Mirum Pharmaceuticals reported a net loss of $40.77 million

Item 6.

Exhibits

105

Signatures

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SUMMARY OF RISKS ASSOCIATED WITH OUR BUSINESS

An investment in shares of our common stock involves a high degree of risk. Below is a list of the more significant risks associated with our business. This summary does not address all of the risks that we face. Additional discussion of the risks listed in this summary, as well as other risks that we face, are set forth under Part II, Item 1A, "Risk Factors" in this Quarterly Report on Form 10-Q.

• The success of our business depends, in part, on our ability to market and sell our approved medicines profitably.¹

• If we are unable to adequately grow, maintain and scale our marketing and sales capabilities or enter into or maintain rights pursuant to agreements with third parties to market and sell our approved medicines, we may not be able to generate viable revenues.

• Our approved medicines or any one of our product candidates, if approved, may fail to achieve the market acceptance among physicians, patients and others in the medical community necessary for commercial success.

• We rely completely on third parties to manufacture and distribute our clinical and commercial drug supplies, including certain sole-source suppliers and manufacturers.¹ These third parties may fail to obtain and maintain regulatory approval for their facilities, fail to provide us with sufficient quantities of drug substance, drug product, or labeled finished product in a timely fashion, or fail to do so at acceptable quality levels or prices.

• Our business depends, in part, on the success of our product candidates, each of which requires significant clinical testing before we can seek regulatory approval and potentially launch commercial sales.

• We have encountered and may continue to encounter delays and difficulties enrolling patients in our clinical trials, and as a result, our clinical development activities could be delayed or otherwise adversely affected.²

• Our clinical trials may fail to adequately demonstrate the safety and efficacy of our product candidates, which could prevent or delay regulatory approval and commercialization.¹

• Clinical drug development involves a lengthy and expensive process with uncertain outcomes, and results of earlier studies and trials may not be predictive of future trial results.

• Any delays in the commencement or completion, or termination or suspension, of our clinical trials could result in increased costs for us, delay or limit our ability to generate revenue and adversely affect our commercial prospects.

• Our product candidates are subject to extensive regulation and compliance, which is costly and time consuming, and such regulation may cause unanticipated delays or prevent the receipt of the required approvals to commercialize our product candidates.

• We face significant competition from other biotechnology and pharmaceutical companies with products that may directly or indirectly compete with ours, and our operating results will suffer if we fail to compete effectively.

• We may fail to realize all of the anticipated benefits of our commercial and product candidate acquisitions or those benefits may take longer to realize than expected.

• We depend on intellectual property licensed from third parties and termination of any of these licenses could result in the loss of significant rights, which would harm our business.

• We may need substantial additional financing to continue our commercialization efforts for our approved medicines, develop our product candidates, license or acquire new product candidates and approved medicines and implement our operating plans.² If we fail to obtain additional financing when needed, we may be forced to delay, reduce or eliminate our product development programs or commercialization efforts.

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• We do not currently have patent protection or regulatory exclusivity for certain of our approved medicines or rely on regulatory exclusivity. If we are unable to obtain and maintain sufficient intellectual property protection for our approved medicines and our product candidates, or if the scope of the intellectual property protection is not sufficiently broad, our competitors could develop and commercialize products similar or identical to ours, and our ability to successfully commercialize our approved medicines and our other product candidates, if approved, may be adversely affected.

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PART I—FINANCIAL INFORMATION

Item 1. Financial Statements.

Mirum Pharmaceuticals, Inc.

Condensed Consolidated Balance Sheets

(Unaudited)

(In thousands, except share and per share data)

September 30,

2026 December 31,

2025

(Note 2)

Assets

Current assets:

Prepaid expenses and other current assets 31,108 18,140

Operating lease right-of-use assets 11,355 8,741

Liabilities and Stockholders' (Deficit) Equity

Current liabilities:

Accounts payable $ 13,646 $ 9,614

Holdback liabilities, current 24,800 —

Accrued expenses and other current liabilities 244,634 196,185

Convertible notes payable, net, noncurrent 731,250⁸ 309,797

Holdback liabilities, noncurrent 44,653 —

Commitments and contingencies

Stockholders' (deficit) equity:

Preferred stock, $ 0.0001 par value; 10,000,000 shares authorized, and no shares issued and outstanding as of September 30, 2026 and December 31, 2025

— —

Accumulated other comprehensive (loss) income ( 2,056 ) 351

Total stockholders' (deficit) equity ( 54,186 )⁹ 314,690

Total liabilities and stockholders' (deficit) equity $ 1,026,613 $ 842,813

The accompanying notes are an integral part of these unaudited condensed consolidated financial statements.

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Mirum Pharmaceuticals, Inc.

Condensed Consolidated Statements of Operations

(Unaudited)

(In thousands, except share and per share data)

Three Months Ended September 30, Nine Months Ended September 30,

The accompanying notes are an integral part of these unaudited condensed consolidated financial statements.

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Mirum Pharmaceuticals, Inc.

Condensed Consolidated Statements of Comprehensive Income (Loss)

(Unaudited)

(In thousands)

Three Months Ended September 30, Nine Months Ended September 30,

The accompanying notes are an integral part of these unaudited condensed consolidated financial statements.

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Mirum Pharmaceuticals, Inc.

Condensed Consolidated Statements of Stockholders' (Deficit) Equity

(Unaudited)

(In thousands, except share amounts)

Common Stock Additional

Paid-In

Capital

Accumulated

Deficit

Accumulated

Other

Comprehensive

Income (Loss)

Total

Stockholders'

Equity (Deficit)

Shares Amount

Balance as of December 31, 2025 51,896,391 $ 5 $ 981,878 $ ( 667,544 ) $ 351 $ 314,690

Issuance of common stock and pre-funded warrants in private placement, net of issuance costs of $ 8,600

Issuance of common