Mirum Pharmaceuticals — Third Quarter 2026 Earnings Summary

Financial Performance:

• Total revenue for the quarter ended September 30, 2026, was $185.7 million, compared to $133.0 million in the same period of 2025.
• Net product sales for the quarter were $185.7 million.
• LIVMARLI® net product sales reached $133.4 million, representing 45% year-over-year growth compared to Q3 2025.
• Bile Acid Medicines net product sales were $52.3 million, representing 28% year-over-year growth compared to Q3 2025.
• Total operating expenses were $245.5 million for the quarter, compared to $130.4 million in Q3 2025.
• Cost of sales was $35.2 million (including $6.7 million in intangible amortization and $0.6 million in stock-based compensation).
• Research and development expenses were $107.9 million (including $14.3 million in stock-based compensation and $42.1 million specifically for brelovitug development).
• Selling, general, and administrative expenses were $88.9 million (including $18.5 million in stock-based compensation).
• Non-recurring acquired in-process research and development (IPR&D) expense was $13.5 million.
• Net loss for the quarter was $40.8 million, or $(0.62) per share basic and $(0.87) per share diluted, compared to net income of $2.9 million in Q3 2025.
• Cash, cash equivalents, and investments totaled $500.5 million as of September 30, 2026, up from $391.4 million as of December 31, 2025.
• Total liabilities were $1,080.8 million as of September 30, 2026, compared to $528.1 million as of December 31, 2025, driven by a $731.3 million balance in convertible notes payable.
• Stockholders' equity was a deficit of $54.2 million as of September 30, 2026, compared to equity of $314.7 million as of December 31, 2025.

Guidance and Future Outlook:

• Full-year 2026 net product sales guidance was increased to $715 million to $720 million.
• Brelovitug AZURE-4 Phase 3 topline data in HDV is expected in Q4 2026.
• Volixibat VANTAGE Phase 2b study topline data in primary biliary cholangitis (PBC) is expected in Q1 2027.
• Volixibat New Drug Application (NDA) submission for primary sclerosing cholangitis (PSC) is planned for H1 2027.
• LIVMARLI supplemental NDA (sNDA) submission is planned for H1 2027.
• ATEBRIOZ supplemental NDA (sNDA) to expand indication to pediatric patients aged 6 to <12 years is planned for H1 2027.
• Brelovitug Biologics License Application (BLA) submission is planned for H1 2027, subject to supportive AZURE-4 results.
• MRM-3379 BLOOM Phase 2 topline data in fragile X syndrome (FXS) is expected in 2027.

Business Segments and Product Lines:

• Received U.S. FDA approval and launched ATEBRIOZ® (zilurgisertib) to reduce the volume of total new heterotopic ossification in adult and pediatric patients aged 12 years and older with fibrodysplasia ossificans progressiva (FOP).
• Reported positive results from Cohort 2 of the PROGRESS study of ATEBRIOZ in pediatric patients aged 6 to <12 years with FOP.
• LIVMARLI EXPAND Phase 3 study in additional rare cholestatic conditions, including biliary atresia, met the primary endpoint and achieved statistical significance across all prespecified secondary endpoints.
• Brelovitug AZURE-1 Phase 3 study in chronic hepatitis delta virus (HDV) met the primary endpoint; full results to be presented at AASLD.
• Brelovitug 48-week data from the Phase 2b portion of AZURE-1 demonstrated deepening viral suppression and increased rates of ALT normalization.
• Received U.S. FDA Orphan Drug Designation for brelovitug in HDV.
• Appointed Rob Myers, M.D., as Chief Medical Officer.

Market and Competitive Landscape:

• Mirum positions itself as a leading rare disease company with a global footprint of approved products and a broad pipeline.
• LIVMARLI has received Breakthrough Therapy designation for ALGS and PFIC type 2 and orphan designation for the treatment of ALGS and PFIC.
• Volixibat has been granted FDA Breakthrough Therapy designation for the treatment of cholestatic pruritus due to PSC and PBC.
• Brelovitug has FDA Breakthrough Therapy Designation for chronic HDV and Orphan Drug Designation for active hepatitis delta virus infection, along with PRIME and Orphan designations from the EMA.
• MRM-3379 has been granted FDA Fast Track designation for the treatment of FXS.

Risks and Challenges:

• Total operating expenses increased significantly year-over-year, primarily due to higher R&D costs and non-recurring IPR&D expenses.
• The company reported a net loss of $40.8 million for the quarter and a cumulative net loss of $898.1 million for the nine months ended September 30, 2026.
• Stockholders' equity turned into a deficit of $54.2 million as of September 30, 2026.
• LIVMARLI carries a limitation of use for PFIC type 2 patients with severe BSEP defects and warnings regarding liver injury and gastrointestinal problems.
• ATEBRIOZ is contraindicated in pregnancy and can cause fetal harm.
• CHOLBAM and CTEXLI carry warnings regarding exacerbation of liver impairment and potential liver injury.
• Forward-looking statements regarding clinical results, regulatory approvals, and commercial growth are subject to risks and uncertainties, including potential differences between anticipated and actual results.

Management Commentary and Tone:

• CEO Chris Peetz described the third quarter as an "important period of execution," highlighting the approval and launch of ATEBRIOZ and positive Phase 3 results.
• Management noted that positive results from AZURE-1 and EXPAND reinforce the potential of brelovitug and LIVMARLI to treat more patients.
• Peetz stated that these milestones position Mirum for "another meaningful inflection with five potential upcoming approvals and label expansions."
• The tone emphasizes continued momentum across the commercial business and disciplined execution across the late-stage rare liver portfolio.

Other Key Points:

• Mirum repurchased $20.0 million aggregate principal amount of its 4.00% convertible senior subordinated notes due 2029, representing approximately 25% of the outstanding notes.
• ATEBRIOZ is licensed from Incyte for worldwide development and commercialization.
• Brelovitug is a fully human monoclonal antibody designed to neutralize and remove hepatitis B and hepatitis D virions.
• MRM-3379 is a selective phosphodiesterase-4D (PDE4D) inhibitor designed to enhance cAMP signaling.
• Conference call details were provided for November 3 at 1:30 p.m. PT / 4:30 p.m. ET.