Mirum Pharmaceuticals, Inc. is a biopharmaceutical company dedicated to developing and commercializing innovative therapies for rare and orphan diseases. With a diverse portfolio of approved medicines and a robust pipeline of product candidates, Mirum has established itself as a rising leader in the rare disease space.
Business Overview and History
Mirum Pharmaceuticals, Inc. was incorporated in the State of Delaware in May 2018 and is headquartered in Foster City, California. The company was founded with the goal of transforming the treatment of rare diseases. In November 2018, Mirum entered into an Assignment and License Agreement with Shire International GmbH, which granted the company an exclusive, royalty-bearing worldwide license to develop and commercialize two product candidates - Livmarli and volixibat. As part of this agreement, Mirum was also assigned license agreements that Shire had with Satiogen Pharmaceuticals, Inc., Pfizer Inc., and Sanofi-Aventis Deutschland GmbH.
In September 2013, the FDA granted orphan drug status to Livmarli for the treatment of patients with progressive familial intrahepatic cholestasis (PFIC) and Alagille syndrome (ALGS) in the U.S. Mirum also received orphan drug designation for Livmarli for PFIC and ALGS in the EU. This early regulatory recognition highlighted the potential of Livmarli in addressing unmet needs in rare liver diseases.
In May 2022, Mirum completed the merger and acquisition of Satiogen Pharmaceuticals, Inc. This transaction resulted in Mirum obtaining all of Satiogen's licensing payments and intellectual property relating to Livmarli and volixibat, further strengthening the company's position in the rare disease space.
On August 31, 2023, Mirum completed the acquisition of assets from Travere Therapeutics, Inc. that were primarily related to the development, manufacture, and commercialization of chenodiol and Cholbam. Chenodal was approved for the treatment of radiolucent stones in the gallbladder and had received medical necessity recognition by the FDA for the treatment of cerebrotendinous xanthomatosis (CTX). Cholbam was approved by the FDA in 2015 for the treatment of bile acid synthesis disorders due to single enzyme deficiencies and adjunctive treatment of peroxisomal disorders. This strategic acquisition significantly expanded Mirum's commercial portfolio and strengthened its position in rare liver diseases.
Throughout its history, Mirum has faced various challenges, including the inherent risks associated with drug development, navigating the regulatory approval process, and establishing its commercial capabilities. However, the company has worked to overcome these obstacles and build a portfolio of approved medicines and product candidates targeting rare and orphan diseases.
Financial Performance and Liquidity
Mirum's financial position remains strong, with $293 million in cash, cash equivalents, and investments as of December 31, 2024. The company's total net product sales for the full year 2024 were $336.4 million, a significant increase from $178.9 million in 2023. This growth was primarily driven by the continued success of Livmarli, as well as the contribution from the newly acquired bile acid medicines.
Mirum's operating expenses for 2024 totaled $424.5 million, with research and development expenses of $140.6 million and selling, general, and administrative expenses of $202.2 million. The company's net loss for the year was $87.9 million, or $1.85 per share.
Despite the net loss, Mirum's business model has demonstrated the ability to generate positive cash flow. In 2024, the company reported operating cash flow of $10.3 million, and free cash flow of -$10.7 million. The company's strong liquidity position and cash flow generation provide the necessary resources to fund its ongoing operations and pipeline development activities.
Mirum has also demonstrated financial discipline, as evidenced by its ability to raise capital through strategic financing activities. In 2023, the company completed a $316.3 million convertible notes offering, which further strengthened its balance sheet and financial flexibility.
For the fourth quarter of 2024, Mirum reported revenue of $99.4 million, representing a year-over-year growth of 43%. The increase in Q4 2024 revenue was primarily driven by continued growth in sales of LIVMARLI and the addition of the bile acid medicines acquired from Travere Therapeutics in August 2023.
As of December 31, 2024, Mirum's debt-to-equity ratio stood at 1.408, while its current ratio and quick ratio were 3.104 and 2.927, respectively. These ratios indicate a strong liquidity position and the ability to meet short-term obligations.
The majority of Mirum's sales are generated in the United States, with some international markets including Canada and certain European countries. However, the company does not provide a detailed breakdown of performance by geographic markets.
Pipeline and Product Portfolio
Mirum's pipeline and product portfolio are the foundation of the company's growth strategy. The key assets include:
Livmarli (maralixibat): Livmarli is Mirum's lead approved product, indicated for the treatment of cholestatic pruritus in patients with Alagille syndrome (ALGS) and progressive familial intrahepatic cholestasis (PFIC). In 2024, Livmarli generated net product sales of $213.3 million, representing a 50% increase compared to 2023. This included $155 million from the US business and $59 million internationally. The company is also evaluating Livmarli in the Phase 3 EXPAND study for the treatment of cholestatic pruritus in additional rare cholestatic conditions.
Volixibat: Volixibat is Mirum's IBAT inhibitor product candidate in development for the treatment of primary sclerosing cholangitis (PSC) and primary biliary cholangitis (PBC). The VISTAS study in PSC and the VANTAGE study in PBC are both progressing well, with the company on track to complete enrollment in the second half of 2025 and 2026, respectively.
MRM-3379: Mirum's most recent pipeline addition is MRM-3379, a PDE4D inhibitor being developed for the treatment of Fragile X syndrome (FXS). The company plans to initiate a Phase 2 study for MRM-3379 in FXS in 2025, leveraging the promising proof-of-concept data for this mechanism in the rare genetic disorder.
Bile Acid Medicines: Through the acquisition of assets from Travere Therapeutics in 2023, Mirum added two approved medicines to its portfolio: Chenodal (chenodiol) and Cholbam (cholic acid). Chenodal was recently approved by the FDA for the treatment of cerebrotendinous xanthomatosis (CTX) in adults, providing Mirum with a new growth opportunity in this ultra-rare disease. In February 2025, the company received FDA approval to market chenodiol tablets under the brand name Ctexli for the treatment of adults with CTX. Cholbam is an FDA-approved treatment for pediatric and adult patients with bile acid synthesis disorders due to single enzyme defects and for adjunctive treatment of patients with peroxisomal disorders, including peroxisome biogenesis disorder-Zellweger spectrum disorder (PBD-ZSD). In 2024, Mirum's bile acid medicines had total net product sales of $123.1 million.
Mirum's diverse portfolio of approved medicines and promising pipeline assets positions the company well to address significant unmet needs in rare and orphan diseases. The company's focus on patient-centric innovation and its commitment to advancing its pipeline through robust clinical development efforts are key drivers of its long-term growth potential.
Regulatory and Commercial Milestones
Mirum has achieved several important regulatory and commercial milestones in recent years, further solidifying its position as a leader in the rare disease space.
In 2024, the company received FDA approval for Chenodal (chenodiol) for the treatment of cerebrotendinous xanthomatosis (CTX) in adults, marking the first and only approved therapy for this rare, progressive, and debilitating condition. This approval, coupled with the previously granted orphan drug designation, provides Mirum with seven years of market exclusivity in the United States.
Mirum also made significant progress with its lead product, Livmarli, expanding the approved indications for the treatment of cholestatic pruritus in patients with ALGS and PFIC. The company's ongoing Phase 3 EXPAND study aims to further expand Livmarli's label to include additional rare cholestatic conditions, representing a significant growth opportunity.
In the pipeline, Mirum achieved positive interim results for its IBAT inhibitor, volixibat, in the VISTAS study for PSC and the VANTAGE study for PBC. These results, along with the FDA's Breakthrough Therapy Designation for volixibat in PBC, have generated substantial enthusiasm and momentum for the continued development of this product candidate.
Mirum's commercial execution has also been impressive, with the company reporting total net product sales of $336.4 million in 2024, exceeding the upper end of its guidance range. This strong performance was driven by the continued success of Livmarli, as well as the contribution from the newly acquired bile acid medicines.
Risks and Challenges
While Mirum has made significant strides in transforming the treatment of rare diseases, the company faces several risks and challenges that investors should be aware of:
1. Regulatory and Clinical Development Risks: The successful development and approval of Mirum's pipeline assets, including volixibat and MRM-3379, are subject to the inherent risks and uncertainties associated with the drug development process. Delays or setbacks in the clinical trials or regulatory approval process could impact the company's long-term growth.
2. Competition and Pricing Pressures: Mirum operates in a highly competitive rare disease space, and the company may face challenges from existing or emerging therapies targeting the same indications. Pricing pressure from payers and healthcare systems could also impact the commercial success of Mirum's approved products.
3. Reliance on Third-Party Manufacturers and Suppliers: Mirum is dependent on third-party manufacturers and suppliers for the production and distribution of its approved medicines and product candidates. Any disruptions or quality issues in the supply chain could adversely affect the company's operations and financial performance.
4. Intellectual Property Risks: Mirum's success depends on its ability to protect its intellectual property rights, including patents and trade secrets. The company may face challenges in maintaining and defending its IP portfolio, which could lead to competition from generic or biosimilar products.
5. Geopolitical and Macroeconomic Factors: Mirum's global operations and supply chain expose the company to risks related to geopolitical tensions, trade disputes, and macroeconomic conditions, such as currency fluctuations, inflation, and potential disruptions in the financial markets.
Despite these risks, Mirum's strong commercial execution, robust pipeline, and disciplined financial management position the company well to navigate the challenges and continue its transformation of rare disease treatment.
Future Outlook and Guidance
Looking ahead, Mirum is positioned for continued growth and value creation. The company has provided guidance for 2025, expecting global net product sales to be in the range of $420 million to $435 million, representing a significant increase from the $336.4 million reported in 2024. This guidance represents an expected increase of close to $100 million compared to 2024.
This growth is expected to be driven by the continued momentum of Livmarli in ALGS and PFIC, as well as the contribution from the bile acid medicines, including the recently approved Chenodal for CTX. Mirum's pipeline assets, such as volixibat and MRM-3379, also hold substantial promise and could provide additional avenues for long-term value creation.
The company expects to be cash flow positive again in 2025, continuing the trend from 2024 where the business was cash flow positive. This financial stability, coupled with the $293 million in cash, cash equivalents, and investments at the end of 2024, provides Mirum with a strong foundation to support its growth initiatives.
The company's strategic focus on rare and orphan diseases, coupled with its commitment to innovation and patient-centric approach, positions Mirum as a leader in the transformation of rare disease treatment. As the company continues to execute on its growth strategy, investors can expect Mirum to remain at the forefront of the rare disease landscape.
Human Capital Management
As of December 31, 2024, Mirum Pharmaceuticals employed 322 full-time employees, 48 of whom hold Ph.D. or M.D. degrees. The company's employees are located primarily in the United States (241) and Europe (74), with 7 in Canada. This diverse and highly skilled workforce underscores Mirum's commitment to attracting and retaining top talent in the biopharmaceutical industry.
The company has not reported any issues with its workforce or labor relations, indicating a stable and productive work environment. Mirum's ability to maintain a strong team of professionals across various disciplines is crucial for its continued success in the competitive rare disease market.
Industry Trends
The rare disease pharmaceutical market has seen strong growth in recent years, with a compound annual growth rate (CAGR) of approximately 11% from 2018 to 2023. This growth has been driven by increased disease awareness, expanded access to genetic testing, and the development of novel therapies to address unmet medical needs.
Mirum is well-positioned to capitalize on these industry trends, with its focus on developing and commercializing treatments for rare diseases. The company's approved medicines - LIVMARLI, CHOLBAM, and CTEXLI (chenodiol) - as well as its pipeline of product candidates, including volixibat and MRM-3379, align well with the growing demand for innovative therapies in the rare disease space.
Conclusion
Mirum Pharmaceuticals has established itself as a rising star in the rare disease space, with a diverse portfolio of approved medicines and a robust pipeline of product candidates. The company's strong commercial execution, innovative pipeline, and disciplined financial management have positioned it for continued growth and value creation.
By leveraging its expertise in rare disease drug development and commercialization, Mirum is poised to address significant unmet needs and transform the lives of patients suffering from debilitating rare and orphan conditions. As the company continues to execute on its strategic priorities, investors can look forward to Mirum's continued rise as a leader in the rare disease field.