Mirum Pharmaceuticals, Inc. (MIRM) - Q1 2026 10-Q Summary
Business Context and Reporting Period
This Quarterly Report on Form 10-Q covers the period ended March 31, 2026. Mirum Pharmaceuticals is a biopharmaceutical company focused on rare diseases with three approved medicines: LIVMARLI (maralixibat), Cholbam (cholic acid), and CTEXLI (chenodiol). The quarter was defined by the strategic acquisition of Bluejay Therapeutics, Inc. on January 23, 2026, adding the late-stage product candidate brelovitug for chronic hepatitis delta virus (HDV) to the pipeline.
Key Financial Metrics
| Metric (in thousands) | Q1 2026 | Q1 2025 |
|---|---|---|
| Product Sales, Net | $159,882 | $111,585 |
| Total Operating Expenses | $949,347 | $126,768 |
| Net Loss | $(790,155) | $(14,677) |
| Net Loss Per Share (Basic & Diluted) | $(13.43) | $(0.30) |
| Cash, Cash Equivalents & Investments | $420,612 | $391,400 (Dec 31, 2025) |
| Convertible Notes Payable (Principal) | $316,226 | $316,226 |
Note: Q1 2025 investment data is not explicitly provided in the text for direct comparison, but Q1 2026 unrestricted cash and investments totaled $420.6 million.
Material Changes vs. Prior Period
- Revenue Growth: Net product sales increased by $48.3 million (43%) year-over-year, driven by continued commercialization of Livmarli and Bile Acid Medicines.
- Acquisition Impact: The company recorded a $726.3 million charge for "Acquired in-process research and development" (IPR&D) related to the Bluejay acquisition. This non-cash charge was the primary driver of the increased net loss.
- Operating Expenses: Total operating expenses surged to $949.3 million from $126.8 million. Excluding the IPR&D charge, R&D expenses increased due to clinical activities for brelovitug, volixibat, and MRM-3379, plus one-time stock-based compensation of $15.4 million related to Bluejay.
- Capital Raise: In January 2026, the company completed a private placement of common stock and pre-funded warrants, raising net proceeds of approximately $259.9 million.
Guidance, Outlook, and Risks
- Liquidity: Management believes existing unrestricted cash, cash equivalents, and investments ($420.6 million) are sufficient to fund operations for at least the next 12 months.
- Convertible Notes: The 4.00% Convertible Senior Notes due 2029 are currently convertible at the option of holders for the quarter ending June 30, 2026, as the stock price exceeded 130% of the conversion price for the requisite period. The company may settle conversions in cash, stock, or a combination.
- Pipeline Milestones:
- Volixibat: NDA submission for PSC expected in H2 2026; approval/launch expected H1 2027.
- Brelovitug: Topline data from AZURE-1 and AZURE-4 trials expected H2 2026; potential BLA submission H1 2027.
- MRM-3379: Topline data from BLOOM Phase 2 study expected in 2027.
- Legal Proceedings: The company is engaged in patent litigation (LIVMARLI Patent Litigations) against Sandoz, Hetero, Biophore, and Zydus regarding generic versions of Livmarli. A 30-month stay on generic approval is currently in effect through March 29, 2029.
- Risks: Key risks include the uncertainty of clinical trial outcomes, reliance on third-party manufacturers, potential dilution from convertible notes or equity raises, and the impact of generic competition if patent litigation is unsuccessful.
Investor Verification Checklist
- Verify the conversion status of the $316.2 million convertible notes and the company's settlement preference (cash vs. stock) for the upcoming quarter.
- Confirm the integration progress of Bluejay Therapeutics and the timeline for brelovitug clinical trial data readouts.
- Monitor the status of LIVMARLI patent litigation and any potential rulings that could impact the 30-month stay on generic competition.
- Review the cash burn rate post-acquisition to ensure the $420.6 million liquidity runway remains sufficient given increased R&D spend.
- Assess the revenue mix and dependency on Takeda for Livmarli sales in Japan, noting the variable consideration estimates.