EPIRUS Biopharmaceuticals (EPRSQ) 10-Q 10 May 16 2016 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2016	May. 09, 2016
Property and Equipment, Net
Entity Registrant Name	EPIRUS Biopharmaceuticals, Inc.
Entity Central Index Key	1,135,906
Document Type	10-Q
Document Period End Date	Mar. 31, 2016
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		26,184,349
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	Q1

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 20,865	$ 31,515
Restricted cash	1,800
Prepaids and other current assets	3,029	3,732
Total current assets	25,694	35,247
Property and equipment, net	2,695	2,073
Intangible assets, net	6,211	6,410
Goodwill	26,361	26,361
Restricted cash	124	1,924
Other assets	256	249
Total assets	61,341	72,264
Current liabilities:
Accounts payable	3,750	2,051
Accrued development costs	5,472	4,438
Accrued expenses	2,704	4,003
Short term debt, net of debt discount	14,852	14,833
Accrued purchase price liability	1,625	5,493
Deferred revenue	3,349	957
Current portion of settlement obligation	490	978
Other current liabilities	200	343
Deferred tax benefit	185	185
Total current liabilities	32,627	33,281
Deferred revenue, net of current portion	1,167	1,173
Deferred tax liability	648	648
Deferred tax benefit, net of current portion	323	369
Other non-current liabilities	410	425
Total liabilities	$ 35,175	$ 35,896
Commitments and contingencies (Note 13)
Stockholders' equity:
Preferred stock, $0.001 par value; Authorized - 5,000,000 shares, Issued and Outstanding - 0 shares at March 31, 2016 and December 31, 2015
Common stock, $0.001 par value; Authorized - 70,000,000 shares at March 31, 2016 and December 31, 2015; Issued and Outstanding - 26,184,349 and 24,377,573 shares at March 31, 2016 and December 31, 2015, respectively	$ 26	$ 24
Additional paid-in capital	181,126	175,126
Accumulated other comprehensive income (loss)	39	(23)
Accumulated deficit	(155,025)	(138,759)
Total stockholders' equity	26,166	36,368
Total liabilities and stockholders' equity	$ 61,341	$ 72,264

Condensed Consolidated Balance3

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2016	Dec. 31, 2015
Condensed Consolidated Balance Sheets
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	70,000,000	70,000,000
Common stock, shares issued	26,184,349	24,377,573
Common stock, shares outstanding	26,184,349	24,377,573

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Condensed Consolidated Statements of Operations and Comprehensive Loss
Revenue	$ 803	$ 25
Operating expenses:
Research and development	10,342	3,079
General and administrative	6,468	4,168
Total operating expenses	16,810	7,247
Loss from operations	(16,007)	(7,222)
Other income (expense):
Interest income (expense), net	(372)	(281)
Other income (expense), net	71	(30)
Total other income (expense), net	(301)	(311)
Loss before income taxes	(16,308)	(7,533)
Benefit from income taxes	42	12
Net loss	$ (16,266)	$ (7,521)
Net loss per share - basic and diluted	$ (0.66)	$ (0.39)
Weighted average number of common shares used in net loss per share calculation--basic and diluted	24,818,224	19,284,653
Foreign currency translation adjustment	$ 62
Comprehensive loss	$ (16,204)	$ (7,521)

Condensed Consolidated Stateme5

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended		63 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2016
Cash flows from operating activities:
Net loss	$ (16,266)	$ (7,521)	$ 155,025
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	287	96
Non-cash interest expense	66	133
Non-cash accretion expense	117
Stock-based compensation and vesting of restricted stock	1,999	468
Deferred rent and lease incentive activity	(15)	(6)
Deferred taxes	(46)	(46)
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	703	(360)
Other non-current assets	(7)	154
Accounts payable	1,104	175
Accrued expenses and other current liabilities	(455)	(1,399)
Other non-current liabilities		(125)
Settlement obligation	(488)
Deferred revenue	2,386	243
Net cash used in operating activities	(10,615)	(8,188)
Cash flows from investing activities:
Purchases of property and equipment	(70)
Net cash provided by investing activities	(70)
Cash flows from financing activities
Proceeds from the issuance of common stock, net of costs	18	48,027
Proceeds from the exercise of common stock options		245
Net cash used in financing activities	18	48,272
Non-cash activity
Effect of exchange rate on cash	17
Net increase (decrease) in cash and cash equivalents	(10,650)	40,084
Cash and cash equivalents - Beginning of period	31,515	21,462
Cash and cash equivalents - End of period	20,865	61,546	20,865
Supplemental disclosure of cash flow information
Issuance of common stock related to Bioceros acquisition (see Note 5)	5,000
Cash paid for interest	309	149
Cash paid for income taxes	3	$ 34
Supplemental schedule of non-cash investing and financing activities:
Amounts in accounts payable for capital expenditure	$ 595		$ 595

Organization

Organization	3 Months Ended
	Mar. 31, 2016
Organization
Organization	1. Organization EPIRUS Biopharmaceuticals, Inc. (the “Company”) is a global biopharmaceutical company focused on building biosimilar business targeting rare diseases by improving patient access through cost-effective medicines. The Company’s ability to deliver on this vision is anchored in its strong technical platform and pragmatic approach to development and commercialization. The Company is headquartered in Boston, Massachusetts, with laboratories and technical capabilities, including the Company’s proprietary CHO BC® cell line platform, in Utrecht, the Netherlands, and business operations, clinical and regulatory teams based in Zug, Switzerland. Since its inception, the Company has maintained in-house technical capabilities supported by external vendor laboratories. In September 2015, the Company acquired its primary vendor laboratory, Bioceros Holding B.V., a Netherlands company (“Bioceros”), to expand its biosimilar pipeline and to vertically integrate its product development capabilities. As a result of the acquisition, Bioceros has become the Company’s wholly-owned subsidiary, renamed Epirus Biopharmaceuticals (Netherlands) B.V. See Note 5, “Acquisition,” for additional discussion of the acquisition of Bioceros. In May 2016, the Company announced the reprioritization of its pipeline to focus exclusively on developing biosimilars for the treatment of rare diseases. This includes reallocating the Company’s resources to focus on the development of BOW080 (eculizumab; reference biologic Soliris®) for the potential treatment of ultra-rare blood disorders and BOW070 (tocilizumab; reference biologic Actemra®) for the potential treatment of an uncommon lymphoproliferative disorder known as Castleman’s disease. The Company will suspend the development of its prior lead program, BOW015 (infliximab, reference biologic Remicade®), and work to further evaluate strategic options for that program, which may include partnerships, divestitures and/or other value-generating alternatives. The Company’s decision to suspend its BOW015 program is based on cost-savings, not technical reasons, and the program remains ready to commence its planned global Phase 3 clinical study. I n connection with the matters described above, the Company also announced staff reductions of up to approximately 40% of the Company’s workforce. To date, the Company has devoted substantially all of its efforts to product research and development market research, and raising capital. The Company is subject to a number of risks similar to those of other development stage life science companies, including dependence on key individuals, competition from other companies, the need for development of commercially viable products, and the need to obtain adequate additional financing to fund the development of its product candidates. The Company is also subject to a number of risks similar to other companies in the industry, including rapid technological change, regulatory approval of products, uncertainty of market acceptance of products, competition from substitute products and larger companies, the need to obtain additional financing, compliance with government regulations, protection of proprietary technology, dependence on third parties, product liability, and dependence on key individuals. If the Company does not successfully commercialize any of its product candidates , it will be unable to generate recurring product revenue or achieve profitability. As presented in the financial statements, at March 31, 2016, the Company had cash and cash equivalents of $ 20,865 and an accumulated deficit of $155,025 . During the three months ended March 31, 2016, the Company incurred a net loss of $16, 266 . Th e Company believes that its existing cash and cash equivalents, following the staff reductions and related operational changes described above, will be sufficient to fund its current operating plan and capital expenditure requirements through the second quarter of 2016. The Company is currently evaluating options for obtaining financing to fund its operations, which it will need to accomplish in the near term. Going Concern The accompanying condensed consolidated financial statements have been prepared assuming that the Company will continue as a going concern. The Company has net losses for the period from inception (January 2011) through March 31, 2016 of $155,025 , as well as negative cash flows from operating activities. Presently, the Company does not have sufficient cash resources to meet its cash requirements for the twelve months following March 31, 2016. These factors raise substantial doubt about the Company's ability to continue as a going concern. Management is in the process of evaluating various financing alternatives for operations, as the Company will need to finance future research and development activities and general and administrative expenses through fund raising in the public or private equity markets. The condensed consolidated financial statements do not include any adjustments that may be necessary should the Company be unable to continue as a going concern. The Company’s continuation as a going concern is dependent on its ability to obtain additional financing as may be required and ultimately to attain profitability. If the Company raises additional funds through the issuance of equity, the percentage ownership of current shareholders would be reduced, and such securities might have rights, preferences or privileges senior to the common stock. Additional financing may not be available upon acceptable terms, or at all. If adequate funds are not available or are not available on acceptable terms, the Company may not be able to take advantage of prospective business endeavors or opportunities, which could significantly and materially restrict its future plans for developing its business and achieving commercial revenues. If the Company is unable to obtain the necessary capital, the Company may have to cease operations.

Basis of Presentation and Use o

Basis of Presentation and Use of Estimates	3 Months Ended
	Mar. 31, 2016
Basis of Presentation and Use of Estimates
Basis of Presentation and Use of Estimates	2. Basis of Presentation and Use of Estimates The accompanying unaudited condensed consolidated financial statements of the Company have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) for interim financial reporting and as required by Regulation S-X, Rule 10-01. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. In the opinion of management, all adjustments (including those which are normal and recurring) considered necessary for a fair presentation of the interim financial information have been included. When preparing financial statements in conformity with GAAP, the Company must make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues, expenses and related disclosures at the date of the financial statements. Actual results could differ from those estimates. Additionally, operating results for the three months ended March 31 , 201 6 are not necessarily indicative of the results that may be expected for any other interim period or for the fiscal year ending December 31, 201 6 . For further information, refer to the consolidated financial statements and footnotes included in the Company’s annual consolidated financial statements for the year ended December 31, 201 5 , which are included in the Company’s annual report on Form 10-K filed with the Securities and Exchange Commission (“SEC”) on March 28 , 201 6 .

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2016
Summary of Significant Accounting Policies
Summary of Significant Accounting Policies	3. Summary of Significant Accounting Policies In the three months ended March 31, 2016, there were no changes to the Company’s significant accounting policies identified in the Company’s most recent annual consolidated financial statements for the fiscal year ended December 31, 2015, which are included in the Company’s annual report on Form 10-K filed with the SEC on March 28, 2016. Principles of Consolidation The consolidated financial statements include the accounts of Epirus and its wholly owned subsidiaries as of March 31, 2016: EB Sub, Inc., a Delaware Corporation, Epirus Biopharmaceuticals Ltd., a United Kingdom corporation, Epirus Biopharmaceuticals (Switzerland) GmbH, a Swiss corporation, Epirus Brasil Tecnologia Ltda, a Brazilian corporation and Epirus Biopharmaceuticals (Netherlands) B.V., a Netherlands corporation. All significant intercompany balances and transactions have been eliminated in consolidation. Recent Accounting Pronouncements In November 2015, the FASB issued ASU 2015-17, “ Balance Sheet Classification of Deferred Taxes ”, which simplifies the presentation of deferred income taxes. This ASU requires that deferred tax assets and liabilities be classified as non-current in a statement of financial position. The standard is effective for public companies for fiscal years beginning after December 15, 2016, including interim periods within that reporting period. Early adoption is permitted for any interim and annual financial statements that have not yet been issued. The Company early adopted ASU 2015-17 effective December 31, 2015 on a prospective basis. Adoption of this ASU resulted in a reclassification of the net current deferred tax asset of $109 and the net current deferred tax liability of $80 to the net non-current deferred tax liability in the Company’s consolidated balance sheet as of December 31, 2015. In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842) . The new standard requires that all lessees recognize the assets and liabilities that arise from leases on the balance sheet and disclose qualitative and quantitative information about its leasing arrangements. The new standard will be effective for the Company on January 1, 2019. The Company is currently evaluating the potential impact that this standard may have on its consolidated financial statements. In March 2016, the FASB issued ASU No. 2016-06, Derivatives and Hedging (Topic 815): Contingent Put and Call Options in Debt Instruments . The new standard simplifies the embedded derivative analysis for debt instruments containing contingent call or put options by removing the requirement to assess whether a contingent event is related to interest rates or credit risks. The new standard will be effective for the Company on January 1, 2017. The adoption of this standard is not expected to have an impact on the Company’s consolidated financial statements. In March 2016, the FASB issued ASU No. 2016-09, Compensation – Stock Compensation , which amends ASC Topic 718, Compensation – Stock Compensation. The new standard identifies areas for simplification involving several aspects of accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities, an option to recognize gross stock compensation expense with actual forfeitures recognized as they occur, as well as certain classifications on the statement of cash flows. The amendments are effective for annual periods beginning after December 15, 2016, and interim periods within those annual periods. Early adoption is permitted. An entity that elects early adoption must adopt all of the amendments in the same period. The Company is currently evaluating the potential impact that ASU 2016-09 may have on the Company’s financial position or results of operations.

Business Agreements

Business Agreements	3 Months Ended
	Mar. 31, 2016
Business Agreements
Business Agreements	4. Business Agreements As noted above, in May 2016, the Company made the strategic decision to suspend the development of its prior lead program, BOW015, and will work to further evaluate strategic options for that program, which may include partnerships, divestitures and/or other value-generating alternatives. As the Company pursues this strategic review, it will also be reviewing its rights and obligations under the agreements described below. Sun Pharmaceutical Industries (formerly known as Ranbaxy Laboratories) In January 2014, the Company and Sun Pharmaceutical Industries Limited (formerly known as Ranbaxy Laboratories Limited) (“Sun”) executed a royalty-bearing and non-transferrable license agreement (“Sun License Agreement”) for BOW015 to Sun for a broad range of territories including India, selected Southeast Asian markets and North Africa. Under the terms of the Sun License Agreement, the Company and Sun agreed to pursue the commercialization of BOW015 in India and Sun received the right to sell BOW015 in the territories specified in the agreement. Sun does not have the right to manufacture BOW015. For the three months ended March 3 1 , 201 6 and 2015 , the Company recorded royalty revenue of $40 and $17 , respectively, related to commercial sales of the Company’s product, Infimab, which the Company launched with its commercialization partner Sun during the fourth quarter of 2014. As of March 31 , 20 16 , outstanding roy alty payments under the Sun agreement were $40 . Sun made an upfront payment of $500 upon the execution of the license agreement by and between the Company and Sun, dated as of January 3, 2014 and as amended from time to time (the “ Sun License Agreement”) and is obligated to pay the Company up to $1,000 if certain development and regulatory approval milestones are achieved and up to $10,000 if certain sales milestones are achieved. Under certain circumstances of uncured breach by the Company and termination of the Sun License Agreement by Sun, monetary damages of $500 would be due to Sun. The Company has invoiced Sun for a total of $ 1,375 in milestone payments, including the upfront payment, and received payments totaling $1,250 through March 31 , 201 6 . Mabxience, S.A. On May 13, 2015, the Company entered into an Exclusive License Agreement (the “MabX Agreement”) with mAbxience S.A., a company organized and existing under the laws of Uruguay and a wholly owned subsidiary of CHEMO Group (“Mabxience”), for the development, manufacturing and commercialization of BOW015. Under the MabX Agreement, the Company licensed to Mabxience an exclusive, royalty-bearing, non-transferable, sublicenseable license to develop, manufacture, commercialize and distribute BOW015 in the Mabxience territory. The Mabxience territory consists of Argentina, Chile, Ecuador, Paraguay, Uruguay and Venezuela. Pursuant to the MabX Agreement, Mabxience will be solely responsible, at its expense, for all aspects of commercialization of licensed product in the Mabxience territory. As consideration for the license granted to Mabxience, the Company is eligible to receive certain non-refundable, non-creditable milestone payments up to $1,500 upon the achievement of certain commercial sales in the Mabxience territory. Specifically, the Company will earn $250 upon the first commercial sale for each first commercial sale in each of the territory countries. In addition, the Company is eligible to receive certain royalty payments in the high teen percentages and distribution payments from Mabxience. These potential milestone and royalty payments have not been earned as of March 31, 2016. Unless terminated earlier in accordance with the terms of the agreement or extended by mutual agreement of the parties, the MabX Agreement expires 15 years following the first commercial sale of BOW015 in the Mabxience territory. Polpharma On July 13, 2015, the Company entered into a Collaboration Agreement (the “ Polpharma Collaboration Agreement”) with Swiss Pharma International AG, an affiliate of Pharmaceutical Works Polpharma S.A. (together with Swiss Pharma International AG, “Polpharma”), for the development and commercialization in certain designated territories of the Company’s product candidates, BOW015, BOW050 and BOW070. The designated territories include the European Union (with the exception of Austria, Belgium, Denmark, Finland, Luxembourg, the Netherlands and Sweden, which are reserved for the Company), together with certain countries in the Middle East, Turkey, Russia, and other countries comprising the Commonwealth of Independent States, or CIS. The Company will also retain exclusive rights for the three products in North America and other markets outside of the designated territories, including Switzerland and Norway . Within the designated territories, the Polpharma Collaboration Agreement contains exclusivity provisions such that each of the Company and Polpharma agrees not to exploit any other biosimilar product based on reference product other than the three products licensed under the Polpharma Collaboration Agreement, subject to limited exceptions. The Polpharma Collaboration Agreement provides that Polpharma would bear 51% and the Company would bear 49% of total costs associated with the development programs for the three products in the designated territories. For clinical trial costs incurred in connection with global development, the cost sharing ratio is changed from 100% to 38% of total costs. As a result, under the agreement, Polpharma would bear 19% and the Company would bear 81% of total clinical trial costs incurred. Following commercial launch, profits and losses for the three products in the designated territories would be split 51% for Polpharma and 49% for the Company. For the three month period ended March 31, 2016, the Company recorded revenue of $570 related to this agreement. The Company invoiced and received a payment in the amount of $2,309 from Polpharma in January 2016. As of March 31, 2016, the Company had a deferred revenue balance of $2,263 related to the payment received for services that will be performed in future quarters of 2016. Livzon Mabpharm On September 24, 2015, the Company entered into a New Collaboration Compound Supplement to the Collaboration Agreement (the “Supplement Agreement”) with Livzon Mabpharm Inc. (“Livzon”). The Supplement Agreement amends the Exclusive License and Collaboration Agreement, dated as of September 24, 2014, by and between the Company and Livzon (the “ Livzon Collaboration Agreement”), to add the Company’s product candidate, BOW070, a biosimilar version of Actemra ® (tocilizumab), as one of the additional compounds to be developed and commercialized pursuant to the terms of the Livzon Collaboration Agreement. The Company will pay a total of $4,500 to Livzon to complete the pre-clinical development activities, consisting of: (i) an initial cash payment of $1,500 within 10 days of entry into the Livzon Supplement Agreement, which amount was paid on October 10, 2015, and (ii) three additional cash payments of $1,000 each upon the achievement of certain pre-clinical development milestones. The Company is expensing costs under the Supplement Agreement, as incurred, over the period that the work is performed (currently estimated at 18 months). For the three month period ended March 31, 2016, the Company recorded expense of $500 under the Livzon Supplement Agreement. Each of the parties is eligible to receive from t he other party royalty payments, based on gross margin of BOW070 in the other party’s territory, ranging from the low- to mid-single digit percentages. As of March 31, 2016, Livzon owned approximately 6% of the Company’s issued and outstanding common stock.

Acquisition

Acquisition	3 Months Ended
	Mar. 31, 2016
Acquisition
Acquisition	5. Acquisition On September 9, 2015, the Company entered into a stock purchase agreement (the “Stock Purchase Agreement”) whereby it acquired 100% of the voting interests of Bioceros Holding B.V. (“Bioceros”), enabling the Company to expand its biosimilar pipeline and vertically integrate product development capabilities. The Company paid a total of $14,100 in consideration consisting of: (i) an initial cash payment of $3,400 at closing, (ii) a second cash payment of $1,700 , to be paid on the first anniversary of the closing date , (iii) an initial issuance of 788,960 shares of the Company’s common stock, $0.001 par value per share (the “Common Stock”), with a value of $4,000 using a 10 day pre-closing date average price for issuance of $5.07 (value of $4,568 on acquisition date) and (iv) a second issuance of shares of Common Stock with a value of $5,000 , calculated based on the Company’s stock price as set forth in the Stock Purchase Agreement, issued on the date that was six months after the closing date (“Second Installment Shares”) , subject to the Company’s setoff rights with regard to the second cash payment and Second Installment Shares. Of the Second Installment Shares, shares with an undiscounted value of $1,015 were to be issued to Bioceros key employees. In addition, the shareholders of Bioceros would receive a pro rata share of a net cash payout equal to the aggregate amount of: (a) Bioceros’ net working capital as the acquisition date; plus (b) revenue agreements signed from select Bioceros customers subsequent to the acquisition date and through December 31, 2015; in excess of (c) $1,200 , calculated as set forth in the Stock Purchase Agreement. As of September 9, 2015, the Company estimated this amount to be $409 . As of December 31, 2015, the Company evaluated the net cash payout liability of $409 and reduced the fair value to $0 . This reduction was recorded as a credit to general and administrative expenses in the Company’s consolidated statement of operations for the fiscal year ended December 31, 2015. On March 9, 2016, the Company issued 1,772,107 shares of Common Stock using a 10 day pre-closing date average price of $2.82 for the Second Installment Shares. Second Installment Shares As described above, shares with an undiscounted value of $1,015 from t he Second Installment Shares were to be issued to Bioceros key employees and are subject to those employees’ continued employment. Pursuant to the Stock Purchase Agreement, 75% of the shares to be issued to Bioceros key employees on March 9, 2016 in connection with the Second Installment Shares will be held in an escrow account and released in three equal installments 12 , 18 and 24 months after the closing date, unless the employee is terminated for cause or voluntarily resigns prior to each release date. As a result, the consideration related to such $1,015 of shares was determined to be attributable to post-combination service to Epirus and will be recognized as stock-based compensation expense by the combined company as the shares vest. On March 8, 2016, the Company entered into the First Amendment to the Stock Purchase Agreement between the Company and seller representatives of Bioceros (the “First Amendment”). The First Amendment removes any future employment requirements of Bioceros key employees to receive the Second Installment Shares, removes the lock-up period for the Second Installment Shares and updates the maximum equity consideration to be issued pursuant to the Stock Purchase Agreement from 10% to 19.99% of the aggregate number of the Company’s total shares outstanding on the date preceding the date of the Stock Purchase Agreement. The Company recognized $889 of stock-based compensation expense related to the Second Installment Shares for the key employees in the consolidated statement of operations and comprehensive loss for the three months ended March 31, 2016 . The acquisition-date fair value of the consideration transferred is as follows: Initial equity consideration paid at closing Initial shares issued to Bioceros shareholders Price per Epirus share at issuance $ $ Initial cash consideration paid at closing Total consideration paid at closing Settlement of preexisting Epirus accounts payable to Bioceros (1) Second Installment Shares, excluding key employee stock compensation expense (2) Net cash payout (3) Final payment of cash consideration (4) Preliminary estimated purchase price $ (1) Represents the settlement of preexisting accounts payable to Bioceros as a result of activity prior to the transaction . (2) Represents the fair value of the undiscounted $3,985 of Second Installment Shares to be paid and issued on March 9, 2016, which excludes the undiscounted $1,015 of shares to be issued to Bioceros key employees contingent upon the delivery of postcombination service to the Company, as described above. This amount has been recorded as a liability on the Company’s consolidated balance sheet, because it represents an obligation to issue a variable number of shares based on a fixed dollar amount of $3,985 , and recorded at fair value utilizing a discount rate of 10.7% . (3) Represents the fair value of the net cash payout to be made pursuant to the Stock Purchase Agreement. This amount has been recorded as a contingent consideration liability on the Company’s consolidated balance sheet as of September 9, 2015 and recorded at fair value utilizing a discount rate of 10.7% . The amount of the net cash payout is dependent on revenue agreements signed from select Bioceros customers subsequent to the acquisition date and through December 31, 2015 . (4) Represents the fair value of the final cash payment of $1,700 , which, pursuant to the Stock Purchase Agreement, the Company will pay on September 9, 2016. This amount has been recorded as a liability on the Company’s consolidated balance sheet as of September 9, 201 5 and recorded at fair value utilizing a discount rate of 10.7% . The following table summarizes the preliminary estimated fair values of the assets acquired and liabilities assumed at the date of acquisition: (in thousands) Cash and cash equivalents $ Deferred tax assets Accounts receivable Prepaid expenses and other current assets Property and equipment, net Intangible assets, net Goodwill Accounts payable Accrued expenses and other current liabilities Deferred revenue Deferred tax liabilities Net assets acquired $ The purchase price allocation has been prepared on a preliminary basis and is subject to change as additional information becomes available concerning the fair value and tax basis of the assets acquired and the liabilities assumed. The purchase price allocation will remain preliminary until Epirus completes a final valuation of the assets acquired and liabilities assumed, including deferred tax assets and liabilities, deferred revenue and the identification and valuation of all intangible assets, as of the transaction closing date. The excess of consideration transferred over the estimated fair value of net identifiable assets acquired will be allocated to goodwill, which represents the expected synergies between the companies and acquired workforce. Goodwill is not expected to be deductible for tax purposes. The final determination of the allocation of consideration transferred is expected to be completed as soon as practicable, but will in no event exceed one year from September 9, 2015, the closing date. The final amounts allocated to assets acquired and liabilities assumed could differ significantly fro m the amounts presented above.

Goodwill and Intangible Assets,

Goodwill and Intangible Assets, Net	3 Months Ended
	Mar. 31, 2016
Goodwill and Intangible Assets, Net
Goodwill and Intangible Assets, Net	6 . Goodwill and Intangible Assets, Net Goodwill The Company’s goodwill balance as of March 31 , 201 6 was $26,361 . As of March 31 , 201 6 , there were no accumulated impairment losses. Goodwill has been assigned to the Company’s single reporting unit, which is the single operating segment by which the chief operating decision maker manages the Company. Intangibles Intangible assets, net of accumulated amortization is as follows: March 31, 2016 December 31, 2015 Intangible assets (excluding IPR&D) $ $ Less: accumulated amortization—intangible assets Intangible assets, net (excluding IPR&D) $ $ Amortization expense, which is included within research and development expense in the consolidated statements of operations and comprehensive loss, was $199 for the three months ended March 31 , 201 6 and $57 for the three months ended March 31 , 201 5 . The weighted average amortization period for intangible assets i s 11.6 years. The estimated aggregate amortization of intangible assets as of March 31, 2016, for each of the five succeeding years and thereafter is as follows: March 31, 2016 April 1, 2016 - December 31, 2016 $ 2017 2018 2019 2020 2021 and thereafter Total $

Accrued Expenses

Accrued Expenses	3 Months Ended
	Mar. 31, 2016
Accrued Expenses
Accrued Expenses	7 . Accrued Expenses Accrued expenses consisted of the following: March 31, 2016 December 31, 2015 Accrued compensation $ $ Accrued professional fees Accrued interest expense Other Total accrued expenses $ $

Debt

Debt	3 Months Ended
	Mar. 31, 2016
Debt
Debt	8 . Debt Hercules Notes As of March 31, 2016, the Company had outstanding borrowings under the Loan Agreement of $15,000 . Due to the going concern opinion issued as of December 31, 2015 and the fact that the Note may be declared immediately due by Hercules, upon the occurrence of a material adverse change in the Company’s business or other events of default under the Loan Agreement, the Company has recorded all amounts due under the Note as a short-term debt obligation. As of March 31, 2016, the short-term debt obligation was $14,852 , net of a debt discount of $148 . Amortization of the debt discount, which was recorded as interest expense in the statement of operations, was approximately $19 and $16 for the three months ended March 31, 2016 and March 31, 2015, respectively. Future principal payments, which exclude the 3% end of term charge that will be payable upon repayment of the notes in full, in connection with th e Loan Agreement, as of March 31, 201 6 are as follows: Principal Payments April 1, 2016 - December 31, 2016 $ 2017 2018 Total $

Capital Stock

Capital Stock	3 Months Ended
	Mar. 31, 2016
Capital Stock
Capital Stock	9 . Capital Stock On February 29, 2016, the Company entered into an At-the-Market Sales Agreement (the “Sales Agreement”) with BTIG, LLC (“BTIG”), pursuant to which the Company may sell at its option from time to time up to an aggregate of $30 million in shares of the Company’s common stock, through BTIG, as sales agent (the “Offering”). Sales of the common stock made pursuant to the Sales Agreement, if any, will be made under the Company’s previously filed and currently effective Registration Statement on Form S-3 (File No. 333-205420) and a related prospectus supplement. The Company will pay BTIG a commission equal to 3% of the gross proceeds from the sale of shares of common stock under the Sales Agreement, if any. Pursuant to the terms of the Sales Agreement, the Company also provided BTIG with customary indemnification rights. The Company has also agreed to reimburse BTIG for its reasonable out-of-pocket expenses, including the fees and disbursements of counsel to BTIG, incurred in connection with the Offering. The Company intends to use the net proceeds from the Offering for general corporate purposes, which may include research and development expenditures, clinical trial expenditures, commercialization activities and working capital. As of April 28, 2016, proceeds under this Sales Agreement have not been material. On March 9, 2016 the Company issued 1,772,107 shar es of its common stock to former holders of Bioceros preferred and common stock in connection with the acquisition of Bioceros (see Note 5).

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2016
Fair Value Measurements
Fair Value Measurements	1 0 . Fair Value Measurements The following table summarizes the financial assets and liabilities measured at fair value on a recurring basis in the accompanying balance sheets as of March 31, 2016 and December 31, 2015: As of March 31, 2016 Level 1 Level 2 Level 3 Total Assets Cash and cash equivalents $ $ — $ — $ $ $ — $ — $ As of December 31, 2015 Level 1 Level 2 Level 3 Total Assets Cash and cash equivalents $ $ — $ — $ $ $ — $ — $ As of March 3 1 , 201 6 , the Company did not have any liabilities measured at fair value on a recur ring basis.

Stock-Based Compensation

Stock-Based Compensation	3 Months Ended
	Mar. 31, 2016
Stock-Based Compensation
Stock-Based Compensation	1 1 . Stock-Based Compensation On April 2, 2015, the board of directors of the Company adopted the 2015 Equity Incentive Plan (“2015 Plan”) and on June 4, 2015, the stockholders of the Company approved the 2015 Plan. Pursuant to the 2015 Plan, 1,700,000 shares of common stock were initially authorized for issuance. On March 29, 2016, the Company increased the shares of common stock authorized issuance under the 2015 Plan by 975,102 as a result of an automatic annual increase effective as of January 1, 2016. The 2015 Plan provides for the grant of incentive stock options, nonstatutory stock options, stock appreciation rights, restricted and unrestricted stock and stock units, performance awards, cash-based awards and awards that are convertible into or otherwise based on the Company's common stock. As of March 31, 2016, the Company had 1,401,244 shares of common stock available for issuance under the 2015 Plan. For the three months ended March 31, 2016, the Company recognized stock-based compensation expense of approximately $ 1,999 in connection with its stock-based payment awards, including $889 related to key employees of Bioceros (see Note 5). For the three months ended March 31, 2015, the Company recognized stock-based compensation expense of approximately $526 in connection with its stock-based payment awards. The Company also recorded a reduction in stock-based compensation expense for the three months ended March 31, 2015 of $100 resulting from the modification of an award for a former officer of the Company. Stock Options A summary of stock option activity during the three months ended March 31, 2016 is as follows: Weighted- Average Weighted- Remaining Average Contractual Aggregate Number Exercise Term Intrinsic of Options Price (in years) Value Outstanding at December 31, 2015 $ Granted Exercised — — Cancelled Outstanding at March 31, 2016 $ $ Vested and expected to vest at March 31, 2016 $ $ Exercisable at March 31, 2016 $ $ Weighted average grant-date fair value of options granted during the period $ Cash received upon exercise of options $ — The aggregate intrinsic value in the table above represents the value (the difference between the Company’s common stock fair value on March 31, 2016 and the exercise price of the options, multiplied by the number of in-the-money options) that would have been received by the option holders had all option holders exercised their options on March 31, 2016. As of March 31, 2016, there was $ 10,025 of total unrecognized stock-based compensation expense related to stock options granted under the plans. The expense is expected to be recognized over a weighted-average period of 2.9 years. During the three months ended March 31, 2016 and 2015, the range of assumptions used in the Black-Scholes pricing model for new grants were as follows: Three Months Ended March 31, 2016 2015 Risk-free interest rate 1.35% -1.82% Expected volatility 61.40% -62.53% Expected term (in years) Expected dividend yield Restricted Stock Units A summary of the activity of nonvested restricted stock units (“RSUs”) for the nine months ended March 31, 2016 is as follows: Weighted- Average Number Weighted- Remaining of Average Contractual Aggregate Restricted Grant Date Term Intrinsic Stock Units Fair Value (in years) Value Nonvested at December 31, 2015 $ $ Granted — — — — Vested — — Cancelled — — Nonvested at March 31, 2016 $ $ Vested and expected to vest at: March 31, 2016 $ $ Exercisable at: March 31, 2016 — $ — — $ — As of March 31, 2016, there was $872 of total unrecognized stock-based compensation expense related to nonvested RSUs. The expense is expected to be recognized over a weighted-average period of 2.9 years. During February 2015, the Company issued 117,131 RSUs to certain employees, which vest with respect to one quarter (1/4) of the RSUs on the first anniversary of the grant date and an additional one quarter (1/4) on each anniversary thereafter until the fourth anniversary of the grant date. In addition, the Company issued 9,490 RSUs to certain employees as merit grants in lieu of annual raises. These RSUs vest in full on the first year anniversary of the grant date. Employee Stock Purchase Plan The Company has an Employee Stock Purchase Plan (“ESPP”) that permits eligible employees to enroll in a six-month offering period. Participants may purchase shares of the Company’s Common Stock, through payroll deductions, at a price equal to 85% of the fair market value of the Common Stock on the first day of the applicable six-month offering period, or the last day of the applicable six-month offering period, whichever is lower. Purchase dates under the ESPP occur on or about June 1 and December 1 of each year. On March 29, 2016, the Company increased the shares of common stock under the ESPP by 120,000 as a result of an automatic annual increase. As of March 31, 2016, 472,722 shares of the Company’s Common Stock remain available for issuance under the ESPP.

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2016
Income Taxes
Income Taxes	1 2 . Income Taxes For the three months ended March 31, 2016, the Company recorded an income tax benefit of $42, which is due p rimarily to the amortization of the Company’s deferred tax benefit related to the transfer of IPR&D to the Company’s subsidiary, Epirus Switzerland GmbH, a Swiss corporation (the “Tax Benefit”) of $46 , offset by tax expense for cash flows generated in foreign territories of $4 . For the three months ended March 31, 2015, the Company recorded an income tax benefit of $ 12 , which is due primarily to the Tax Benefit of $46 , offset by tax expense for cash flows generated in foreign territories of $27 and minimum state taxes due in the United States of $7 . The Company has evaluated the positive and negative evidence on the realizability of its deferred tax assets in each jurisdiction and management has determined that it is more likely than not that the Company will not utilize the benefits of its deferred tax assets in each jurisdiction except the Netherlands. Accordingly, the deferred tax assets have been fully reserved as of March 31, 2016 and December 31, 2015.

Commitments

Commitments	3 Months Ended
	Mar. 31, 2016
Commitments
Commitments	1 3 . Commitments As of March 31, 2016, future minimum lease payments under all of the Company’s operating leases are as follows: March 31, 2016 April 1, 2016 - December 31, 2016 $ 2017 2018 2019 2020 2021 and thereafter Total $ Less: Future sublease payments to be received Net future lease payments $

Legal Proceedings

Legal Proceedings	3 Months Ended
	Mar. 31, 2016
Legal Proceedings
Legal Proceedings	15 Legal Proceedings From time to time, the Company is involved in legal proceedings and claims of various types and accounts for these legal proceedings in accordance with ASC Topic 450, “Contingencies.” The Company records a liability in its consolidated financial statements for these matters when a loss is considered probable and the amount of loss can be reasonably estimated. The Company reviews these estimates each accounting period as additional information is known and adjusts the loss provision when appropriate. If the loss is not probable or cannot be reasonably estimated, a liability is not recorded in its consolidated financial statements. Reliance Life Sciences Dispute In December 2014, Reliance Life Sciences Pvt Ltd, or RLS, the Company’s BOW015 contract manufacturer for India, exercised its three -year termination for-convenience right with respect to the parties’ Manufacturing and Supply Agreement, dated as of May 14, 2014 and as amended from time to time (the “RLS Agreement”), which would have caused the RLS Agreement to terminate in December 2017. In addition, in March 2015, RLS initiated an arbitration proceeding under the RLS Agreement alleging that the RLS Agreement grants RLS exclusive global supply rights for BOW015, that the terms of the Company’s collaboration agreements with Fujifilm Diosynth Biotechnologies U.S.A., Inc. and Livzon MabPharm Inc. violate the RLS Agreement, and sought to terminate the RLS Agreement. The proceeding initiated by RLS sought a declaratory judgment, but did not seek any monetary damages. On April 22, 2015, the Company entered into a Settlement Agreement with RLS (the “Settlement Agreement”). Pursuant to the Settlement Agreement, the parties finalized the remaining BOW015 batch production schedule with RLS agreeing to manufacture 15 final batches of BOW015 on or before June 30, 2016 with the Company’s option to have RLS manufacture an additional 5 batches on or before December 31, 2016. In January 2016, the Company amended the Settlement with RLS to extend the time for RLS to manufacture the 15 final batches from June 30, 2016 to June 30, 2017. RLS has also agreed to use reasonable commercial efforts to transfer the existing Indian marketing authorization for BOW015 granted by the Drug Controller General of India (“DCGI”) to the Company or its designee, with all costs of the transfer to be borne by the Company and subject to the DCGI’s approval of such transfer. The Company has agreed to pay to RLS a fee of approximately $2,250 , payable in four installments over the course of the final batch manufacture, with the final installment to be paid no later than ten days after June 30, 2016. Pursuant to the Settlement Agreement, on May 4, 2015, RLS withdrew the arbitration proceeding it initiated, and the parties have agreed to release each other from all causes of actions or claims, present and future, arising under the RLS Agreement. Following the satisfaction by both parties of all of the terms of the Settlement Agreement, the RLS Agreement and related agreements between the parties shall be terminated and neither party shall have any further rights or obligations thereunder . The Company made the first payment of $750 on April 27, 2015 and made two additional payments of $500 on September 10, 2015 and February 3, 2016.

Subsequent Events

Subsequent Events	3 Months Ended
	Mar. 31, 2016
Subsequent Events
Subsequent Events	16. Subsequent Events On May 9, 2016, the Company announced the reprioritization of the Company’s pipeline to focus exclusively on developing biosimilars for the treatment of rare diseases. This will involve, among other things, reallocating the Company’s resources to focus on the development of BOW080 (eculizumab; reference biologic Soliris®) for the potential treatment of ultra-rare blood disorders and BOW070 (tocilizumab; reference biologic Actemra®) for the potential treatment of an uncommon lymphoproliferative disorder known as Castleman’s disease. The Company has also suspended development of what had previously been its lead program, BOW015 (infliximab, reference biologic Remicade®). The Company is engaged in a strategic review of its options, including with respect to the BOW015 program, which may include partnerships, divestitures and/or other value-generating alternatives. The Company’s decision to suspend its BOW015 program is based on cost-savings, not technical reasons, and the program remains ready to commence its planned global Phase 3 clinical study. If the Company is not able to form a partnership for or divestiture as planned for BOW015, the intangible asset associated with the BOW015 program w ith a carrying value of $3,323 as of March 31, 2016, may be subject to future impairment. The Company’s new focus on biosimilars that treat rare diseases necessitates a restructuring of the Company’s operations and a corresponding reduction in up to approximately 40% of its workforce, to align its resources more closely with its corporate objectives. Additionally, as announced on May 9, 2016, Amit Munshi, the Company’s President and Chief Executive Officer and a Director, has resigned from those positions with the Company. Scott Rocklage, a Director of the Company, has been appointed Acting Chief Executive Officer of the Company and Michael Wyand, the Company’s Chief Technical Officer, was appointed as President and Chief Operating Officer of the Company. In connection with these actions, the size of the Company’s Board has also been reduced from eight members to seven , with two members remaining in Class III.

Summary of Significant Accoun21

Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2016
Summary of Significant Accounting Policies
Principles of Consolidation	Principles of Consolidation The consolidated financial statements include the accounts of Epirus and its wholly owned subsidiaries as of March 31, 2016: EB Sub, Inc., a Delaware Corporation, Epirus Biopharmaceuticals Ltd., a United Kingdom corporation, Epirus Biopharmaceuticals (Switzerland) GmbH, a Swiss corporation, Epirus Brasil Tecnologia Ltda, a Brazilian corporation and Epirus Biopharmaceuticals (Netherlands) B.V., a Netherlands corporation. All significant intercompany balances and transactions have been eliminated in consolidation.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In November 2015, the FASB issued ASU 2015-17, “ Balance Sheet Classification of Deferred Taxes ”, which simplifies the presentation of deferred income taxes. This ASU requires that deferred tax assets and liabilities be classified as non-current in a statement of financial position. The standard is effective for public companies for fiscal years beginning after December 15, 2016, including interim periods within that reporting period. Early adoption is permitted for any interim and annual financial statements that have not yet been issued. The Company early adopted ASU 2015-17 effective December 31, 2015 on a prospective basis. Adoption of this ASU resulted in a reclassification of the net current deferred tax asset of $109 and the net current deferred tax liability of $80 to the net non-current deferred tax liability in the Company’s consolidated balance sheet as of December 31, 2015. In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842) . The new standard requires that all lessees recognize the assets and liabilities that arise from leases on the balance sheet and disclose qualitative and quantitative information about its leasing arrangements. The new standard will be effective for the Company on January 1, 2019. The Company is currently evaluating the potential impact that this standard may have on its consolidated financial statements. In March 2016, the FASB issued ASU No. 2016-06, Derivatives and Hedging (Topic 815): Contingent Put and Call Options in Debt Instruments . The new standard simplifies the embedded derivative analysis for debt instruments containing contingent call or put options by removing the requirement to assess whether a contingent event is related to interest rates or credit risks. The new standard will be effective for the Company on January 1, 2017. The adoption of this standard is not expected to have an impact on the Company’s consolidated financial statements. In March 2016, the FASB issued ASU No. 2016-09, Compensation – Stock Compensation , which amends ASC Topic 718, Compensation – Stock Compensation. The new standard identifies areas for simplification involving several aspects of accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities, an option to recognize gross stock compensation expense with actual forfeitures recognized as they occur, as well as certain classifications on the statement of cash flows. The amendments are effective for annual periods beginning after December 15, 2016, and interim periods within those annual periods. Early adoption is permitted. An entity that elects early adoption must adopt all of the amendments in the same period. The Company is currently evaluating the potential impact that ASU 2016-09 may have on the Company’s financial position or results of operations.

Acquisition (Tables)

Acquisition (Tables)	3 Months Ended
	Mar. 31, 2016
Acquisition
Schedule of acquisition-date fair value of consideration transferred	Initial equity consideration paid at closing Initial shares issued to Bioceros shareholders Price per Epirus share at issuance $ $ Initial cash consideration paid at closing Total consideration paid at closing Settlement of preexisting Epirus accounts payable to Bioceros (1) Second Installment Shares, excluding key employee stock compensation expense (2) Net cash payout (3) Final payment of cash consideration (4) Preliminary estimated purchase price $ (1) Represents the settlement of preexisting accounts payable to Bioceros as a result of activity prior to the transaction . (2) Represents the fair value of the undiscounted $3,985 of Second Installment Shares to be paid and issued on March 9, 2016, which excludes the undiscounted $1,015 of shares to be issued to Bioceros key employees contingent upon the delivery of postcombination service to the Company, as described above. This amount has been recorded as a liability on the Company’s consolidated balance sheet, because it represents an obligation to issue a variable number of shares based on a fixed dollar amount of $3,985 , and recorded at fair value utilizing a discount rate of 10.7% . (3) Represents the fair value of the net cash payout to be made pursuant to the Stock Purchase Agreement. This amount has been recorded as a contingent consideration liability on the Company’s consolidated balance sheet as of September 9, 2015 and recorded at fair value utilizing a discount rate of 10.7% . The amount of the net cash payout is dependent on revenue agreements signed from select Bioceros customers subsequent to the acquisition date and through December 31, 2015 . (4) Represents the fair value of the final cash payment of $1,700 , which, pursuant to the Stock Purchase Agreement, the Company will pay on September 9, 2016. This amount has been recorded as a liability on the Company’s consolidated balance sheet as of September 9, 201 5 and recorded at fair value utilizing a discount rate of 10.7% .
Summary of estimated fair values of the assets acquired and liabilities assumed at the date of acquisition	The following table summarizes the preliminary estimated fair values of the assets acquired and liabilities assumed at the date of acquisition: (in thousands) Cash and cash equivalents $ Deferred tax assets Accounts receivable Prepaid expenses and other current assets Property and equipment, net Intangible assets, net Goodwill Accounts payable Accrued expenses and other current liabilities Deferred revenue Deferred tax liabilities Net assets acquired $

Goodwill and Intangible Asset23

Goodwill and Intangible Assets, Net (Tables)	3 Months Ended
	Mar. 31, 2016
Goodwill and Intangible Assets, Net
Schedule of intangible assets, net of accumulated amortization	March 31, 2016 December 31, 2015 Intangible assets (excluding IPR&D) $ $ Less: accumulated amortization—intangible assets Intangible assets, net (excluding IPR&D) $ $
Schedule of estimated aggregate amortization of intangible assets	March 31, 2016 April 1, 2016 - December 31, 2016 $ 2017 2018 2019 2020 2021 and thereafter Total $

Accrued Expenses (Tables)

Accrued Expenses (Tables)	3 Months Ended
	Mar. 31, 2016
Accrued Expenses
Components of Accrued Expenses	March 31, 2016 December 31, 2015 Accrued compensation $ $ Accrued professional fees Accrued interest expense Other Total accrued expenses $ $

Debt (Tables)

Debt (Tables)	3 Months Ended
	Mar. 31, 2016
Debt
Schedule of future principal payments	Principal Payments April 1, 2016 - December 31, 2016 $ 2017 2018 Total $

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2016
Fair Value Measurements
Schedule of financial assets and liabilities measured at fair value on a recurring basis	As of March 31, 2016 Level 1 Level 2 Level 3 Total Assets Cash and cash equivalents $ $ — $ — $ $ $ — $ — $ As of December 31, 2015 Level 1 Level 2 Level 3 Total Assets Cash and cash equivalents $ $ — $ — $ $ $ — $ — $

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2016
Stock-Based Compensation
Summary of stock option activity	Weighted- Average Weighted- Remaining Average Contractual Aggregate Number Exercise Term Intrinsic of Options Price (in years) Value Outstanding at December 31, 2015 $ Granted Exercised — — Cancelled Outstanding at March 31, 2016 $ $ Vested and expected to vest at March 31, 2016 $ $ Exercisable at March 31, 2016 $ $ Weighted average grant-date fair value of options granted during the period $ Cash received upon exercise of options $ —
Summary of range of assumptions used in the Black-Scholes pricing model for grants and grants issued or accelerated in connections with the Merger	Three Months Ended March 31, 2016 2015 Risk-free interest rate 1.35% -1.82% Expected volatility 61.40% -62.53% Expected term (in years) Expected dividend yield
Summary of the activity of nonvested RSUs	Weighted- Average Number Weighted- Remaining of Average Contractual Aggregate Restricted Grant Date Term Intrinsic Stock Units Fair Value (in years) Value Nonvested at December 31, 2015 $ $ Granted — — — — Vested — — Cancelled — — Nonvested at March 31, 2016 $ $ Vested and expected to vest at: March 31, 2016 $ $ Exercisable at: March 31, 2016 — $ — — $ —

Commitments (Tables)

Commitments (Tables)	3 Months Ended
	Mar. 31, 2016
Commitments
Schedule of future minimum lease payments under operating leases	March 31, 2016 April 1, 2016 - December 31, 2016 $ 2017 2018 2019 2020 2021 and thereafter Total $ Less: Future sublease payments to be received Net future lease payments $

Net Loss Per Share (Tables)

Net Loss Per Share (Tables)	3 Months Ended
	Mar. 31, 2016
Net Loss Per Share
Summary of potentially dilutive securities outstanding excluded from the computation of diluted weighted-average shares outstanding	Three Months Ended March 31, 2016 2015 Options to purchase common stock Settlement of loan agreement Warrants to purchase common stock Nonvested restricted stock units Employee stock purchase plan — Nonvested restricted stock awards —

Organization (Details)

Organization (Details) - USD ($) $ in Thousands	May. 09, 2016	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Acquisition
Cash and cash equivalents		$ 20,865	$ 61,546	$ 20,865	$ 31,515	$ 21,462
Accumulated deficit		(155,025)		(155,025)	$ (138,759)
Net loss		$ (16,266)	$ (7,521)	$ 155,025
Forecast | Subsequent event
Acquisition
Percentage of expected workforce reduction	40.00%

Summary Of Significant Accoun31

Summary Of Significant Accounting Policies (Details) $ in Thousands	Dec. 31, 2015USD ($)
Summary of Significant Accounting Policies
Reclassification of net current deferred tax asset to net noncurrent deferred tax liability	$ 109
Reclassification of net current deferred tax liability to net noncurrent deferred tax liability	$ 80

Business Agreements (Details)

Business Agreements (Details) $ in Thousands	Sep. 24, 2015USD ($)item	Jul. 13, 2015product	May. 07, 2015installment	Jan. 03, 2014USD ($)	Jan. 31, 2016USD ($)	Mar. 31, 2016USD ($)	Mar. 31, 2015USD ($)	May. 13, 2015USD ($)
Business Agreements
Royalty revenue						$ 803	$ 25
Collaboration Agreement
Business Agreements
Percentage of costs under global development program		49.00%
Percentage of total clinical trial costs incurred under clinical trial programs		81.00%
Percentage of profit and loss sharing under development programs		49.00%
Sun Pharmaceutical Industries Limited | BOW015 | Royalty Bearing And Non Transferable License Agreement
Business Agreements
Outstanding royalty payments						40
Upfront payment received				$ 500
Maximum payments to be received for achievement of certain development and regulatory approval milestones						1,000
Maximum payments to be received for achievement of certain sales milestones						10,000
Amount payable for breach of license agreement						500
Sun Pharmaceutical Industries Limited | Infimab | Royalty Bearing And Non Transferable License Agreement
Business Agreements
Royalty revenue						40	$ 17
Invoiced amount						1,375
Proceeds received as per agreement						1,250
Mabxience S.A | BOW015 | Exclusive License and Collaboration Agreement
Business Agreements
Amount that could be earned for each first commercial sale in each territory country						$ 250
Collaborative Arrangements Term Of Agreement						15 years
Mabxience S.A | BOW015 | Maximum | Exclusive License and Collaboration Agreement
Business Agreements
Maximum payments to be received for achievement of certain sales milestones								$ 1,500
Polpharma
Business Agreements
Royalty revenue						$ 570
Royalties Received					$ 2,309
Deferred Revenue						$ 2,263
Polpharma | Collaboration Agreement
Business Agreements
Number of product programs | installment			3
Percentage of costs under global development program		51.00%
Cost sharing ratio percentage for clinical trial costs incurred in connection with global development		38.00%
Percentage of total clinical trial costs incurred under clinical trial programs		19.00%
Percentage of profit and loss sharing under development programs		51.00%
Polpharma | North America | Collaboration Agreement
Business Agreements
Number of products exclusive rights retained | product		3
Livzon Mabpharm Inc
Business Agreements
Ownership percentage						6.00%
Livzon Mabpharm Inc | BOW070 | Supplement Agreement
Business Agreements
Total payments to be made for the completion of the pre-clinical development activities	$ 4,500
Initial payment to be made for pre-clinical development activities upon entry into Supplement Agreement	$ 1,500
Initial payment term for pre-clinical development activities upon entry into Supplement Agreement	10 days
Number of additional payments to be made for the achievement of certain pre-clinical development milestones | item	3
Payments to be made for the achievement of certain pre-clinical development milestones	$ 1,000
Estimated period for expensing costs	18 months
Expense recorded	$ 500

Acquisition (Details)

Acquisition (Details) - USD ($)	Mar. 09, 2016	Mar. 08, 2016	Sep. 09, 2015	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Acquisition
Common stock, par value				$ 0.001		$ 0.001
Stock-based compensation expense				$ 1,999,000	$ 526,000
Estimated fair values of the assets acquired and liabilities assumed at the date of acquisition:
Goodwill				$ 26,361,000		$ 26,361,000
Period for final determination of allocation of consideration transferred, from acquisition date				1 year
Cash payout of liability						$ 409,000
Bioceros
Acquisition
Percentage of voting rights acquired			100.00%
Total consideration			$ 14,100,000
Cash payment liability			$ 1,700,000
Number of installments in which shares will be released				$ 3
Acquisition-date fair value of the consideration transferred
Stock issued in connection with purchase of Bioceros ( in shares)	1,772,107		788,960
Period used for calculating pre-closing date average share price	10 days
Average share Price	$ 2.82
Price per Epirus share at issuance			$ 5.79
Initial equity consideration paid at closing			$ 4,568,000
Initial cash consideration paid at closing			3,400,000
Total consideration paid at closing			7,968,000
Settlement of preexisting Epirus accounts payable to Bioceros			(87,000)
Second Installment Shares, excluding key employee stock compensation expense			3,788,000
Net cash payout			409,000
Final payment of cash consideration			1,535,000
Preliminary estimated purchase price			13,613,000
Estimated fair values of the assets acquired and liabilities assumed at the date of acquisition:
Cash and cash equivalents			889,000
Deferred tax assets			161,000
Accounts receivable			49,000
Prepaid expenses and other current assets			226,000
Property and equipment, net			447,000
Intangible assets, net			3,191,000
Goodwill			10,734,000
Accounts payable			(146,000)
Accrued expenses and other liabilities			(704,000)
Deferred revenue			(436,000)
Deferred tax liabilities			(798,000)
Total net assets acquired			13,613,000
Bioceros | Estimate of Fair Value Measurement
Acquisition
Cash payment liability			1,700,000
Fair value of issuance of shares related to acquisition			$ 3,985,000
Acquisition-date fair value of the consideration transferred
Discount rate (as a percent)			10.70%			10.70%
Bioceros | Final Cash Payment
Acquisition
Cash payment liability						$ 0
Acquisition-date fair value of the consideration transferred
Net cash payout			$ 409,000
Bioceros | Initial Issuance
Acquisition
Common stock, par value			$ 0.001
Value of common stock issuable			$ 4,000,000
Period of pre-closing date average price			10 years
Pre-closing date average price			$ 5.07
Fair value of issuance of shares related to acquisition			$ 4,568,000
Bioceros | Second Installment Shares
Acquisition
Fair value of issuance of shares related to acquisition			5,000,000
Bioceros | First Installment
Acquisition
Period after closing date after which shares will be released to key employees				12 months
Bioceros | Second Installment
Acquisition
Period after closing date after which shares will be released to key employees				18 months
Bioceros | Third Installment
Acquisition
Period after closing date after which shares will be released to key employees				24 months
Bioceros | Minimum
Acquisition
Threshold for payment of cash received from customers			$ 1,200,000
Key Employees of Acquired Company | Bioceros
Acquisition
Percentage of shares that will vest on first vesting date			75.00%
Stock-based compensation expense				$ 889,000
Key Employees of Acquired Company | Bioceros | Second Installment Shares
Acquisition
Fair value of issuance of shares related to acquisition	$ 1,015,000		$ 1,015,000
Key Employees of Acquired Company | Bioceros | Minimum | Second Installment Shares
Acquisition
Stock purchase Agreement		10.00%
Key Employees of Acquired Company | Bioceros | Maximum | Second Installment Shares
Acquisition
Stock purchase Agreement		19.99%

Goodwill and Intangible Asset34

Goodwill and Intangible Assets, Net - Goodwill (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Goodwill and Intangible Assets, Net
Goodwill	$ 26,361	$ 26,361
Accumulated goodwill impairment losses	$ 0

Goodwill and Intangible Asset35

Goodwill and Intangible Assets, Net - In-Process Research and Development and Other Intangible Assets Excluding Goodwill (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Intangible Assets
Intangible asset, useful life	11 years 7 months 6 days
Intangible assets, net of accumulated amortization
Intangible assets (excluding IPR&D)	$ 6,878		$ 6,878
Less: accumulated amortization--intangible assets	(667)		(468)
Intangible assets, net	6,211		$ 6,410
In Process Research and Development
Intangible assets, net of accumulated amortization
Amortization expense	$ 199	$ 57

Goodwill and Intangible Asset36

Goodwill and Intangible Assets, Net - Extimated Aggregate Amortization of Intangible Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Estimated future amortization expense related to finite-lived purchased intangible assets
April 1, 2016 - December 31, 2016	$ 558
2,017	757
2,018	757
2,019	757
2,020	757
2021 and thereafter	2,625
Total	$ 6,211	$ 6,410

Accrued Expenses (Details)

Accrued Expenses (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Accrued Expenses
Accrued compensation	$ 819	$ 2,057
Accrued professional fees	1,112	1,502
Accrued interest expense	311	264
Other	462	180
Total accrued expenses	$ 2,704	$ 4,003

Debt - Hercules Notes (Details)

Debt - Hercules Notes (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Debt
Short-term Debt	$ 14,852		$ 14,833
Hercules Notes
Debt
Outstanding borrowings	15,000
Short-term Debt	14,852
Unamortized Debt Discount	148
Amortization of the debt discount included in interest expense	$ 19	$ 16

Debt - Future Principal Payment

Debt - Future Principal Payments (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2016USD ($)
Debt
Term charge	3.00%
Hercules Notes
Future principal payments
April 1, 2016 - December 31, 2016	$ 3,693
2,017	5,940
2,018	5,367
Total	$ 15,000

Capital Stock (Details)

Capital Stock (Details) shares in Millions	Feb. 29, 2016shares
Capital Stock
Payment of Commission	3.00%
Sales agreement | Maximum
Capital Stock
Sales of Common stock through Sales Agent (in shares)	30

Fair Value Measurements - (Deta

Fair Value Measurements - (Details) - Recurring - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Estimate of Fair Value Measurement
Assets
Cash and cash equivalents	$ 20,865	$ 31,515
Total assets	20,865	31,515
Level 1
Assets
Cash and cash equivalents	20,865	31,515
Total assets	$ 20,865	$ 31,515

Stock-Based Compensation - Stoc

Stock-Based Compensation - Stock Options (Details) - USD ($) $ / shares in Units, $ in Thousands	Mar. 29, 2015	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015	Jun. 04, 2015
Stock-Based Compensation
Stock-based compensation expense		$ 1,999	$ 526
Reduced share based compensation expense		100
Weighted average fair value
Cash received from exercise of stock options			$ 245
Bioceros | Acquiree's employees
Stock-Based Compensation
Stock-based compensation expense		$ 889
Stock Options
Number of Options
Outstanding at the beginning of the period		3,613,427
Granted		54,400
Cancelled		(103,380)
Outstanding at the end of the period		3,564,447		3,613,427
Vested and expected to vest at end of period		3,421,869
Exercisable at end of period		1,047,693
Weighted-Average Exercise Price
Outstanding at the beginning of the period		$ 8.81
Granted		3.34
Cancelled		6.49
Outstanding at the end of the period		8.80		$ 8.81
Vested and expected to vest at end of period		8.80
Exercisable at end of period		$ 12.81
Weighted-Average Remaining Contractual Term
Outstanding at end of period		8 years 8 months 12 days		8 years 9 months 18 days
Vested and expected to vest at end of period		8 years 8 months 12 days
Exercisable at end of period		7 years 9 months 18 days
Aggregate Intrinsic Value
Outstanding at end of period		$ 390		$ 485
Vested and expected to vest at end of period		374
Exercisable at end of period		$ 297
Weighted average fair value
Weighted average grant-date fair value of options granted during the period		$ 2.34
Unrecognized stock-based compensation expense
Unrecognized stock-based compensation expense		$ 10,025
Unrecognized stock-based compensation expense, Recognition period		2 years 10 months 24 days
Weighted-average assumptions
Risk-free interest rate		1.58%
Expected volatility		82.00%
Expected term		6 years	6 years
Expected dividend yield		0.00%	0.00%
Stock Options | Minimum
Weighted-average assumptions
Risk-free interest rate			1.35%
Expected volatility			61.40%
Stock Options | Maximum
Weighted-average assumptions
Risk-free interest rate		1.82%
Expected volatility			62.53%
2015 Plan
Stock-Based Compensation
Authorized number of shares					1,700,000
Increase in Authorized number of shares	975,102

Stock-Based Compensation - Rest

Stock-Based Compensation - Restricted Stock Units (Details) - USD ($) $ / shares in Units, $ in Thousands	Feb. 29, 2016	Mar. 29, 2015	Feb. 28, 2015	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Aggregate Intrinsic value
Exercisable, Aggregate Intrinsic Value
Stock-based compensation expense				$ 1,999	$ 526
Nonvested restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares
Non-vested at beginning of period				124,442
Granted			117,131
Vested				(38,238)
Cancelled				(852)
Non-vested at end of period				85,352		124,442
Vested and expected to vest at the end of period ( in units)				81,938
Exercisable, Number of Restricted Stock Units
Weighted-Average Exercise Price
Nonvested at the beginning of the period				$ 10.53
Vested, Weighted-Average Grant Date Fair Value				10.53
Cancelled				10.53
Nonvested at the end of the period				10.53		$ 10.53
Vested and expected to vest at end of period				$ 10.53
Exercisable at end of period
Weighted Average Remaining Contractual Term
Non-vested Weighted Average Remaining Contractual Term (in years)				1 year 10 months 24 days		2 years 10 months 24 days
Vested and expected to vest at the end of period ( in years)				1 year 10 months 24 days
Aggregate Intrinsic value
Non-vested, Aggregate Intrinsic Value				$ 230		$ 385
Vested and expected to vest, Aggregate Intrinsic Value				221
Unrecognized stock-based compensation expense				$ 872
Unrecognized stock-based compensation expense, Recognition period				2 years 10 months 24 days
Percentage of shares that will vest on first vesting date				25.00%
Percentage of shares that will vest on subsequent vesting date				25.00%
RSU Issued As Merit Grants
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares
Granted			9,490
2015 Plan
Aggregate Intrinsic value
Increase in Common stock		975,102
Options to purchase common stock
Aggregate Intrinsic value
Shares available for issuance				472,722
Percentage of market price				85.00%
Increase in Common stock	120,000

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Income Taxes
Income tax expense (benefit)	$ (42)	$ (12)
Amortization of the tax benefit	46	46
Foreign withholding taxes	$ 4	27
Minimum state taxes due		$ 7

Commitments (Details)

Commitments (Details) $ in Thousands	Mar. 31, 2016USD ($)
Future minimum lease payments
April 1, 2016 - December 31, 2016	$ 1,791
2,017	1,106
2,018	644
2,019	655
2,020	666
2021 and Thereafter	464
Total	5,326
Less: Future sublease payments to be received	(941)
Net future lease payments	$ 4,385

Net Loss Per Share (Details)

Net Loss Per Share (Details) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Options to purchase common stock
Net Loss Per Share
Securities excluded from the computation of diluted weighted-average shares outstanding	3,564,447	2,411,898
Nonvested restricted stock units
Net Loss Per Share
Securities excluded from the computation of diluted weighted-average shares outstanding	248,093	248,093
Employee stock option plan
Net Loss Per Share
Securities excluded from the computation of diluted weighted-average shares outstanding	92,892	93,040
Settlement of short-term debt
Net Loss Per Share
Securities excluded from the computation of diluted weighted-average shares outstanding	85,352	126,621
Nonvested restricted stock awards
Net Loss Per Share
Securities excluded from the computation of diluted weighted-average shares outstanding	10,586
Warrants to purchase common stock
Net Loss Per Share
Securities excluded from the computation of diluted weighted-average shares outstanding		13,259

Legal Proceedings (Details)

Legal Proceedings (Details) - BOW015 - Reliance Life Sciences Ltd $ in Thousands	Sep. 10, 2015USD ($)	Apr. 27, 2015USD ($)	Apr. 22, 2015USD ($)installmentitem	Dec. 31, 2014
Legal Proceedings
Termination period				3 years
Settlement Agreement
Legal Proceedings
Number of final batches to be manufactured on or before June 30,2016 | item			15
Number of final batches to be manufactured on or before December 31, 2016 | item			5
Agreed to pay as a fee | $			$ 2,250
Number of installments for payable of amount agreed | installment			4
Maximum payment term for final installment			10 years
Payment amount | $	$ 500	$ 750

Subsequent Events (Details)

Subsequent Events (Details) $ in Thousands	May. 09, 2016director	May. 08, 2016director	Mar. 31, 2016USD ($)
Subsequent Events
Number of board members	7	8
Class III
Subsequent Events
Number of board members	2
Subsequent event | Forecast
Subsequent Events
Percentage of expected workforce reduction	40.00%
BOW015
Subsequent Events
Intangible asset | $			$ 3,323