Organization and Basis of Presentation	6 Months Ended
Jun. 30, 2016
Accounting Policies [Abstract]
Organization and Basis of Presentation	1. Organization and Basis of Presentation Adverum Biotechnologies, Inc. (the “Company”, “we” or “us”) was incorporated in Delaware on July 17, 2006 as Avalanche Biotechnologies, Inc. and changed its name to Adverum Biotechnologies, Inc. on May 11, 2016. The Company is headquartered in Menlo Park, California. The Company is a gene therapy company committed to discovering and developing novel medicines that can offer potentially life-changing therapeutic benefit to patients suffering from chronic or debilitating and rare diseases. Since the Company’s inception, it has devoted its efforts principally to performing research and development activities, including conducting preclinical studies, early clinical trials, filing patent applications, obtaining regulatory approvals, hiring personnel, and raising capital to support these activities. The Company has not generated any revenue from the sale of products since its inception. The Company has experienced net losses since its inception and has an accumulated deficit of $161.2 million as of June 30, 2016. The Company expects to incur losses and have negative net cash flows from operating activities as it expands its portfolio and engages in further research and development activities. The Company believes that it has sufficient funds to continue operations for at least the next 36 months. On May 11, 2016, the acquisition closing date, the Company completed its previously announced acquisition of all the outstanding shares of Annapurna Therapeutics SAS, a French simplified joint stock company (Annapurna), in accordance with the terms of the acquisition agreement (the Agreement) dated as of January 29, 2016, as amended on April 6, 2016. As a result, Annapurna is now a wholly owned subsidiary of the Company. Pursuant to the terms of the Agreement, the Company issued 14,087,246 shares of the Company’s common stock, par value $0.0001 per share, for all of the issued and outstanding capital stock of Annapurna. All outstanding options and other rights to purchase capital stock of Annapurna were converted into the Company’s options for common stock. Refer to Note 3 for more details. Upon completion of the acquisition, the Company changed its name to “Adverum Biotechnologies, Inc.”. The Company’s shares of common stock listed on The NASDAQ Global Market, previously trading through the close of business on Wednesday, May 11, 2016 under the ticker symbol “AAVL,” commenced trading on The NASDAQ Global Market under the ticker symbol “ADVM” on Thursday, May 12, 2016. Follow-on Offerings —In January 2015, the Company completed a public offering of 2,369,375 shares of its common stock, which included 359,918 shares the Company issued pursuant to the underwriters’ exercise of their option to purchase additional shares. The Company received net proceeds of approximately $130.6 million, after underwriting discounts, commissions and offering expenses. In March 2015, (i) the Company received net proceeds of approximately $8.3 million, after discounts and other issuance costs, which resulted from the sale of 230,000 common shares, and (ii) the Company issued 230,000 common shares to a shareholder that exercised warrants prior to the initial public offering. The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (U.S. GAAP) and following the requirements of the Securities and Exchange Commission (SEC) for interim reporting. As permitted under those rules, certain footnotes or other financial information that are normally required by U.S. GAAP can be condensed or omitted. These condensed consolidated financial statements have been prepared on the same basis as the Company’s annual consolidated financial statements and, in the opinion of management, reflect all adjustments, consisting only of normal recurring adjustments, which are necessary for a fair statement of the Company’s consolidated financial information. The results of operations for the six month period ended June 30, 2016 are not necessarily indicative of the results to be expected for the full year or any other future period. The balance sheet as of December 31, 2015 has been derived from audited consolidated financial statements at that date but does not include all of the information required by U.S. GAAP for complete consolidated financial statements. The accompanying condensed consolidated financial statements and related financial information should be read in conjunction with the audited consolidated financial statements and the related notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2015 filed with the SEC.

1. Organization and Basis of Presentation

Adverum Biotechnologies, Inc. (the “Company”, “we” or “us”) was incorporated in Delaware on July 17, 2006 as Avalanche Biotechnologies, Inc. and changed its name to Adverum Biotechnologies, Inc. on May 11, 2016. The Company is headquartered in Menlo Park, California. The Company is a gene therapy company committed to discovering and developing novel medicines that can offer potentially life-changing therapeutic benefit to patients suffering from chronic or debilitating and rare diseases. Since the Company’s inception, it has devoted its efforts principally to performing research and development activities, including conducting preclinical studies, early clinical trials, filing patent applications, obtaining regulatory approvals, hiring personnel, and raising capital to support these activities.

The Company has not generated any revenue from the sale of products since its inception. The Company has experienced net losses since its inception and has an accumulated deficit of $161.2 million as of June 30, 2016. The Company expects to incur losses and have negative net cash flows from operating activities as it expands its portfolio and engages in further research and development activities. The Company believes that it has sufficient funds to continue operations for at least the next 36 months.

On May 11, 2016, the acquisition closing date, the Company completed its previously announced acquisition of all the outstanding shares of Annapurna Therapeutics SAS, a French simplified joint stock company (Annapurna), in accordance with the terms of the acquisition agreement (the Agreement) dated as of January 29, 2016, as amended on April 6, 2016. As a result, Annapurna is now a wholly owned subsidiary of the Company.

Pursuant to the terms of the Agreement, the Company issued 14,087,246 shares of the Company’s common stock, par value $0.0001 per share, for all of the issued and outstanding capital stock of Annapurna. All outstanding options and other rights to purchase capital stock of Annapurna were converted into the Company’s options for common stock. Refer to Note 3 for more details.

Upon completion of the acquisition, the Company changed its name to “Adverum Biotechnologies, Inc.”. The Company’s shares of common stock listed on The NASDAQ Global Market, previously trading through the close of business on Wednesday, May 11, 2016 under the ticker symbol “AAVL,” commenced trading on The NASDAQ Global Market under the ticker symbol “ADVM” on Thursday, May 12, 2016.

Follow-on Offerings —In January 2015, the Company completed a public offering of 2,369,375 shares of its common stock, which included 359,918 shares the Company issued pursuant to the underwriters’ exercise of their option to purchase additional shares. The Company received net proceeds of approximately $130.6 million, after underwriting discounts, commissions and offering expenses.

In March 2015, (i) the Company received net proceeds of approximately $8.3 million, after discounts and other issuance costs, which resulted from the sale of 230,000 common shares, and (ii) the Company issued 230,000 common shares to a shareholder that exercised warrants prior to the initial public offering.

The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (U.S. GAAP) and following the requirements of the Securities and Exchange Commission (SEC) for interim reporting. As permitted under those rules, certain footnotes or other financial information that are normally required by U.S. GAAP can be condensed or omitted. These condensed consolidated financial statements have been prepared on the same basis as the Company’s annual consolidated financial statements and, in the opinion of management, reflect all adjustments, consisting only of normal recurring adjustments, which are necessary for a fair statement of the Company’s consolidated financial information. The results of operations for the six month period ended June 30, 2016 are not necessarily indicative of the results to be expected for the full year or any other future period. The balance sheet as of December 31, 2015 has been derived from audited consolidated financial statements at that date but does not include all of the information required by U.S. GAAP for complete consolidated financial statements.

The accompanying condensed consolidated financial statements and related financial information should be read in conjunction with the audited consolidated financial statements and the related notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2015 filed with the SEC.