Mirum Pharmaceuticals, Inc. — FY2020 Form 10-K Summary
Reporting period: Fiscal year ended December 31, 2020; filed March 9, 2021. The filing is an annual report, not a standalone Q4 report. Mirum is a clinical-stage biopharmaceutical company developing oral ASBT inhibitors for rare cholestatic liver diseases. It had no approved products and no product revenue.
Business Context and Pipeline
- Maralixibat: Under development for pediatric Alagille syndrome (ALGS), progressive familial intrahepatic cholestasis (PFIC), and biliary atresia (BA).
- Volixibat: Under development for adult intrahepatic cholestasis of pregnancy (ICP), primary sclerosing cholangitis (PSC), and primary biliary cholangitis (PBC).
- The company initiated a rolling FDA NDA submission for maralixibat in ALGS in Q3 2020 and completed the submission in January 2021. The EMA was reviewing an MAA for maralixibat in PFIC2.
- Key expected milestones included potential ALGS launch in the second half of 2021, completion of MARCH-PFIC enrollment in Q2 2021 with topline data expected in early 2022, and additional volixibat trials beginning in 2021.
Financial Performance and Liquidity
| Metric | FY2020 | FY2019 | Change |
|---|---|---|---|
| Product revenue | $0 | $0 | No change |
| Research and development expense | $81.6 million | $43.0 million | +$38.6 million |
| General and administrative expense | $22.7 million | $11.8 million | +$10.9 million |
| Total operating expenses | $104.3 million | $54.7 million | +$49.6 million |
| Loss from operations | $(104.3) million | $(54.7) million | Higher loss |
| Net loss | $(103.3) million | $(52.6) million | Higher loss |
| Net loss per share | $(4.09) | $(4.58) | Improved per share due to higher share count |
| Net cash used in operating activities | $(89.1) million | $(39.4) million | Higher cash burn |
| Cash, cash equivalents and investments | $231.8 million | $140.0 million | +$91.8 million |
Operating and net margins are not meaningful because the company generated no revenue. Stock-based compensation was $12.6 million, compared with $6.1 million in 2019. Accumulated deficit was $173.2 million at year-end.
Material Changes Versus FY2019
- Research and development spending increased primarily because of manufacturing and NDA preparation, the $10.0 million PFIC2 MAA milestone, personnel growth, and new clinical activity for volixibat and maralixibat.
- General and administrative spending increased due to higher headcount, public-company costs, insurance, audit and tax fees, and commercial preparation for maralixibat.
- Cash increased primarily from equity offerings and the Oberland revenue-interest financing. FY2020 financing cash inflows were $181.3 million versus $127.2 million in FY2019.
- The company issued 6.15 million shares in underwritten offerings, 305,969 shares through its at-the-market program, and 509,164 shares in connection with the Oberland transaction.
- Shares outstanding, excluding shares subject to repurchase, increased to 29.8 million at December 31, 2020 from 22.6 million at December 31, 2019.
Debt, Financing and Liquidity
- In December 2020, Mirum received $50.0 million under a Revenue Interest Purchase Agreement, net proceeds of approximately $49.3 million after issuance costs. The related revenue-interest liability was $47.7 million at year-end.
- Oberland is entitled to tiered revenue interests on future maralixibat sales, initially 9.75% on annual sales up to $350 million and 2.00% on higher tiers, subject to contractual adjustments and an overall repayment cap based on amounts funded.
- The RIPA includes a senior security interest in certain assets, covenants, put rights, and potential repurchase obligations that could accelerate cash requirements under specified events.
- Management stated that cash, cash equivalents and investments were sufficient to fund current operations for at least the next 12 months, but additional financing will be required to support continued development and commercialization.
Outlook, Commentary and Risks
- Management expects operating expenses and losses to increase as clinical programs advance, regulatory submissions continue, commercialization preparations expand, and staffing grows.
- COVID-19 did not have a significant financial impact in FY2020, but it disrupted enrollment in the MARCH trial and could continue to affect clinical sites, regulators, suppliers, manufacturing, capital markets and timelines.
- Major execution risks include failure or delay of clinical trials, limited rare-disease patient populations, subjective pruritus endpoints, regulatory disagreement over trial data or natural-history comparisons, and the need for additional studies.
- Maralixibat safety monitoring includes gastrointestinal adverse events and isolated, reversible ALT elevations in some ALGS patients. The filing states that no drug-induced liver injury or liver-related morbidity or mortality had been reported across more than 1,600 study participants as of the filing date.
- The company relies on third-party contract research organizations and manufacturers and does not have long-term commercial manufacturing agreements for its product candidates.
- Mirum relies substantially on licensed intellectual property from Shire/Takeda, Pfizer, Satiogen and Sanofi. Future milestone payments and royalties could materially affect economics if products are commercialized.
- The company has no approved products, has never generated product sales, and expects continued losses and potential future equity dilution or other financing.
Investor Verification Checklist
- Verify FDA acceptance, review status and eventual decision for the ALGS NDA, including the actual approved indication and label.
- Verify MARCH-PFIC enrollment, topline results, regulatory pathway and whether approval could be limited to the nt-PFIC2 population.
- Verify cash burn, remaining liquidity, financing needs and the impact of the RIPA’s revenue-interest and put-option provisions.
- Review clinical-trial safety data, particularly gastrointestinal events, ALT elevations, higher-dose exposure and treatment of younger patients.
- Assess manufacturing readiness, supply continuity and qualification of commercial contract manufacturers.
- Monitor competitive developments, particularly Albireo’s odevixibat and other ASBT inhibitors or gene-therapy approaches.
- Review future milestone, royalty and licensing obligations and the strength and remaining term of Mirum’s method-of-use intellectual-property protection.