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DATE

Wednesday, May 6, 2026 at 9 a.m. ET

CALL PARTICIPANTS

  • Chairperson and Chief Executive Officer — Martine Rothblatt
  • President and Chief Operating Officer — Michael Benkowitz
  • Chief Financial Officer and Treasurer — James Edgemond
  • Executive Vice President of Product Development and Xenotransplantation — Leigh Peterson
  • Executive Vice President of Strategic Development — Patrick Poisson
  • Investor Relations — Harrison Silvers

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TAKEAWAYS

  • Total Revenue -- $782 million for the quarter, with noted negative impact from severe winter weather and pharmacy operations issues that slowed patient starts, particularly in February.
  • Tyvaso Revenue -- $458 million for the quarter, with Tyvaso DPI driving 9% year-over-year growth attributed to higher patient demand, despite lagging sales of nebulized Tyvaso.
  • Ralinepag Clinical Results -- Martine Rothblatt stated, "we showed a threefold reduction in disease progression compared to background therapy." in PAH, with ralinepag achieving all primary endpoints and exhibiting better hazard ratios than selexipag over four years.
  • IPF Therapeutic Advancement -- Tyvaso was cited as surpassing existing IPF drugs, with Rothblatt stating it "boosted FVC to over 100 milliliters of oxygen and."
  • Market Expansion Guidance -- United Therapeutics (UTHR +4.45%) expects ralinepag to double its PAH patient base to over 30,000 within two years post-launch, and projects total company revenues surpassing a $4 billion run rate by 2027, potentially doubling with the combined impact of ralinepag and Tyvaso for IPF.
  • RALDPI Development Milestone -- United Therapeutics activated an exclusive option with MannKind for a second DPI, now advancing RALDPI for multiple indications, with management forecasting it as "our biggest product ever" and initial Phase I study targeted for completion before year end.
  • Commercial Execution Metrics -- Tyvaso patient shipments have grown for the last five months; prescriber breadth and depth continue to increase, aided by new higher-dose capsule and combination kit launches.
  • Regulatory Update for Tyvaso in IPF -- A supplemental new drug application is planned by the end of summer, and Benkowitz noted, "If we receive a standard review time line, we would expect to launch by Q2 of next year."
  • Product Launch Readiness -- Sales force investments are being deployed mid-year to support anticipated ralinepag and IPF approvals across PAH, PH-ILD, and IPF markets.
  • Strategic Product Approach -- United Therapeutics is executing a "multiple shots on goal" strategy, simultaneously developing Tyvaso and ralinepag in oral, DPI, and SMI formulations across PAH, IPF, PH-ILD, and PPF indications.

SUMMARY

Management reported the successful completion of two pivotal Phase III trials, with Tyvaso and ralinepag demonstrating superior outcomes in large disease populations and supporting substantial multi-year revenue forecasts. The company detailed ongoing RALDPI development, with a Phase I study commencing and manufacturing ramping up to meet projected high-volume demand across multiple pulmonary indications. Commercial operations are tracking increased patient shipments and prescriber expansion, with new high-dose Tyvaso products supporting growth. Regulatory timelines for Tyvaso in IPF remain on track, as the firm plans to submit for approval by summer’s end. Product development strategies focus on diverse formulations to maximize the addressable market and tailor therapy to patient-specific needs across respiratory diseases.

  • Rothblatt characterized both Tyvaso for IPF and ralinepag for PAH as capable of independently exceeding current total revenues, jointly projecting combined revenues that could "lap our 2027 $4 billion revenue run rate twice over."
  • Clinical trial data for Tyvaso and ralinepag are already prompting both payer and physician engagement, with Benkowitz stating advisory boards report "they're very impressed by the data, very excited about bringing Tyvaso to market." and expect combination therapy paradigms in IPF.
  • Poisson confirmed RALDPI formulation uses MannKind's crystal carrier IP is not a prodrug, and will be available for Phase I assessment by year-end, streamlining future regulatory steps due to its similarity with existing solid-dose ralinepag.
  • The company disclosed that a Phase II clinical trial for treprostinil SMI in PH-COPD is scheduled to follow current healthy volunteer studies, supporting further pipeline breadth.

INDUSTRY GLOSSARY

  • PAH (Pulmonary Arterial Hypertension): A rare, progressive disorder characterized by elevated blood pressure in the arteries of the lungs, leading to heart failure if untreated.
  • IPF (Idiopathic Pulmonary Fibrosis): A chronic, progressive lung disease marked by scarring of lung tissue, resulting in declining lung function and eventual respiratory failure.
  • Tyvaso DPI: A dry powder inhaler formulation of treprostinil designed for the treatment of pulmonary hypertension indications.
  • SMI (Soft Mist Inhaler): A device delivering medication as a fine mist to the lungs, offering an alternative to dry powder or nebulized inhaled delivery.
  • RALDPI: Development code for an inhaled dry powder formulation of ralinepag aimed at multiple indications, including PAH, ILD, IPF, and PPF.
  • PK (Pharmacokinetics): Study of how a drug is absorbed, distributed, metabolized, and eliminated in the body.
  • FVC (Forced Vital Capacity): A measurement of lung function assessing the amount of air exhaled forcefully after a full inhalation, commonly used as an efficacy endpoint in pulmonary trials.
  • CLIMB Digital Lung Model: United Therapeutics’ proprietary computational biology platform for simulation and drug development in pulmonary diseases.

Full Conference Call Transcript

Harrison Silvers: Thank you, JL. Good morning. It is my pleasure to welcome you to the United Therapeutics Corporation First Quarter 2026 Corporate Update Webcast. Remarks today will include forward-looking statements representing our expectations or beliefs regarding future events. These statements involve risks and uncertainties that may cause actual results to differ materially. Our latest SEC filings, including Forms 10-K and 10-Q, contain additional information on these risks and uncertainties. We assume no obligation to update forward-looking statements. Today's remarks may discuss the progress and results of clinical trials or other developments with respect to our products.

These remarks are intended solely to educate investors and are not intended to serve as the basis for medical decision-making or to suggest that any products are safe and effective for any unapproved or investigational uses. Full prescribing information for the products is available on our website. Accompanying me on today's call are Dr. Martine Rothblatt, our Chairperson and Chief Executive Officer; Michael Benkowitz, our President and Chief Operating Officer; James Edgemond, our Chief Financial Officer and Treasurer; Dr. Leigh Peterson, our Executive Vice President of Product Development and Xenotransplantation; and Pat Poisson, our Executive Vice President of Strategic Development.

Note that James Edgemond and I will participate in a fireside chat and one-on-one meetings at the RBC Global Healthcare Conference in New York on May 19 as well as the Jefferies Global Healthcare Conference in New York on June 3. Our scientific, commercial and medical affairs teams will be present at the American Thoracic Society International Conference in Orlando, May 15 to the 21. Now I will turn the webcast over to Martine for an overview of our development pipeline and business activities. Martine?

Martine Rothblatt: Thank you, Harry. Okay, folks, it's going to be a great and exciting call today. UT is doing so freak amazing that it is hard to imagine any other mid-cap biotech right now with prospects as good as ours. Here's what I mean. We just proved beyond a shadow of a doubt with a p-value of less than 0.0001 that we have 2 different therapeutics in 2 different diseases of substantial size, each of which has been shown to produce better clinical outcomes than any other drug ever approved for either indication. Wow, that's got to sink in. I personally have not seen anything like that from a single pharma company, all accomplished within 6 months.

The 2 diseases we will be the best therapeutic for based on the completed Phase III trials are IPF with Tyvaso and PAH with ralinepag. Each of the 2 products will exceed our total revenues of today, a revenue run rate of $3 billion going to $4 billion by the end of 2027. Let's take ralinepag first. Every patient with PAH should be prescribed that once-daily pill because it actually gives them their best shot at clinical improvement. Specifically, we showed a threefold reduction in disease progression compared to background therapy. Ralinepag hit this and all other primary endpoints with better hazard ratios than selexipag and durably through 4 years.

Frankly, this is the drug I dreamed of in starting United Therapeutics. This is why we've been calling ralinepag a super prostacyclin. There is simply no reason that virtually every PAH patient shouldn't be on it. Hence, I fully expect within 2 years of launch, it will double our number of PAH patients to over 30,000 total. Next, let's look at Tyvaso for IPF. I said this will become the most prescribed drug for IPF because it improves forced vital capacity far more than the 3 existing drugs. It and only it boosted FVC to over 100 milliliters of oxygen and it did so quickly and it did so durably.

With tens of thousands of PAH patients and tens of thousands of IPF patients, it is nearly certain that these 2 drugs, once approved, will lap our 2027 $4 billion revenue run rate twice over. And coming right behind Tyvaso for IPF will be Tyvaso DPI for IPF and right behind that, Tyvaso SMI for IPF. Our goal is to leave no IPF patient behind regardless of how their particular body best absorbs Tyvaso. Now let's take a breath and reflect back on United Therapeutics. UT has been ahead of schedule as a habit. We were ahead of schedule on outcomes unblinding. We were ahead of schedule on TETON unblinding.

And today, I am excited to announce another ahead of schedule, the next blockbuster product to emerge from stealth mode in our Skunk Works division and inhaled formulation of our new chemical entity, ralinepag called RALDPI. In Stealth mode, a few months ago, we activated our exclusive option with MannKind for a second DPI. We now feel confident based on subsequent PK, computational biology via our proven CLIMB digital lung model and the results of the outcomes and TETON studies that this will be our biggest product ever. As you can see in the distributed market capture graph, we foresee our RALDPI product rising to tens of thousands of treated patients through PAH, ILD, IPF and PPF.

Indeed, we will need all the capacity of the Danbury, Connecticut MannKind production plant and all the capacity of the new United Therapeutics North Carolina DPI facility to keep up with the Tyvaso DPI and RALDPI demand. Now let's delve into the science to better appreciate what a generational product RALDPI will be for IPF. Ralinepag is the most potent member of the class of drugs that includes treprostinil. This is super clear from the extraordinary results of the outcome study. Second, it is now indisputable that this class of drugs via inhalation has significant antifibrotic effects as we proved in the 2 TETON trials.

ERGO, we very reasonably and scientifically expect RALDPI to show after further clinical trials that it is the best-in-class treatment for IPF and PPF. The scientific reason lies in the chemical differences between the new ralinepag molecule and the old treprostinil molecule, both of which are digitally mirrored in our CLIMB predictive computational biology model. Ralinepag has 8 fewer hydrogen atoms than treprostinil, but instead has a key nitrogen and a key chlorine item [indiscernible] that treprostinil lacks. These changes in molecular chemistry make all the difference in the world for pharmacodynamics and pharmacokinetics.

Now treprostinil is a very, very good molecule, delivering very, very good results, but not our treprostinil, not Insmeds, not liquidus treprostinil, none of these can ever be the super prostacyclin that is ralinepag. It is just not in their chemistry, but it is in ralinepag's chemistry. It is this change in chemistry that makes ralinepag a generational product for IPF. In summary, UT's long-standing multiple shots on goal strategy has now yielded its greatest reward, a proven once-daily NCE in PAH formulated to use a proven DPI drug device for the best-in-disease treatment of the largest indications to which we aim.

And as we march to this summit, we are rising through a series of great product stages that give us ever greater reach into the PAH and IPF community. Namely, we are rising through Tyvaso for ILD and IPF, Tyvaso DPI for ILD and IPF open-label extension, Tyvaso SMI or transmi for PAH, ILD and IPF and many more such combinations of products and diseases to treat, which are still in stealth mode in our Skunk Works division. Each incremental product indication platform that I just mentioned, each of these, we are now aggressively developing for new and existing markets, and each of these brings UT ever closer to the ultimate goal depicted in the forecast chart released today.

Thanks for listening and digesting all of this great science and great clinical development work. And now I'll turn to Michael to describe how the demand for our existing products from doctors and patients is strong as ever. Mike?

Michael Benkowitz: Thank you, Martine. That's a tough act to follow, but I'm going to do my best. Good morning, everyone. For the first quarter of 2026, we recorded $782 million in total revenue. Typical historical seasonality trends persisted in the first quarter, in addition to severe winter weather and pharmacy operations issues that slowed starts during the quarter. These have since been rectified, but it did impact our sales in the quarter, particularly in February. As discussed on our last earnings call, we expect to return to sequential growth in the near term. Turning to Tyvaso. Total revenue for the first quarter was $458 million.

While sales of nebulized Tyvaso lagged a little bit over the quarter, Tyvaso DPI contributed 9% year-over-year growth, driven by an increase in patient demand. Looking at the competitive landscape, it's clear the market for inhaled prostacyclins is attractive and growing. We built and lead this market and expect our proven expertise to continue to win in the long term. We see this competitive dynamic as fuel for sharper execution across the organization, enhancing our strategic focus while operating with greater tactical intensity as we continue to shift momentum back in our favor. Speaking of momentum, we are seeing favorable trends in our underlying demand metrics.

Coming out of the quarter, Tyvaso referrals or prescriptions rates are at approximately the same level they were before YUTREPIA launched. Patient shipments have grown for the last 5 months. Prescriber breadth and depth continue to grow, and we've seen a steady increase in patients graduating to higher doses of Tyvaso DPI with the launch of the 80-microgram single capsule and the 96-microgram and 112-microgram combination kits. Going forward, we're doubling down on what has always driven our success, relentless innovation, proven experience and patient obsession.

Additionally, the sales force investments we're making in anticipation of the ralinepag and IPF approvals will be deployed in the middle of this year to focus on expanding our reach and capturing more of the large addressable but yet uncaptured market in PH-ILD and expanding share in PAH with our existing commercial portfolio. We've built a durable, high-performing commercial engine, and we're confident in our ability to expand our core business while driving the next wave of growth in treresmi, ralinepag and IPF. To once again quickly recap, as Martine mentioned, both the TETON 1 and TETON 2 trials of nebulized Tyvaso in IPF were a resounding success and exceeded our highest expectations.

We look forward to filing a supplemental new drug application by the end of this summer and believe the highly compelling body of evidence across both the TETON studies could warrant an expedited approval through priority review to bring this therapy to those patients in need as quickly as possible. If we receive a standard review time line, we would expect to launch by Q2 of next year. And in parallel, we have already embarked on preparations for a product launch. Following IPF approval, we'll work with payers to secure coverage for the new indication as soon as possible. We recognize the substantial market opportunity that lies ahead, and we're fully prepared to seize it.

Coming back to ADVANCE OUTCOMES, the unprecedented top line results suggest ralinepag has the potential to revolutionize the treatment of pulmonary arterial hypertension as the first true once-a-day oral prostacyclin agonist. We believe this advancement could fundamentally shift the treatment paradigm, potentially positioning prostacyclins for earlier line usage in conjunction with ERAs and PDE-5s. With a differentiated clinical profile, combined with its convenient once-daily dosing, we foresee a multibillion-dollar opportunity in the market for oral ralinepag, where we expect to launch mid next year, assuming a smooth FDA approval on a standard review time line.

In summary, our goals over the near to medium term are to drive further growth in Tyvaso, the most prescribed inhaled prostacyclin and after anticipated FDA approvals for ralinepag to become the most prescribed prostacyclin for PAH and for nebulized Tyvaso to become the most prescribed therapy for IPF. To close, I want to recognize the intensity, discipline and patient-first commitment our commercial and medical affairs teams bring every day. We remain confident that our business is positioned to deliver sustained double-digit long-term growth. With that, I'll pass the call back over to Harry to start the Q&A session.

Harrison Silvers: Thanks, Michael. Operator, if you want to assemble the roster and start with the first question.

Operator: [Operator Instructions] Your first question comes from the line of Ash Verma of UBS.

Ashwani Verma: Congrats on all the progress. Maybe just on the IPF regulatory filing and how you're positioning yourself in the market. I know you had previously mentioned that you would do a bridging study for the DPI. And where are we on that? And do you think that by the time that you launch the IPF, you would have the DPI format available? And just as a quick follow-up, I wanted to understand just your thoughts on the JASCAYD or Nerandomilast launch metrics that are looking particularly strong. So do you think that is kind of like an indication of the pent-up demand in this market, given there isn't much of good options available?

And how does Tyvaso get positioned compared to JASCAYD when you launch it?

Harrison Silvers: All right. Thanks, Ash. [Operator Instructions]. Leigh, if you want to take the DPI to IPF component and then maybe Michael can follow up on JASCAYD.

Leigh Peterson: Yes. So for -- we're actually working with FDA to come up with our bridging strategy for IPF with the Tyvaso DPI. I think we've been discussing that before. We will likely do healthy volunteer PK compatibility studies, comparability studies and as well as patient studies to demonstrate safety and efficacy. And as far as the sample size and duration of those studies, again, we're still working with FDA to come up with a clinical development plan.

Michael Benkowitz: Yes. Just on the JASCAYD -- I think I'm going to address the question that you had on JASCAYD. Yes. So yes, Ash, we've been -- I mean, obviously, we're following that very closely. I do think that's a good proxy or a good analog and does suggest that there is a lot of pent-up demand for new therapies in IPF, given what's currently on the market. So I mean, yes, I guess the short answer is we agree with you, and that's really kind of how we're starting to think about potential launch curve. We're starting to have conversations with physicians now.

It's still a little bit on the early side because we were somewhat embargoed in what we could talk about with the New England Journal publication. But now that's behind us, we're able to have those conversations. And I think we're hearing from the physicians that they're very impressed by the data, very excited about bringing Tyvaso to market. I think we had an advisory board about a month or so ago where we had some of the -- like the top 15, I think, IPF treaters in the country. And we were asking a question around where are you going to use Tyvaso? You use it first line, you use it after JASCAYD, how do you think about this?

And they all said, it's going to be patient dependent. In some cases, they use Tyvaso first. In some cases, they may start JASCAYD. But at the end of the day, it doesn't matter because they fully expect that this disease is going to look a lot like what we see in PAH where it's combination therapy. So even if they're starting JASCAYD first, they're going to add Tyvaso on very quickly thereafter. So yes, we think the potential is, as Martine said in the beginning, just enormous in IPF.

Operator: Your next question comes from the line of Roanna Ruiz of Leerink Partners.

Roanna Clarissa Ruiz: So I was curious, how does your overall commercial strategy and peak sales and timing expectations change now that you're focusing on a few different levers like the triple combo pill for ralinepag, DPI for ralinepag and also thinking about the SMI?

Harrison Silvers: Thanks, Anna, for the question. Good to hear your voice this morning. Michael, do you want to take that one?

Michael Benkowitz: Sure, Roanna. Yes, I think we'll provide some more granularity as we start to kind of build out our forecast, we start to have more conversations with physicians about the different products and where they expect to use them. But I think high level, what Martine said in her opening remarks is right. I mean, if we're trending towards $4 billion run rate by next year, we think certainly with just ralinepag and the IPF indication regardless of the delivery device, that puts us on a path to more than double revenues over the next few years. That's what we're building for and aiming for.

How that breaks out between the different indications, different devices, like I said, I think we'll provide some more granularity on that as we get later in the year and build out our models.

Operator: Your next question comes from the line of Jessica Fye of JPMorgan.

Jessica Fye: I wanted to focus on ralinepag DPI. Can you just confirm this product coming out of stealth mode? Is that the once-daily inhaled product you've been alluding to in prior quarters? When should we expect that Phase I healthy volunteer PK/PD data comparing that product to oral ralinepag? And what led you to decide for DPI over SMI for ralinepag's new formulation?

Harrison Silvers: Thanks, Jess. Good to hear from you. Welcome back. I'll kick that over to Pat to answer on ralinepag DPI plans.

Patrick Poisson: So first, let me say we are excited to work with the MannKind development team again. What we were able to do with -- together with Tyvaso DPI, which was approved in less than 4 years from our engagement while contending with the pandemic, was really nothing short of incredible, and we expect an even better encore with RALDPI. So as mentioned in the MannKind press release this morning, we began work on RALDPI about 6 months ago. And we've made great progress with the completion of formulation development and the transition into manufacturing tox study supplies.

We've had a very positive pre-IND engagement with FDA, and we'll shortly be moving into some minimal nonclinical testing, which will be quickly followed by an IND in a Phase I study, which we believe will be completed before the end of the year. We believe the half-life of ralinepag, along with some other characteristics we are investigating are very promising for this to be a once-a-day product. And important to note that this will be without the addition of any release controlling materials, which need to be carefully studied for safety when used chronically. So I'll finish with, as they say in iCar racing, we are staying with hard tires and not making any pit stops.

Operator: Your next question comes from the line of Joseph [ Thorne ] of TD Cowen.

Joseph Thome: Maybe just to extend a little bit on the development program for RALDPI. Maybe how quickly can this move? Is the availability of the data for oral ralinepag helpful at all, maybe specifically for PAH? Could you go right into registration? Just trying to think about time lines relative to some competitors in the space.

Harrison Silvers: Joe, thanks for the question this morning. I think we'll kick that back over to Pat again.

Patrick Poisson: Yes. Another great question. Of course, the AVANCE OUTCOMES data was off the charts incredible. So that's very encouraging that RALDPI will be very effective to treat PAH, PH-ILD and IPF and PPF. So as far as the timing, I think long term, we're going to be able to move into PAH fairly quickly relative to our world in pharma as we'll be pursuing that approval with the solid dose. And certainly, the solid dose has been a big contributor to our engagement with FDA and really the minimal amount of pre-IND work that we have to do for RALDPI.

So I anticipate we'll complete the initial Phase I study by the end of the year, and we'll be rapidly be able to kick off studies for PAH efficacy as well as PH-ILD, IPF and PPF. So each of those will progress at different paces and -- but initially, PAH will be the first approval.

Operator: Your next question comes from the line of Lisa Walter of RBC Capital Markets.

Lisa Walter: On the 1x daily ralinepag DPI, just wondering if you can share more color on the formulation. Should we think of this as a ralinepag prodrug or another formulation with the lung targeting ligand? Or are relatively little additional flourishes needed to make ralinepag inhalable? Any color here would be helpful.

Harrison Silvers: Thanks, Lisa. Good to hear from you. Pat, you're at the star of the show today.

Patrick Poisson: All right. Thanks, Harry. So we'll be leveraging MannKind's crystal carrier IP for ralinepag, very similar to what we have for treprostinil. It is not going to be a prodrug. Now perhaps we investigate other polymorphs of ralinepag in the future, but initially, it's going to be the ralinepag molecule that we investigated for solid dose. So again, very similar formulation to the current treprostinil in using MannKind's crystal carrier IP.

Operator: Your next question comes from the line of Olivia Brayer of Cantor.

Olivia Brayer: Now that you are committing to developing a number of different formulations in IPF going forward, can you maybe just talk about which you think have the highest chances for success? And how you're thinking about nebulized versus DPI versus SMI and then also Tyvaso versus ralinepag for IPF patients specifically? And just kind of following up on that from a regulatory strategy perspective, anything you can say yet in terms of what that strategy is for getting some of these next formulations to patients? I mean it sounds like a bridging study for DPI, but what about the SMI formulation? And then when could you realistically start those ralinepag studies in IPF and PPF?

Harrison Silvers: Perhaps from a broader strategic standpoint, Michael can take that question and then maybe Leigh can follow up on the regulatory side.

Michael Benkowitz: Yes. I think from a strategic standpoint, our approach to IPF is very similar to what you've seen us over the last 30 years do in PAH, which is taking multiple shots on goal approach. And we started with Remodulin IV. We thought Remodulin subcu could be a better version of Remodulin just in terms of dealing with the potential for infections. And then we progressed to Tyvaso, we progressed to Orenitram. Now we're -- and then we looked at Tyvaso DPI, we look at -- and now we're ralinepag.

And I think the point of all that is that I think what we've uncovered in PAH, and we think this is true in IPF is that patients are like Snowflakes, right? They're not this homogenous group of people that all respond to the same drug delivery approach. And so there's a role for all of these products in PAH. And I think that's what we're going to see in IPF is we take multiple shots on goal. And I think we're very optimistic and confident in our ability to bring all of these products to market. And we think they're all going to have a role, right?

I think there's going to be some patients that are going to respond well to DPI. I mean you look over in PH-ILD, I mean, I think -- you still have a significant number of patients that are still on nebulizer even though you have the convenience of a DPI. So patients are -- they're unique. They all respond to different drugs and different delivery devices in different ways. And so the approach has always been, multiple shots on goal, we give patients options -- give patients options in terms of the way they can receive the drug.

And then from our standpoint, we're really kind of agnostic as to which one they choose as long as they're choosing one of our products. So strategically, that's how we think about these different devices and different NCEs and IPF. So Leigh, I don't know if you want to -- or Pat, you guys want to talk about the regulatory path.

Leigh Peterson: Yes. Actually, I just wanted to add on a little bit of color to what you said and with the patients or people or Snowflakes. Just keep in mind that with -- so we have the different sort of categories, we have the inhaled route versus the oral route. Now we know that oral for patients, especially if it's once a day, tends to be more convenient, but we also know that systemic vasodilators are generally contraindicated in patients with like PH-ILD or IPF, given the potential for worsening ventilation perfusion mismatch, VQ mismatch. And so that kind of separates that right there as to we imagine the inhaled would be more for this other population.

And then as far as the powder versus the SMI, some patients, it could be a convenience thing or a cough, some patients might be more sensitive to the powder versus the nebulizer. And so that's where that might fall out. And then as far as -- this is something we haven't really talked about too much. But even though treprostinil and ralinepag are both in the same class of drugs, they do bind -- Martine went through the chemistry of the actual molecular structure between the 2. And as such, they bind their receptors differently. Ralinepag is a really, really potent IP receptor agonist, whereas treprostinil binds multiple receptors, IP, EP2 and DPI.

And so there may be some differences with regard to efficacy there based on patient genetics. And so all of these things, again, just to reiterate that they really give us -- this really allows individual patients to get the absolute best treatment possible. And as far as the IP receptor goes, there's some recent data that -- recent preclinical data that IP receptor activation promotes alveolar regeneration during lung repair. And so -- and this is -- if you want to really get into the molecules and the pathways, it's versus this June p53 pathway.

And so I mean, there's coming out more and more evidence for these things and the class of molecules versus different mechanisms of action in these indications, whether it's PAH or PH-ILD or ILD or IPF or PPF or all of them. So anyway, I just wanted to add a little bit more there and then maybe Pat would want to talk about the regulatory aspect.

Patrick Poisson: Yes. I mean I think the regulatory strategy would proceed kind of as expected. So we'll have nebulized approved in IPF, and we'll conduct whatever agreed upon bridging study is necessary and then proceed directly with the filing from there. So I don't anticipate anything unusual.

Harrison Silvers: Thank you, Pat, Lee, Michael, 3 really wonderful answers. Operator, I think one more question we have time for.

Operator: Your last question comes from the line of Roger Song of Jefferies.

Jiale Song: Congrats for the quarter. Maybe -- I think in the update, you also have the PH-COPD Phase II about to start later this year. So curious about how should we think about the market opportunity and then also what the product formulation potential sequence for that indication, given we haven't talked about a lot of the combination device and the drug.

Harrison Silvers: Thanks, Roger. Leigh, perhaps you want to share a little bit of color on the PH-COPD study?

Leigh Peterson: Yes. So as far as the formulation, we're planning to use treprostinil SMA -- SMI, excuse me, for this and for PH-COPD. And we're planning on doing it the study in a couple of phases. We obviously have our Phase I where that's already ongoing with the treprostinil SMI in healthy volunteers. And then we're planning a Phase II study with PH-COPD patients, and that will be followed by a Phase III PH-COPD study. And we have several learnings through over the years that are being considered here with regard to patient populations, and we're really looking forward to starting these studies with these sort of enriched patient population eligibility criteria.

Harrison Silvers: Thank you, Leigh. Operator, you can go ahead and close the call.

Operator: Thank you for participating in today's United Therapeutics Corporation earnings webcast. A rebroadcast of this webcast will be available for replay for 1 week by visiting the Events and Presentations section of the United Therapeutics Investor Relations website at ir.unither.com. This concludes today's conference call. You may now disconnect.