[PART I. FINANCIAL INFORMATION](index=5&type=section&id=PART%20I.%20FINANCIAL%20INFORMATION) [Item 1. Financial Statements](index=5&type=section&id=Item%201.%20Condensed%20Consolidated%20Financial%20Statements%20(Unaudited)) The unaudited financial statements show decreased assets and a significantly reduced net loss for the nine-month period Condensed Consolidated Balance Sheet Data (in thousands) | Metric | Sep 30, 2021 | Dec 31, 2020 | | :--- | :--- | :--- | | Cash and cash equivalents | $95,829 | $217,431 | | Total Assets | $230,816 | $263,737 | | Total Liabilities | $32,245 | $67,742 | | Total Stockholders' Equity | $198,571 | $195,995 | Condensed Consolidated Statements of Operations Data (in thousands) | Metric | Three Months Ended Sep 30, 2021 | Three Months Ended Sep 30, 2020 | Nine Months Ended Sep 30, 2021 | Nine Months Ended Sep 30, 2020 | | :--- | :--- | :--- | :--- | :--- | | Collaboration Revenue | $1,677 | $567 | $33,169 | $1,722 | | Research and Development | $23,987 | $20,417 | $69,439 | $77,197 | | General and Administrative | $8,351 | $8,423 | $26,054 | $24,986 | | Net Loss | $(30,608) | $(28,232) | $(62,181) | $(98,903) | | Net Loss per Share | $(0.54) | $(0.62) | $(1.14) | $(2.19) | - For the nine months ended September 30, 2021, net cash used in operating activities was **$79.3 million**, while net cash provided by financing activities was **$52.2 million**[29](index=29&type=chunk) - The company's collaboration agreement with Novartis was terminated, resulting in the recognition of approximately **$26.9 million** in collaboration revenue[102](index=102&type=chunk)[103](index=103&type=chunk) [Management's Discussion and Analysis of Financial Condition and Results of Operations](index=27&type=section&id=Item%202.%20Management's%20Discussion%20and%20Analysis%20of%20Financial%20Condition%20and%20Results%20of%20Operations) This analysis covers financial results, clinical program progress, the impact of the Novartis collaboration, and the company's liquidity position [Overview](index=27&type=section&id=Overview) - Homology Medicines is a clinical-stage company using its proprietary AAVHSC platform for in vivo gene therapy and nuclease-free gene editing[114](index=114&type=chunk) - Key clinical programs include HMI-102 for PKU gene therapy, HMI-103 for PKU gene editing, and HMI-203 for Hunter syndrome gene therapy[114](index=114&type=chunk)[121](index=121&type=chunk)[122](index=122&type=chunk) - The company operates a 25,000-square-foot GMP manufacturing facility and has produced GMP material at the 500-liter scale[116](index=116&type=chunk) - The collaboration and license agreement with Novartis was terminated, with Homology regaining worldwide exclusive rights to the remaining ophthalmic target[127](index=127&type=chunk) [Results of Operations](index=34&type=section&id=Results%20of%20Operations) Comparison of Nine Months Ended September 30, 2021 and 2020 (in thousands) | Metric | 2021 | 2020 | Change | | :--- | :--- | :--- | :--- | | Collaboration Revenue | $33,169 | $1,722 | $31,447 | | Research and Development Expenses | $69,439 | $77,197 | $(7,758) | | General and Administrative Expenses | $26,054 | $24,986 | $1,068 | | Net Loss | $(62,181) | $(98,903) | $36,722 | - Collaboration revenue for the nine months ended Sep 30, 2021, increased to **$33.2 million**, primarily due to recognizing **$28.5 million** upon Novartis's termination notice[168](index=168&type=chunk) - Research and development expenses for the nine months ended Sep 30, 2021, decreased by **$7.8 million**, mainly due to a **$12.7 million** reduction in HMI-102 external costs[169](index=169&type=chunk) [Liquidity and Capital Resources](index=39&type=section&id=Liquidity%20and%20Capital%20Resources) - As of September 30, 2021, the company had **$187.6 million** in cash, cash equivalents, and short-term investments[179](index=179&type=chunk) - Management believes existing cash will fund operations and capital expenditures into the **first quarter of 2023**[189](index=189&type=chunk) - In April 2021, the company completed a follow-on public offering, raising net proceeds of approximately **$49.7 million**[177](index=177&type=chunk) - Net cash used in operating activities for the nine months ended September 30, 2021, was **$79.3 million**, driven by the net loss and a decrease in deferred revenue[181](index=181&type=chunk) [Quantitative and Qualitative Disclosures About Market Risk](index=43&type=section&id=Item%203.%20Quantitative%20and%20Qualitative%20Disclosures%20About%20Market%20Risk) The company's primary market risk is interest rate sensitivity on its cash and investments, with no outstanding debt as of September 30, 2021 - The company's primary market risk is interest rate sensitivity related to its **$187.6 million** in cash, cash equivalents, and short-term investments[196](index=196&type=chunk) - The company had **no debt outstanding** as of September 30, 2021[196](index=196&type=chunk) [Controls and Procedures](index=43&type=section&id=Item%204.%20Controls%20and%20Procedures) Management concluded that disclosure controls and procedures were effective, with no material changes to internal controls during the quarter - Based on an evaluation as of the end of the period, the CEO and CFO concluded that the company's disclosure controls and procedures were **effective**[198](index=198&type=chunk) - There were **no material changes** in internal control over financial reporting during the quarter[199](index=199&type=chunk) [PART II. OTHER INFORMATION](index=44&type=section&id=PART%20II.%20OTHER%20INFORMATION) [Legal Proceedings](index=44&type=section&id=Item%201.%20Legal%20Proceedings) The company is not currently a party to any material legal proceedings - The company is **not party to any material legal proceedings**[201](index=201&type=chunk) [Risk Factors](index=44&type=section&id=Item%201A.%20Risk%20Factors) The company faces risks related to its history of losses, capital needs, dependence on lead candidates, and uncertainties in development and regulation [Financial and Capital Risks](index=44&type=section&id=Risks%20Related%20to%20Our%20Financial%20Position%20and%20Need%20for%20Additional%20Capital) - The company has a history of significant losses, with an accumulated deficit of approximately **$390.5 million** as of September 30, 2021[203](index=203&type=chunk) - Additional capital is required to fund operations, and failure to obtain financing could prevent the development and commercialization of product candidates[207](index=207&type=chunk) - The business is heavily dependent on the success of **HMI-102**, its most advanced product candidate[217](index=217&type=chunk) [Discovery, Development, and Regulatory Risks](index=48&type=section&id=Risks%20Related%20to%20Discovery%2C%20Development%2C%20Clinical%20Testing%2C%20Manufacturing%20and%20Regulatory%20Approval) - The company's novel genetic medicines platform makes it difficult to predict development timelines and costs[225](index=225&type=chunk) - The regulatory landscape for gene therapy and gene editing is uncertain and evolving, which could delay or prevent approval[227](index=227&type=chunk) - Clinical trials are expensive and time-consuming, and delays in patient enrollment for rare diseases could adversely affect development[233](index=233&type=chunk)[259](index=259&type=chunk) - Product candidates may cause serious adverse events, which could lead to trial halts or denial of regulatory approval[262](index=262&type=chunk) [Commercialization Risks](index=69&type=section&id=Risks%20Related%20to%20Commercialization) - The company faces significant competition from major pharmaceutical and biotechnology companies with greater financial resources[305](index=305&type=chunk)[309](index=309&type=chunk) - Successful commercialization depends on obtaining adequate coverage and reimbursement from payors, which is uncertain[311](index=311&type=chunk)[312](index=312&type=chunk) - The company lacks infrastructure for sales, marketing, and distribution and must build these capabilities or collaborate with third parties[321](index=321&type=chunk) [Intellectual Property Risks](index=76&type=section&id=Risks%20Related%20to%20Our%20Intellectual%20Property) - Success depends on obtaining and maintaining patent protection for its technology, but the patent position of biotech companies is highly uncertain[352](index=352&type=chunk)[355](index=355&type=chunk) - The company may face third-party claims of patent infringement, which could result in substantial costs or delay development[357](index=357&type=chunk) - Changes in U.S. patent laws, such as the transition to a "first-to-file" system, could diminish the value of patents[365](index=365&type=chunk)[366](index=366&type=chunk) [General Business and Employee Risks](index=85&type=section&id=Risks%20Related%20to%20Employee%20Matters%20and%20Managing%20Growth%20and%20Other%20Risks%20Related%20to%20Our%20Business) - The **COVID-19 pandemic** could adversely impact business operations, including clinical trial enrollment and supply chain[386](index=386&type=chunk)[387](index=387&type=chunk) - Future success is highly dependent on the ability to attract and retain key executive, scientific, and clinical personnel[390](index=390&type=chunk)[391](index=391&type=chunk) - As an "emerging growth company," the company is subject to reduced disclosure requirements, which may make its stock less attractive to investors[396](index=396&type=chunk) [Other Information](index=93&type=section&id=Item%205.%20Other%20Information) The company amended its lease to expand its corporate headquarters and extend the lease term to June 30, 2030 - On November 9, 2021, the company amended its lease for its corporate headquarters, expanding the premises by approximately **23,011 square feet**[416](index=416&type=chunk)[417](index=417&type=chunk) - The amendment extends the lease term for the existing premises from February 28, 2027, to **June 30, 2030**[417](index=417&type=chunk) [Exhibits](index=94&type=section&id=Item%206.%20Exhibits) This section lists all exhibits filed with the Form 10-Q, including corporate documents and officer certifications - Lists exhibits filed with the report, including corporate governance documents, the amended lease agreement, and officer certifications[421](index=421&type=chunk)

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2021 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: 001-38433 Homology Medicines, Inc. (Exact Name of Registrant as Specified in its Charter) Dela ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2021 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: 001-38433 Homology Medicines, Inc. (Exact Name of Registrant as Specified in its Charter) Del ...

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: 001-38433 Homology Medicines, Inc. (Exact name of Registrant as specified in its Charter) Delaware 47-3468154 (State or other jurisdicti ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 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: 001-38433 Homology Medicines, Inc. (Exact Name of Registrant as Specified in its Charter) ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 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: 001-38433 Homology Medicines, Inc. (Exact Name of Registrant as Specified in its Charter) Dela ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 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: 001-38433 Homology Medicines, Inc. (Exact Name of Registrant as Specified in its Charter) Del ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION For the fiscal year ended December 31, 2019 Washington, D.C. 20549 OR FORM 10-K (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 ☐ 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: 001-38433 Homology Medicines, Inc. (Exact name of Registrant as specified in its Charter) Delaware 47-3468154 (State or other jurisdicti ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2019 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: 001-38433 Homology Medicines, Inc. (Exact Name of Registrant as Specified in its Charter) ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION For the quarterly period ended June 30, 2019 WASHINGTON, DC 20549 OR FORM 10-Q ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 (Mark One) For the transition period from ___________________ to ___________________ Commission File Number: 001-38433 Homology Medicines, Inc. ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 (Exact Name of Registrant as Specified in its Charter) Dela ...