8-K: Mirum Exceeds 2025 Sales Guidance, Boosts 2026 Outlook

Mirum Pharmaceuticals announced preliminary unaudited 2025 net product sales exceeding guidance, provided strong 2026 outlook, and detailed pipeline advancements including a proposed acquisition.

Summary

• Preliminary unaudited 2025 net product sales reached approximately $520 million, surpassing the upper end of guidance.
• 2026 global net product sales are expected to be between $630 million and $650 million.
• The proposed acquisition of Bluejay Therapeutics is expected to close in mid-to-late January 2026, adding brelovitug for chronic hepatitis delta virus (HDV) to the pipeline.
• LIVMARLI net product sales for 2025 were approximately $359 million, including $243 million in US sales, representing 69% year-over-year growth.
• CHOLBAM and CTEXLI net product sales for 2025 were approximately $161 million, representing 31% year-over-year growth.
• Cash, cash equivalents, and investments are expected to be approximately $392 million as of December 31, 2025, up from $292.8 million as of December 31, 2024.
• Achieved positive cash flow from operations in 2025.
• The timing for the LIVMARLI EXPAND Phase 3 study has been accelerated, with topline data now expected in Q4 2026.
• Volixibat VISTAS study in primary sclerosing cholangitis (PSC) topline data is expected in Q2 2026.
• Bluejay Therapeutics AZURE Phase 3 studies of brelovitug in HDV have topline data expected in H2 2026 (AZURE 1 & 4) and H1 2028 (AZURE 2 & 3).
• Two private placements, for aggregate gross proceeds of approximately $268.5 million, are expected to be completed concurrently with the closing of the proposed acquisition.

Sentiment

Score: 9

Explanation: The filing presents exceptionally strong preliminary financial results for 2025, exceeding guidance, coupled with robust 2026 projections and significant pipeline advancements, including a strategic acquisition and accelerated clinical trial timelines. The positive cash flow achievement further underscores financial strength. The only minor detraction is the 'preliminary and unaudited' nature of some figures, but the overall tone and content are highly positive.

Positives

• Preliminary unaudited 2025 net product sales of approximately $520 million exceeded the upper end of guidance.
• Strong 2026 global net product sales guidance of $630 million to $650 million.
• LIVMARLI net product sales grew 69% year-over-year to approximately $359 million in 2025.
• CHOLBAM and CTEXLI net product sales grew 31% year-over-year to approximately $161 million in 2025.
• Achieved positive cash flow from operations in 2025.
• Year-end cash, cash equivalents, and investments increased to approximately $392 million from $292.8 million in 2024.
• Accelerated timing for LIVMARLI EXPAND Phase 3 study, with topline data now expected in Q4 2026.
• Proposed acquisition of Bluejay Therapeutics adds a late-stage asset, brelovitug for HDV, with FDA Breakthrough Therapy and EMA PRIME designations.
• Multiple upcoming clinical catalysts with topline data expected for Volixibat VISTAS (PSC) in Q2 2026 and brelovitug AZURE-1 (HDV) in H2 2026.
• Received FDA approval of LIVMARLI tablets and CTEXLI for cerebrotendinous xanthomatosis (CTX).
• LIVMARLI oral solution approved in Japan for the treatment of cholestatic pruritus in patients with Alagille syndrome (ALGS) and progressive familial intrahepatic cholestasis (PFIC).
• Expanded global footprint with commercial access in 33 countries.

Risks

• Actual results may differ materially from forward-looking statements due to various risks and uncertainties associated with Mirum's business in general.
• The impact of geopolitical and macroeconomic events could adversely affect operations and financial results.
• Risks described in Mirum's Quarterly Report on Form 10-Q for the quarter ended September 30, 2025, and subsequent SEC filings could materialize.
• The proposed acquisition of Bluejay Therapeutics may not be completed for various reasons, impacting pipeline expansion.
• The results, enrollment, conduct, and progress of Bluejay's ongoing studies for its product candidates are subject to uncertainties.
• The results, enrollment, conduct, and progress of Mirum's ongoing and planned studies for its product candidates, including in-licensed product candidates, are not guaranteed.
• The costs of business strategy, commercialization plans, and development programs could exceed expectations.
• The financial impact or revenues from any commercialization undertaken may not meet projections.
• The ability to obtain necessary regulatory approvals for product candidates or market acceptance of approved products is uncertain.
• Dependence on third-party clinical research organizations, manufacturers, suppliers, and distributors poses operational risks.
• The impact of competitive products and therapies could affect market share and profitability.
• The ability to obtain necessary additional capital for future operations or acquisitions is not assured.
• The ability to attract and retain key employees is crucial for continued success.
• The ability to manage the growth and complexity of the organization, especially with acquisitions, presents challenges.
• The ability to maintain, protect, and enhance intellectual property is critical for product exclusivity.
• The ability to continue to stay in compliance with applicable laws and regulations is an ongoing requirement.
• LIVMARLI can cause serious side effects, including liver injury, gastrointestinal problems (diarrhea, stomach pain), and can worsen Fat Soluble Vitamin (FSV) Deficiency.
• CHOLBAM can exacerbate liver impairment, and concurrent elevations of serum gamma glutamyltransferase (GGT) and alanine aminotransferase (ALT) may indicate overdose.
• CTEXLI can cause liver injury, requiring careful monitoring of liver function.

Future Outlook

Mirum Pharmaceuticals expects continued strong commercial growth in 2026, with global net product sales projected to be between $630 million and $650 million. The company anticipates multiple late-stage clinical catalysts, including topline data for Volixibat VISTAS in PSC in Q2 2026, accelerated topline data for LIVMARLI EXPAND in Q4 2026, and topline Phase 3 data for brelovitug in HDV in H2 2026, assuming the completion of the Bluejay Therapeutics acquisition. Mirum also aims to achieve positive cash flow from operations in 2027.

Management Comments

• "2025 was an excellent year for Mirum, reflecting the strength and scalability of our purpose-built rare disease operating model." Chris Peetz, Chief Executive Officer.
• "We delivered strong global commercial growth, advanced multiple late-stage clinical programs and are expanding our pipeline with the proposed acquisition of Bluejay Therapeutics and brelovitug for HDV." Chris Peetz, Chief Executive Officer.
• "With a strong financial foundation, deep commitment to patients and multiple upcoming clinical catalysts, we enter 2026 well positioned to drive continued execution and value creation." Chris Peetz, Chief Executive Officer.

Industry Context

Mirum Pharmaceuticals operates in the highly specialized and high-value rare disease sector, characterized by significant unmet medical needs and often premium pricing for approved therapies. The proposed acquisition of Bluejay Therapeutics and its brelovitug asset for chronic hepatitis delta virus (HDV) aligns with a broader industry trend of companies seeking to expand their portfolios in orphan indications, particularly those with Breakthrough Therapy designations, to leverage existing commercial infrastructure and expertise in rare liver diseases. The focus on IBAT inhibitors (LIVMARLI, Volixibat) and other novel mechanisms for cholestatic and genetic disorders positions Mirum within a competitive landscape that includes other rare disease specialists and larger pharmaceutical companies with orphan drug divisions. The strong commercial growth of LIVMARLI and the expansion into new geographies demonstrate effective execution in a market that rewards specialized commercial models.

Comparison to Industry Standards

• Mirum's 69% year-over-year growth for LIVMARLI and 31% for CHOLBAM/CTEXLI in 2025 demonstrates robust performance, often exceeding typical growth rates for established rare disease products, especially considering the ultra-rare nature of the conditions, which can be compared to the early growth phases of successful orphan drugs like those from Alexion Pharmaceuticals (now AstraZeneca Rare Disease).
• The acquisition of Bluejay Therapeutics and brelovitug, an asset with FDA Breakthrough Therapy and EMA PRIME designations, is comparable to strategic moves by companies like Sarepta Therapeutics or BioMarin Pharmaceutical, which frequently acquire or license late-stage assets in rare diseases to bolster their pipelines and market presence, indicating a strong strategic fit within the rare disease M&A landscape.
• The development of IBAT inhibitors like LIVMARLI and Volixibat places Mirum in a competitive space with other companies developing similar mechanisms for cholestatic liver diseases, such as Ipsen (formerly Albireo Pharma) with Bylvay (odevixibat) for PFIC and ALGS, indicating a validated therapeutic approach within the industry and a competitive market for these therapies.
• Achieving positive cash flow from operations in 2025, while simultaneously investing in pipeline expansion and acquisitions, is a strong indicator of financial health and operational efficiency, often seen in more mature and successful rare disease companies, setting a high standard for capital management in the sector.

Stakeholder Impact

• Shareholders: Positive impact due to strong financial performance, exceeding guidance, increased cash balance, and pipeline expansion through acquisition, potentially leading to increased share value.
• Patients: Positive impact through accelerated development of new therapies (LIVMARLI EXPAND, brelovitug for HDV, MRM-3379 for FXS) addressing high unmet medical needs in rare diseases.
• Employees: Potential for growth and expanded opportunities due to company expansion and pipeline diversification.
• Creditors: Improved financial health and positive cash flow from operations enhance the company's creditworthiness.

Next Steps

• Closing of the proposed acquisition of Bluejay Therapeutics in mid-to-late January 2026.
• Completion of two private placements concurrently with the Bluejay acquisition.
• Presentation at the J.P. Morgan Healthcare Conference on January 14, 2026.
• Topline data expected for Volixibat VISTAS study in PSC in Q2 2026.
• Interim data expected for Bluejay Therapeutics AZURE-1 study in HDV in Q2 2026.
• Completion of enrollment for LIVMARLI EXPAND Phase 3 study in H1 2026.
• Completion of enrollment for Volixibat VANTAGE study in PBC in H2 2026.
• Topline data expected for LIVMARLI EXPAND Phase 3 study in Q4 2026.
• Topline Phase 3 data expected for Bluejay Therapeutics AZURE-1 and AZURE-4 studies in HDV in H2 2026.
• Brelovitug HDV BLA Submission in H1 2027.
• Volixibat VANTAGE (PBC) topline results in H1 2027.
• Topline results for MRM-3379 BLOOM Phase 2 study in FXS in 2027.
• Topline Phase 3 data expected for Bluejay Therapeutics AZURE-2 and AZURE-3 studies in HDV in H1 2028.

Key Dates

Recommendation

Mirum Pharmaceuticals has demonstrated exceptional operational and financial performance, significantly exceeding its 2025 net product sales guidance and providing a robust outlook for 2026. The company achieved positive cash flow from operations and substantially increased its cash reserves. Strategically, the proposed acquisition of Bluejay Therapeutics adds a high-potential, late-stage asset (brelovitug for HDV) with Breakthrough Therapy designation, further diversifying and strengthening the pipeline. The acceleration of key clinical trial timelines, such as for LIVMARLI EXPAND, indicates efficient R&D execution and brings potential market opportunities closer. These factors, combined with a strong intellectual property portfolio and a clear path to multiple registrational readouts, position Mirum for sustained growth and value creation, making it a compelling 'strong buy' for investors.

Keywords

Mirum Pharmaceuticals, MIRM, Rare Disease, Financial Results, 2025 Sales, 2026 Guidance, LIVMARLI, maralixibat, CHOLBAM, CTEXLI, chenodiol, Bluejay Therapeutics, Acquisition, brelovitug, HDV, Hepatitis Delta Virus, Volixibat, PSC, PBC, Alagille Syndrome, PFIC, Cholestatic Pruritus, Fragile X Syndrome, MRM-3379, Clinical Trials, Pipeline, Biotechnology, Pharmaceuticals