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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORM 10-Q

(Mark One)

For the quarterly period ended September 30, 2021

OR

For the transition period from to

Commission File Number: 001-40502

Lyell Immunopharma, Inc.

(Exact Name of Registrant as Specified in its Charter)

Registrant’s telephone number, including area code: (650) 695-0677

Securities registered pursuant to Section 12(b) of the Act:

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.

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 is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No ☒

As of November 5, 2021, the registrant had 240,471,497 shares of common stock, $0.0001 par value per share, outstanding.

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SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This Quarterly Report on Form 10-Q contains forward-looking statements. All statements other than statements of historical facts contained in this Quarterly Report on Form 10-Q, including statements regarding our future results of operations and financial position, business strategy, product candidates, planned nonclinical studies and clinical trials, results of nonclinical studies, clinical trials, research and development costs, planned regulatory submissions, regulatory approvals, timing and likelihood of success, as well as plans and objectives of management for future operations, are forward-looking statements. These statements involve known and unknown risks, uncertainties and other important factors that are in some cases beyond our control and may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by the forward-looking statements.

In some cases, you can identify forward-looking statements by terms such as “may,” “will,” “should,” “would,” “expect,” “plan,” “anticipate,” “could,” “intend,” “target,” “project,” “believe,” “estimate,” “predict,” “potential,” or “continue” or the negative of these terms or other similar expressions. Forward- looking statements contained in this Quarterly Report on Form 10-Q include, but are not limited to, statements about:

• the sufficiency of our existing cash to fund our future operating expenses and capital expenditure requirements;

• the accuracy of our estimates regarding expenses, revenue opportunities, capital requirements and needs for additional financing;

• the scope, progress, results and costs of developing LYL797, LYL845 or any other product candidates we may develop, and conducting preclinical studies and clinical trials, including for LYL797 and LYL845;

• the timing and costs involved in obtaining and maintaining regulatory approval of LYL797, LYL845 or any other product candidates we may develop, and the timing or likelihood of regulatory filings and approvals, including our expectation to seek special designations for our product candidates for various diseases;

• our expectations regarding GSK’s plans for the NY-ESO-1 programs;

• our plans relating to commercializing LYL797, LYL845 or any other product candidates we may develop, if approved, including the geographic areas of focus and our ability to grow a sales force;

• the size of the market opportunity for LYL797, LYL845 or any other product candidates we may develop in each of the diseases we target;

• our reliance on third parties to conduct nonclinical research activities for LYL797, LYL845 or any other product candidates we may develop;

• the characteristics, safety, efficacy and therapeutic effects of LYL797, LYL845 or any other product candidates we may develop;

• our estimates of the number of patients in the United States who suffer from the diseases we target and the number of subjects that will enroll in our clinical trials;

• the progress and focus of our current and future clinical trials, and the reporting of data from those trials, including the timing thereof;

• the ability of our clinical trials to demonstrate the safety and efficacy of LYL797, LYL845 or any other product candidates we may develop, and other positive results;

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• the success of competing therapies that are, or may become, available;

• developments relating to our competitors and our industry, including competing product candidates and therapies;

• our plans relating to the further development and manufacturing of LYL797, LYL845 or any other product candidates we may develop, including additional indications that we may pursue;

• existing regulations and regulatory developments in the United States and other jurisdictions;

• our potential and ability to successfully manufacture and supply LYL797, LYL845 or any other product candidates we may develop for clinical trials and for commercial use, if approved;

• the rate and degree of market acceptance of LYL797, LYL845 or any other product candidates we may develop, as well as the pricing and reimbursement of LYL797, LYL845 or any other product candidates we may develop, if approved;

• our continued reliance on third parties to conduct additional clinical trials of LYL797, LYL845 or any other product candidates we may develop, and for the manufacture of our product candidates;

• the scope of protection we are able to establish and maintain for intellectual property rights, including LYL797, LYL845 or any other product candidates we may develop;

• our ability to retain the continued service of our key personnel and to identify, hire, and then retain additional qualified personnel;

• our expectations regarding the impact of the COVID-19 pandemic on our business and operations, including clinical trials, manufacturing suppliers, collaborators, use of contract research organizations (CROs) and employees;

• our expectations regarding the period during which we will qualify as an emerging growth company under the Jumpstart Our Business Startups Act of 2012 (the JOBS Act); and

• our anticipated use of our existing cash, cash equivalents and marketable securities.

We have based these forward-looking statements largely on our current expectations and projections about our business, the industry in which we operate and financial trends that we believe may affect our business, financial condition, results of operations and prospects and these forward-looking statements are not guarantees of future performance or development. These forward-looking statements speak only as of the date of this Quarterly Report on Form 10-Q and are subject to a number of risks, uncertainties and assumptions described in the section titled “Risk Factors” and elsewhere in this Quarterly Report on Form 10-Q. Because forward-looking statements are inherently subject to risks and uncertainties, some of which cannot be predicted or quantified, you should not rely on these forward-looking statements as predictions of future events. The events and circumstances reflected in our forward-looking statements may not be achieved or occur and actual results could differ materially from those projected in these forward-looking statements. Except as required by applicable law, we undertake no obligation to update or supplement any forward-looking statements publicly, or to update or supplement the reasons that actual results could differ materially from those projected in these forward-looking statements, even if new information becomes available in the future.

In addition, statements that “we believe” and similar statements reflect our beliefs and opinions on the relevant subject. These statements are based upon information available to us as of the date of this Quarterly Report on Form 10-Q, and while we believe such information forms a reasonable basis for such statements, such information may be limited or incomplete, and our statements should not be read to indicate that we have conducted an exhaustive inquiry into, or review of, all potentially available relevant information. These statements are inherently uncertain, and you are cautioned not to unduly rely upon these statements.

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PART 1. FINANCIAL INFORMATION

ITEM 1. FINANCIAL STATEMENTS

Lyell Immunopharma, Inc.

Condensed Consolidated Balance Sheets

(in thousands, except per share amounts)

(unaudited)

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

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Lyell Immunopharma, Inc.

Condensed Consolidated Statements of Operations and Comprehensive Loss

(in thousands, except per share amounts)

(unaudited)

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

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Lyell Immunopharma, Inc.

Condensed Consolidated Statements of Convertible Preferred Stock and Stockholders' Equity (Deficit)

(in thousands)

(unaudited)

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

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Lyell Immunopharma, Inc.

Condensed Consolidated Statements of Convertible Preferred Stock and Stockholders' Equity (Deficit)

(in thousands)

(unaudited)