Mirum Pharmaceuticals (NASDAQ:MIRM) reported third-quarter net product sales of $186 million and raised its full-year 2026 net product sales guidance to $715 million to $720 million, citing continued growth of LIVMARLI and its bile acid medicines as well as progress across its late-stage pipeline.
Chief Executive Officer Chris Peetz said the company is entering a period of commercial growth and potential regulatory activity, with five potential approvals or label expansions under development. Mirum expects to be cash flow positive next year, according to Peetz.
Commercial sales growth drives higher outlook
Through the first nine months of 2026, Mirum recorded approximately $522 million in net product sales, a figure Chief Financial Officer Eric Bjerkholt said equaled the company’s full-year 2025 revenue.
President and Chief Operating Officer Peter Radovich said LIVMARLI growth in Alagille syndrome continued to be supported by new patient starts, treatment persistence and weight-based dose increases. He identified adult patients with progressive familial intrahepatic cholestasis, or PFIC, as the largest driver of current growth. Mirum estimates there are at least 2,000 addressable adult PFIC patients in the U.S., although it said most remain undiagnosed.
Radovich said the company has seen a cadence of roughly $10 million to $15 million in quarter-over-quarter total revenue growth and expects that trend to continue through 2027. Growth was also reported across the company’s Alagille syndrome and bile acid medicine businesses.
Regarding the bile acid franchise, Peetz said CHOLBAM is beyond its orphan-drug exclusivity period, while CTEXLI retains orphan protection. He said Mirum has not seen a market entrant for either product. Bjerkholt added that Takeda-related LIVMARLI revenue was minimal in the third quarter and that Mirum does not expect new Takeda orders in the fourth quarter.
ATEBRIOZ launch begins following September approval
Mirum received approval for ATEBRIOZ in September for adults and pediatric patients ages 12 and older with fibrodysplasia ossificans progressiva, or FOP, and began its U.S. launch in October.
Radovich said early feedback from patients, caregivers and physicians has been positive, though he emphasized that the launch remains in its initial weeks. The company’s near-term priorities are patient identification and access.
Management expects ATEBRIOZ adoption to develop faster than LIVMARLI’s initial launch trajectory. Radovich noted that approximately 50% of addressable Alagille syndrome patients have started LIVMARLI since its original approval about five years ago, while the product continues to grow.
Chief Medical Officer Rob Myers said results from cohort two of the pivotal PROGRESS study extended ATEBRIOZ findings to children ages 6 to under 12. According to Myers, the results showed reductions in heterotopic ossification, encouraging joint-mobility improvements and a safety profile consistent with that observed in older patients. Mirum plans to submit a supplemental NDA in the first half of 2027 to seek expansion into that younger age group.
Pipeline readouts and regulatory submissions ahead
Mirum expects a series of clinical and regulatory milestones over the coming quarters. The company expects results from the AZURE-4 Phase III study of brelovitug in hepatitis delta virus, or HDV, during the fourth quarter. It also expects the VANTAGE study readout for volixibat in primary biliary cholangitis, or PBC, during the first quarter of 2027.
Management said it is pursuing five potential regulatory submissions:
- An NDA for volixibat in primary sclerosing cholangitis, or PSC;
- An NDA for volixibat in PBC;
- A biologics license application for brelovitug in HDV;
- A supplemental NDA for ATEBRIOZ in younger FOP patients; and
- A supplemental NDA for LIVMARLI based on the EXPAND study.
The company continues to target a first-half 2027 NDA submission for volixibat in PSC. Peetz said Mirum is seeking multiple interactions with the Food and Drug Administration to build familiarity with the VISTAS dataset before filing, rather than necessarily seeking complete alignment in every interaction. He said the company remains confident in its planned timing.
Myers said the positive Phase III EXPAND study of LIVMARLI met its primary endpoint and all prespecified secondary endpoints, with particularly encouraging results in biliary atresia. He also described the Phase III AZURE-1 results for brelovitug as demonstrating improvements in virologic and liver disease activity measures.
At the American Association for the Study of Liver Diseases meeting, Mirum plans to present full 24-week AZURE-1 Phase III results, 48-week Phase IIb data and two-year findings in patients with cirrhosis from an earlier Phase II study. Myers said the longer-term data indicate continued virologic suppression and improvements in ALT normalization and liver stiffness with treatment.
For volixibat in PBC, Peetz said interim VANTAGE data showed more than a two-point placebo-adjusted improvement in itch measures. Myers said the company has conducted work validating the Adult ItchRO measure and believes that magnitude of reduction is clinically important.
Expenses, cash position and capital structure
Mirum reported a high-50% cash contribution margin from its commercial business during the quarter and approximately $4 million of cash used in operations.
On a cash basis, third-quarter operating expenses totaled approximately $245 million, including $28 million in cost of sales, $70 million in selling, general and administrative expenses, and $94 million in research and development. The company also reported $13 million in in-process research and development and $40 million in stock-based compensation, depreciation and amortization expense.
Bjerkholt said cash-based R&D spending represented approximately 50% of revenue and is expected to remain at about that level for two more quarters before declining rapidly. He said the company expects R&D to decrease to about 10% of revenue over the longer term.
During September, Mirum repurchased $20 million in aggregate principal amount of its 2029 convertible notes for approximately $62 million in cash. The transaction followed the company’s second-quarter issuance of $690 million in zero-coupon convertible notes due 2032 and settlement of 75% of outstanding 2029 notes. Bjerkholt said the actions reduced the outstanding balance of the 2029 notes by more than 80%.
Mirum ended September with approximately $500 million in cash, cash equivalents and investments.
About Mirum Pharmaceuticals (NASDAQ:MIRM)
Mirum Pharmaceuticals, Inc is a biopharmaceutical company focused on developing and commercializing treatments for rare diseases, particularly disorders affecting the liver and bile acid pathways. The company’s medicines are designed to address conditions with limited treatment options and to improve outcomes for children and adults living with serious chronic diseases.
Mirum’s lead product is LIVMARLI (maralixibat), an oral bile acid transport inhibitor used to treat cholestatic pruritus, or severe itching caused by impaired bile flow, in patients with Alagille syndrome and progressive familial intrahepatic cholestasis.
