Nature of business	12 Months Ended
Dec. 31, 2018
Nature of business
Nature of business	VOYAGER THERAPEUTICS INC. NOTES TO CONSOLIDATED FINANCIAL STATEMENTS 1. Nature of business Voyager Therapeutics, Inc. (the “Company”) is a clinical-stage gene therapy company focused on developing life-changing treatments for patients suffering from severe neurological diseases. The Company is focused on neurological diseases where it believes an adeno-associated virus (“AAV”) gene therapy approach that either increases or decreases the production of a specific protein can slow or reduce the symptoms experienced by patients, and therefore have a clinically meaningful impact. The Company has built a gene therapy platform that it believes positions itself to be a leading company at the intersection of AAV gene therapy and severe neurological disease. The Company’s gene therapy platform enables it to engineer, optimize, manufacture and deliver its AAV-based gene therapies that have the potential to provide durable efficacy following a single administration. Additionally, the Company is working to identify novel AAV capsids, which are the outer viral protein shells that enclose the genetic material of the virus payload. The Company’s team of experts in the fields of AAV gene therapy and neuroscience first identifies and selects severe neurological diseases that are well-suited for treatment using AAV gene therapy. The Company then engineers and optimizes AAV vectors for delivery of the virus payload to the targeted tissue or cells. The Company’s manufacturing process employs an established system that it believes will enable production of high quality AAV vectors at commercial-scale. In addition to the Company’s capsid optimization efforts, it leverages novel delivery paradigms, established routes of administration, and advances in dosing techniques to optimize delivery of its AAV gene therapies to target tissues, regions and cell types that are critical to the disease of interest. The Company believes it can achieve this directly, with targeted infusions to discrete regions of the brain or spinal cord, or systemically, in conjunction with its novel capsids. The Company’s business strategy focuses on discovering, developing, manufacturing and commercializing its gene therapy programs. As part of this strategy, the Company has developed core competencies specific to AAV gene therapy development and manufacturing and is beginning to build its commercial infrastructure. This business strategy also includes business development activities that may include in-licensing activities or partnering certain programs in certain geographies with collaborators, as the Company has demonstrated through its collaboration with Sanofi Genzyme (the “Sanofi Genzyme Collaboration”), its collaboration with AbbVie Biotechnology Ltd (the “AbbVie Tau Collaboration”), its collaboration with Neurocrine Biosciences, Inc. (the “Neurocrine Collaboration”), and its collaboration with AbbVie Ireland Unlimited Company (the “AbbVie Alpha-Synuclein Collaboration”). The Company is devoting substantially all of its efforts to product research and development, market development, and raising capital. The Company is subject to risks common to companies in the biotechnology and gene therapy industry, including but not limited to, the need to obtain sufficient capital to continue to fund its operations, risks of failure of preclinical studies and clinical trials, the need to obtain marketing approval for its product candidates, the need to successfully commercialize and gain market acceptance of its product candidates, dependence on key personnel, protection of proprietary technology, compliance with government regulations, development by competitors of technological innovations, and ability to transition from pilot-scale manufacturing to large-scale production of products. The Company has incurred annual net operating losses in every year since inception. As of December 31, 2018, the Company had an accumulated deficit of $269.1 million. The Company has not generated any product revenue and has financed its operations primarily through public offerings and private placements of its equity securities and funding from its collaborations with Sanofi Genzyme and AbbVie. Additionally, in January 2019, the Company entered into the Neurocrine Collaboration which is expected to commence in the first half of 2019. Under the Neurocrine Collaboration, the Company will receive an upfront payment of $165.0 million, including a $50.0 million investment in 4,179,728 shares of common stock. The effectiveness of this agreement is subject to certain conditions, including the expirations or termination of the applicable waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended, and other customary closing conditions. In February 2019, the Company announced the AbbVie Alpha-Synuclein Collaboration to develop and commercialize vectorized antibodies directed at pathological species of alpha-synuclein for the potential treatment of Parkinson’s disease and other diseases (synucleinopathies) characterized by the abnormal accumulation of misfolded alpha-synuclein protein. Under the terms of the AbbVie Alpha-Synuclein Collaboration, the Company will receive an upfront payment of $65.0 million. Based upon the current operating plan, the Company expects that its existing cash, cash equivalents, and marketable debt securities, as well as amounts expected from the upfront payment and expected reimbursement of development costs from the Neurocrine Collaboration Agreement and the upfront payment from the AbbVie Alpha-Synuclein Collaboration Agreement entered into in 2019, will enable the Company to fund its operating expenses and capital expenditure requirements into mid-2022. There can be no assurance that the Company will be able to obtain additional debt or equity financing or generate product revenue or revenue from collaborative partners on terms acceptable to the Company, on a timely basis or at all. The failure of the Company to obtain sufficient funds on acceptable terms when needed could have a material adverse effect on the Company’s business, results of operations, and financial condition.

VOYAGER THERAPEUTICS INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

1. Nature of business

Voyager Therapeutics, Inc. (the “Company”) is a clinical-stage gene therapy company focused on developing life-changing treatments for patients suffering from severe neurological diseases. The Company is focused on neurological diseases where it believes an adeno-associated virus (“AAV”) gene therapy approach that either increases or decreases the production of a specific protein can slow or reduce the symptoms experienced by patients, and therefore have a clinically meaningful impact. The Company has built a gene therapy platform that it believes positions itself to be a leading company at the intersection of AAV gene therapy and severe neurological disease. The Company’s gene therapy platform enables it to engineer, optimize, manufacture and deliver its AAV-based gene therapies that have the potential to provide durable efficacy following a single administration.

Additionally, the Company is working to identify novel AAV capsids, which are the outer viral protein shells that enclose the genetic material of the virus payload. The Company’s team of experts in the fields of AAV gene therapy and neuroscience first identifies and selects severe neurological diseases that are well-suited for treatment using AAV gene therapy. The Company then engineers and optimizes AAV vectors for delivery of the virus payload to the targeted tissue or cells. The Company’s manufacturing process employs an established system that it believes will enable production of high quality AAV vectors at commercial-scale. In addition to the Company’s capsid optimization efforts, it leverages novel delivery paradigms, established routes of administration, and advances in dosing techniques to optimize delivery of its AAV gene therapies to target tissues, regions and cell types that are critical to the disease of interest. The Company believes it can achieve this directly, with targeted infusions to discrete regions of the brain or spinal cord, or systemically, in conjunction with its novel capsids.

The Company’s business strategy focuses on discovering, developing, manufacturing and commercializing its gene therapy programs. As part of this strategy, the Company has developed core competencies specific to AAV gene therapy development and manufacturing and is beginning to build its commercial infrastructure. This business strategy also includes business development activities that may include in-licensing activities or partnering certain programs in certain geographies with collaborators, as the Company has demonstrated through its collaboration with Sanofi Genzyme (the “Sanofi Genzyme Collaboration”), its collaboration with AbbVie Biotechnology Ltd (the “AbbVie Tau Collaboration”), its collaboration with Neurocrine Biosciences, Inc. (the “Neurocrine Collaboration”), and its collaboration with AbbVie Ireland Unlimited Company (the “AbbVie Alpha-Synuclein Collaboration”). The Company is devoting substantially all of its efforts to product research and development, market development, and raising capital. The Company is subject to risks common to companies in the biotechnology and gene therapy industry, including but not limited to, the need to obtain sufficient capital to continue to fund its operations, risks of failure of preclinical studies and clinical trials, the need to obtain marketing approval for its product candidates, the need to successfully commercialize and gain market acceptance of its product candidates, dependence on key personnel, protection of proprietary technology, compliance with government regulations, development by competitors of technological innovations, and ability to transition from pilot-scale manufacturing to large-scale production of products.

The Company has incurred annual net operating losses in every year since inception. As of December 31, 2018, the Company had an accumulated deficit of $269.1 million. The Company has not generated any product revenue and has financed its operations primarily through public offerings and private placements of its equity securities and funding from its collaborations with Sanofi Genzyme and AbbVie. Additionally, in January 2019, the Company entered into the Neurocrine Collaboration which is expected to commence in the first half of 2019. Under the Neurocrine Collaboration, the Company will receive an upfront payment of $165.0 million, including a $50.0 million investment in 4,179,728 shares of common stock. The effectiveness of this agreement is subject to certain conditions, including the expirations or termination of the applicable waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended, and other customary closing conditions. In February 2019, the Company announced the AbbVie Alpha-Synuclein Collaboration to develop and commercialize vectorized antibodies directed at pathological species of alpha-synuclein for the potential treatment of Parkinson’s disease and other diseases (synucleinopathies) characterized by the abnormal accumulation of misfolded alpha-synuclein protein. Under the terms of the AbbVie Alpha-Synuclein Collaboration, the Company will receive an upfront payment of $65.0 million. Based upon the current operating plan, the Company expects that its existing cash, cash equivalents, and marketable debt securities, as well as amounts expected from the upfront payment and expected reimbursement of development costs from the Neurocrine Collaboration Agreement and the upfront payment from the AbbVie Alpha-Synuclein Collaboration Agreement entered into in 2019, will enable the Company to fund its operating expenses and capital expenditure requirements into mid-2022. There can be no assurance that the Company will be able to obtain additional debt or equity financing or generate product revenue or revenue from collaborative partners on terms acceptable to the Company, on a timely basis or at all. The failure of the Company to obtain sufficient funds on acceptable terms when needed could have a material adverse effect on the Company’s business, results of operations, and financial condition.