Kymera Therapeutics Announces Fourth Quarter and Full Year 2020 Financial Results and Provides a Business Update Initiated Phase 1 first-in-human dosing of KT-474, a first-in-class oral IRAK4 degrader to treat immune-inf

Kymera Therapeutics Announces Fourth Quarter and Full Year 2020 Financial

Results and Provides a Business Update

Initiated Phase 1 first-in-human dosing of KT-474, a first-in-class oral IRAK4 degrader to treat immune-inflammatory diseases

Declared KT-333 as STAT3 development candidate for liquid and solid tumor indications and commenced IND-enabling activities

Strong financial position to support continued execution and pipeline

growth; inaugural R&D Day to highlight five-year company vision

Watertown, Mass. (March 11, 2021) Kymera Therapeutics, Inc.

(NASDAQ: KYMR), a clinical-stage biopharmaceutical company advancing targeted protein degradation to deliver novel small molecule protein degrader medicines, today reported business highlights and financial results for the fourth quarter and full

year ended December 31, 2020.

We continue to execute against our ambitious goal to build Kymera into a fully integrated, best-in-class degrader medicines company, said Nello Mainolfi, PhD, Co-Founder, President and CEO, Kymera Therapeutics. We

have already achieved key milestones in 2021, a transformative year for Kymera and for the field of protein degradation, as we move our three lead degrader programs in immunology-inflammation and oncology into the clinic, expand our platform-enabled

pipeline of novel degraders, and continue to grow our team and build our capabilities to deliver a new class of medicines for patients.

Program Updates and Milestones

discovering and developing novel small molecule therapeutics designed to selectively degrade disease-causing proteins by harnessing the body s own natural protein degradation system, with an initial focus on immune-inflammatory diseases and

IRAK4 Degrader Program

protein involved in inflammation mediated by the activation of toll-like receptors (TLRs) and IL-1 receptors (IL-1Rs). Aberrant activation of these pathways is the

underlying cause of multiple immune-inflammatory conditions. KT-474, a potential first-in-class, highly active and selective,

orally bioavailable IRAK4 degrader, is being developed for the treatment of TLR/IL-1R-driven immune-inflammatory diseases impacting millions of patients with high unmet

medical need such as atopic dermatitis, hidradenitis suppurativa, and rheumatoid arthritis. KT-474 is designed to block

TLR/IL-1R-mediated inflammation more broadly compared to monoclonal antibodies targeting single cytokines, and to enable pathway inhibition that is superior to IRAK4

kinase inhibitors by abolishing both the kinase and scaffolding functions of IRAK4.

Expected Milestones:

IRAKIMiD Degrader Program

heterobifunctional degraders designed to degrade both IRAK4 and IMiD substrates, including Ikaros and Aiolos, with a single small molecule. IRAKIMiDs synergistically target both the

MYD88-NF-kB/MAP kinase and Type 1 interferon pathways with the potential to enhance and broaden anti-tumor activity. KT-413 is

being developed initially for the treatment of MYD88-mutant diffuse large B-cell lymphoma (DLBCL) with potential to expand in other MYD88-mutant indications and IL-1R/TLR/NF-kB-driven malignancies. In preclinical studies, KT-413 has demonstrated a potential

first-in-class profile as a targeted therapy for MYD88-mutant DLBCL, including strong single-agent antitumor activity against MYD88-mutant lymphomas in vitro and

in mouse xenograft models derived from lymphoma cell lines and patient tumors, which has led to rapid, complete, and sustained tumor regressions.

Expected Milestones:

STAT3 Degrader Program

developing selective STAT3 degraders for the treatment of hematological malignancies and solid tumors, as well as autoimmune diseases and fibrosis. STAT3 is a transcription factor activated through a variety of different cytokine and growth factor

receptors via Janus kinases (JAKs), as well as through oncogenic fusion proteins and mutations in STAT3 itself. Long considered an undruggable target, STAT3 hyperactivation is prominent in numerous liquid and solid tumors, including clinically

aggressive lymphomas. Kymera s potent and selective STAT3 degraders have demonstrated strong anti-tumor effects in mouse xenograft and syngeneic models of liquid and solid tumors.

Expected Milestones:

Platform and Discovery Programs

Kymera is also actively advancing a broad pipeline of preclinical programs across a wide variety of diseases, both internally and in collaboration with

existing partners Vertex Pharmaceuticals and Sanofi. The internal programs continue to be focused on undrugged or inadequately drugged nodes within highly validated pathways in immune-inflammatory and oncology indications. Kymera is also developing

a new generation of tissue-selective or -restrictive degrader medicines with the goal of drugging an entirely new set of protein targets.

Quarter and Full Year 2020 Financial Results

Collaboration Revenues: Collaboration revenues were $12.8 million for the fourth quarter

of 2020 and $34.0 million for the year ended December 31, 2020, compared to $1.8 million and $2.9 million, respectively, for the same periods of 2019. Collaboration revenues include revenue from our Sanofi and Vertex

collaborations in 2020, and Vertex in 2019.

Research and Development Expenses: Research and development expenses were $20.4 million for the

fourth quarter of 2020 and $62.1 million for the year ended December 31, 2020, compared to $11.1 million and $37.2 million, respectively, for the same periods of 2019. This increase was primarily due to expenses related to IND-enabling studies for our IRAK4 and IRAKIMiD programs, lead optimization activities for our STAT3 program, investments in our platform and exploratory programs, the Vertex collaboration, as well as an increase in

occupancy and related costs due to continued growth in the research and development organization.

General and Administrative Expenses: General and

administrative expenses were $5.2 million for the fourth quarter of 2020 and $18.2 million for the year ended December 31, 2020, compared to $2.5 million and $8.0 million, respectively, for the same periods of 2019. This

increase was primarily due to increases in legal and professional service fees in support of the Company s growth and an increase in personnel, facility, occupancy, and other expenses from an increase in headcount to support growth as a public

Net Loss: Net loss was $12.7 million for the fourth quarter of 2020 and $45.6 million for the year ended December 31,

2020, compared to a net loss of $11.5 million and $41.2 million, respectively, for the same periods of 2019.

Cash and Cash Equivalents: As of December 31, 2020, Kymera had approximately $458.7 million

in cash, cash equivalents, and investments. Kymera expects that its cash, cash equivalents, and investments as of December 31, 2020, excluding any future potential milestones from collaborations, will enable the Company to fund its operational

plans into 2025 while the Company continues to identify opportunities to accelerate growth and expand its pipeline, technologies, and clinical indications.

About Kymera Therapeutics

Kymera Therapeutics is

a biopharmaceutical company focused on advancing the field of targeted protein degradation, a transformative new approach to address previously intractable disease targets. Kymera s

Pegasus targeted protein degradation platform harnesses the body s natural protein recycling machinery to degrade disease-causing proteins, with a focus on undrugged nodes in validated

pathways currently inaccessible with conventional therapeutics. Kymera is accelerating drug discovery with an unmatched ability to target and degrade the most intractable of proteins, and advance new treatment options for patients. Kymera s

initial programs are IRAK4, IRAKIMiD, and STAT3, which each address high impact targets within the IL-1R/TLR or JAK/STAT pathways, providing the opportunity to treat a broad range of immune-inflammatory

diseases, hematologic malignancies, and solid tumors. For more information, visit www.kymeratx.com.

Cautionary Note Regarding

Forward-Looking Statements

This press release contains forward-looking statements within the meaning of the Private Securities Litigation

Reform Act of 1995, as amended, including, without limitation, implied and express statements regarding its: strategy, business plans and objectives for the IRAK4, IRAKIMiD and STAT3 degrader programs; and plans and timelines for the clinical

development of Kymera Therapeutics product candidates, including the therapeutic potential and clinical benefits thereof. The words may, might, will, could, would, should,

expect, plan, anticipate, intend, believe, expect, estimate, seek, predict, future, project, potential,

continue, target and similar words or expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. Any forward-looking statements in this press

release are based on management s current expectations and beliefs and are subject to a number of risks, uncertainties and important factors that may cause actual events or results to differ materially from those expressed or implied by any

forward-looking statements contained in this press release, including, without limitation, risks associated with: the impact of COVID-19 on countries or regions in which we have operations or do business, as

well as on the timing and anticipated results of our current preclinical studies and future clinical trials, strategy and future operations; the delay of any current preclinical studies or future clinical trials or the development of Kymera

Therapeutics drug candidates; the risk that the results of current preclinical studies may not be predictive of future results in connection with future clinical trials; Kymera Therapeutics ability to successfully

demonstrate the safety and efficacy of its drug candidates; the timing and outcome of the Company s planned interactions with regulatory authorities, including the resolution of the current partial clinical hold for KT-474; and obtaining, maintaining and protecting its intellectual property. These and other risks and uncertainties are described in greater detail in the section entitled Risk Factors in the

Annual Report on Form 10-K for the period ended December 31, 2020, expected to be filed on or about March 11, 2021, as well as discussions of potential risks, uncertainties, and other important

factors in Kymera Therapeutics subsequent filings with the Securities and Exchange Commission. In addition, any forward-looking statements represent Kymera Therapeutics views only as of today and should not be relied upon as representing

its views as of any subsequent date. Kymera Therapeutics explicitly disclaims any obligation to update any forward-looking statements. No representations or warranties (expressed or implied) are made about the accuracy of any such forward-looking

VP, Investor Relations and Communications

Verge Scientific Communications for Kymera

KYMERA THERAPEUTICS, INC.

CONDENSED CONSOLIDATED BALANCE SHEETS

KYMERA THERAPEUTICS, INC.

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS

(In thousands, except for share and per share amounts)