Mirum Pharmaceuticals, Inc. Common Stock Morgan Stanley 24th Annual Global Healthcare Conference

Yeah. Thanks for hosting. It's great to be here. I'll make a quick disclaimer on my end as well. We'll be making forward-looking statements so refer you to the SEC filings for Mirum for a more complete risk factor disclosure. A bit about Mirum. We are a company that's established just under 8 years ago and focused on pulling together high-impact medicines for rare disease that are often overlooked, missed by some of the bigger companies, but really compelling opportunities, not only from patient impact, but also as a business model and pulling these together in an efficient way. This year, we're on track for $680 million-$700 million of revenue across 3 approved medicines.

Really had a kind of emerging growth trend in one of our indications in particular with PFIC that I'm sure we'll spend some time talking about, and a pipeline that is very busy right now. Later this month actually, expecting to announce top line data of the AZURE-1 phase III study of brelovitug in hepatitis delta. We have a PDUFA date from one of our newly added programs in FOP. More readouts, 2 more phase IIIs reading out next quarter, and another study in PBC first quarter next year. All this on the back of entering into a regulatory conversation for PSC for volixibat as well. It's a busy stretch for Mirum, and kind of on the other side of this, see a real inflection on business performance from all of these data readouts and launches that we expect in the near term.

Exciting time across the board.

LIVMARLI is approved in two different indications, cholestatic pruritus due to Alagille syndrome and cholestatic pruritus due to PFIC. First approval in Alagille syndrome continues to be a growth driver. We, across the board, continue to see new patient starts. The response profile for most patients is quite meaningful and see strong compliance and persistence as well. That plays well for the brand over time, both this is U.S. as well as international performance. The PFIC indication was added subsequent to the Alagille syndrome launch, and it has been an interesting story over time. Initially, we saw this as a pediatric opportunity. That is what our field team was primarily targeting and finding the pediatric profile of a PFIC patient.

As we have been in market with LIVMARLI in pruritus due to PFIC, we have found that there is also a substantial underdiagnosed population in adults that actually have PFIC and have to date been labeled as idiopathic cholestasis. Really just an incomplete diagnosis in many of these adult cholestatic patients with pruritus. That is something that we have seen start to contribute to the top line over the past year. A very durable trend in everything we are seeing. In fact, we are now in the process of expanding the field commercial team to help support some of that patient finding and diagnosis, help build awareness of genetic testing and availability of it for adult patients. We estimate there is probably about 2,000 adult PFIC patients in the addressable market that are out there in the U.S. That is kind of one of the near-term drivers for the continued growth on the commercial business.

Yeah. LIVMARLI as a whole, we see it as a billion-plus brand opportunity driven by all these different components. Expand being a substantial contributor to it as well. It is a basket study, so it is a collection of ultra-rare causes of cholestatic pruritus that by definition in our discussion with the FDA are too small to run a standalone study in. A good number of them in the study are biliary atresia. That is probably the only one that is a little bit more common of the mix, and then very small numbers of other genetic and non-genetic causes of cholestasis that end up with a pruritus presentation. Study looks at both pediatric and adult patients. The primary endpoint that we are expecting next quarter is in a pediatric cohort. That is what the study was primarily powered and designed around.

Expect to see that as the top line next quarter of the pediatric patients with an identified subset looking at biliary atresia as well as a secondary because it is about half of the patient population. There are probably 500 pediatric patients in the U.S. that make up the addressable market that we have identified and sized. It is an early estimate, and it is hard to tell how big of an indication this could be in adult settings as well. There are some adult patients out there certainly, we just do not know quite how many. It is a nice add-on to what we are already seeing in Alagille syndrome and PFIC.

Yeah. Really the genesis of the study design came from physician interests and compassionate use case studies. We do have, not in a clinical trial format, but we do have anecdotal case study evidence seeing response in a number of these types of settings. Biliary atresia in particular, we have presented some of the case studies of a series of biliary atresia patients with cholestatic pruritus being treated, and it is what you would expect for an IBAT treatment. In a patient with cholestasis, elevated bile acids, and itch, you can expect to see a nice response in the clinical data that comes out from those studies.

Yeah. The bile acids, CTEXLI and CHOLBAM, have grown nicely with a dedicated team behind it. One of the things to note when we brought those products in, a realization we had is that the prescriber universe is not entirely hepatology and GI. Many of these patients, in particular for CTEXLI and for some of the CHOLBAM indications, are in medical genetics or neurology, and it's more of a patient finding and diagnosis effort that doesn't exclusively happen in hepatology. So we built a separate team that focuses on those other settings and the patient finding, and they've done a fantastic job over time with these products, and it's about having a dedicated effort that is a different strategy than what the liver team is doing, so it makes sense to have a different team staffed against it.