in the decision-making so when we announce a deal, it will make sense and be a good fit for Harmony. So we're really looking at a lot of different opportunities across development phases focused on orphan rare neurology, which is sort of the sweet spot, but also looking at adjacencies and other neurologic disorders where we can leverage internal expertise and our infrastructure. Sort of a broad, looking at the landscape broadly, but then honing in and trying to be strategic for what would be a good fit and make sense for Harmony.

Got it. Thank you.

Thanks, Ami.

And we'll take our next question from Corinne Jenkins with Goldman Sachs.

Good morning, everyone. Maybe two for me. First, we talked a bit about the patient growth this quarter. It was about 200, which is a bit shy of your stated quarterly target of an average of 300 patients. So what seasonal dynamics might have been at play here since we didn't have that outflow of patient assistance programs this year?

Good morning, Corinne. Jeff, do you want to answer that?

Sure. Good morning, Corinne. Patient growth in Q1 of adding 200 patients is actually right in line with our expectations. We've not stated moving forward 300 patient ads per quarter. First quarter, as you know, we've got obviously the normal seasonal payer dynamics. You've got reauthorizations of prescriptions. And one of the unique things that we will see as we move further into our launch is, the more number of established patients that we carry over year-over-year, the more patients that are going to be facing these reauthorizations. So if you go back a year, we had approximately 3,800 patients on product, bringing them into the new calendar year. This year, we have 4,900 patients carrying over, so you have another 1,100 patients that are being exposed to the reauthorizations. And a lot of it is about timing, right? So January you get ultimately a lot of individuals that are going through that reauthorization process that usually takes January and early February. And what we're seeing really is a very, very strong dynamic and momentum coming out of Q1, with March really being, as we've talked about, the highest number of top-line prescriptions that we've seen in three years and new patients starts in a year. So we're looking forward for that momentum to carry forward. But I think our ability to grow 200 average patients it's 100% higher than a year ago without the one-time seasonal, sort of the one-time dynamics that we talked about earlier in the call. We're really pleased with what we're seeing, really excited about the future growth potential for the brand and this product becoming a billion dollar plus opportunity.

Okay. And then you mentioned that there was about 5,000 physicians that aren't on REMS but have prescribed WAKIX. I'm curious if you could give us a sense for how many patients on average those physicians are treating that would be candidates for WAKIX?

Sure, so Corinne, there are 5,000 healthcare professionals that are not enrolled in the REMS- oxybate program. It's not that all 5,000 of them have prescribed WAKIX, but that is a very unique opportunity for us to tap into over our life cycle. So we've seen within the 4,000 oxybate REMS program doctors, a large percentage of those individuals have prescribed. You're probably looking at well over 1,000 of those 5,000 health care professionals outside the oxybate program that have prescribed the product, and we continue to see growth at a very regular cadence from that 5,000 group. Clearly, those are individuals that are not a large sleep center. They probably have three to five narcolepsy patients under their care. Some may have as many as five to ten, some may have as few as one to three, but they all represent opportunity. And our expanded field sale team really has been sort of right sized to be able that we can appropriately reach and frequency with these healthcare professionals to educate them. And lastly, in terms of who's an eligible patient for WAKIX, what I would tell you and what we hear from feedback from healthcare professionals is that almost every adult patient living with narcolepsy is an appropriate patient for WAKIX. And we hear that loud and clear from KOLs, just given the overall benefit-risk profile, the meaningfully differentiated product profile, the non-scheduled status. So hopefully that helps a little bit for some color on your response.

YES, that's helpful. Thank you.

YES. And, Corinne, I think, what Jeff mentioned before, in terms of those HEPs that are in the oxybate REMS, they tend to be more experienced, with more patients that they're managing. So it's the depth of prescribing in that group where the opportunity continues. The other 5,000 outside the oxybate REMS, they are probably not managing as many patients. So I think the breadth across that group with regard to the opportunity for continued growth in the brand.

Great. Helpful. Thank you.

Thanks, Corinne.

And we'll take our next question from Jason Gerberry with Bank of America.

Hey, guys. Good morning. Thanks for taking my questions. First one, just ahead of the Phase III IH readout, I'm just curious how you'd frame the bogey for commercial success for WAKIX. Do you need to match the treatment effect size that's I wave saw, which I think was like a six and a half point placebo adjusted ESS Delta, or is something less than that, considering WAKIX other differentiating factors enough? Then my second question is more about just as we see more oxybate competitors trickle into the market this year, how you're thinking about 2024 growth to net and just net pricing dynamics for WAKIX, do you see any impact there at all? Thanks.

YES, sure, Jason. YES, thanks for the questions. So with regards to the IH, I'll let me answer that then pass it over to Jeff Dierks. So with regards to the INTUNE study, I think, what success would look like is, obviously defined by a positive outcome on the primary endpoint around improvement in EDS, as measured by the F-4 sleepiness scale. I mean, as you know, it's a randomized withdrawal design, an enriched design with four weeks of randomized withdrawal phase. So I think in terms of the magnitude with regards to, we know that the data in the narcolepsy trials showed about a five to six point difference from baseline to endpoint in improvement in Epworth. And given that IH is in adjacency to narcolepsy, anticipating, sort of, a similar kind of outcome. In addition, looking at other important endpoints around, sleep inertia and the EDF catheter hypersomnomy severity scale. So I think, we're confident in terms of the mechanism of action and how pitolisant would perform in patients with IH and look forward to top-line data readout in fourth quarter this year.

And then, Jason, to answer your second question about just oxybate competition and sort of how we're thinking about 2024 and even really what we're seeing now is we continue to be extremely pleased with our growth and what we reported in Q1 with respect to net sales and growth. And obviously we've seen strong performance of WAKIX with the availability of other branded oxybates on the market since our launch. And what we've seen with the launch of generic oxybate in January 23rd, we haven't seen any impact on WAKIX. We saw really strong patient growth in Q1. And a lot of that is our belief that WAKIX is growing the brand segment of the narcolepsy market and, more importantly, growing beyond oxybate. As we've talked about this segment of doctors that are oxybate REMS enrolled, but we have this unique opportunity in the 5,000-ish healthcare professionals who are not enrolled in the REMS program that we can tap into that unique diagnosed patient opportunity. Moving forward, we've talked with payers. We've not really seen any major changes with respect to contracting. We don't believe that payers are going to be implementing any types of steps for WAKIX through either branded or generic Oxybate. And we think that we're very well insulated in our ability to continue to grow here even with more oxybates on the market.

Great. Thanks, guys.

Thanks, Jason.

And we'll take our last question from Danielle Brill with Raymond James.

Hi, guys. Thank you for squeezing me in and Jeff, congrats much deserved on the promotion. So I just wanted to clarify a follow-up to a prior question on the expected run rate moving forward. It sounds like moving forward, we should be anticipating around 200 net patient ads per quarter. Is that fair? And then I wanted to ask, so obviously there was unfortunately a citizen's petition filed recently. I'm curious, if this is something that is even on the radar of KOLs and the narcolepsy community, and if so, if this has had any impact or if there's been any feedback from prescribers. YES, I'll stop there. Thank you.

YES. Sure. Good morning, Danielle. Thanks for your question, and I'm happy we could squeeze you in. So let me respond to the question about the citizen's petition first and then Jeff can provide the follow-up question that you had. So while we take the allegations stated in the citizens petition seriously, it is our position that the citizens petition is full of unfounded allegations. And we're confident that a careful review of the unfounded allegations, in light of the data and information available to FDA from a broad range of sources, will ultimately lead the agency to deny the petition on the merits. And with regards to WAKIX, and it received regulatory approvals around the world based on a strong body of scientific evidence, which demonstrated to be safe and effective in patients with narcolepsy. So I think that, with that we remain confident in the overall risk-benefit profile of WAKIX based on the robust clinical development program, post-marketing safety data that we submit on a regular basis, and the FDA reviews on a regular basis. So I'll turn it over to Jeff to clarify the second question.

Sure. And so with respect to run rate, Danielle, I mean, obviously we're not providing any forward-looking guidance, but I think you've been very astute in terms of looking at our business. And there is a rhythm to our business. There is some seasonal, dynamics in Q1 and Q3 that tend to provide some headwinds. Q2 and Q4 tend to provide some tailwinds. So, you're thinking about the business correctly moving forward, but I think we've got really strong momentum going into Q2. We expect that patient ads are going to really probably mirror those dynamics that we see. We know that there's a significant growth opportunity ahead of us. Obviously, looking at oxybate is a great analog in terms of where we are relative to them and their launch and what we see as a future opportunity growth moving forward. So I think you have a very good handle on looking at the business and really being able to tap into that opportunity is really the market allows around the seasonal dynamics.

Operator?

And thank you. I'm showing no further questions. I would now like to turn the call back to management for any closing remarks.

YES. Thank you, operator. And thanks to everyone for joining our call today and for your interest in Harmony. As you heard from the team this morning, our business remains strong and our growth potential is significant. We will continue to focus our efforts on addressing the unmet medical needs of patients living with rare neurological diseases. I am proud of the team. I am excited to lead Harmony forward in our next phase of growth. Thank you and have a great day.

This does conclude today's Harmony Biosciences first quarter 2023 financial results conference call. You may disconnect your line and have a wonderful day.