XenoPort (XNPT) 10-Q 7 Aug 14 2014 Q2 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	6 Months Ended
	Jun. 30, 2014	Jul. 15, 2014
Document Type	'10-Q	'
Amendment Flag	'false	'
Document Period End Date	30-Jun-14	'
Document Fiscal Year Focus	'2014	'
Document Fiscal Period Focus	'Q2	'
Trading Symbol	'XNPT	'
Entity Registrant Name	'XENOPORT INC	'
Entity Central Index Key	'0001130591	'
Current Fiscal Year End Date	'--12-31	'
Entity Filer Category	'Accelerated Filer	'
Entity Common Stock, Shares Outstanding	'	62,211,589

BALANCE_SHEETS

BALANCE SHEETS (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Current assets:	'	'
Cash and cash equivalents	$32,652	$20,584
Short-term investments	92,294	38,074
Accounts receivable	1,648	939
Inventories, net	1,217	1,262
Prepaids and other current assets	3,573	2,826
Total current assets	131,384	63,685
Property and equipment, net	2,376	2,552
Long-term inventories	9,891	10,185
Restricted investments and other assets	1,975	2,119
Total assets	145,626	78,541
Current liabilities:	'	'
Accounts payable	3,537	1,432
Accrued compensation	3,664	2,741
Accrued preclinical and clinical costs	841	824
Other accrued liabilities	6,185	3,938
Deferred revenue	21,135	1,134
Total current liabilities	35,362	10,069
Deferred revenue	11,430	11,997
Other noncurrent liability	3,015	2,782
Commitments and contingencies	'	'
Stockholders' equity:	'	'
Preferred stock, $0.001 par value; 5,000 shares authorized; no shares issued or outstanding	0	0
Common stock, $0.001 par value; 100,000 shares authorized; 62,094 and 47,800 shares issued and outstanding at June 30, 2014 and December 31, 2013, respectively	62	48
Additional paid-in capital	673,161	591,128
Accumulated other comprehensive income	14	0
Accumulated deficit	-577,418	-537,483
Total stockholders' equity	95,819	53,693
Total liabilities and stockholders' equity	$145,626	$78,541

BALANCE_SHEETS_Parenthetical

BALANCE SHEETS (Parenthetical) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, except Per Share data, unless otherwise specified
Preferred stock, par value	$0.00	$0.00
Preferred stock, shares authorized	5,000	5,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$0.00	$0.00
Common stock, shares authorized	100,000	100,000
Common stock, shares issued	62,094	47,800
Common stock, shares outstanding	62,094	47,800

STATEMENTS_OF_COMPREHENSIVE_LO

STATEMENTS OF COMPREHENSIVE LOSS (USD $)	3 Months Ended		6 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Revenues:	'	'	'	'
Product sales, net	$4,920	$1,640	$7,877	$1,640
Collaboration revenue	283	379	566	758
Royalty revenue	131	67	266	147
Total revenues	5,334	2,086	8,709	2,545
Operating expenses:	'	'	'	'
Cost of product sales	599	249	1,029	249
Research and development	5,203	10,236	9,860	23,589
Selling, general and administrative	18,865	15,788	37,636	26,523
Total operating expenses	24,667	26,273	48,525	50,361
Loss from operations	-19,333	-24,187	-39,816	-47,816
Interest income	66	58	115	139
Interest expense	-120	-252	-234	-252
Net loss	-19,387	-24,381	-39,935	-47,929
Other comprehensive loss:	'	'	'	'
Unrealized gains (losses) on available-for-sale securities	18	-20	14	-39
Comprehensive loss	($19,369)	($24,401)	($39,921)	($47,968)
Basic and diluted net loss per share	($0.31)	($0.51)	($0.67)	($1.01)
Shares used to compute basic and diluted net loss per share	61,994	47,473	59,441	47,361

STATEMENTS_OF_CASH_FLOWS

STATEMENTS OF CASH FLOWS (USD $)	6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013
Operating activities	'	'
Net loss	($39,935)	($47,929)
Adjustments to reconcile net loss to net cash used in operating activities:	'	'
Depreciation	353	580
Accretion of investment discounts and amortization of investment premiums, net	491	563
Stock-based compensation expense	5,109	5,839
Changes in assets and liabilities:	'	'
Accounts receivable	-709	-1,466
Prepaid and other current and noncurrent assets	-603	-947
Inventories	339	-200
Accounts payable	2,105	2,842
Accrued compensation	924	-1,070
Accrued restructuring charges	'	-844
Accrued preclinical and clinical costs	17	-1,841
Other accrued liabilities, current and noncurrent	2,480	1,599
Deferred revenue	19,434	-758
Net cash used in operating activities	-9,995	-43,632
Investing activities	'	'
Purchases of investments	-103,541	-62,222
Proceeds from maturities of investments	48,843	83,749
Purchases of property and equipment	-177	-271
Net cash (used in) provided by investing activities	-54,875	21,256
Financing activities	'	'
Net cash proceeds provided by (used in) issuance of common stock and exercise of stock options	76,938	-1,135
Net cash provided by (used in) financing activities	76,938	-1,135
Net increase (decrease) in cash and cash equivalents	12,068	-23,511
Cash and cash equivalents at beginning of period	20,584	36,134
Cash and cash equivalents at end of period	$32,652	$12,623

Organization_and_Summary_of_Si

Organization and Summary of Significant Accounting Policies	6 Months Ended
	Jun. 30, 2014
Organization and Summary of Significant Accounting Policies	'
	1. Organization and Summary of Significant Accounting Policies
	Nature of Operations
	XenoPort, Inc., or the Company, was incorporated in the state of Delaware on May 19, 1999. The Company is a biopharmaceutical company focused on developing and commercializing a portfolio of internally discovered product candidates for the potential treatment of neurological and other disorders. The Company is currently commercializing HORIZANT® (gabapentin enacarbil) Extended-Release Tablets in the United States and developing its novel fumaric acid ester product candidate, XP23829, as a potential treatment for psoriasis and/or relapsing forms of multiple sclerosis, or MS. The Company’s other product candidates are: XP21279 and arbaclofen placarbil, or AP, which is licensed to Reckitt Benckiser Pharmaceuticals, Inc. Effective June 2014, the Company granted to Reckitt exclusive, world-wide rights to develop and commercialize pharmaceutical products containing AP and other prodrugs of baclofen or R-baclofen, or collectively, the AP Products, for all indications, subject to the Company’s right of first negotiation with Reckitt to collaborate to develop and commercialize AP Products for non-addiction indications (See Note 2 for more information). XP21279 is a potential treatment for patients with advanced idiopathic Parkinson’s disease. The Company may develop it further, to the extent that its resources permit, or it may enter into collaboration, partnership, licensing and other similar form of arrangements with third parties, collectively referred to as collaboration arrangements, for such development. HORIZANT and the Company’s product candidates are prodrugs that are typically created by modifying the chemical structure of currently marketed drugs, referred to as parent drugs, and are designed to correct limitations in the oral absorption, distribution and/or metabolism of the parent drug. HORIZANT and each of the Company’s product candidates are orally-available, patented molecules that address potential markets with clear unmet medical needs. The Company’s facilities are located in Santa Clara, California.
	On November 8, 2012, the Company reached an agreement with Glaxo Group Limited, or GSK, to terminate the Amended and Restated Development and Commercialization Agreement dated November 7, 2010, between the Company and GSK regarding HORIZANT and resolved all ongoing litigation between the parties. Under the terms of the November 2012 termination and transition agreement, during a transition period that ended on April 30, 2013, GSK continued to exclusively commercialize, promote, manufacture and distribute HORIZANT in the United States. The Company was not eligible to receive any milestone payments from GSK and did not receive any revenue or incur any losses from GSK’s sales of HORIZANT during the transition period. GSK continued to fully fund the costs associated with the management and conduct of required post-marketing clinical studies initiated by GSK prior to the date of the termination and transition agreement. In addition, GSK provided to the Company inventory of gabapentin enacarbil in GSK’s possession that was not required for use by GSK in the manufacture of HORIZANT and related manufacturing property and equipment. In exchange for such inventory, the Company will make annual payments to GSK of $1,000,000 for six years beginning in 2016, which was recorded at its present value as “Other noncurrent liability” on the Company’s balance sheet for the periods ended June 30, 2014 and December 31, 2013 and is being accreted to its contractual value over the payment period. On May 1, 2013, the Company completed the acquisition of the HORIZANT business in accordance with the termination and transition agreement and assumed all responsibilities and associated rights for the further development, manufacturing and commercialization of HORIZANT in the United States on that date. GSK was responsible for the commercial manufacture and supply of HORIZANT during the transition period. The Company did not assume any liabilities of GSK’s HORIZANT business as of the acquisition date.
	On January 29, 2014, the Company completed an underwritten public offering of 12,000,000 shares of its common stock at a price to the public of $6.00 per share. Net cash proceeds from the public offering were $67,300,000, after deducting the underwriting discounts and commissions and offering expenses payable by the Company. On February 21, 2014, the underwriters exercised in full their option to purchase 1,800,000 additional shares resulting in additional net cash proceeds of $10,100,000, after deducting the underwriting discounts and commissions and offering expenses payable by the Company.
	Basis of Preparation
	The accompanying financial statements as of June 30, 2014 and for the three and six months ended June 30, 2014 and 2013 are unaudited. These unaudited financial statements have been prepared on the same basis as the annual financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary to present fairly the Company’s financial position as of June 30, 2014 and comprehensive losses for the three and six months ended June 30, 2014 and 2013, and cash flows for the six months ended June 30, 2014 and 2013. The Financial Accounting Standards Board, or FASB, Accounting Standards Codification, or the Codification, is the single source of authoritative U.S. generally accepted accounting principles, or GAAP. The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results could differ from these estimates. The results of operations for the three and six months ended June 30, 2014 are not necessarily indicative of the results to be expected for the year ending December 31, 2014, or for any other interim period or any other future year. For more complete financial information, these financial statements, and the notes hereto, should be read in conjunction with the audited financial statements for the year ended December 31, 2013 included in the Company’s Annual Report on Form 10-K filed with the Securities and Exchange Commission on February 28, 2014. The results of operations of the acquired HORIZANT business, along with the fair values of the assets acquired in the transaction, have been included in the Company’s financial statements since the May 1, 2013 acquisition date.
	Recent Accounting Pronouncement
	In May 2014, the FASB issued Accounting Standards Update No. 2014-09, Revenue from Contracts with Customers: Topic 606 (ASU 2014-09), which creates a single source of revenue guidance under US GAAP for all companies in all industries. The core principle of ASU 2014-09 is that revenue should be recognized in a manner that depicts the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. ASU 2014-09 defines a five-step process in order to achieve this core principle, which may require the use of judgment and estimates. ASU 2014-09 also requires expanded qualitative and quantitative disclosures relating to the nature, amount, timing and uncertainty of revenue and cash flows arising from contracts with customers, including significant judgments and estimates used. ASU 2014-09 will be effective for the Company in the first quarter of fiscal 2017 and early adoption is not permitted. The Company may adopt ASU 2014-09 either by way of a full retrospective approach for all periods presented in the period of adoption or a modified retrospective approach. The Company is currently evaluating the impact that ASU 2014-09 will have on its financial statements and also has not yet determined which transition method it will apply.

Collaboration_Arrangements

Collaboration Arrangements	6 Months Ended
	Jun. 30, 2014
Collaboration Arrangements	'
	2. Collaboration Arrangements
	Reckitt Benckiser Pharmaceuticals, Inc.
	On May 14, 2014, the Company entered into an exclusive license agreement with Reckitt, which became effective on June 19, 2014. Under the terms of this agreement, the Company granted to Reckitt exclusive, world-wide rights to develop and commercialize AP Products for all indications, subject to its right of first negotiation with Reckitt to collaborate to develop and commercialize AP Products for non-addiction indications. In exchange for these rights, the Company received an upfront, non-refundable cash payment of $20,000,000 during the three months ended June 30, 2014 and also received an additional $5,000,000 in July 2014 after delivery of certain materials to Reckitt. The Company is also eligible to receive aggregate cash payments of up to $120,000,000 upon the achievement by Reckitt of certain contingent event-based milestones, of which $70,000,000 are regulatory and development-based and $50,000,000 are commercialization-based. In addition, the Company is entitled to receive tiered double-digit royalty payments of up to the mid-teens on a percentage basis on potential future net sales of the products in the United States, and high single-digit royalty payments on potential future net sales of the products outside the United States. The Company will also transfer its existing AP Investigational New Drug applications, or INDs, know-how and other related data, and provide technology transfer assistance to facilitate the establishment of Reckitt’s manufacturing and supply capabilities pursuant to a supply transition plan to be mutually agreed upon. The initial upfront cash payment of $20,000,000 received during the three months ended June 30, 2014 and the additional cash payment of $5,000,000 received in July 2014 will be recognized as collaboration revenue upon the transfer of all the related INDs, know-how and other related data, and completion of the supply transition plan, which the Company believes will occur during the second half of 2014.
	Astellas Pharma Inc.
	In December 2005, the Company entered into an agreement pursuant to which it licensed to Astellas Pharma Inc. exclusive rights to develop and commercialize gabapentin enacarbil in Japan, Korea, the Philippines, Indonesia, Thailand and Taiwan. Astellas began selling gabapentin enacarbil in Japan in July 2012 under the trade name of REGNITE® (gabapentin enacarbil) Extended-Release Tablets. In May 2013, the rights to gabapentin enacarbil in Korea, the Philippines, Indonesia, Thailand and Taiwan reverted to the Company after Astellas notified the Company that it did not have plans for the commercialization of gabapentin enacarbil in these five Asian countries in its territory. In the three and six months ended June 30, 2014, the Company recognized revenue of $283,000 and $566,000, respectively, representing amortization of the up-front license payment under this agreement. In the three and six months ended June 30, 2013, the Company recognized revenue of $379,000 and $758,000, respectively, representing amortization of the up-front license payment under this agreement. In the three and six months ended June 30, 2014, the Company recognized $131,000 and $266,000, respectively, in royalty revenue. In the three and six months ended June 30, 2013, the Company recognized $67,000 and $147,000, respectively, in royalty revenue. As of June 30, 2014, the Company had recognized an aggregate of $53,210,000 of revenue pursuant to this agreement. At June 30, 2014, $12,565,000 of revenue was deferred under this agreement and is being recognized on a straight-line basis over a period that the Company expects to remain obligated to provide services, of which $1,135,000 was classified within current liabilities and the remaining $11,430,000 was recorded as a noncurrent liability.

Acquisition_of_HORIZANT

Acquisition of HORIZANT	6 Months Ended
	Jun. 30, 2014
Acquisition of HORIZANT	'
	3. Acquisition of HORIZANT
	On May 1, 2013, the Company obtained control of, and thus completed the acquisition of, certain assets of HORIZANT that constituted an acquisition of a business as defined under the provisions of the Business Combinations topic of the Codification. Accordingly, the transaction reflected the recording of the acquisition date fair values of the acquired inventory and manufacturing property and equipment assets. Assets acquired as a result of this transaction were as follows (in thousands):
	Inventories	$	11,733
	Manufacturing property and equipment		1,967
	Total assets acquired	$	13,700
	Inventories were comprised of acquired raw materials, specifically gabapentin enacarbil, and were valued using the cost approach. The cost approach provides a framework for estimating value based on the principle of substitution. The estimated fair value was calculated based on the costs to replace or reproduce the asset, including the cost of recrystallization of the raw material received, while considering any impact on the value of any obsolescence.
	Manufacturing property and equipment acquired included certain equipment and a dedicated manufacturing suite for use in the manufacture of HORIZANT and was recorded at fair value using the replacement cost method. The replacement cost method uses an estimate of the cost of replacing or reproducing an asset to measure value. This amount is then reduced to reflect the amount of depreciation that has accrued given the asset’s age. Other factors and adjustments are considered in concluding on the fair value, including obsolescence of the acquired assets. Depreciation and amortization is computed using the straight-line method over the estimated useful lives of the respective assets, which is ten years.

Net_Loss_per_Share

Net Loss per Share	6 Months Ended
	Jun. 30, 2014
Net Loss per Share	'
	4. Net Loss per Share
	Basic net loss per share is calculated by dividing the net loss by the weighted-average number of common shares outstanding for the period without consideration for potential common shares. Diluted net loss per share is computed by dividing the net loss by the weighted-average number of common shares outstanding for the period plus any dilutive potential common shares for the period determined using the treasury-stock method. For purposes of this calculation, restricted stock units, options to purchase stock and warrants are considered to be potential common shares and are only included in the calculation of diluted net loss per share when their effect is dilutive.
		Three Months						Six Months
		Ended June 30,						Ended June 30,
		2014			2013			2014			2013
		(In thousands, except per share amounts)
	Numerator:
	Net loss	$	(19,387	)	$	(24,381	)	$	(39,935	)	$	(47,929	)
	Denominator:
	Weighted-average common shares outstanding		61,994			47,473			59,441			47,361
	Basic and diluted net loss per share	$	(0.31	)	$	(0.51	)	$	(0.67	)	$	(1.01	)
	Outstanding securities at period end not included in the computation of diluted net loss per share as they had an anti-dilutive effect:
	Restricted stock units and options to purchase common stock		8,148			7,179			8,148			7,179
	Warrants outstanding		—			283			—			283
			8,148			7,462			8,148			7,462

Cash_and_Cash_Equivalents_Shor

Cash and Cash Equivalents, Short-Term Investments and Restricted Investments	6 Months Ended
	Jun. 30, 2014
Cash and Cash Equivalents, Short-Term Investments and Restricted Investments	'
	5. Cash and Cash Equivalents, Short-Term Investments and Restricted Investments
	The carrying amounts of certain of the Company’s financial instruments, including cash, cash equivalents, short-term investments and restricted investments, are stated at fair value. The Company accounts for the fair value of its financial instruments in accordance with the provisions of the Fair Value Measurement topic of the Codification.
	Fair value is the price that would be received to sell an asset or paid to transfer a liability (an exit price) in an orderly transaction between market participants at the measurement date. The Company applies the market approach valuation technique for fair value measurements on a recurring basis and attempts to maximize the use of observable inputs and minimize the use of unobservable inputs. The fair value hierarchy prioritizes the inputs to valuation techniques used to measure fair value into three broad levels. All of the Company’s cash equivalents and short-term investments are measured using inputs classified at Level 1 or Level 2 within the fair value hierarchy. Level 1 inputs are quoted prices in active markets for identical assets. Level 2 inputs are based upon quoted prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active and model-based valuation techniques for which all significant inputs are observable in the market or can be corroborated by observable market data for substantially the full term of the assets. Level 3 inputs are unobservable inputs that are supported by little or no market activity and are significant to the fair value of the assets or liabilities. Where applicable, these models project future cash flows and discount the future amounts to a present value using market-based observable inputs obtained from various third-party data providers, including but not limited to, benchmark yields, interest rate curves, reported trades, broker/dealer quotes and market reference data.
	The following are summaries of cash and cash equivalents, short-term investments and restricted investments (in thousands):
		Cost		Gross		Gross			Estimated
				Unrealized		Unrealized			Fair
				Gains		Losses			Value
	As of June 30, 2014:
	Cash	$	20,777	$	—	$	—		$	20,777
	Money market funds		11,875		—		—			11,875
	Corporate debt securities		92,280		21		(7	)		92,294
	Certificates of deposit		1,725		—		—			1,725
		$	126,657	$	21	$	(7	)	$	126,671
	Reported as:
	Cash and cash equivalents								$	32,652
	Short-term investments									92,294
	Restricted investments									1,725
									$	126,671
		Cost		Gross		Gross			Estimated
				Unrealized		Unrealized			Fair
				Gains		Losses			Value
	As of December 31, 2013:
	Cash	$	2,281	$	—	$	—		$	2,281
	Money market funds		10,046		—		—			10,046
	U.S. government-sponsored agencies		2,500		—		—			2,500
	Corporate debt securities		43,831		6		(6	)		43,831
	Certificates of deposit		1,725		—		—			1,725
		$	60,383	$	6	$	(6	)	$	60,383
	Reported as:
	Cash and cash equivalents								$	20,584
	Short-term investments									38,074
	Restricted investments									1,725
									$	60,383
	At June 30, 2014, the contractual maturities of all investments held were less than 17 months. At December 31, 2013, the contractual maturities of all investments held were less than one year. All investments have been designated as available-for-sale, and changes to unrealized gains and losses are reflected as the only components of accumulated other comprehensive loss. The Company views its available-for-sale portfolio as available for use in current operations. Accordingly, the Company has classified all investments as short-term, even though the stated maturity may be one year or more beyond the current balance sheet date.
	No gross realized gains or losses were recognized and accordingly, there were no amounts reclassified out of accumulated other comprehensive loss to earnings in the three and six months ended June 30, 2014 or in the same periods in 2013.
	The Company’s available-for-sale investments, which include cash equivalents and short-term investments, are measured at fair value on a recurring basis and were classified at the following fair value hierarchy (in thousands):
	Description	Total As of		Fair Value Measurements at Reporting Date Using
		June 30,
		2014		Quoted Prices		Significant			Significant
				in Active		Other			Unobservable
				Markets		Observable			Inputs
				for Identical		Inputs			(Level 3)
				Assets		(Level 2)
				(Level 1)
	Money market funds	$	11,875	$	11,875	$	—		$	—
	Corporate debt securities		92,294		—		92,294			—
	Certificates of deposit		1,725		—		1,725			—
	Total	$	105,894	$	11,875	$	94,019		$	—
	Description	Total As of		Fair Value Measurements at Reporting Date Using
		December 31,
		2013		Quoted Prices		Significant			Significant
				in Active		Other			Unobservable
				Markets		Observable			Inputs
				for Identical		Inputs			(Level 3)
				Assets		(Level 2)
				(Level 1)
	Money market funds	$	10,046	$	10,046	$	—		$	—
	U.S. government-sponsored agencies		2,500		—		2,500			—
	Corporate debt securities		43,831		—		43,831			—
	Certificates of deposit		1,725		—		1,725			—
	Total	$	58,102	$	10,046	$	48,056		$	—

Inventories

Inventories	6 Months Ended
	Jun. 30, 2014
Inventories	'
	6. Inventories
	Inventories are stated at the lower of cost or market. Cost is determined on a first-in, first-out, or FIFO, basis. The Company regularly evaluates the Company’s inventories for excess quantities and obsolescence, including potential expirations, taking into account such factors as historical and anticipated future sales compared to quantities on hand and the remaining shelf life of HORIZANT. Write-downs of inventories are considered to be permanent reductions in the cost basis of inventories.
	Inventories that are not expected to be consumed within 12 months following the balance sheet date are classified as long-term inventories.
	Inventories as of June 30, 2014 and December 31, 2013 were as follows (in thousands):
		June 30,		December 31,
		2014		2013
	Raw materials	$	9,647	$	10,258
	Work in progress		363		76
	Finished goods		1,098		1,113
	Total inventory		11,108		11,447
	Less: Long-term inventories		9,891		10,185
	Total inventory classified as current	$	1,217	$	1,262
	Long-term inventories consist of active pharmaceutical ingredient, or API, of gabapentin enacarbil, as well as work in progress inventory as of June 30, 2014, used for production of HORIZANT. The Company evaluates demand for HORIZANT and expected consumption of the API based on long-term projected sales of HORIZANT.

Other_Accrued_Liabilities

Other Accrued Liabilities	6 Months Ended
	Jun. 30, 2014
Other Accrued Liabilities	'
	7. Other Accrued Liabilities
	Other accrued liabilities at June 30, 2014 and December 31, 2013 were as follows (in thousands):
		June 30,		December 31,
		2014		2013
	Accrued product costs	$	1,938	$	1,903
	Accrued selling and marketing expenses		2,068		883
	Accrued general and administrative expenses		1,365		632
	Accrued rebates, allowances and returns		504		315
	Other liabilities		310		205
	Total other accrued liabilities	$	6,185	$	3,938

StockBased_Compensation

Stock-Based Compensation	6 Months Ended
	Jun. 30, 2014
Stock-Based Compensation	'
	8. Stock-Based Compensation
	Details of the Company’s employee non-cash stock-based compensation were as follows (in thousands):
		Three Months				Six Months
		Ended June 30,				Ended June 30,
		2014		2013		2014		2013
	Research and development	$	622	$	710	$	1,324	$	1,905
	Selling, general and administrative		1,803		1,785		3,785		3,934
		$	2,425	$	2,495	$	5,109	$	5,839

Commitments_and_Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2014
Commitments and Contingencies	'
	9. Commitments and Contingencies
	On February 10, 2014, Clinton Relational Opportunity Master Fund, L.P., or the Clinton Group, initiated a proxy contest by notifying the Company of its intent to present proposals and to nominate three persons for election to the Company’s board of directors, or the Board, in opposition to the Board’s nominees, at the Company’s 2014 Annual Meeting of Stockholders, or the Annual Meeting. The uncertainties associated with the Clinton Group’s proxy contest have been resolved, and none of their Board nominations were elected by the Company’s stockholders at the Annual Meeting. Accordingly, the Company does not expect to incur any significant costs related to this matter in the future.

Stockholders_Equity

Stockholders' Equity	6 Months Ended
	Jun. 30, 2014
Stockholders' Equity	'
	10. Stockholders’ Equity
	Equity Incentive Plans
	2014 Equity Incentive Plan
	On June 11, 2014, the Company’s stockholders approved the 2014 Equity Incentive Plan, or the 2014 Plan. The 2014 Plan is intended to be the successor to XenoPort’s 2005 Equity Incentive Plan, 2005 Non-Employee Directors’ Stock Option Plan and 2010 Inducement Award Plan, collectively referred to as the Prior Plans. The terms of the 2014 Plan provide for the grant of incentive stock options, nonstatutory stock options, stock appreciation rights, restricted stock awards, restricted stock unit awards, other stock awards and performance awards that may be settled in cash, stock or other property. The total number of shares of the Company’s common stock available for issuance under the 2014 Plan is initially 4,471,059 shares plus up to an additional 7,847,852 Returning Shares (as defined below) as such shares become available from time to time. “Returning Shares” means the shares subject to outstanding awards granted under the Prior Plans and the 1999 Stock Plan that, from and after the effective date of the 2014 Plan: (a) expire or terminate for any reason prior to exercise or settlement; (b) are forfeited, cancelled or otherwise returned to the Company because of the failure to meet a contingency or condition required for the vesting of such shares; or (c) other than with respect to outstanding stock options and stock appreciation rights granted under the Prior Plans or the 1999 Stock Plan with an exercise or strike price of at least 100% of the fair market value of the underlying Company common stock on the date of grant, are reacquired or withheld (or not issued) by the Company to satisfy a tax withholding obligation in connection with a stock award. Eligible participants under the 2014 Plan include the Company’s employees and directors, including the Company’s executive officers and consultants.

Organization_and_Summary_of_Si1

Organization and Summary of Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2014
Basis of Preparation	'
	Basis of Preparation
	The accompanying financial statements as of June 30, 2014 and for the three and six months ended June 30, 2014 and 2013 are unaudited. These unaudited financial statements have been prepared on the same basis as the annual financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary to present fairly the Company’s financial position as of June 30, 2014 and comprehensive losses for the three and six months ended June 30, 2014 and 2013, and cash flows for the six months ended June 30, 2014 and 2013. The Financial Accounting Standards Board, or FASB, Accounting Standards Codification, or the Codification, is the single source of authoritative U.S. generally accepted accounting principles, or GAAP. The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results could differ from these estimates. The results of operations for the three and six months ended June 30, 2014 are not necessarily indicative of the results to be expected for the year ending December 31, 2014, or for any other interim period or any other future year. For more complete financial information, these financial statements, and the notes hereto, should be read in conjunction with the audited financial statements for the year ended December 31, 2013 included in the Company’s Annual Report on Form 10-K filed with the Securities and Exchange Commission on February 28, 2014. The results of operations of the acquired HORIZANT business, along with the fair values of the assets acquired in the transaction, have been included in the Company’s financial statements since the May 1, 2013 acquisition date.
Recent Accounting Pronouncement	'
	Recent Accounting Pronouncement
	In May 2014, the FASB issued Accounting Standards Update No. 2014-09, Revenue from Contracts with Customers: Topic 606 (ASU 2014-09), which creates a single source of revenue guidance under US GAAP for all companies in all industries. The core principle of ASU 2014-09 is that revenue should be recognized in a manner that depicts the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. ASU 2014-09 defines a five-step process in order to achieve this core principle, which may require the use of judgment and estimates. ASU 2014-09 also requires expanded qualitative and quantitative disclosures relating to the nature, amount, timing and uncertainty of revenue and cash flows arising from contracts with customers, including significant judgments and estimates used. ASU 2014-09 will be effective for the Company in the first quarter of fiscal 2017 and early adoption is not permitted. The Company may adopt ASU 2014-09 either by way of a full retrospective approach for all periods presented in the period of adoption or a modified retrospective approach. The Company is currently evaluating the impact that ASU 2014-09 will have on its financial statements and also has not yet determined which transition method it will apply.

Acquisition_of_HORIZANT_Tables

Acquisition of HORIZANT (Tables)	6 Months Ended
	Jun. 30, 2014
Assets acquired (Detail)	'
	Assets acquired as a result of this transaction were as follows (in thousands):
	Inventories	$	11,733
	Manufacturing property and equipment		1,967
	Total assets acquired	$	13,700

Net_Loss_per_Share_Tables

Net Loss per Share (Tables)	6 Months Ended
	Jun. 30, 2014
Net Loss Per Share	'
		Three Months						Six Months
		Ended June 30,						Ended June 30,
		2014			2013			2014			2013
		(In thousands, except per share amounts)
	Numerator:
	Net loss	$	(19,387	)	$	(24,381	)	$	(39,935	)	$	(47,929	)
	Denominator:
	Weighted-average common shares outstanding		61,994			47,473			59,441			47,361
	Basic and diluted net loss per share	$	(0.31	)	$	(0.51	)	$	(0.67	)	$	(1.01	)
	Outstanding securities at period end not included in the computation of diluted net loss per share as they had an anti-dilutive effect:
	Restricted stock units and options to purchase common stock		8,148			7,179			8,148			7,179
	Warrants outstanding		—			283			—			283
			8,148			7,462			8,148			7,462

Cash_and_Cash_Equivalents_Shor1

Cash and Cash Equivalents, Short-Term Investments and Restricted Investments (Tables)	6 Months Ended
	Jun. 30, 2014
Cash and Cash Equivalents, Short-Term Investments and Restricted Investments	'
	The following are summaries of cash and cash equivalents, short-term investments and restricted investments (in thousands):
		Cost		Gross		Gross			Estimated
				Unrealized		Unrealized			Fair
				Gains		Losses			Value
	As of June 30, 2014:
	Cash	$	20,777	$	—	$	—		$	20,777
	Money market funds		11,875		—		—			11,875
	Corporate debt securities		92,280		21		(7	)		92,294
	Certificates of deposit		1,725		—		—			1,725
		$	126,657	$	21	$	(7	)	$	126,671
	Reported as:
	Cash and cash equivalents								$	32,652
	Short-term investments									92,294
	Restricted investments									1,725
									$	126,671
		Cost		Gross		Gross			Estimated
				Unrealized		Unrealized			Fair
				Gains		Losses			Value
	As of December 31, 2013:
	Cash	$	2,281	$	—	$	—		$	2,281
	Money market funds		10,046		—		—			10,046
	U.S. government-sponsored agencies		2,500		—		—			2,500
	Corporate debt securities		43,831		6		(6	)		43,831
	Certificates of deposit		1,725		—		—			1,725
		$	60,383	$	6	$	(6	)	$	60,383
	Reported as:
	Cash and cash equivalents								$	20,584
	Short-term investments									38,074
	Restricted investments									1,725
									$	60,383
Available-For-Sale Investments Measured at Fair Value	'
	The Company’s available-for-sale investments, which include cash equivalents and short-term investments, are measured at fair value on a recurring basis and were classified at the following fair value hierarchy (in thousands):
	Description	Total As of		Fair Value Measurements at Reporting Date Using
		June 30,
		2014		Quoted Prices		Significant			Significant
				in Active		Other			Unobservable
				Markets		Observable			Inputs
				for Identical		Inputs			(Level 3)
				Assets		(Level 2)
				(Level 1)
	Money market funds	$	11,875	$	11,875	$	—		$	—
	Corporate debt securities		92,294		—		92,294			—
	Certificates of deposit		1,725		—		1,725			—
	Total	$	105,894	$	11,875	$	94,019		$	—
	Description	Total As of		Fair Value Measurements at Reporting Date Using
		December 31,
		2013		Quoted Prices		Significant			Significant
				in Active		Other			Unobservable
				Markets		Observable			Inputs
				for Identical		Inputs			(Level 3)
				Assets		(Level 2)
				(Level 1)
	Money market funds	$	10,046	$	10,046	$	—		$	—
	U.S. government-sponsored agencies		2,500		—		2,500			—
	Corporate debt securities		43,831		—		43,831			—
	Certificates of deposit		1,725		—		1,725			—
	Total	$	58,102	$	10,046	$	48,056		$	—

Inventories_Tables

Inventories (Tables)	6 Months Ended
	Jun. 30, 2014
Inventory	'
	Inventories as of June 30, 2014 and December 31, 2013 were as follows (in thousands):
		June 30,		December 31,
		2014		2013
	Raw materials	$	9,647	$	10,258
	Work in progress		363		76
	Finished goods		1,098		1,113
	Total inventory		11,108		11,447
	Less: Long-term inventories		9,891		10,185
	Total inventory classified as current	$	1,217	$	1,262

Other_Accrued_Liabilities_Tabl

Other Accrued Liabilities (Tables)	6 Months Ended
	Jun. 30, 2014
Other Accrued Liabilities	'
	Other accrued liabilities at June 30, 2014 and December 31, 2013 were as follows (in thousands):
		June 30,		December 31,
		2014		2013
	Accrued product costs	$	1,938	$	1,903
	Accrued selling and marketing expenses		2,068		883
	Accrued general and administrative expenses		1,365		632
	Accrued rebates, allowances and returns		504		315
	Other liabilities		310		205
	Total other accrued liabilities	$	6,185	$	3,938

StockBased_Compensation_Tables

Stock-Based Compensation (Tables)	6 Months Ended
	Jun. 30, 2014
Employee Non-Cash Stock-Based Compensation	'
	Details of the Company’s employee non-cash stock-based compensation were as follows (in thousands):
		Three Months				Six Months
		Ended June 30,				Ended June 30,
		2014		2013		2014		2013
	Research and development	$	622	$	710	$	1,324	$	1,905
	Selling, general and administrative		1,803		1,785		3,785		3,934
		$	2,425	$	2,495	$	5,109	$	5,839

Organization_and_Summary_of_Si2

Organization and Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)	6 Months Ended	12 Months Ended	0 Months Ended
	Jun. 30, 2014	Dec. 31, 2013	Jan. 29, 2014	Feb. 21, 2014
			Underwritten Public Offering	Underwriters Exercised in full Over-allotment Option
Organization And Summary Of Significant Accounting Policies [Line Items]	'	'	'	'
Annual payment for inventory of gabapentin enacarbil in GSK's possession for six years beginning in 2016	$1,000,000	$1,000,000	'	'
Common stock issued in underwritten public offering	'	'	12,000,000	1,800,000
Common stock price	'	'	$6	'
Net cash proceeds from shares offering	'	'	$67,300,000	$10,100,000

Collaboration_Arrangements_Add

Collaboration Arrangements - Additional Information (Detail) (USD $)

3 Months Ended

6 Months Ended

3 Months Ended

1 Months Ended

3 Months Ended

6 Months Ended

3 Months Ended

6 Months Ended

Jun. 30, 2014

Jun. 30, 2013

Jun. 30, 2014

Jun. 30, 2013

Dec. 31, 2013

Jun. 30, 2014

Jul. 31, 2014

14-May-14

14-May-14

14-May-14

Jun. 30, 2014

Jun. 30, 2013

Jun. 30, 2014

Jun. 30, 2013

Jun. 30, 2014

Jun. 30, 2013

Jun. 30, 2014

Jun. 30, 2013

Licensing Agreements

Licensing Agreements

Licensing Agreements

Licensing Agreements

Licensing Agreements

Licensing Agreements

Licensing Agreements

Licensing Agreements

Licensing Agreements

Licensing Agreements

Licensing Agreements

Licensing Agreements

Licensing Agreements

Reckitt Benckiser Pharmaceuticals, Inc.

Reckitt Benckiser Pharmaceuticals, Inc.

Reckitt Benckiser Pharmaceuticals, Inc.

Reckitt Benckiser Pharmaceuticals, Inc.

Reckitt Benckiser Pharmaceuticals, Inc.

Astellas Pharma Inc.

Astellas Pharma Inc.

Astellas Pharma Inc.

Astellas Pharma Inc.

Astellas Pharma Inc.

Astellas Pharma Inc.

Astellas Pharma Inc.

Astellas Pharma Inc.

Upfront, non-refundable cash payment

After delivery of certain technology and materials

Achievement of certain predefined milestones

Regulatory and development-based milestones

Commercialization-based milestones

Upfront, non-refundable cash payment

Upfront, non-refundable cash payment

Upfront, non-refundable cash payment

Upfront, non-refundable cash payment

Subsequent Event

Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Deferred revenue, initial up-front license payment received

'

'

'

'

'

$20,000,000

$5,000,000

'

'

'

'

'

'

'

'

'

'

'

Payments, maximum amount

'

'

'

'

'

'

'

120,000,000

70,000,000

50,000,000

'

'

'

'

'

'

'

'

Revenue recognized

5,334,000

2,086,000

8,709,000

2,545,000

'

'

'

'

'

'

'

'

'

'

283,000

379,000

566,000

758,000

Royalty revenue

131,000

67,000

266,000

147,000

'

'

'

'

'

'

131,000

67,000

266,000

147,000

'

'

'

'

Aggregate revenue recognized

'

'

'

'

'

'

'

'

'

'

53,210,000

'

53,210,000

'

'

'

'

'

Deferred revenue

'

'

'

'

'

'

'

'

'

'

12,565,000

'

12,565,000

'

'

'

'

'

Deferred revenue, current

21,135,000

'

21,135,000

'

1,134,000

'

'

'

'

'

1,135,000

'

1,135,000

'

'

'

'

'

Deferred revenue, non-current

$11,430,000

'

$11,430,000

'

$11,997,000

'

'

'

'

'

$11,430,000

'

$11,430,000

'

'

'

'

'

Assets_Acquired_Detail

Assets Acquired (Detail) (Horizant Business, USD $)	1-May-13
In Thousands, unless otherwise specified
Horizant Business	'
Business Acquisition [Line Items]	'
Inventories	$11,733
Manufacturing property and equipment	1,967
Total assets acquired	$13,700

Net_Loss_Per_Share_Detail

Net Loss Per Share (Detail) (USD $)	3 Months Ended		6 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Numerator:	'	'	'	'
Net loss	($19,387)	($24,381)	($39,935)	($47,929)
Denominator:	'	'	'	'
Weighted-average common shares outstanding	61,994	47,473	59,441	47,361
Basic and diluted net loss per share	($0.31)	($0.51)	($0.67)	($1.01)
Outstanding securities at period end not included in the computation of diluted net loss per share as they had an anti-dilutive effect:	'	'	'	'
Outstanding securities not included in the computation of diluted net loss per share	8,148	7,462	8,148	7,462
Restricted stock units and options to purchase common stock	'	'	'	'
Outstanding securities at period end not included in the computation of diluted net loss per share as they had an anti-dilutive effect:	'	'	'	'
Outstanding securities not included in the computation of diluted net loss per share	8,148	7,179	8,148	7,179
Warrants outstanding	'	'	'	'
Outstanding securities at period end not included in the computation of diluted net loss per share as they had an anti-dilutive effect:	'	'	'	'
Outstanding securities not included in the computation of diluted net loss per share	'	283	'	283

Cash_and_Cash_Equivalents_Shor2

Cash and Cash Equivalents, Short-Term Investments and Restricted Investments (Detail) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Cash Cash Equivalents Short Term Investments and Restricted Investments [Line Items]	'	'
Cost	$126,657	$60,383
Gross Unrealized Gains	21	6
Gross Unrealized Losses	-7	-6
Estimated Fair Value	126,671	60,383
U.S. government-sponsored agencies	'	'
Cash Cash Equivalents Short Term Investments and Restricted Investments [Line Items]	'	'
Cost	'	2,500
Estimated Fair Value	'	2,500
Corporate debt securities	'	'
Cash Cash Equivalents Short Term Investments and Restricted Investments [Line Items]	'	'
Cost	92,280	43,831
Gross Unrealized Gains	21	6
Gross Unrealized Losses	-7	-6
Estimated Fair Value	92,294	43,831
Certificates of deposit	'	'
Cash Cash Equivalents Short Term Investments and Restricted Investments [Line Items]	'	'
Cost	1,725	1,725
Estimated Fair Value	1,725	1,725
Short-term investments	'	'
Cash Cash Equivalents Short Term Investments and Restricted Investments [Line Items]	'	'
Estimated Fair Value	92,294	38,074
Restricted investments	'	'
Cash Cash Equivalents Short Term Investments and Restricted Investments [Line Items]	'	'
Estimated Fair Value	1,725	1,725
Cash	'	'
Cash Cash Equivalents Short Term Investments and Restricted Investments [Line Items]	'	'
Cost	20,777	2,281
Estimated Fair Value	20,777	2,281
Money market funds	'	'
Cash Cash Equivalents Short Term Investments and Restricted Investments [Line Items]	'	'
Cost	11,875	10,046
Estimated Fair Value	11,875	10,046
Cash and cash equivalents	'	'
Cash Cash Equivalents Short Term Investments and Restricted Investments [Line Items]	'	'
Estimated Fair Value	$32,652	$20,584

Cash_and_Cash_Equivalents_Shor3

Cash and Cash Equivalents, Short-Term Investments and Restricted Investments - Additional Information (Detail) (USD $)	3 Months Ended		6 Months Ended			12 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Dec. 31, 2013
					Maximum	Maximum
Cash Cash Equivalents Short Term Investments and Restricted Investments [Line Items]	'	'	'	'	'	'
Contractual maturities of investments held	'	'	'	'	'17 months	'1 year
Gross realized gains or losses recognized	$0	$0	$0	$0	'	'
Amounts reclassified out of accumulated other comprehensive loss to earnings	$0	$0	$0	$0	'	'

AvailableForSale_Investments_M

Available-For-Sale Investments Measured at Fair Value (Detail) (Fair Value Measurements, Recurring basis, USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale investments	$105,894	$58,102
Money market funds	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale investments	11,875	10,046
U.S. government-sponsored agencies	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale investments	'	2,500
Corporate debt securities	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale investments	92,294	43,831
Certificates of deposit	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale investments	1,725	1,725
Quoted Prices in Active Markets for Identical Assets (Level 1)	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale investments	11,875	10,046
Quoted Prices in Active Markets for Identical Assets (Level 1) | Money market funds	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale investments	11,875	10,046
Significant Other Observable Inputs (Level 2)	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale investments	94,019	48,056
Significant Other Observable Inputs (Level 2) | U.S. government-sponsored agencies	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale investments	'	2,500
Significant Other Observable Inputs (Level 2) | Corporate debt securities	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale investments	92,294	43,831
Significant Other Observable Inputs (Level 2) | Certificates of deposit	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale investments	$1,725	$1,725

Inventory_Detail

Inventory (Detail) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Inventory [Line Items]	'	'
Raw materials	$9,647	$10,258
Work in progress	363	76
Finished goods	1,098	1,113
Total inventory	11,108	11,447
Less: Long-term inventories	9,891	10,185
Total inventory classified as current	1,217	1,262
Total inventory	$11,108	$11,447

Other_Accrued_Liabilities_Deta

Other Accrued Liabilities (Detail) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Other Accrued Liabilities [Line Items]	'	'
Accrued product costs	$1,938	$1,903
Accrued selling and marketing expenses	2,068	883
Accrued general and administrative expenses	1,365	632
Accrued rebates, allowances and returns	504	315
Other liabilities	310	205
Total other accrued liabilities	$6,185	$3,938

Employee_NonCash_StockBased_Co

Employee Non-Cash Stock-Based Compensation (Detail) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'	'	'
Non-cash stock-based compensation	$2,425	$2,495	$5,109	$5,839
Research and development	'	'	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'	'	'
Non-cash stock-based compensation	622	710	1,324	1,905
Selling, general and administrative	'	'	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'	'	'
Non-cash stock-based compensation	$1,803	$1,785	$3,785	$3,934

Stockholders_Equity_Additional

Stockholders Equity - Additional Information (Detail)	6 Months Ended
	Jun. 30, 2014
2014 Equity Incentive Plan	'
Stockholders Equity Note [Line Items]	'
Equity Incentive Plans, shares available for issuance	4,471,059
Equity Incentive Plans, additional shares available for issuance	7,847,852
Stock Incentive Plan 1999 | Minimum	'
Stockholders Equity Note [Line Items]	'
Equity Incentive Plans, option exercise prices as a percentage of fair value of common stock	100.00%