Sarepta Therapeutics (SRPT) 10-Q 5 Nov 15 2015 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2015	Oct. 30, 2015
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2015
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	Q3
Trading Symbol	SRPT
Entity Registrant Name	Sarepta Therapeutics, Inc.
Entity Central Index Key	873,303
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		45,271,301

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Current Assets:
Cash and cash equivalents	$ 55,819	$ 73,551
Short-term investments	44,090	136,793
Accounts receivable	2,733	2,416
Other current assets	19,466	35,036
Total Current Assets	122,108	247,796
Restricted cash and investments	11,478	782
Property and equipment, net of accumulated depreciation of $23,368 and $19,896 as of September 30, 2015 and December 31, 2014, respectively	37,379	38,501
Patent costs, net of accumulated amortization of $2,486 and $2,081 as of September 30, 2015 and December 31, 2014, respectively	6,116	5,891
Other assets	7,670	2,063
Total Assets	184,751	295,033
Current Liabilities:
Accounts payable	7,431	12,408
Accrued expenses	19,761	17,366
Current portion of long-term debt	3,435	98
Current portion of notes payable	2,454	2,492
Deferred revenue	3,303	3,318
Other current liabilities	1,283	1,185
Total Current Liabilities	37,667	36,867
Long-term debt	17,397	1,476
Notes payable		2,262
Deferred rent and other	6,451	6,775
Total Liabilities	$ 61,515	$ 47,380
Commitments and contingencies
Stockholders’ Equity:
Preferred stock, $.0001 par value, 3,333,333 shares authorized; none issued and outstanding
Common stock, $.0001 par value, 99,000,000 shares authorized; 41,963,151 and 41,311,512 issued and outstanding at September 30, 2015 and December 31, 2014, respectively	$ 4	$ 4
Additional paid-in capital	957,607	926,769
Accumulated other comprehensive loss	(1)	(95)
Accumulated deficit	(834,374)	(679,025)
Total Stockholders’ Equity	123,236	247,653
Total Liabilities and Stockholders’ Equity	$ 184,751	$ 295,033

Condensed Consolidated Balance3

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Statement Of Financial Position [Abstract]
Property and equipment, accumulated depreciation	$ 23,368	$ 19,896
Patent costs, accumulated amortization	$ 2,486	$ 2,081
Preferred stock, par value	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	3,333,333	3,333,333
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	99,000,000	99,000,000
Common stock, issued	41,963,151	41,311,512
Common stock, outstanding	41,963,151	41,311,512

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Income Statement [Abstract]
Revenue from research contracts and other grants		$ 1,059		$ 9,730
Operating expenses:
Research and development	$ 36,673	21,852	$ 105,018	63,399
General and administrative	15,090	12,882	50,714	35,398
Total operating expenses	51,763	34,734	155,732	98,797
Operating loss	(51,763)	(33,675)	(155,732)	(89,067)
Other income (loss):
Interest (expense) income and other, net	(176)	193	383	473
Gain (loss) on change in warrant valuation		4,256		(2,779)
Total other (loss) income	(176)	4,449	383	(2,306)
Net loss	(51,939)	(29,226)	(155,349)	(91,373)
Other comprehensive income (loss):
Unrealized gain (loss) on short-term securities - available-for-sale	18	(21)	94	(55)
Total other comprehensive income (loss)	18	(21)	94	(55)
Comprehensive loss	$ (51,921)	$ (29,247)	$ (155,255)	$ (91,428)
Net loss per share — basic and diluted	$ (1.25)	$ (0.71)	$ (3.75)	$ (2.31)
Weighted average number of shares of common stock outstanding for computing basic and diluted net loss per share	41,565	41,066	41,416	39,595

Condensed Consolidated Stateme5

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Cash flows from operating activities:
Net loss	$ (155,349)	$ (91,373)
Adjustments to reconcile net income to cash flows in operating activities:
Depreciation and amortization	3,883	2,532
Amortization of premium on available-for-sale securities and non-cash interest	805	1,848
Loss on abandonment of patents	180	52
Stock-based compensation	25,769	14,578
Increase in warrant valuation		2,779
Changes in operating assets and liabilities, net:
Net (increase) decrease in accounts receivable	(317)	168
Net decrease (increase) in other assets	9,963	(29,168)
Net decrease in accounts payable, accrued expenses, deferred revenue and other liabilities	(3,127)	(4,506)
Net cash used in operations	(118,193)	(103,090)
Cash flows from investing activities:
Release and maturity of restricted investments		3,250
Purchase of restricted investments	(10,695)
Purchase of property and equipment	(2,316)	(22,305)
Patent costs	(982)	(1,062)
Purchase of available-for-sale securities	(49,632)	(272,189)
Maturity of available-for-sale securities	141,854	86,599
Net cash from (used in) investing activities	78,229	(205,707)
Cash flows from financing activities:
Proceeds from borrowings, net of debt issuance costs	19,601
Repayments of long-term debt and notes payable	(2,573)	(70)
Proceeds from exercise of options and warrants and the sale of common stock, net of offering costs	5,204	104,201
Net cash from financing activities	22,232	104,131
Decrease in cash and cash equivalents	(17,732)	(204,666)
Cash and cash equivalents:
Beginning of period	73,551	256,965
End of period	55,819	52,299
Supplemental disclosure of cash flow information:
Cash paid during the period for interest	359	60
Supplemental schedule of non-cash investing activities and financing activities:
Accrued debt issuance costs related to the senior secured term loan	400
Property and equipment included in accrued expenses	211	1,165
Patent costs included in accrued expenses	105	187
Accrued legal and other fees for the October 9, 2015 common stock offering (See Note 11, Subsequent Event)	135
Capitalized interest	$ 99	36
Issuance of common stock in satisfaction of warrants		11,785
Tenant improvement paid by Landlord		154
Issuance of note payable in relation to the purchase of certain real and personal property located in Andover, Massachusetts		$ 4,613

BUSINESS AND BASIS OF PRESENTAT

BUSINESS AND BASIS OF PRESENTATION	9 Months Ended
	Sep. 30, 2015
Accounting Policies [Abstract]
BUSINESS AND BASIS OF PRESENTATION	1. BUSINESS AND BASIS OF PRESENTATION Business Sarepta Therapeutics, Inc. (together with its wholly-owned subsidiaries “Sarepta” or the “Company”) is a biopharmaceutical company focused on the discovery and development of unique RNA-targeted therapeutics for the treatment of rare, infectious and other diseases. Applying its proprietary, highly-differentiated and innovative platform technologies, the Company is able to target a broad range of diseases and disorders through distinct RNA-targeted mechanisms of action. The Company is primarily focused on rapidly advancing the development of its potentially disease-modifying Duchenne muscular dystrophy (“DMD”) drug candidates, including its lead DMD product candidate, eteplirsen, designed to skip exon 51. On August 25, 2015, the Company announced the filing by the Food and Drug Administration (“FDA”) of its new drug application (“NDA”) for eteplirsen for the treatment of DMD amenable to exon 51 skipping. Eteplirsen is under priority review with a Prescription Drug User Fee Act (“PDUFA”) action date of February 26, 2016. The Company is also developing therapeutics using its technology for the treatment of drug resistant bacteria and infectious, rare and other human diseases. The Company has not generated any revenue from product sales to date and there can be no assurance that revenue from product sales will be achieved. Even if it does achieve revenue from product sales, the Company is likely to continue to incur operating losses in the near term. On October 9, 2015, the Company completed a public offering whereby the Company sold 3,250,000 shares of common stock at a price of $39.00 per share. In addition, the Company granted the underwriters a 30-day option to purchase an additional 487,500 shares of common stock at a price of $39.00 per share. There can be no assurance that the underwriters will exercise the option. The Company received aggregate net proceeds from the offering of approximately $120.0 million, after deducting the underwriting discounts and offering-related transaction costs. As of September 30, 2015, the Company had approximately $111.4 million of cash, cash equivalents and investments, consisting of $55.8 million of cash and cash equivalents, $44.1 million of short-term investments and $11.5 million of restricted cash and investments. The Company believes that its balance of cash, cash equivalents and investments as of September 30, 2015, together with the net proceeds of approximately $120.0 million received from the Company’s common stock offering completed on October 9, 2015, is sufficient to fund its current operational plan for the next twelve months, though it may pursue additional cash resources through public or private financings, seek additional government contracts and establish collaborations with or license its technology to other companies. Basis of Presentation The accompanying unaudited condensed consolidated financial statements, which have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”), reflect the accounts of Sarepta Therapeutics, Inc. and its wholly-owned subsidiaries. All inter-company transactions between and among its consolidated subsidiaries have been eliminated. Management has determined that the Company operates in one segment: the development of pharmaceutical products on its own behalf or in collaboration with others. The information included in this quarterly report on Form 10-Q should be read in conjunction with the Company’s consolidated financial statements and the accompanying notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2014. Estimates and Uncertainties The preparation of the unaudited condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, equity, revenue, expenses and the disclosure of contingent assets and liabilities. Actual results could differ from those estimates. Significant items subject to such estimates and assumptions include the valuation of stock-based awards, research and development expenses, revenue recognition and income taxes.

RECENT ACCOUNTING PRONOUNCEMENT

RECENT ACCOUNTING PRONOUNCEMENTS	9 Months Ended
	Sep. 30, 2015
Accounting Changes And Error Corrections [Abstract]
RECENT ACCOUNTING PRONOUNCEMENTS	2. RECENT ACCOUNTING PRONOUNCEMENTS In April 2015, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2015-03, “Simplifying the Presentation of Debt Issuance Costs”. The amendments in this update require that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. ASU No. 2015-03 will be effective for fiscal years beginning after December 15, 2015, with early adoption permitted. The Company has elected to adopt this ASU early and the adoption of this guidance did not have a material effect on its consolidated financial statements. For additional information, please read Note 7, Long-term Debt In August 2014, the FASB issued ASU No. 2014-15, “Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern”. This update requires an entity’s management to evaluate whether there are conditions or events, considered in the aggregate, that raise substantial doubt about the entity’s ability to continue as a going concern within one year after the date that the financial statements are issued or available to be issued and to provide related disclosures. ASU No. 2014-15 is effective for the annual period ending after December 15, 2016, with early adoption permitted. The Company has not adopted this guidance as of September 30, 2015, and based on the Company's financial condition as of the date these financial statements were issued or available for issuance, the Company does not expect the adoption of this guidance to have any impact on the current period financial statements. In May 2014, the FASB issued ASU No. 2014-09, “Revenue from Contracts with Customers (Topic 606)”. This ASU supersedes the revenue recognition requirements in Accounting Standards Codification Topic 605, Revenue Recognition, Revenue from Contracts with Customers.

FAIR VALUE MEASUREMENTS

FAIR VALUE MEASUREMENTS	9 Months Ended
	Sep. 30, 2015
Fair Value Disclosures [Abstract]
FAIR VALUE MEASUREMENTS	3. FAIR VALUE MEASUREMENTS The Company has certain financial assets that are recorded at fair value which have been classified as Level 1, 2 or 3 within the fair value hierarchy as described in the accounting standards for fair value measurements. · Level 1 — quoted prices for identical instruments in active markets; · Level 2 — quoted prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active, and model-derived valuations in which all significant inputs and significant value drivers are observable in active markets; and · Level 3 — valuations derived from valuation techniques in which one or more significant value drivers are unobservable. The tables below present information about the Company’s financial assets that are measured and carried at fair value and indicate the level within the fair value hierarchy of the valuation techniques it utilizes to determine such fair value: Fair Value Measurement as of September 30, 2015 Total Level 1 Level 2 Level 3 (in thousands) Money market funds $ 140 $ 140 $ — $ — Commercial paper 11,099 — 11,099 — Government and government agency bonds 28,249 — 28,249 — Corporate bonds 15,841 — 15,841 — Certificates of deposit 11,343 11,343 — — Total assets $ 66,672 $ 11,483 $ 55,189 $ — Fair Value Measurement as of December 31, 2014 Total Level 1 Level 2 Level 3 (in thousands) Money market funds $ 47,740 $ 47,740 $ — $ — Commercial paper 2,997 — 2,997 — Government and government agency bonds 75,250 — 75,250 — Corporate bonds 58,546 — 58,546 — Certificates of deposit 647 647 — — Total assets $ 185,180 $ 48,387 $ 136,793 $ — The Company’s assets with fair value categorized as Level 1 within the fair value hierarchy include money market funds and certificates of deposit. Money market funds are publicly traded mutual funds and are presented as cash equivalents on the unaudited condensed consolidated balance sheets as of September 30, 2015. The Company’s assets with fair value categorized as Level 2 within the fair value hierarchy consist of commercial paper, government and government agency bonds and corporate bonds. These assets have been initially valued at the transaction price and subsequently valued, at the end of each reporting period, through income-based approaches utilizing observable market data. The carrying amounts reported in the unaudited condensed consolidated balance sheets for cash and cash equivalents, accounts receivable and accounts payable approximate fair value because of the immediate or short-term maturity of these financial instruments. The carrying amounts for long-term debt and notes payable approximate fair value based on market activity for other debt instruments with similar characteristics and comparable risk.

CASH, CASH EQUIVALENTS AND SHOR

CASH, CASH EQUIVALENTS AND SHORT-TERM INVESTMENTS	9 Months Ended
	Sep. 30, 2015
Cash And Cash Equivalents [Abstract]
CASH, CASH EQUIVALENTS AND SHORT-TERM INVESTMENTS	4. CASH, CASH EQUIVALENTS AND SHORT-TERM INVESTMENTS It is the Company’s policy to mitigate credit risk in its financial assets by maintaining a well-diversified portfolio that limits the amount of exposure as to maturity and investment type. The weighted average maturity of the Company’s available-for-sale securities as of September 30, 2015 and December 31, 2014 was less than 1 and 4 months, respectively. The following tables summarize the Company’s cash, cash equivalents and short-term investments for each of the periods indicated: As of September 30, 2015 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Market Value (in thousands) Cash and money market funds $ 44,720 $ — $ — $ 44,720 Commercial paper 11,099 — — 11,099 Government and government agency bonds 28,248 1 — 28,249 Corporate bonds 15,843 — (2 ) 15,841 Total assets $ 99,910 $ 1 $ (2 ) $ 99,909 As reported: Cash and cash equivalents $ 55,819 $ — $ — $ 55,819 Short-term investments 44,091 1 (2 ) 44,090 Total assets $ 99,910 $ 1 $ (2 ) $ 99,909 As of December 31, 2014 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Market Value (in thousands) Cash and money market funds $ 73,551 $ — $ — $ 73,551 Commercial paper 2,997 — — 2,997 Government and government agency bonds 75,289 — (39 ) 75,250 Corporate bonds 58,602 — (56 ) 58,546 Total assets $ 210,439 $ — $ (95 ) $ 210,344 As reported: Cash and cash equivalents $ 73,551 $ — $ — $ 73,551 Short-term investments 136,888 — (95 ) 136,793 Total assets $ 210,439 $ — $ (95 ) $ 210,344

OTHER CURRENT ASSETS

OTHER CURRENT ASSETS	9 Months Ended
	Sep. 30, 2015
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]
OTHER CURRENT ASSETS	5. OTHER CURRENT ASSETS The following table summarizes the Company’s other current assets for each of the periods indicated: As of September 30, 2015 As of December 31, 2014 (in thousands) Manufacturing-related deposits $ 14,450 $ 30,668 Prepaid expenses 4,382 2,797 Other 634 1,571 Total other current assets $ 19,466 $ 35,036

ACCRUED EXPENSES

ACCRUED EXPENSES	9 Months Ended
	Sep. 30, 2015
Payables And Accruals [Abstract]
ACCRUED EXPENSES	6. ACCRUED EXPENSES The following table summarizes the Company’s accrued expenses for each of the periods indicated: As of September 30, 2015 As of December 31, 2014 (in thousands) Accrued employee compensation costs $ 6,262 $ 6,170 Accrued clinical and preclinical costs 5,972 3,471 Accrued professional fees 3,349 3,403 Accrued contract manufacturing costs 2,145 3,271 Accrued research costs 565 311 Accrued facility-related costs 168 300 Other 1,300 440 Total accrued expenses $ 19,761 $ 17,366

LONG-TERM DEBT

LONG-TERM DEBT	9 Months Ended
	Sep. 30, 2015
Debt Disclosure [Abstract]
LONG-TERM DEBT	7. LONG-TERM DEBT On June 26, 2015, the Company entered into a credit and security agreement (the “Credit Agreement”) with MidCap Financial that provides a senior secured term loan of $20.0 million. The principal amount may be increased by an additional $20.0 million, for an aggregate amount not to exceed $40.0 million. All obligations under the Credit Agreement are secured by substantially all of the Company’s assets, excluding, without limitation, the Company’s intellectual property, certain equity interests relating to foreign subsidiaries and all assets owned by foreign subsidiaries, among others. Borrowings under the Credit Agreement bear interest at a rate per annum equal to 7.75%, with only interest payments due through June 30, 2016. In addition to paying interest on the outstanding principal under the Credit Agreement, the Company will pay an origination fee equal to 0.50% of the amount of the term loan when advanced under the Credit Agreement, as well as a final payment fee equal to 2.00% of the amount borrowed under the Credit Agreement when the term loan is fully repaid. Commencing on July 1, 2016 and continuing for the remaining twenty-four months of the facility, the Company will be required to make monthly principal payments of approximately $0.8 million, or $1.7 million if the facility is increased by the additional $20.0 million referenced above. The Company may voluntarily prepay outstanding loans under the Credit Agreement at any time, provided that the amount is not less than the total of all of the credit extensions and other related obligations under the Credit Agreement then outstanding. In the event of a voluntary prepayment, the Company is obligated to pay a prepayment fee equal to 2.95% of the outstanding principal of such advance if the prepayment is made within twelve months after the closing date, or 2.00% of the outstanding principal of such advance if the prepayment is made on or after the date that is twelve months after the closing date. The Credit Agreement contains affirmative covenants that include government compliance, reporting requirements, maintaining property, making tax payments, maintaining insurance and cooperating during litigation. Additionally, the Company is required to maintain a minimum cash balance as collateral within its operating bank account with cash and cash equivalents of no less than the greater of the outstanding principal amount or $15.0 million. Negative covenants include restrictions on asset dispositions, acquisitions, indebtedness, liens, dividends and share purchases, amendments to material contracts and other restrictions. The Credit Agreement includes customary events of default, including cross defaults, a change of control and a material adverse change. Additionally, the Company's failure to be compliant with the affirmative or negative covenants or make payments when they become due will result in an event of default. In connection with the senior secured term loan, the Company recorded $20.0 million as long-term debt in the unaudited condensed consolidated balance sheets as of September 30, 2015. In addition, the Company incurred approximately $0.8 million in debt issuance costs that were recorded as a direct deduction to the carrying value of the term loan in the unaudited condensed consolidated balance sheets. These costs are being amortized to interest expense using the effective interest method over the term of the loan. For the three and nine months ended September 30, 2015, the Company recognized $0.4 million and $0.5 million of interest expense related to the term loan, respectively. The following table summarizes the components of the long-term debt recorded for the period indicated: As of September 30, 2015 (in thousands) Principal amount $ 20,000 Unamortized debt issuance costs (668 ) Net carrying value of senior secured term loan 19,332 Other long-term debt 1,500 Total long-term debt $ 20,832

STOCK-BASED COMPENSATION

STOCK-BASED COMPENSATION	9 Months Ended
	Sep. 30, 2015
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
STOCK-BASED COMPENSATION	8. STOCK-BASED COMPENSATION The following table summarizes the Company’s stock awards granted for each of the periods indicated: For the Three Months Ended September 30, For the Nine Months Ended September 30, 2015 2014 2015 2014 Grants Weighted Average Grant Date Fair Value Grants Weighted Average Grant Date Fair Value Grants Weighted Average Grant Date Fair Value Grants Weighted Average Grant Date Fair Value Stock options* 702,067 $ 24.05 237,050 $ 16.19 2,676,778 $ 14.67 1,540,085 $ 19.24 Restricted stock awards** 65,000 $ 33.81 — $ — 181,783 $ 20.80 6,000 $ 29.03 * A majority of the stock options granted during the periods presented in the table have only service-based criteria and vest over four years. ** In September 2015, the Company granted certain employees restricted stock awards (“RSAs”) with performance conditions. If certain performance milestones are achieved within the required time frame, the number of RSAs with performance conditions may be increased from 65,000 to 97,500 shares. As a result, the Company may recognize up to $3.3 million of stock-based compensation related to these grants when performance is deemed probable. Stock-based Compensation Expense For the three months ended September 30, 2015 and 2014, total stock-based compensation expense was $5.7 million and $4.6 million, respectively. For the nine months ended September 30, 2015 and 2014, total stock-based compensation expense was $25.8 million and $14.6 million, respectively. Included in the amount for the nine months ended September 30, 2015 is $8.6 million of stock-based compensation expense incurred in connection with the resignation of the Company’s former Chief Executive Officer (“CEO”). The following table summarizes stock-based compensation expense by function included within the unaudited condensed consolidated statements of operations and comprehensive loss: For the Three Months Ended September 30, For the Nine Months Ended September 30, 2015 2014 2015 2014 (in thousands) Research and development $ 2,631 $ 1,668 $ 7,639 $ 5,886 General and administrative 3,052 2,981 18,130 8,692 Total stock-based compensation expense $ 5,683 $ 4,649 $ 25,769 $ 14,578 The following table summarizes stock-based compensation expense by grant type included within the unaudited condensed consolidated statements of operations and comprehensive loss: For the Three Months Ended September 30, For the Nine Months Ended September 30, 2015 2014 2015 2014 (in thousands) Stock options $ 4,801 $ 4,217 $ 23,451 $ 13,170 Restricted stock awards 136 33 310 169 Restricted stock units — — — 1 Stock appreciation rights 115 147 377 440 Employee stock purchase plan 631 252 1,631 798 Total stock-based compensation expense $ 5,683 $ 4,649 $ 25,769 $ 14,578

NET LOSS PER SHARE

NET LOSS PER SHARE	9 Months Ended
	Sep. 30, 2015
Earnings Per Share [Abstract]
NET LOSS PER SHARE	9. NET LOSS PER SHARE Basic net loss per share is computed by dividing net loss by the weighted-average number of shares of common stock outstanding. Diluted net loss per share is computed by dividing net loss by the weighted-average number of shares of common stock and dilutive common stock equivalents outstanding. Given that the Company generated a net loss for each of the periods presented, there is no difference between basic and diluted net loss per share since the effect of common stock equivalents would be anti-dilutive and, therefore, would be excluded from the diluted net loss per share calculation. For the Three Months Ended September 30, For the Nine Months Ended September 30, 2015 2014 2015 2014 (in thousands, except per share amounts) Net loss $ (51,939 ) $ (29,226 ) $ (155,349 ) $ (91,373 ) Weighted-average number of shares of common stock and common stock equivalents outstanding: Weighted-average number of shares of common stock outstanding for computing basic loss per share 41,565 41,066 41,416 39,595 Dilutive effect of outstanding stock awards and stock options after application of the treasury stock method* — — — — Weighted-average number of shares of common stock and dilutive common stock equivalents outstanding for computing diluted loss per share 41,565 41,066 41,416 39,595 Net loss per share — basic and diluted $ (1.25 ) $ (0.71 ) $ (3.75 ) $ (2.31 ) * For the three and nine months ended September 30, 2015 and 2014, stock options, RSAs and stock appreciation rights to purchase approximately 7.3 million and 5.3 million shares of common stock, respectively, were excluded from the net loss per share calculation as their effect would have been anti-dilutive.

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	9 Months Ended
	Sep. 30, 2015
Commitments And Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	10. COMMITMENTS AND CONTINGENCIES Purchase Commitments The following table presents non-cancelable contractual obligations arising from arrangements that the Company has entered into from time to time for the provision of goods and services: As of September 30, 2015 (in thousands) 2015 (3 months) $ 6,060 2016 57,047 2017 29,664 2018 28,521 2019 11,408 Total purchase commitments $ 132,700 In connection with an amendment to a supply agreement, in September 2015, the Company issued an irrevocable standby letter of credit totaling $10.7 million to a contract manufacturing vendor. The obligation secured by the letter of credit will be fulfilled upon full payment of all deposits and purchase payments by the end of 2016. To meet the requirement of the letter of credit, the Company purchased $10.7 million in a certificate of deposit with a September 2016 maturity date. If the commitments have not occurred as of December 31, 2016, the letter of credit will be extended. The Company has recorded this $10.7 million as restricted investments in the unaudited condensed consolidated balance sheet as of September 30, 2015. Litigation In the normal course of business, the Company may from time to time be named as a party to various legal claims, actions and complaints, including matters involving securities, employment, intellectual property, effects from the use of therapeutics utilizing its technology, or others. For example, purported class action complaints were filed against the Company and certain of its officers in the U.S. District Court for the District of Massachusetts on January 27, 2014 and January 29, 2014. The complaints were consolidated into a single action (Corban v. Sarepta, et. al., No. 14-cv-10201) Another complaint was filed in the U.S. District Court for the District of Massachusetts on December 3, 2014 by William Kader, Individually and on Behalf of All Others Similarly Situated v. Sarepta Therapeutics Inc., Christopher Garabedian, and Sandesh Mahatme (Kader v. Sarepta et.al 1:14-cv-14318) In addition, two derivative suits were filed based upon the Company’s disclosures related to eteplirsen. On February 5, 2015, a derivative suit was filed against the Company’s Board of Directors in the 215th Judicial District of Harris County, Texas (David Smith, derivatively on behalf of Sarepta Therapeutics, Inc., v. Christopher Garabedian et. al, Cause No. 2015-06645) (Ira Gaines, and the Ira J. Gaines Revocable Trust U/A, on behalf of nominal defendant Sarepta Therapeutics, Inc., vs. Goolsbee et. al., No. 10713) Additionally, on September 23, 2014, a derivative suit was filed against the Company’s Board of Directors with the Court of Chancery of the State of Delaware (Terry McDonald, derivatively on behalf of Sarepta Therapeutics, Inc., et. al vs. Goolsbee et. al., No. 10157)

SUBSEQUENT EVENT

SUBSEQUENT EVENT	9 Months Ended
	Sep. 30, 2015
Subsequent Events [Abstract]
SUBSEQUENT EVENT	11. SUBSEQUENT EVENT Subsequent events have been evaluated through the date these consolidated financial statements were filed. On October 9, 2015, the Company sold 3,250,000 shares of common stock at a price of $39.00 per share. In addition, the Company granted the underwriters a 30-day option to purchase an additional 487,500 shares of common stock at a price of $39.00 per share. There can be no assurance that the underwriters will exercise the option. The Company received aggregate net proceeds of approximately $120.0 million, after deducting the underwriting discounts and offering-related transaction costs.

BUSINESS AND BASIS OF PRESENT17

BUSINESS AND BASIS OF PRESENTATION (Policies)	9 Months Ended
	Sep. 30, 2015
Accounting Policies [Abstract]
Business	Business Sarepta Therapeutics, Inc. (together with its wholly-owned subsidiaries “Sarepta” or the “Company”) is a biopharmaceutical company focused on the discovery and development of unique RNA-targeted therapeutics for the treatment of rare, infectious and other diseases. Applying its proprietary, highly-differentiated and innovative platform technologies, the Company is able to target a broad range of diseases and disorders through distinct RNA-targeted mechanisms of action. The Company is primarily focused on rapidly advancing the development of its potentially disease-modifying Duchenne muscular dystrophy (“DMD”) drug candidates, including its lead DMD product candidate, eteplirsen, designed to skip exon 51. On August 25, 2015, the Company announced the filing by the Food and Drug Administration (“FDA”) of its new drug application (“NDA”) for eteplirsen for the treatment of DMD amenable to exon 51 skipping. Eteplirsen is under priority review with a Prescription Drug User Fee Act (“PDUFA”) action date of February 26, 2016. The Company is also developing therapeutics using its technology for the treatment of drug resistant bacteria and infectious, rare and other human diseases. The Company has not generated any revenue from product sales to date and there can be no assurance that revenue from product sales will be achieved. Even if it does achieve revenue from product sales, the Company is likely to continue to incur operating losses in the near term. On October 9, 2015, the Company completed a public offering whereby the Company sold 3,250,000 shares of common stock at a price of $39.00 per share. In addition, the Company granted the underwriters a 30-day option to purchase an additional 487,500 shares of common stock at a price of $39.00 per share. There can be no assurance that the underwriters will exercise the option. The Company received aggregate net proceeds from the offering of approximately $120.0 million, after deducting the underwriting discounts and offering-related transaction costs. As of September 30, 2015, the Company had approximately $111.4 million of cash, cash equivalents and investments, consisting of $55.8 million of cash and cash equivalents, $44.1 million of short-term investments and $11.5 million of restricted cash and investments. The Company believes that its balance of cash, cash equivalents and investments as of September 30, 2015, together with the net proceeds of approximately $120.0 million received from the Company’s common stock offering completed on October 9, 2015, is sufficient to fund its current operational plan for the next twelve months, though it may pursue additional cash resources through public or private financings, seek additional government contracts and establish collaborations with or license its technology to other companies.
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed consolidated financial statements, which have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”), reflect the accounts of Sarepta Therapeutics, Inc. and its wholly-owned subsidiaries. All inter-company transactions between and among its consolidated subsidiaries have been eliminated. Management has determined that the Company operates in one segment: the development of pharmaceutical products on its own behalf or in collaboration with others. The information included in this quarterly report on Form 10-Q should be read in conjunction with the Company’s consolidated financial statements and the accompanying notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2014.
Estimates and Uncertainties	Estimates and Uncertainties The preparation of the unaudited condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, equity, revenue, expenses and the disclosure of contingent assets and liabilities. Actual results could differ from those estimates. Significant items subject to such estimates and assumptions include the valuation of stock-based awards, research and development expenses, revenue recognition and income taxes.
Recent Accounting Pronouncements	In April 2015, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2015-03, “Simplifying the Presentation of Debt Issuance Costs”. The amendments in this update require that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. ASU No. 2015-03 will be effective for fiscal years beginning after December 15, 2015, with early adoption permitted. The Company has elected to adopt this ASU early and the adoption of this guidance did not have a material effect on its consolidated financial statements. For additional information, please read Note 7, Long-term Debt In August 2014, the FASB issued ASU No. 2014-15, “Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern”. This update requires an entity’s management to evaluate whether there are conditions or events, considered in the aggregate, that raise substantial doubt about the entity’s ability to continue as a going concern within one year after the date that the financial statements are issued or available to be issued and to provide related disclosures. ASU No. 2014-15 is effective for the annual period ending after December 15, 2016, with early adoption permitted. The Company has not adopted this guidance as of September 30, 2015, and based on the Company's financial condition as of the date these financial statements were issued or available for issuance, the Company does not expect the adoption of this guidance to have any impact on the current period financial statements. In May 2014, the FASB issued ASU No. 2014-09, “Revenue from Contracts with Customers (Topic 606)”. This ASU supersedes the revenue recognition requirements in Accounting Standards Codification Topic 605, Revenue Recognition, Revenue from Contracts with Customers.

FAIR VALUE MEASUREMENTS (Tables

FAIR VALUE MEASUREMENTS (Tables)	9 Months Ended
	Sep. 30, 2015
Fair Value Disclosures [Abstract]
Assets Measured and Carried at Fair Value	The tables below present information about the Company’s financial assets that are measured and carried at fair value and indicate the level within the fair value hierarchy of the valuation techniques it utilizes to determine such fair value: Fair Value Measurement as of September 30, 2015 Total Level 1 Level 2 Level 3 (in thousands) Money market funds $ 140 $ 140 $ — $ — Commercial paper 11,099 — 11,099 — Government and government agency bonds 28,249 — 28,249 — Corporate bonds 15,841 — 15,841 — Certificates of deposit 11,343 11,343 — — Total assets $ 66,672 $ 11,483 $ 55,189 $ — Fair Value Measurement as of December 31, 2014 Total Level 1 Level 2 Level 3 (in thousands) Money market funds $ 47,740 $ 47,740 $ — $ — Commercial paper 2,997 — 2,997 — Government and government agency bonds 75,250 — 75,250 — Corporate bonds 58,546 — 58,546 — Certificates of deposit 647 647 — — Total assets $ 185,180 $ 48,387 $ 136,793 $ —

CASH, CASH EQUIVALENTS AND SH19

CASH, CASH EQUIVALENTS AND SHORT-TERM INVESTMENTS (Tables)	9 Months Ended
	Sep. 30, 2015
Cash And Cash Equivalents [Abstract]
Summary of Company Cash, Cash Equivalents and Short-Term Investments	The following tables summarize the Company’s cash, cash equivalents and short-term investments for each of the periods indicated: As of September 30, 2015 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Market Value (in thousands) Cash and money market funds $ 44,720 $ — $ — $ 44,720 Commercial paper 11,099 — — 11,099 Government and government agency bonds 28,248 1 — 28,249 Corporate bonds 15,843 — (2 ) 15,841 Total assets $ 99,910 $ 1 $ (2 ) $ 99,909 As reported: Cash and cash equivalents $ 55,819 $ — $ — $ 55,819 Short-term investments 44,091 1 (2 ) 44,090 Total assets $ 99,910 $ 1 $ (2 ) $ 99,909 As of December 31, 2014 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Market Value (in thousands) Cash and money market funds $ 73,551 $ — $ — $ 73,551 Commercial paper 2,997 — — 2,997 Government and government agency bonds 75,289 — (39 ) 75,250 Corporate bonds 58,602 — (56 ) 58,546 Total assets $ 210,439 $ — $ (95 ) $ 210,344 As reported: Cash and cash equivalents $ 73,551 $ — $ — $ 73,551 Short-term investments 136,888 — (95 ) 136,793 Total assets $ 210,439 $ — $ (95 ) $ 210,344

OTHER CURRENT ASSETS (Tables)

OTHER CURRENT ASSETS (Tables)	9 Months Ended
	Sep. 30, 2015
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]
Summary of Other Current Assets	The following table summarizes the Company’s other current assets for each of the periods indicated: As of September 30, 2015 As of December 31, 2014 (in thousands) Manufacturing-related deposits $ 14,450 $ 30,668 Prepaid expenses 4,382 2,797 Other 634 1,571 Total other current assets $ 19,466 $ 35,036

ACCRUED EXPENSES (Tables)

ACCRUED EXPENSES (Tables)	9 Months Ended
	Sep. 30, 2015
Payables And Accruals [Abstract]
Summary of Accrued Expenses	The following table summarizes the Company’s accrued expenses for each of the periods indicated: As of September 30, 2015 As of December 31, 2014 (in thousands) Accrued employee compensation costs $ 6,262 $ 6,170 Accrued clinical and preclinical costs 5,972 3,471 Accrued professional fees 3,349 3,403 Accrued contract manufacturing costs 2,145 3,271 Accrued research costs 565 311 Accrued facility-related costs 168 300 Other 1,300 440 Total accrued expenses $ 19,761 $ 17,366

LONG-TERM DEBT (Tables)

LONG-TERM DEBT (Tables)	9 Months Ended
	Sep. 30, 2015
Debt Disclosure [Abstract]
Components of Long-Term Debt	The following table summarizes the components of the long-term debt recorded for the period indicated: As of September 30, 2015 (in thousands) Principal amount $ 20,000 Unamortized debt issuance costs (668 ) Net carrying value of senior secured term loan 19,332 Other long-term debt 1,500 Total long-term debt $ 20,832

STOCK-BASED COMPENSATION (Table

STOCK-BASED COMPENSATION (Tables)	9 Months Ended
	Sep. 30, 2015
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Summary of Stock Awards Granted	The following table summarizes the Company’s stock awards granted for each of the periods indicated: For the Three Months Ended September 30, For the Nine Months Ended September 30, 2015 2014 2015 2014 Grants Weighted Average Grant Date Fair Value Grants Weighted Average Grant Date Fair Value Grants Weighted Average Grant Date Fair Value Grants Weighted Average Grant Date Fair Value Stock options* 702,067 $ 24.05 237,050 $ 16.19 2,676,778 $ 14.67 1,540,085 $ 19.24 Restricted stock awards** 65,000 $ 33.81 — $ — 181,783 $ 20.80 6,000 $ 29.03 * A majority of the stock options granted during the periods presented in the table have only service-based criteria and vest over four years. ** In September 2015, the Company granted certain employees restricted stock awards (“RSAs”) with performance conditions. If certain performance milestones are achieved within the required time frame, the number of RSAs with performance conditions may be increased from 65,000 to 97,500 shares. As a result, the Company may recognize up to $3.3 million of stock-based compensation related to these grants when performance is deemed probable.
Summary of Stock-Based Compensation Expense by Function Included within Condensed Consolidated Statement of Operations and Comprehensive Loss	The following table summarizes stock-based compensation expense by function included within the unaudited condensed consolidated statements of operations and comprehensive loss: For the Three Months Ended September 30, For the Nine Months Ended September 30, 2015 2014 2015 2014 (in thousands) Research and development $ 2,631 $ 1,668 $ 7,639 $ 5,886 General and administrative 3,052 2,981 18,130 8,692 Total stock-based compensation expense $ 5,683 $ 4,649 $ 25,769 $ 14,578
Summary of Stock-Based Compensation Expense by Grant Type Included within Condensed Consolidated Statement of Operations and Comprehensive Loss	The following table summarizes stock-based compensation expense by grant type included within the unaudited condensed consolidated statements of operations and comprehensive loss: For the Three Months Ended September 30, For the Nine Months Ended September 30, 2015 2014 2015 2014 (in thousands) Stock options $ 4,801 $ 4,217 $ 23,451 $ 13,170 Restricted stock awards 136 33 310 169 Restricted stock units — — — 1 Stock appreciation rights 115 147 377 440 Employee stock purchase plan 631 252 1,631 798 Total stock-based compensation expense $ 5,683 $ 4,649 $ 25,769 $ 14,578

NET LOSS PER SHARE (Tables)

NET LOSS PER SHARE (Tables)	9 Months Ended
	Sep. 30, 2015
Earnings Per Share [Abstract]
Basic and Diluted Net Loss Per Share	Given that the Company generated a net loss for each of the periods presented, there is no difference between basic and diluted net loss per share since the effect of common stock equivalents would be anti-dilutive and, therefore, would be excluded from the diluted net loss per share calculation. For the Three Months Ended September 30, For the Nine Months Ended September 30, 2015 2014 2015 2014 (in thousands, except per share amounts) Net loss $ (51,939 ) $ (29,226 ) $ (155,349 ) $ (91,373 ) Weighted-average number of shares of common stock and common stock equivalents outstanding: Weighted-average number of shares of common stock outstanding for computing basic loss per share 41,565 41,066 41,416 39,595 Dilutive effect of outstanding stock awards and stock options after application of the treasury stock method* — — — — Weighted-average number of shares of common stock and dilutive common stock equivalents outstanding for computing diluted loss per share 41,565 41,066 41,416 39,595 Net loss per share — basic and diluted $ (1.25 ) $ (0.71 ) $ (3.75 ) $ (2.31 ) * For the three and nine months ended September 30, 2015 and 2014, stock options, RSAs and stock appreciation rights to purchase approximately 7.3 million and 5.3 million shares of common stock, respectively, were excluded from the net loss per share calculation as their effect would have been anti-dilutive.

COMMITMENTS AND CONTINGENCIES (

COMMITMENTS AND CONTINGENCIES (Tables)	9 Months Ended
	Sep. 30, 2015
Commitments And Contingencies Disclosure [Abstract]
Non-Cancelable Contractual Obligations	The following table presents non-cancelable contractual obligations arising from arrangements that the Company has entered into from time to time for the provision of goods and services: As of September 30, 2015 (in thousands) 2015 (3 months) $ 6,060 2016 57,047 2017 29,664 2018 28,521 2019 11,408 Total purchase commitments $ 132,700

Business and Basis of Present26

Business and Basis of Presentation - Additional Information (Detail) $ / shares in Units, $ in Thousands	Oct. 09, 2015USD ($)$ / sharesshares	Sep. 30, 2015USD ($)Segment	Dec. 31, 2014USD ($)	Sep. 30, 2014USD ($)	Dec. 31, 2013USD ($)
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Cash, cash equivalents and investments		$ 111,400
Cash and cash equivalents		55,819	$ 73,551	$ 52,299	$ 256,965
Short-term investments		44,090	136,793
Restricted cash and investments		$ 11,478	$ 782
Number of operating segments | Segment		1
Subsequent Event
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Common stock issued | shares	3,250,000
Common stock price per share | $ / shares	$ 39
Period granted to underwriters to purchase of additional shares	30 days
Common stock available for sale | shares	487,500
Net proceeds from issue of common stock	$ 120,000

Assets Measured and Carried at

Assets Measured and Carried at Fair Value (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	$ 66,672	$ 185,180
Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	140	47,740
Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	11,099	2,997
Government and Government Agency Bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	28,249	75,250
Corporate Bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	15,841	58,546
Certificates of Deposit [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	11,343	647
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	11,483	48,387
Level 1 [Member] | Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	140	47,740
Level 1 [Member] | Certificates of Deposit [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	11,343	647
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	55,189	136,793
Level 2 [Member] | Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	11,099	2,997
Level 2 [Member] | Government and Government Agency Bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	28,249	75,250
Level 2 [Member] | Corporate Bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	$ 15,841	$ 58,546

Cash, Cash Equivalents and Sh28

Cash, Cash Equivalents and Short-Term Investments - Additional Information (Detail)	9 Months Ended	12 Months Ended
	Sep. 30, 2015	Dec. 31, 2014
Maximum [Member]
Cash and Cash Equivalents [Line Items]
Weighted average maturity period of available-for-sale securities	1 month	4 months

Summary of Company Cash, Cash E

Summary of Company Cash, Cash Equivalents and Short-term Investments (Detail) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2015	Dec. 31, 2014
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents and short-term investments, Amortized cost	$ 99,910	$ 210,439
Cash, cash equivalents and short-term investments, Gross unrealized gains	1
Cash, cash equivalents and short-term investments, Gross unrealized losses	(2)	(95)
Cash, cash equivalents and short-term investments, Fair market value	99,909	210,344
Cash and Cash Equivalents [Member]
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents and short-term investments, Amortized cost	55,819	73,551
Cash, cash equivalents and short-term investments, Fair market value	55,819	73,551
Short-term Investments [Member]
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents and short-term investments, Amortized cost	44,091	136,888
Cash, cash equivalents and short-term investments, Gross unrealized gains	1
Cash, cash equivalents and short-term investments, Gross unrealized losses	(2)	(95)
Cash, cash equivalents and short-term investments, Fair market value	44,090	136,793
Cash and Money Market Funds [Member]
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents and short-term investments, Amortized cost	44,720	73,551
Cash, cash equivalents and short-term investments, Fair market value	44,720	73,551
Commercial Paper [Member]
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents and short-term investments, Amortized cost	11,099	2,997
Cash, cash equivalents and short-term investments, Fair market value	11,099	2,997
Government and Government Agency Bonds [Member]
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents and short-term investments, Amortized cost	28,248	75,289
Cash, cash equivalents and short-term investments, Gross unrealized gains	1
Cash, cash equivalents and short-term investments, Gross unrealized losses		(39)
Cash, cash equivalents and short-term investments, Fair market value	28,249	75,250
Corporate Bonds [Member]
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents and short-term investments, Amortized cost	15,843	58,602
Cash, cash equivalents and short-term investments, Gross unrealized losses	(2)	(56)
Cash, cash equivalents and short-term investments, Fair market value	$ 15,841	$ 58,546

Summary of Other Current Assets

Summary of Other Current Assets (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Prepaid Expense And Other Assets Current [Abstract]
Manufacturing-related deposits	$ 14,450	$ 30,668
Prepaid expenses	4,382	2,797
Other	634	1,571
Total other current assets	$ 19,466	$ 35,036

Summary of Accrued Expenses (De

Summary of Accrued Expenses (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Payables And Accruals [Abstract]
Accrued employee compensation costs	$ 6,262	$ 6,170
Accrued clinical and preclinical costs	5,972	3,471
Accrued professional fees	3,349	3,403
Accrued contract manufacturing costs	2,145	3,271
Accrued research costs	565	311
Accrued facility-related costs	168	300
Other	1,300	440
Total accrued expenses	$ 19,761	$ 17,366

Long-Term Debt - Additional Inf

Long-Term Debt - Additional Information (Detail) - MidCap Financial Credit Agreement [Member] - Senior Secured Term Loan [Member] - USD ($)	3 Months Ended	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2015	Jun. 26, 2015
Debt Instrument [Line Items]
Current borrowing capacity			$ 20,000,000
Additional borrowing capacity			20,000,000
Maximum borrowing capacity			$ 40,000,000
Credit Agreement interest rate per annum	7.75%	7.75%
Interest payment due date		Jun. 30, 2016
Origination fee, percentage		0.50%
Final payment fee, percentage		2.00%
Monthly principal payments commencement date		Jul. 1, 2016
Periodic principal payment frequency		Monthly
Monthly principal payments		$ 800,000
Monthly principal payments if the facility increased by additional borrowings		1,700,000
Long-term debt	$ 20,000,000	$ 20,000,000
Debt instrument prepayment fee percent within twelve months		2.95%
Debt instrument prepayment fee percent on or after twelve months		2.00%
Minimum cash balance as collateral	15,000,000	$ 15,000,000
Debt issuance costs		800,000
Maximum [Member]
Debt Instrument [Line Items]
Interest expenses on term loans	$ 400,000	$ 500,000

Long-Term Debt - Components of

Long-Term Debt - Components of Long-Term Debt (Detail) - MidCap Financial Credit Agreement [Member] $ in Thousands	Sep. 30, 2015USD ($)
Debt Instrument [Line Items]
Other long-term debt	$ 1,500
Total long-term debt	20,832
Senior Secured Term Loan [Member]
Debt Instrument [Line Items]
Principal amount	20,000
Unamortized debt issuance costs	(668)
Net carrying value of senior secured term loan	$ 19,332

Summary of Stock Awards Granted

Summary of Stock Awards Granted (Detail) - $ / shares		3 Months Ended		9 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants, Stock options	[1]	702,067	237,050	2,676,778	1,540,085
Weighted Average Grant Date Fair Value, Stock options	[1]	$ 24.05	$ 16.19	$ 14.67	$ 19.24
Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants, Restricted stock awards	[2]	65,000		181,783	6,000
Weighted Average Grant Date Fair Value, Restricted stock awards	[2]	$ 33.81		$ 20.80	$ 29.03
[1]	A majority of the stock options granted during the periods presented in the table have only service-based criteria and vest over four years.
[2]	In September 2015, the Company granted certain employees restricted stock awards (“RSAs”) with performance conditions. If certain performance milestones are achieved within the required time frame, the number of RSAs with performance conditions may be increased from 65,000 to 97,500 shares. As a result, the Company may recognize up to $3.3 million of stock-based compensation related to these grants when performance is deemed probable.

Summary of Stock Awards Grant35

Summary of Stock Awards Granted (Parenthetical) (Detail) - USD ($)		3 Months Ended		9 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation granted under plan vest period		4 years	4 years	4 years	4 years
Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock awards with performance conditions	[1]	65,000		181,783	6,000
Restricted Stock Awards [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock awards with performance conditions				97,500
Stock-based compensation related to grants		$ 3,300,000		$ 3,300,000
Restricted Stock Awards [Member] | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock awards with performance conditions				65,000
[1]	In September 2015, the Company granted certain employees restricted stock awards (“RSAs”) with performance conditions. If certain performance milestones are achieved within the required time frame, the number of RSAs with performance conditions may be increased from 65,000 to 97,500 shares. As a result, the Company may recognize up to $3.3 million of stock-based compensation related to these grants when performance is deemed probable.

Stock Based Compensation - Addi

Stock Based Compensation - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 5,683	$ 4,649	$ 25,769	$ 14,578
Former Chief Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense			$ 8,600

Summary of Stock-Based Compensa

Summary of Stock-Based Compensation Expense by Function Included within Condensed Consolidated Statement of Operations and Comprehensive Loss (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 5,683	$ 4,649	$ 25,769	$ 14,578
Research and Development Expenses [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	2,631	1,668	7,639	5,886
General and Administrative Expenses [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 3,052	$ 2,981	$ 18,130	$ 8,692

Summary of Stock-Based Compen38

Summary of Stock-Based Compensation Expense by Grant Type Included within Condensed Consolidated Statement of Operations and Comprehensive Loss (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 5,683	$ 4,649	$ 25,769	$ 14,578
Stock Options [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	4,801	4,217	23,451	13,170
Restricted Stock Awards [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	136	33	310	169
Restricted Stock Units (RSUs) [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense				1
Stock Appreciation Rights [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	115	147	377	440
Employee Stock Purchase Plan [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 631	$ 252	$ 1,631	$ 798

Basic and Diluted Net Loss Per

Basic and Diluted Net Loss Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Earnings Per Share [Abstract]
Net loss		$ (51,939)	$ (29,226)	$ (155,349)	$ (91,373)
Weighted-average number of shares of common stock and common stock equivalents outstanding:
Weighted-average number of shares of common stock outstanding for computing basic loss per share		41,565	41,066	41,416	39,595
Dilutive effect of outstanding stock awards and stock options after application of the treasury stock method	[1]
Weighted-average number of shares of common stock and dilutive common stock equivalents outstanding for computing diluted loss per share		41,565	41,066	41,416	39,595
Net loss per share — basic and diluted		$ (1.25)	$ (0.71)	$ (3.75)	$ (2.31)
[1]	For the three and nine months ended September 30, 2015 and 2014, stock options, RSAs and stock appreciation rights to purchase approximately 7.3 million and 5.3 million shares of common stock, respectively, were excluded from the net loss per share calculation as their effect would have been anti-dilutive.

Basic and Diluted Net Loss Pe40

Basic and Diluted Net Loss Per Share (Parenthetical) (Detail) - shares shares in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Earnings Per Share [Abstract]
Anti-dilutive securities excluded from computation of earning per share	7.3	5.3	7.3	5.3

Non-Cancelable Contractual Obli

Non-Cancelable Contractual Obligations (Detail) $ in Thousands	Sep. 30, 2015USD ($)
Commitments And Contingencies Disclosure [Abstract]
2015 (3 months)	$ 6,060
2,016	57,047
2,017	29,664
2,018	28,521
2,019	11,408
Total purchase commitments	$ 132,700

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) $ in Thousands	1 Months Ended	9 Months Ended
	Sep. 30, 2015USD ($)	Sep. 30, 2015USD ($)
Commitments And Contingencies Disclosure [Abstract]
Letters of credit amount issued	$ 10,700	$ 10,700
Certificate of deposit purchased	10,695	$ 10,695
Certificate of deposit maturity date		2016-09
Restricted investments	$ 10,700	$ 10,700
Number of days to amend plaintiffs complaint		28 days
Law affected under lawsuit filling		The consolidated amended complaint alleged that Sarepta and certain of its officers violated the federal securities laws in connection with disclosures related to eteplirsen

Subsequent Events - Additional

Subsequent Events - Additional Information (Detail) - Subsequent Event $ / shares in Units, $ in Millions	Oct. 09, 2015USD ($)$ / sharesshares
Subsequent Event [Line Items]
Common stock issued	3,250,000
Common stock price per share | $ / shares	$ 39
Period granted to underwriters to purchase of additional shares	30 days
Common stock available for sale	487,500
Net proceeds from issue of common stock | $	$ 120