UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2020 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 FOR THE TRANSITION PERIOD FROM TO Commission File Number 001-39460 KYMERA THERAPEUTICS, INC. (Exact name of Registrant as specified in its Charter) Delaware 81-2992166 (State or other jurisdiction of (I.R.S. Employer incorporation or organization) Identification No.) 200 Arsenal Yards Blvd., Suite 230 Watertown, Massachusetts 02472 (Address of principal executive offices) (Zip Code) Registrant’s telephone number, including area code: (857) 285-5300 Securities registered pursuant to Section 12(b) of the Act: Title of each class Trading Symbol(s) Name of each exchange on which registered Common Stock, par value $0.0001 per share KYMR The Nasdaq Global Market Securities registered pursuant to Section 12(g) of the Act: None Indicate by check mark if the Registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. YES ☐ NO☒ Indicate by check mark if the Registrant is not required to file reports pursuant to Section 13 or 15(d) of the Act. YES ☐ NO ☒ Indicate by check mark whether the Registrant: (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the Registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. YES ☒ NO ☐ Indicate by check mark whether the Registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the Registrant was required to submit such files). YES ☒ NO ☐ Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act. Large accelerated filer ☐ Accelerated filer ☐ Non-accelerated filer ☒ Smaller reporting company ☒ Emerging growth company ☒ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐ Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report. ☐ Indicate by check mark whether the Registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). YES ☐ NO ☒ The registrant’s common stock was not publicly traded as of the last business day of the registrant’s most recently completed second fiscal quarter. The number of shares of Registrant’s Common Stock outstanding as of February 26, 2021 was 44,811,485. DOCUMENTS INCORPORATED BY REFERENCE Portions of the registrant’s Proxy Statement for its 2021 Annual Meeting of Stockholders, which the registrant intends to file with the Securities and Exchange Commission not later than 120 days after the registrant’s fiscal year ended December 31, 2020, are incorporated by reference into Part III of this Annual Report on Form 10-K Table of Contents Page PART I Item 1. Business 3 Item 1A. Risk Factors 54 Item 1B. Unresolved Staff Comments 99 Item 2. Properties 99 Item 3. Legal Proceedings 99 Item 4. Mine Safety Disclosures 99 PART II Item 5. Market for Registrant’s Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities 100 Item 6. Selected Financial Data 100 Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations 101 Item 7A. Quantitative and Qualitative Disclosures About Market Risk 112 Item 8. Financial Statements and Supplementary Data 112 Item 9. Changes in and Disagreements With Accountants on Accounting and Financial Disclosure 113 Item 9A. Controls and Procedures 113 Item 9B. Other Information 113 PART III Item 10. Directors, Executive Officers and Corporate Governance 114 Item 11. Executive Compensation 114 Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters 114 Item 13. Certain Relationships and Related Transactions, and Director Independence 114 Item 14. Principal Accounting Fees and Services 114 PART IV Item 15. Exhibits, Financial Statement Schedules 115 Item 16 Form 10-K Summary 116 i SUMMARY OF THE MATERIAL AND OTHER RISKS ASSOCIATED WITH OUR BUSINESS • We are a biopharmaceutical company with a limited operating history and have not generated any revenue to date from drug sales, and may never become profitable. • We have incurred significant operating losses in recent periods and anticipate that we will incur continued losses for the foreseeable future. • We will need to raise substantial additional funding. If we are unable to raise capital when needed or on attractive terms, we would be forced to delay, scale back or discontinue some of our product candidate development programs or future commercialization efforts. • We are very early in our development efforts and our IRAK4, IRAKIMiD, and STAT3 programs are still in preclinical or early clinical development. If we are unable to advance them into and through the clinic for safety or efficacy reasons or commercialize our product candidates or experience significant delays in doing so, our business will be materially harmed. • Our approach to the discovery and development of product candidates based on our Pegasus platform is novel and unproven, which makes it difficult to predict the time, cost of development, and likelihood of successfully developing any products. • Business interruptions resulting from the coronavirus disease (COVID-19) outbreak or similar public health crises could cause a disruption of the development of our product candidates and adversely impact our business. • We may not be successful in our efforts to identify or discover additional product candidates or we may expend our limited resources to pursue a particular product candidate or indication and fail to capitalize on product candidates or indications that may be more profitable or for which there is a greater likelihood of success. • If we experience delays or difficulties in the initiation or enrollment of patients in clinical trials, our receipt of necessary regulatory approvals could be delayed or prevented. • Our current or future product candidates may cause adverse or other undesirable side effects that could delay or prevent their regulatory approval, limit the commercial profile of an approved label, or result in significant negative consequences following marketing approval, if any. • Even if we receive regulatory approval for any of our current or future product candidates, we will be subject to ongoing obligations and continued regulatory review, which may result in significant additional expense. • We rely, and expect to continue to rely, on third parties to conduct our ongoing and planned clinical trials for our current and future product candidates. If these third parties do not successfully carry out their contractual duties, comply with regulatory requirements or meet expected deadlines, we may not be able to obtain marketing approval for or commercialize our current and potential future product candidates and our business could be substantially harmed. • If we are unable to obtain and maintain patent and other intellectual property protection for our technology and product candidates or if the scope of the intellectual property protection obtained is not sufficiently broad, our competitors could develop and commercialize technology and drugs similar or identical to ours, and our ability to successfully commercialize our technology and drugs may be impaired. ii SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS This Annual Report on Form 10-K, or Annual Report, contains forward-looking statements which are made pursuant to the safe harbor provisions of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. All statements other than statements of historical facts contained in this Annual Report are forward- looking statements. In some cases, you can identify forward-looking statements by terminology such as “may”, “will”, “should”, “expects”, “intends”, “plans”, “anticipates”, “believes”, “estimates”, “predicts”, “potential”, “continue” or the negative of these terms or other comparable terminology. These statements are not guarantees of future results or performance and involve substantial risks and uncertainties. Forward-looking statements in this Annual Report include, but are not limited to, express or implied statements about: • the initiation, timing, progress, results, and cost of our research and development programs, and our current and future preclinical and future clinical studies, including statements regarding the timing of initiation and completion of studies or trials and related