Alnylam Pharmaceuticals (ALNY) 10-Q 8 Aug 14 2014 Q2 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	6 Months Ended
	Jun. 30, 2014	Jul. 31, 2014
Document Information [Line Items]	'	'
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	'ALNY	'
Entity Registrant Name	'ALNYLAM PHARMACEUTICALS, INC.	'
Entity Central Index Key	'0001178670	'
Current Fiscal Year End Date	'--12-31	'
Entity Filer Category	'Large Accelerated Filer	'
Entity Common Stock, Shares Outstanding	'	76,354,817

Condensed_Consolidated_Balance

Condensed Consolidated Balance Sheets (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Current assets:	'	'
Cash and cash equivalents	$80,727	$53,169
Marketable securities	524,585	192,701
Investment in equity securities of Regulus Therapeutics Inc.	49,450	'
Billed and unbilled collaboration receivables	89	4,248
Prepaid expenses and other current assets	10,270	3,910
Total current assets	665,121	254,028
Marketable securities	350,585	104,602
Investment in equity securities of Regulus Therapeutics Inc.	'	45,452
Property and equipment, net	16,953	16,448
Total assets	1,032,659	420,530
Current liabilities:	'	'
Accounts payable	6,168	5,896
Accrued expenses	15,783	14,160
Accrued intraperiod tax allocation	4,081	'
Deferred rent	711	1,112
Deferred revenue	27,002	32,696
Total current liabilities	53,745	53,864
Deferred rent, net of current portion	3,097	2,925
Deferred revenue, net of current portion	32,548	93,394
Other liabilities	1,000	'
Total liabilities	90,390	150,183
Commitments and contingencies (Note 3)	'	'
Stockholders' equity:	'	'
Preferred stock, $0.01 par value per share, 5,000,000 shares authorized and no shares issued and outstanding at June 30, 2014 and December 31, 2013	'	'
Common stock, $0.01 par value per share, 125,000,000 shares authorized; 76,324,130 shares issued and outstanding at June 30, 2014; 63,741,573 shares issued and outstanding at December 31, 2013	763	637
Additional paid-in capital	1,810,775	846,228
Accumulated other comprehensive income	21,983	19,717
Accumulated deficit	-891,252	-596,235
Total stockholders' equity	942,269	270,347
Total liabilities and stockholders' equity	$1,032,659	$420,530

Condensed_Consolidated_Balance1

Condensed Consolidated Balance Sheets (Parenthetical) (USD $)	Jun. 30, 2014	Dec. 31, 2013
Preferred stock, par value	$0.01	$0.01
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	$0.01	$0.01
Common stock, shares authorized	125,000,000	125,000,000
Common stock, shares issued	76,324,130	63,741,573
Common stock, shares outstanding	76,324,130	63,741,573

Condensed_Consolidated_Stateme

Condensed Consolidated 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
Net revenues from collaborators	$7,295		$8,687		$15,570		$27,329
Operating expenses:	'		'		'		'
Research and development	44,672	[1]	24,215	[1]	88,430	[1]	46,394	[1]
In-process research and development	-3,890		'		220,766		'
General and administrative	11,518	[1]	5,784	[1]	20,443	[1]	12,051	[1]
Total operating expenses	52,300		29,999		329,639		58,445
Loss from operations	-45,005		-21,312		-314,069		-31,116
Other income (expense):	'		'		'		'
Interest income	693		270		1,026		494
Other expense	-77		-11		-159		-6
Total other income	616		259		867		488
Loss before income taxes	-44,389		-21,053		-313,202		-30,628
Benefit from income taxes	315		2,884		18,185		3,446
Net loss	-44,074		-18,169		-295,017		-27,182
Net loss per common share - basic and diluted	($0.58)		($0.29)		($4.11)		($0.45)
Weighted average common shares used to compute basic and diluted net loss per common share	75,835		61,661		71,833		60,424
Comprehensive loss:	'		'		'		'
Net loss	-44,074		-18,169		-295,017		-27,182
Unrealized (loss) gain on marketable securities, net of tax	-3,047		7,309		2,266		12,468
Comprehensive loss	($47,121)		($10,860)		($292,751)		($14,714)
[1]	Non-cash stock-based compensation expenses included in operating expenses are as follows: Research and development $ 2,557 $ 2,200 $ 6,238 $ 4,287 General and administrative 5,123 1,177 7,033 2,165

Condensed_Consolidated_Stateme1

Condensed Consolidated Statements of Comprehensive Loss (Parenthetical) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Non-cash stock-based compensation expenses included in operating expenses are as follows:	'	'	'	'
Non-cash stock-based compensation	'	'	$13,271	$6,452
Research and Development Expense	'	'	'	'
Non-cash stock-based compensation expenses included in operating expenses are as follows:	'	'	'	'
Non-cash stock-based compensation	2,557	2,200	6,238	4,287
General and Administrative Expense	'	'	'	'
Non-cash stock-based compensation expenses included in operating expenses are as follows:	'	'	'	'
Non-cash stock-based compensation	$5,123	$1,177	$7,033	$2,165

Condensed_Consolidated_Stateme2

Condensed Consolidated Statements of Cash Flows (USD $)	6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013
Cash flows from operating activities:	'	'
Net loss	($295,017)	($27,182)
Adjustments to reconcile net loss to net cash used in operating activities:	'	'
Depreciation and amortization	5,468	4,838
Non-cash stock-based compensation	13,271	6,452
Charge for 401(k) company stock match	332	247
Benefit from intraperiod tax allocation	-18,185	-3,446
In-process research and development	220,766	'
Changes in operating assets and liabilities:	'	'
Proceeds from landlord tenant improvements	'	192
Billed and unbilled collaboration receivables	4,159	-356
Prepaid expenses and other assets	-6,360	-1,650
Accounts payable	121	470
Accrued expenses and other	2,235	-3,043
Deferred revenue	-15,090	-1,095
Net cash used in operating activities	-88,300	-24,573
Cash flows from investing activities:	'	'
Purchases of property and equipment	-2,240	-2,178
Purchases of marketable securities	-768,510	-274,428
Sales and maturities of marketable securities	187,595	92,557
Payment for asset acquisition	-25,000	'
Net cash used in investing activities	-608,155	-184,049
Cash flows from financing activities:	'	'
Proceeds from exercise of stock options and other types of equity	16,679	8,620
Proceeds from issuance of common stock, net of offering costs	'	173,572
Proceeds from issuance of common stock to Genzyme	723,037	'
Payments for repurchase of common stock for employee tax withholding	-15,703	'
Net cash provided by financing activities	724,013	182,192
Net increase (decrease) in cash and cash equivalents	27,558	-26,430
Cash and cash equivalents, beginning of period	53,169	51,405
Cash and cash equivalents, end of period	$80,727	$24,975

SUMMARY_OF_SIGNIFICANT_ACCOUNT

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	6 Months Ended
	Jun. 30, 2014
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	'
	1. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
	Basis of Presentation and Principles of Consolidation
	The accompanying condensed consolidated financial statements of Alnylam Pharmaceuticals, Inc. are unaudited and have been prepared in accordance with accounting principles generally accepted in the United States of America, or GAAP, applicable to interim periods and, in the opinion of management, include all normal and recurring adjustments that are necessary to state fairly the results of operations for the reported periods. Our condensed consolidated financial statements have also been prepared on a basis substantially consistent with, and should be read in conjunction with, our audited consolidated financial statements for the year ended December 31, 2013, which were included in our Annual Report on Form 10-K that was filed with the Securities and Exchange Commission, or SEC, on February 20, 2014. The year-end condensed consolidated balance sheet data was derived from our audited financial statements, but does not include all disclosures required by GAAP. The results of our operations for any interim period are not necessarily indicative of the results of our operations for any other interim period or for a full fiscal year.
	The accompanying condensed consolidated financial statements reflect the operations of Alnylam and our wholly-owned subsidiaries. All significant intercompany accounts and transactions have been eliminated.
	Use of Estimates
	The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.
	Net Loss Per Common Share
	We compute basic net loss per common share by dividing net loss by the weighted average number of common shares outstanding. We compute diluted net loss per common share by dividing net loss by the weighted average number of common shares and dilutive potential common share equivalents then outstanding. Potential common shares consist of shares issuable upon the exercise of stock options (using the treasury stock method) and unvested restricted stock awards. Because the inclusion of potential common shares would be anti-dilutive for all periods presented, diluted net loss per common share is the same as basic net loss per common share.
	The following table sets forth for each period presented the potential common shares (prior to consideration of the treasury stock method) excluded from the calculation of net loss per common share because their inclusion would be anti-dilutive, in thousands:
		At June 30,
		2014			2013
	Options to purchase common stock		8,038			8,567
	Unvested restricted common stock		23			604
			8,061			9,171
	Public Offering
	In January 2013, we sold an aggregate of 9,200,000 shares of our common stock through an underwritten public offering at a price to the public of $20.13 per share. As a result of this offering, we received aggregate net proceeds of $173.6 million, after deducting underwriting discounts and commissions and other offering expenses of $11.6 million.
	Fair Value Measurements
	The fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. The following tables present information about our assets that are measured at fair value on a recurring basis at June 30, 2014 and December 31, 2013, and indicate the fair value hierarchy of the valuation techniques we utilized to determine such fair value. In general, fair values determined by Level 1 inputs utilize quoted prices (unadjusted) in active markets for identical assets or liabilities. Fair values determined by Level 2 inputs utilize data points that are observable, such as quoted prices (adjusted), interest rates and yield curves. Fair values determined by Level 3 inputs utilize unobservable data points for the asset or liability, and include situations where there is little, if any, market activity for the asset or liability. The fair value hierarchy level is determined by the lowest level of significant input. Financial assets measured at fair value on a recurring basis are summarized as follows, in thousands:
	Description	At			Quoted Prices			Significant			Significant
		June 30,			in Active			Observable			Unobservable
		2014			Markets			Inputs			Inputs
					(Level 1)			(Level 2)			(Level 3)
	Cash equivalents	$	70,110		$	57,920		$	12,190		$	—
	Marketable securities (fixed income):
	Corporate notes		644,353			—			644,353			—
	U.S. government-sponsored enterprise securities		59,638			—			59,638			—
	Municipal debt securities		9,031			—			9,031			—
	Commercial paper		162,148			—			162,148			—
	Marketable securities (Regulus equity holdings)		49,450			49,450			—			—
	Total	$	994,730		$	107,370		$	887,360		$	—
	Description	At			Quoted Prices			Significant			Significant
		December 31,			in Active			Observable			Unobservable
		2013			Markets			Inputs			Inputs
					(Level 1)			(Level 2)			(Level 3)
	Cash equivalents	$	32,571		$	32,571		$	—		$	—
	Marketable securities (fixed income):
	Corporate notes		228,462			—			228,462			—
	U.S. government-sponsored enterprise securities		56,863			—			56,863			—
	Commercial paper		11,978			—			11,978			—
	Marketable securities (Regulus equity holdings)		45,452			45,452			—			—
	Total	$	375,326		$	78,023		$	297,303		$	—
	During the six months ended June 30, 2014, there were no transfers between Level 1 and Level 2 financial assets. The carrying amounts reflected in our condensed consolidated balance sheets for cash, billed and unbilled collaboration receivables, other current assets, accounts payable, and accrued expenses approximate fair value due to their short-term maturities.
	Investments in Marketable Securities
	We invest our excess cash balances in short-term and long-term marketable debt and equity securities. We classify our investments in marketable debt securities as either held-to-maturity or available-for-sale based on facts and circumstances present at the time we purchased the securities. At each balance sheet date presented, we classified all of our investments in debt and equity securities as available-for-sale. We report available-for-sale investments at fair value at each balance sheet date and include any unrealized holding gains and losses (the adjustment to fair value) in accumulated other comprehensive income (loss), a component of stockholders’ equity. At June 30, 2014, the balance in our accumulated other comprehensive income was composed solely of activity related to our available-for-sale marketable securities, including our investment in equity securities of Regulus Therapeutics Inc., or Regulus. Realized gains and losses are determined using the specific identification method and are included in other income. We did not recognize any realized gains or losses from sales of our available-for-sale securities during the six months ended June 30, 2014, and as a result, did not reclassify any amount out of accumulated other comprehensive income for the same period. If any adjustment to fair value reflects a decline in the value of the investment, we consider all available evidence to evaluate the extent to which the decline is “other than temporary” and, if so, mark the investment to market through a charge to our condensed consolidated statements of comprehensive income (loss). We did not record any impairment charges related to our fixed income marketable securities during the current period. Our marketable securities are classified as cash equivalents if the original maturity, from the date of purchase, is 90 days or less, and as marketable securities if the original maturity, from the date of purchase, is in excess of 90 days. Our cash equivalents are composed of money market funds and corporate notes.
	In the fourth quarter of 2012, we began accounting for our investment in Regulus as an available-for-sale marketable security. Intraperiod tax allocation rules require us to allocate our provision for income taxes between continuing operations and other categories of earnings, such as other comprehensive income. In periods in which we have a year-to-date pre-tax loss from continuing operations and pre-tax income in other categories of earnings, such as other comprehensive income, we must allocate the tax provision to the other categories of earnings. We then record a related tax benefit in continuing operations.
	The following tables summarize the fair value, accumulated other comprehensive income and intraperiod tax allocation regarding our investment in Regulus available-for-sale marketable securities at June 30, 2014 and 2013 and the activity for the three months ended June 30, 2014 and 2013, in thousands:
	Description	At			Three			Balance at
		March 31,			Months Ended			June 30, 2014
		2014			30-Jun-14
	Carrying value	$	12,449		$	—		$	12,449
	Accumulated other comprehensive income, before tax		43,029			(6,028	)		37,001
	Investment in equity securities of Regulus, as reported	$	55,478		$	(6,028	)	$	49,450
	Accumulated other comprehensive income, before tax	$	43,029		$	(6,028	)	$	37,001
	Intraperiod tax allocation recorded as a benefit from income taxes		(15,966	)		1,384			(14,582	)
	Intraperiod tax allocation recorded as an accrued liability		(1,380	)		1,088			(292	)
	Accumulated other comprehensive income, net of tax	$	25,683		$	(3,556	)	$	22,127
	Description	At			Three			Balance at
		March 31,			Months Ended			June 30, 2013
		2013			June 30, 2013
	Carrying value	$	12,449		$	—		$	12,449
	Accumulated other comprehensive income, before tax		35,217			12,670			47,887
	Investment in equity securities of Regulus, as reported	$	47,666		$	12,670		$	60,336
	Accumulated other comprehensive income, before tax	$	35,217		$	12,670		$	47,887
Intraperiod tax allocation recorded as a benefit from income taxes		(11,134	)		(2,884	)		(14,018	)
Intraperiod tax allocation recorded as an accrued liability		(3,023	)		(2,209	)		(5,232	)
Accumulated other comprehensive income, net of tax	$	21,060		$	7,577		$	28,637
The following tables summarize the fair value, accumulated other comprehensive income and intraperiod tax allocation regarding our investment in Regulus available-for-sale marketable securities at June 30, 2014 and 2013 and the activity for the six months ended June 30, 2014 and 2013, in thousands:
Description	At			Six			Balance at
	December 31,			Months Ended			June 30, 2014
	2013			30-Jun-14
Carrying value	$	12,449		$	—		$	12,449
Accumulated other comprehensive income, before tax		33,003			3,998			37,001
Investment in equity securities of Regulus, as reported	$	45,452		$	3,998		$	49,450
Accumulated other comprehensive income, before tax	$	33,003		$	3,998		$	37,001
Intraperiod tax allocation recorded as a benefit from income taxes		(13,267	)		(1,315	)		(14,582	)
Intraperiod tax allocation recorded as an accrued liability		—			(292	)		(292	)
Accumulated other comprehensive income, net of tax	$	19,736		$	2,391		$	22,127
Description	At			Six			Balance at
	December 31,			Months Ended			June 30, 2013
	2012			30-Jun-13
Carrying value	$	12,449		$	—		$	12,449
Accumulated other comprehensive income, before tax		26,299			21,588			47,887
Investment in equity securities of Regulus, as reported	$	38,748		$	21,588		$	60,336
Accumulated other comprehensive income, before tax	$	26,299		$	21,588		$	47,887
Intraperiod tax allocation recorded as a benefit from income taxes		(10,572	)		(3,446	)		(14,018	)
Intraperiod tax allocation recorded as an accrued liability		—			(5,232	)		(5,232	)
Accumulated other comprehensive income, net of tax	$	15,727		$	12,910		$	28,637
We obtain fair value measurement data for our marketable securities from independent pricing services. We perform validation procedures to ensure the reasonableness of this data. This includes meeting with the independent pricing services to understand the methods and data sources used. Additionally, we perform our own review of prices received from the independent pricing services by comparing these prices to other sources and confirming those securities are trading in active markets.
The following tables summarize our marketable securities, other than our holdings in Regulus noted above, at June 30, 2014 and December 31, 2013, in thousands:
	At June 30, 2014
Description	Amortized			Gross			Gross			Fair Value
	Cost			Unrealized			Unrealized
				Gains			Losses
Commercial paper (Due within 1 year)	$	162,170		$	4		$	(26	)	$	162,148
Corporate notes (Due within 1 year)		347,396			101			(67	)		347,430
Corporate notes (Due after 1 year through 2 years)		297,086			70			(233	)		296,923
U.S. government-sponsored enterprise securities (Due within 1 year)		15,001			6			—			15,007
U.S. government-sponsored enterprise securities (Due after 1 year through 2 years)		44,658			2			(29	)		44,631
Municipal debt securities (Due after 1 year through 2 years)		9,003			28			—			9,031
Total	$	875,314		$	211		$	(355	)	$	875,170
	At December 31, 2013
Description	Amortized			Gross			Gross			Fair Value
	Cost			Unrealized			Unrealized
				Gains			Losses
Commercial paper (Due within 1 year)	$	11,983		$	—		$	(5	)	$	11,978
Corporate notes (Due within 1 year)		154,175			33			(46	)		154,162
Corporate notes (Due after 1 year through 2 years)		74,312			23			(35	)		74,300
U.S. government-sponsored enterprise securities (Due within 1 year)		26,553			8			—			26,561
U.S. government-sponsored enterprise securities (Due after 1 year through 2 years)		30,300			2			—			30,302
Total	$	297,323		$	66		$	(86	)	$	297,303
Recent Accounting Pronouncements
In May 2014, the Financial Accounting Standards Board, or FASB, issued a new revenue recognition standard which amends revenue recognition principles and provides a single, comprehensive set of criteria for revenue recognition within and across all industries. The new standard provides a five step framework whereby revenue is recognized when promised goods or services are transferred to a customer at an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The standard also requires enhanced disclosures pertaining to revenue recognition in both interim and annual periods. For public companies, the standard is effective for interim and annual reporting periods beginning after December 15, 2016. Early adoption is not permitted. The standard allows for adoption using a full retrospective method or a modified retrospective method. We are currently evaluating the method of adoption and the expected impact that the standard could have on our condensed consolidated financial statements and related disclosures.

SIGNIFICANT_AGREEMENTS

SIGNIFICANT AGREEMENTS	6 Months Ended
	Jun. 30, 2014
SIGNIFICANT AGREEMENTS	'
	2. SIGNIFICANT AGREEMENTS
	The following table summarizes our total consolidated net revenues from collaborators, for the periods indicated, in thousands:
			Three Months Ended June 30,				Six Months Ended June 30,
			2014		2013		2014		2013
	Takeda		$	5,494	$	5,494	$	10,987	$	10,987
	Monsanto			1,410		1,410		2,820		2,820
	Cubist			—		—		—		9,721
	Other			391		1,783		1,763		3,801
	Total net revenues from collaborators		$	7,295	$	8,687	$	15,570	$	27,329
	Product Alliances
	Genzyme Collaboration
	In January 2014, we entered into a global, strategic collaboration with Genzyme Corporation, a Sanofi company, or Genzyme, to discover, develop and commercialize RNA interference, or RNAi, therapeutics as genetic medicines to treat orphan diseases. The 2014 Genzyme collaboration is governed by a master collaboration agreement, dated January 11, 2014, by and between us and Genzyme, which became effective in February 2014 upon the closing of the equity transaction, described below. The master agreement superseded and replaced the previous collaboration between us and Genzyme entered into in October 2012 to develop and commercialize RNAi therapeutics targeting transthyretin, or TTR, for the treatment of transthyretin-mediated amyloidosis, or ATTR, including patisiran (ALN-TTR02) and ALN-TTRsc.
	2012 Genzyme Agreement
	In consideration for the rights granted to Genzyme under the 2012 Genzyme agreement, Genzyme paid us an upfront cash payment of $22.5 million. We were also entitled to receive certain milestone payments under the 2012 Genzyme agreement. In the fourth quarter of 2013, we earned a milestone of $7.0 million based upon the completion of a successful patisiran Phase 2 clinical trial and a milestone of $4.0 million based upon the initiation of the Phase 3 clinical trial for patisiran.
	Under the 2012 Genzyme agreement, the parties agreed to collaborate in the development of licensed products, with Genzyme assuming primary responsibility for the development and commercialization of licensed products in the Genzyme territory, which included Japan and the Asia-Pacific region, and us retaining primary responsibility for the development and commercialization of licensed products in the rest of the world. The collaboration between Genzyme and us was governed by a joint steering committee comprised of an equal number of representatives from each party. Genzyme was responsible, at its expense, for all development activities under the development plan reasonably necessary for the regulatory approval and commercialization of an RNAi therapeutic for the treatment of ATTR in the Genzyme territory.
	We determined that the deliverables under the 2012 Genzyme agreement included the license, the joint steering committee and any additional TTR-specific RNAi therapeutic compounds that comprised the ALN-TTR program. We also determined that, pursuant to the accounting guidance governing revenue recognition on multiple element arrangements, the license and undelivered joint steering committee and any additional TTR-specific RNAi therapeutic compounds did not have standalone value due to the specialized nature of the services to be provided by us. In addition, while Genzyme had the ability to grant sublicenses, it could not sublicense all or substantially all of its rights under the 2012 Genzyme agreement. The uniqueness of our services and the limited sublicense right were indicators that standalone value was not present in the arrangement. Therefore the deliverables were not separable and, accordingly, the license and undelivered services were treated as a single unit of account. We were unable to reasonably estimate the period of performance under the 2012 Genzyme agreement, as we were unable to estimate the timeline of our deliverables related to the deliverable for any additional TTR-specific RNAi therapeutic compounds. Through December 31, 2013, we had deferred all revenue, or $33.5 million, under the 2012 Genzyme agreement.
	2014 Genzyme Collaboration
	In January 2014, we entered into the 2014 Genzyme collaboration. As noted above, the 2014 Genzyme collaboration is governed by a master agreement, which became effective upon the closing of the equity transaction in February 2014 and superseded and replaced the 2012 Genzyme agreement.
	The 2014 Genzyme collaboration is structured as an exclusive relationship for the worldwide development and commercialization of RNAi therapeutics in the field of genetic medicines, which includes our current and future genetic medicine programs that reach human proof-of-principal study completion, or Human POP, by the end of 2019, subject to extension to the end of 2021 in various circumstances. We will retain product rights in North America and Western Europe, referred to as the Alnylam Territory, while Genzyme will obtain exclusive rights to develop and commercialize collaboration products in the rest of the world, referred to as the Genzyme Territory, together with certain broader co-development/co-promote or worldwide rights for certain products. Genzyme’s rights, described in detail below, are structured as an opt-in that is triggered upon achievement of Human POP. We maintain development control for all programs prior to Genzyme’s opt-in and maintain development and commercialization control after Genzyme’s opt-in for all programs in the Alnylam Territory.
	Specifically, in addition to its regional rights for our current and future genetic medicine programs in the Genzyme Territory, Genzyme will have the right to either (i) co-develop and co-promote ALN-AT3 for the treatment of hemophilia and other rare bleeding disorders in the Alnylam Territory, with us maintaining development and commercialization control, or (ii) obtain a global license to ALN-AS1 for the treatment of hepatic porphyrias. Genzyme will exercise this selection right upon the completion of Human POP for both the ALN-AT3 and ALN-AS1 programs. Finally, Genzyme will have the right for a global license to a single, future genetic medicine program that is not one of our currently defined genetic medicine programs. We will retain global rights to any RNAi therapeutic genetic medicine program that does not reach Human POP by the end of 2019, subject to certain limited exceptions. Under the terms of the master agreement, we retain full rights to all current and future RNAi therapeutic programs outside of the field of genetic medicines, including the right to form new collaborations.
	Under the 2014 Genzyme collaboration, Genzyme’s specific license rights include the following:
		•		Regional license terms – Upon opt-in, Alnylam will retain product rights in the Alnylam Territory, while Genzyme will obtain exclusive rights to develop and commercialize the product in the Genzyme Territory. Genzyme can elect this license for any of Alnylam’s current and future genetic medicine programs that complete Human POP by the end of 2019, subject to limited extension. Development costs for products once Genzyme exercises an option will be shared between Genzyme and us, with Genzyme responsible for twenty percent of the global development costs. Upon the effective date of the 2014 Genzyme collaboration, Genzyme expanded the scope of its regional license and collaboration for patisiran, an RNAi therapeutic currently in a Phase 3 clinical trial for the treatment of ATTR patients with familial amyloidotic polyneuropathy, or FAP, which was originally established under the 2012 Genzyme agreement. In consideration for the rights granted to Genzyme under the regional license and collaboration terms for patisiran, Genzyme will be required to make payments totaling up to $50.0 million upon the achievement of certain development milestones. In addition, Genzyme will be required to make payments totaling up to $75.0 million per product other than patisiran, including up to $55.0 million in development milestones and $20.0 million in commercial milestones. Genzyme will also be required to pay tiered double-digit royalties up to twenty percent for each regional product based on annual net sales, if any, of such regional product by Genzyme, its affiliates and sublicensees.
		•		Co-development/co-promote license terms - Upon opt-in, Alnylam will retain product rights in the Alnylam Territory, while Genzyme will obtain exclusive rights to develop and commercialize the product in the Genzyme Territory, and will co-promote the product in the Alnylam Territory. Upon the effective date of the 2014 Genzyme collaboration, Genzyme expanded its regional rights for ALN-TTRsc, an RNAi therapeutic currently in a Phase 2 clinical trial for the treatment of ATTR patients with TTR amyloid cardiomyopathy, which were originally granted under the 2012 Genzyme agreement, to include a co-development/co-promote license and collaboration. Genzyme also has the right to elect a co-development/co-promote license and collaboration for ALN-AT3, if they do not elect a global license and collaboration for ALN-AS1. Development costs for co-development/co-promote products, once Genzyme exercises an option, will be shared between Genzyme and us, with Genzyme responsible for fifty percent of the global development costs. In consideration for the rights granted to Genzyme under the co-development/co-promote license terms, Genzyme will be required to make payments totaling up to $75.0 million in development milestones for each of ALN-TTRsc and ALN-AT3, if selected. We could potentially earn the next development milestone payment of $25.0 million under the 2014 Genzyme collaboration based upon the initiation of the first global Phase 3 clinical trial for ALN-TTRsc. Genzyme will also be required to pay tiered double-digit royalties up to twenty percent for each co-development/co-promote product based on annual net sales, if any, in the Genzyme Territory for such co-development/co-promote product by Genzyme, its affiliates and sublicensees. The parties will share profits equally and we will book product sales in the Alnylam Territory.
		•		Global license terms – Upon opt-in, Genzyme will obtain a worldwide license to develop and commercialize the product. Genzyme can elect a global license for ALN-AS1, if they do not elect a co-development/co-promote license for ALN-AT3. Genzyme will also have one right to a global license through 2019, subject to limited extension, for a future genetic medicine program that is not one of our currently defined genetic medicine programs. Genzyme shall be responsible for one hundred percent of global development costs. In consideration for the rights granted to Genzyme under the global license terms, Genzyme will be required to make payments totaling up to $200.0 million per product, including up to $60.0 million in development milestones and $140.0 million in commercial milestones. Genzyme will also be required to pay tiered double-digit royalties up to twenty percent for each global product based on annual net sales, if any, of each global product by Genzyme, its affiliates and sublicensees.
	Under the master agreement, the parties will collaborate in the development of option products, with us leading development for all programs prior to Genzyme’s opt-in and also leading development and commercialization for all programs in the Alnylam Territory after Genzyme’s opt-in. If Genzyme does not exercise its option to license rights to a particular program, we will retain the exclusive right to develop and commercialize such program throughout the world, including the right to sublicense to third parties.
	The 2014 Genzyme collaboration is governed by an alliance joint steering committee that is comprised of an equal number of representatives from each party. There will also be additional committees to manage various aspects of each regional, co-developed/co-promoted and global program. We and Genzyme intend to enter into supply agreements to provide for supply of collaboration products to Genzyme for clinical studies, and, at Genzyme’s request, commercial sales. Genzyme also has certain rights to manufacture collaboration products. Additionally, Genzyme has certain limited opt-out rights, as specified in the master agreement, upon which products revert fully back to us with no further obligations to Genzyme.
	In consideration for the rights granted to Genzyme under the master agreement and pursuant to the terms of a stock purchase agreement dated January 11, 2014, upon the closing of the equity transaction in February 2014, we sold to Genzyme 8,766,338 shares of our common stock and Genzyme paid $700.0 million in aggregate cash consideration to us. We recorded this issuance using the price of our common stock on the date the shares were issued to Genzyme. Based on the common stock price of $85.72, the fair value of the shares issued was $751.5 million, which was $51.5 million in excess of the proceeds received from Genzyme for the issuance of our common stock. This $51.5 million is being amortized on a straight line basis over the performance period, which is currently five years as described below. In addition, due to intraperiod tax allocation rules, upon closing of the equity transaction we recorded a benefit from income taxes of $15.2 million due to the Genzyme equity purchase being recorded in additional paid-in capital, net of tax.
	As a condition to the closing of the equity transaction, Genzyme entered into an investor agreement with us. Under the investor agreement, until the earlier of the fifth anniversary of the expiration or earlier termination of the 2014 Genzyme collaboration and the date on which Genzyme and its affiliates cease to beneficially own at least 5% of our outstanding common stock, Genzyme and its affiliates are bound by certain “standstill” provisions. The standstill provisions include agreements not to acquire more than 30% of our outstanding common stock, call stockholder meetings, nominate directors other than those approved by our board of directors, subject to certain limited exceptions, or propose or support a proposal to acquire us.
	Further, Genzyme has agreed to vote, and cause its affiliates to vote, all shares of our voting securities they are entitled to vote, up to a maximum of 20% of our outstanding common stock, in a manner either as recommended by our board of directors or proportionally with the votes cast by our other stockholders, except with respect to certain change of control transactions or our liquidation or dissolution. Until Genzyme owns less than 7.5% of our outstanding common stock, subject to Genzyme’s limited right to maintain its ownership percentage as described below, if we issue common stock or securities convertible into or exercisable for common stock to a third party that holds at least 30% of our outstanding common stock or, in connection with a collaboration or license transaction, to a third party that will initially hold at least the percentage of our outstanding common stock represented by the shares purchased by Genzyme at the closing of the equity transaction, we will offer Genzyme an opportunity to amend the standstill and voting provisions in the investor agreement to be consistent with the terms provided to such third party.
	In accordance with the investor agreement, as a result of our issuance of shares in connection with our acquisition of Sirna Therapeutics, Inc., or Sirna, described below, in March 2014, Genzyme exercised its right to purchase an additional 344,448 shares of our common stock for $23.0 million, allowing Genzyme to maintain its ownership level of our common stock of approximately 12%.
	We determined that the deliverables for the programs Genzyme is currently collaborating with us on include the licenses to our patisiran and ALN-TTRsc clinical programs, which licenses were delivered to Genzyme upon the closing date of the transaction, and the associated development activities, joint steering committee participation and information exchange for these clinical programs. We also determined that, pursuant to the accounting guidance governing revenue recognition on multiple element arrangements, the license and associated undelivered development activities, joint steering committee participation and information exchange activities did not have standalone value due to the specialized nature of the services to be provided by us. In addition, while Genzyme has the ability to grant sublicenses, it cannot sublicense all or substantially all of its rights under the 2014 Genzyme collaboration. The uniqueness of our services and the limited sublicense rights are indicators that standalone value is not present in the arrangement. Therefore the deliverables are not separable and, accordingly, the license and undelivered services were treated as a single unit of account. When multiple deliverables are accounted for as a single unit of account, we base our revenue recognition model on the final deliverable. Under the 2014 Genzyme collaboration, the last deliverables for patisiran and ALN-TTRsc are expected to be completed within five years.
	We determined that the total cash received from Genzyme under the now superseded 2012 Genzyme agreement reflects consideration for certain of the performance obligations for ALN-TTR programs included in the 2014 Genzyme collaboration. Therefore we are recognizing the $33.5 million of deferred revenue under the 2012 Genzyme agreement on a straight-line basis over the period of performance of the ALN-TTR programs, which is currently five years. As future consideration, including any milestones or reimbursement for research and development services, is achieved, we will recognize as revenue a portion of these payments equal to the percentage of the performance period completed when the milestone or service has been satisfied, multiplied by the amount of the payment. We will recognize the remaining portion of consideration received over the remaining performance period on a straight-line basis.
	We determined that the opt-in rights that Genzyme has for future genetic medicine programs represent separate and additional deliverables that Genzyme may receive from us in future periods. Upon each opt-in by Genzyme, we have determined that each program and the related activities will represent a single unit of account and, consistent with our accounting policies, we will base our revenue recognition period on the final deliverable associated with each future opt-in, if any.
	Asset acquisition
	In-process research and development
	In January 2014, we entered into a stock purchase agreement with Sirna, Merck Sharp & Dohme Corp., or Merck, and, for limited purposes, Merck & Co., Inc., pursuant to which we purchased from Merck all of Merck’s right, title and interest in and to all of the outstanding shares of common stock of Sirna. The Merck transaction closed on March 5, 2014. Sirna possesses intellectual property and RNAi assets including early-stage pre-clinical therapeutic candidates, chemistry, and siRNA-conjugate and other delivery technologies that we intend to integrate into our platform for delivery of RNAi therapeutics.
	At the closing of the transaction, we paid Merck $25.0 million in cash and issued 2,142,037 shares of our common stock. We recorded this issuance using the price of our common stock on March 5, 2014, the date that these shares were issued to Merck. Based on the common stock price of $81.36, the fair value of the shares issued was $174.3 million. As a result of the cash payment and issuance of shares to Merck, we recorded a total of $199.3 million to in-process research and development expense. We issued an additional 378,007 shares of common stock to Merck on May 19, 2014 upon the completion of certain technology transfer activities during the second quarter of 2014. In the first quarter of 2014, we recorded a liability of $25.4 million associated with the then future obligation to issue these shares, based on the then current price of our common stock, which was also charged to in-process research and development expense. Upon completion of these technology transfer activities in the second quarter of 2014, we re-measured the expense recorded in connection with these shares using the then current price of our common stock, resulting in a credit of $3.9 million. We recorded a credit of $3.9 million and an expense of $220.8 million, respectively, to in-process research and development for the three and six months ended June 30, 2014 as a result of this asset acquisition. In future periods, there will be no additional charges recorded to in-process research and development related to the purchase of the Sirna RNAi assets from Merck.
	We accounted for this transaction as an acquisition of in-process research and development assets and recorded the entire amount to in-process research and development expense as we did not acquire any employees, manufacturing or other facilities, developed processes or clinical-stage assets as part of our acquisition of Sirna.
	Pursuant to the Sirna agreement, Merck is also eligible to receive the following consideration from us: (i) up to an aggregate of $10.0 million upon the achievement by us or our related parties of specified regulatory milestones for RNAi products covered by Sirna intellectual property, and (ii) up to an aggregate of $105.0 million upon the achievement by us or our related parties of specified development and regulatory ($40.0 million) and commercial ($65.0 million) milestones associated with the clinical development progress of certain pre-clinical candidates discovered by Sirna, together with low single-digit royalties for our products and single-digit royalties for Sirna products, in each case based on annual worldwide net sales, if any, by us and our related parties of any such products.
	Under the Sirna agreement, Merck also agreed not to dispose of (i) any shares of our common stock beneficially owned for a period of six months following the closing date, subject to certain limited exceptions, and (ii) 50% of the shares of our common stock beneficially owned for a period of six additional months following the termination of the initial lock-up, referred to as the Subsequent Lock-Up. During and following the expiration of the Subsequent Lock-Up, Merck will be permitted to sell such shares of our common stock subject to certain limitations, including certain volume and manner of sale restrictions.

COMMITMENTS_AND_CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	6 Months Ended
	Jun. 30, 2014
COMMITMENTS AND CONTINGENCIES	'
	3. COMMITMENTS AND CONTINGENCIES
	Operating Lease
	We lease office and laboratory space located at 300 Third Street, Cambridge, Massachusetts for our corporate headquarters under a non-cancelable real property lease agreement by and between us and ARE-MA Region No. 28, LLC, or the Landlord, dated as of September 26, 2003, as amended by a First Amendment to Lease dated March 16, 2006, a Second Amendment to Lease dated June 26, 2009, a Third Amendment to Lease dated May 11, 2010 and a Fourth Amendment to Lease dated November 4, 2011, referred to collectively as the Lease. Pursuant to the Lease, we lease a total of approximately 129,000 square feet of office and laboratory space. The term of the Lease was set to expire in September 2016.
	In March 2014, we and the Landlord entered into a Fifth Amendment to Lease, pursuant to which we exercised our option to extend the Lease for an additional five years, through September 30, 2021. Under the Fifth Amendment to Lease, we have the option to extend the Lease, as amended, for one additional five-year term. As a result of the Fifth Amendment to Lease, our operating lease obligations through 2021 increased by $37.8 million.
	Litigation
	University of Utah Litigation
	On March 22, 2011, The University of Utah, or Utah, filed a civil complaint in the United States District Court for the District of Massachusetts against us, Max Planck Gesellschaft Zur Foerderung Der Wissenschaften e.V. and Max Planck Innovation GmbH, together, Max Planck, the Whitehead Institute for Biomedical Research, or Whitehead, the Massachusetts Institute of Technology, or MIT, and the University of Massachusetts, or UMass, claiming a professor at Utah is the sole inventor or, in the alternative, a joint inventor, of the Tuschl patents. Utah is seeking changes to the inventorship of the Tuschl patents, unspecified damages and other relief. On October 31, 2011, we, Max Planck, Whitehead, MIT and UMass filed a motion to dismiss. Also on October 31, 2011, UMass filed a motion to dismiss on separate grounds, which we, Max Planck, Whitehead and MIT have joined. On December 31, 2011, Utah filed a second amended complaint dropping UMass as a defendant and adding as defendants several UMass officials. In June 2012, the Court denied both motions to dismiss. We, Max Planck, Whitehead, MIT and UMass filed an appeal of the Court’s ruling on the motion to dismiss for lack of jurisdiction and a motion requesting that the Court stay the case pending the outcome of the appeal. In July 2012, the Court stayed discovery in the case pending the outcome of the defendants’ appeal. In August 2013, the United States Court of Appeals for the Federal Circuit, or CAFC, affirmed the lower Court’s ruling, in a split decision. In September 2013, we filed a petition with the CAFC for rehearing or rehearing en banc. In November 2013, the CAFC denied our petition for rehearing or rehearing en banc and remanded the case back to the lower Court. In February 2014, we filed a petition for writ of certiorari from the Supreme Court and a motion to stay the lower Court proceedings pending a decision from the Supreme Court on our petition. The lower Court granted our motion to stay the proceedings, however, in June 2014 the Supreme Court denied our petition for certiorari and the case will proceed in the United States District Court for the District of Massachusetts.
	Although we believe we have meritorious defenses and intend to vigorously defend ourselves in this matter, litigation is subject to inherent uncertainty and a court could ultimately rule against us. In addition, the defense of litigation and related matters are costly and may divert the attention of our management and other resources that would otherwise be engaged in other activities. We have not recorded an estimate of the possible loss associated with this legal proceeding due to the uncertainties related to both the likelihood and the amount of any possible loss or range of loss.
	Our accounting policy for accrual of legal costs is to recognize such expenses as incurred.

SUMMARY_OF_SIGNIFICANT_ACCOUNT1

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	6 Months Ended
	Jun. 30, 2014
Basis of Presentation and Principles of Consolidation	'
	Basis of Presentation and Principles of Consolidation
	The accompanying condensed consolidated financial statements of Alnylam Pharmaceuticals, Inc. are unaudited and have been prepared in accordance with accounting principles generally accepted in the United States of America, or GAAP, applicable to interim periods and, in the opinion of management, include all normal and recurring adjustments that are necessary to state fairly the results of operations for the reported periods. Our condensed consolidated financial statements have also been prepared on a basis substantially consistent with, and should be read in conjunction with, our audited consolidated financial statements for the year ended December 31, 2013, which were included in our Annual Report on Form 10-K that was filed with the Securities and Exchange Commission, or SEC, on February 20, 2014. The year-end condensed consolidated balance sheet data was derived from our audited financial statements, but does not include all disclosures required by GAAP. The results of our operations for any interim period are not necessarily indicative of the results of our operations for any other interim period or for a full fiscal year.
	The accompanying condensed consolidated financial statements reflect the operations of Alnylam and our wholly-owned subsidiaries. All significant intercompany accounts and transactions have been eliminated.
Use of Estimates	'
	Use of Estimates
	The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.
Net Loss Per Common Share	'
	Net Loss Per Common Share
	We compute basic net loss per common share by dividing net loss by the weighted average number of common shares outstanding. We compute diluted net loss per common share by dividing net loss by the weighted average number of common shares and dilutive potential common share equivalents then outstanding. Potential common shares consist of shares issuable upon the exercise of stock options (using the treasury stock method) and unvested restricted stock awards. Because the inclusion of potential common shares would be anti-dilutive for all periods presented, diluted net loss per common share is the same as basic net loss per common share.
	The following table sets forth for each period presented the potential common shares (prior to consideration of the treasury stock method) excluded from the calculation of net loss per common share because their inclusion would be anti-dilutive, in thousands:
		At June 30,
		2014			2013
	Options to purchase common stock		8,038			8,567
	Unvested restricted common stock		23			604
			8,061			9,171
Public Offering	'
	Public Offering
	In January 2013, we sold an aggregate of 9,200,000 shares of our common stock through an underwritten public offering at a price to the public of $20.13 per share. As a result of this offering, we received aggregate net proceeds of $173.6 million, after deducting underwriting discounts and commissions and other offering expenses of $11.6 million.
Fair Value Measurements	'
	Fair Value Measurements
	The fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. The following tables present information about our assets that are measured at fair value on a recurring basis at June 30, 2014 and December 31, 2013, and indicate the fair value hierarchy of the valuation techniques we utilized to determine such fair value. In general, fair values determined by Level 1 inputs utilize quoted prices (unadjusted) in active markets for identical assets or liabilities. Fair values determined by Level 2 inputs utilize data points that are observable, such as quoted prices (adjusted), interest rates and yield curves. Fair values determined by Level 3 inputs utilize unobservable data points for the asset or liability, and include situations where there is little, if any, market activity for the asset or liability. The fair value hierarchy level is determined by the lowest level of significant input. Financial assets measured at fair value on a recurring basis are summarized as follows, in thousands:
	Description	At			Quoted Prices			Significant			Significant
		June 30,			in Active			Observable			Unobservable
		2014			Markets			Inputs			Inputs
					(Level 1)			(Level 2)			(Level 3)
	Cash equivalents	$	70,110		$	57,920		$	12,190		$	—
	Marketable securities (fixed income):
	Corporate notes		644,353			—			644,353			—
	U.S. government-sponsored enterprise securities		59,638			—			59,638			—
	Municipal debt securities		9,031			—			9,031			—
	Commercial paper		162,148			—			162,148			—
	Marketable securities (Regulus equity holdings)		49,450			49,450			—			—
	Total	$	994,730		$	107,370		$	887,360		$	—
	Description	At			Quoted Prices			Significant			Significant
		December 31,			in Active			Observable			Unobservable
		2013			Markets			Inputs			Inputs
					(Level 1)			(Level 2)			(Level 3)
	Cash equivalents	$	32,571		$	32,571		$	—		$	—
	Marketable securities (fixed income):
	Corporate notes		228,462			—			228,462			—
	U.S. government-sponsored enterprise securities		56,863			—			56,863			—
	Commercial paper		11,978			—			11,978			—
	Marketable securities (Regulus equity holdings)		45,452			45,452			—			—
	Total	$	375,326		$	78,023		$	297,303		$	—
	During the six months ended June 30, 2014, there were no transfers between Level 1 and Level 2 financial assets. The carrying amounts reflected in our condensed consolidated balance sheets for cash, billed and unbilled collaboration receivables, other current assets, accounts payable, and accrued expenses approximate fair value due to their short-term maturities.
Investments in Marketable Securities	'
	Investments in Marketable Securities
	We invest our excess cash balances in short-term and long-term marketable debt and equity securities. We classify our investments in marketable debt securities as either held-to-maturity or available-for-sale based on facts and circumstances present at the time we purchased the securities. At each balance sheet date presented, we classified all of our investments in debt and equity securities as available-for-sale. We report available-for-sale investments at fair value at each balance sheet date and include any unrealized holding gains and losses (the adjustment to fair value) in accumulated other comprehensive income (loss), a component of stockholders’ equity. At June 30, 2014, the balance in our accumulated other comprehensive income was composed solely of activity related to our available-for-sale marketable securities, including our investment in equity securities of Regulus Therapeutics Inc., or Regulus. Realized gains and losses are determined using the specific identification method and are included in other income. We did not recognize any realized gains or losses from sales of our available-for-sale securities during the six months ended June 30, 2014, and as a result, did not reclassify any amount out of accumulated other comprehensive income for the same period. If any adjustment to fair value reflects a decline in the value of the investment, we consider all available evidence to evaluate the extent to which the decline is “other than temporary” and, if so, mark the investment to market through a charge to our condensed consolidated statements of comprehensive income (loss). We did not record any impairment charges related to our fixed income marketable securities during the current period. Our marketable securities are classified as cash equivalents if the original maturity, from the date of purchase, is 90 days or less, and as marketable securities if the original maturity, from the date of purchase, is in excess of 90 days. Our cash equivalents are composed of money market funds and corporate notes.
	In the fourth quarter of 2012, we began accounting for our investment in Regulus as an available-for-sale marketable security. Intraperiod tax allocation rules require us to allocate our provision for income taxes between continuing operations and other categories of earnings, such as other comprehensive income. In periods in which we have a year-to-date pre-tax loss from continuing operations and pre-tax income in other categories of earnings, such as other comprehensive income, we must allocate the tax provision to the other categories of earnings. We then record a related tax benefit in continuing operations.
	The following tables summarize the fair value, accumulated other comprehensive income and intraperiod tax allocation regarding our investment in Regulus available-for-sale marketable securities at June 30, 2014 and 2013 and the activity for the three months ended June 30, 2014 and 2013, in thousands:
	Description	At			Three			Balance at
		March 31,			Months Ended			June 30, 2014
		2014			30-Jun-14
	Carrying value	$	12,449		$	—		$	12,449
	Accumulated other comprehensive income, before tax		43,029			(6,028	)		37,001
	Investment in equity securities of Regulus, as reported	$	55,478		$	(6,028	)	$	49,450
	Accumulated other comprehensive income, before tax	$	43,029		$	(6,028	)	$	37,001
	Intraperiod tax allocation recorded as a benefit from income taxes		(15,966	)		1,384			(14,582	)
	Intraperiod tax allocation recorded as an accrued liability		(1,380	)		1,088			(292	)
	Accumulated other comprehensive income, net of tax	$	25,683		$	(3,556	)	$	22,127
	Description	At			Three			Balance at
		March 31,			Months Ended			June 30, 2013
		2013			June 30, 2013
	Carrying value	$	12,449		$	—		$	12,449
	Accumulated other comprehensive income, before tax		35,217			12,670			47,887
	Investment in equity securities of Regulus, as reported	$	47,666		$	12,670		$	60,336
	Accumulated other comprehensive income, before tax	$	35,217		$	12,670		$	47,887
	Intraperiod tax allocation recorded as a benefit from income taxes		(11,134	)		(2,884	)		(14,018	)
	Intraperiod tax allocation recorded as an accrued liability		(3,023	)		(2,209	)		(5,232	)
	Accumulated other comprehensive income, net of tax	$	21,060		$	7,577		$	28,637
	The following tables summarize the fair value, accumulated other comprehensive income and intraperiod tax allocation regarding our investment in Regulus available-for-sale marketable securities at June 30, 2014 and 2013 and the activity for the six months ended June 30, 2014 and 2013, in thousands:
	Description	At			Six			Balance at
		December 31,			Months Ended			June 30, 2014
		2013			30-Jun-14
	Carrying value	$	12,449		$	—		$	12,449
	Accumulated other comprehensive income, before tax		33,003			3,998			37,001
	Investment in equity securities of Regulus, as reported	$	45,452		$	3,998		$	49,450
	Accumulated other comprehensive income, before tax	$	33,003		$	3,998		$	37,001
	Intraperiod tax allocation recorded as a benefit from income taxes		(13,267	)		(1,315	)		(14,582	)
	Intraperiod tax allocation recorded as an accrued liability		—			(292	)		(292	)
	Accumulated other comprehensive income, net of tax	$	19,736		$	2,391		$	22,127
	Description	At			Six			Balance at
		December 31,			Months Ended			June 30, 2013
		2012			30-Jun-13
	Carrying value	$	12,449		$	—		$	12,449
	Accumulated other comprehensive income, before tax		26,299			21,588			47,887
	Investment in equity securities of Regulus, as reported	$	38,748		$	21,588		$	60,336
	Accumulated other comprehensive income, before tax	$	26,299		$	21,588		$	47,887
	Intraperiod tax allocation recorded as a benefit from income taxes		(10,572	)		(3,446	)		(14,018	)
	Intraperiod tax allocation recorded as an accrued liability		—			(5,232	)		(5,232	)
	Accumulated other comprehensive income, net of tax	$	15,727		$	12,910		$	28,637
	We obtain fair value measurement data for our marketable securities from independent pricing services. We perform validation procedures to ensure the reasonableness of this data. This includes meeting with the independent pricing services to understand the methods and data sources used. Additionally, we perform our own review of prices received from the independent pricing services by comparing these prices to other sources and confirming those securities are trading in active markets.
	The following tables summarize our marketable securities, other than our holdings in Regulus noted above, at June 30, 2014 and December 31, 2013, in thousands:
		At June 30, 2014
	Description	Amortized			Gross			Gross			Fair Value
		Cost			Unrealized			Unrealized
					Gains			Losses
	Commercial paper (Due within 1 year)	$	162,170		$	4		$	(26	)	$	162,148
	Corporate notes (Due within 1 year)		347,396			101			(67	)		347,430
	Corporate notes (Due after 1 year through 2 years)		297,086			70			(233	)		296,923
	U.S. government-sponsored enterprise securities (Due within 1 year)		15,001			6			—			15,007
	U.S. government-sponsored enterprise securities (Due after 1 year through 2 years)		44,658			2			(29	)		44,631
	Municipal debt securities (Due after 1 year through 2 years)		9,003			28			—			9,031
	Total	$	875,314		$	211		$	(355	)	$	875,170
		At December 31, 2013
	Description	Amortized			Gross			Gross			Fair Value
		Cost			Unrealized			Unrealized
					Gains			Losses
	Commercial paper (Due within 1 year)	$	11,983		$	—		$	(5	)	$	11,978
Corporate notes (Due within 1 year)		154,175			33			(46	)		154,162
Corporate notes (Due after 1 year through 2 years)		74,312			23			(35	)		74,300
U.S. government-sponsored enterprise securities (Due within 1 year)		26,553			8			—			26,561
U.S. government-sponsored enterprise securities (Due after 1 year through 2 years)		30,300			2			—			30,302
Total	$	297,323		$	66		$	(86	)	$	297,303
Recent Accounting Pronouncements	'
	Recent Accounting Pronouncements
	In May 2014, the Financial Accounting Standards Board, or FASB, issued a new revenue recognition standard which amends revenue recognition principles and provides a single, comprehensive set of criteria for revenue recognition within and across all industries. The new standard provides a five step framework whereby revenue is recognized when promised goods or services are transferred to a customer at an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The standard also requires enhanced disclosures pertaining to revenue recognition in both interim and annual periods. For public companies, the standard is effective for interim and annual reporting periods beginning after December 15, 2016. Early adoption is not permitted. The standard allows for adoption using a full retrospective method or a modified retrospective method. We are currently evaluating the method of adoption and the expected impact that the standard could have on our condensed consolidated financial statements and related disclosures.

SUMMARY_OF_SIGNIFICANT_ACCOUNT2

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)	6 Months Ended
	Jun. 30, 2014
Potential Common Shares Excluded from the Calculation of Net Loss Per Common Share	'
	The following table sets forth for each period presented the potential common shares (prior to consideration of the treasury stock method) excluded from the calculation of net loss per common share because their inclusion would be anti-dilutive, in thousands:
		At June 30,
		2014			2013
	Options to purchase common stock		8,038			8,567
	Unvested restricted common stock		23			604
			8,061			9,171
Fair Value Measured on Recurring Basis	'
	Financial assets measured at fair value on a recurring basis are summarized as follows, in thousands:
	Description	At			Quoted Prices			Significant			Significant
		June 30,			in Active			Observable			Unobservable
		2014			Markets			Inputs			Inputs
					(Level 1)			(Level 2)			(Level 3)
	Cash equivalents	$	70,110		$	57,920		$	12,190		$	—
	Marketable securities (fixed income):
	Corporate notes		644,353			—			644,353			—
	U.S. government-sponsored enterprise securities		59,638			—			59,638			—
	Municipal debt securities		9,031			—			9,031			—
	Commercial paper		162,148			—			162,148			—
	Marketable securities (Regulus equity holdings)		49,450			49,450			—			—
	Total	$	994,730		$	107,370		$	887,360		$	—
	Description	At			Quoted Prices			Significant			Significant
		December 31,			in Active			Observable			Unobservable
		2013			Markets			Inputs			Inputs
					(Level 1)			(Level 2)			(Level 3)
	Cash equivalents	$	32,571		$	32,571		$	—		$	—
	Marketable securities (fixed income):
	Corporate notes		228,462			—			228,462			—
	U.S. government-sponsored enterprise securities		56,863			—			56,863			—
	Commercial paper		11,978			—			11,978			—
	Marketable securities (Regulus equity holdings)		45,452			45,452			—			—
	Total	$	375,326		$	78,023		$	297,303		$	—
Summary of Fair Value Accumulated Other Comprehensive Income and Intraperiod Tax Allocation in Regulus Available-for-Sale Marketable Securities	'
	The following tables summarize the fair value, accumulated other comprehensive income and intraperiod tax allocation regarding our investment in Regulus available-for-sale marketable securities at June 30, 2014 and 2013 and the activity for the three months ended June 30, 2014 and 2013, in thousands:
	Description	At			Three			Balance at
		March 31,			Months Ended			June 30, 2014
		2014			30-Jun-14
	Carrying value	$	12,449		$	—		$	12,449
	Accumulated other comprehensive income, before tax		43,029			(6,028	)		37,001
	Investment in equity securities of Regulus, as reported	$	55,478		$	(6,028	)	$	49,450
	Accumulated other comprehensive income, before tax	$	43,029		$	(6,028	)	$	37,001
	Intraperiod tax allocation recorded as a benefit from income taxes		(15,966	)		1,384			(14,582	)
	Intraperiod tax allocation recorded as an accrued liability		(1,380	)		1,088			(292	)
	Accumulated other comprehensive income, net of tax	$	25,683		$	(3,556	)	$	22,127
	Description	At			Three			Balance at
		March 31,			Months Ended			June 30, 2013
		2013			June 30, 2013
	Carrying value	$	12,449		$	—		$	12,449
	Accumulated other comprehensive income, before tax		35,217			12,670			47,887
	Investment in equity securities of Regulus, as reported	$	47,666		$	12,670		$	60,336
	Accumulated other comprehensive income, before tax	$	35,217		$	12,670		$	47,887
	Intraperiod tax allocation recorded as a benefit from income taxes		(11,134	)		(2,884	)		(14,018	)
	Intraperiod tax allocation recorded as an accrued liability		(3,023	)		(2,209	)		(5,232	)
	Accumulated other comprehensive income, net of tax	$	21,060		$	7,577		$	28,637
	The following tables summarize the fair value, accumulated other comprehensive income and intraperiod tax allocation regarding our investment in Regulus available-for-sale marketable securities at June 30, 2014 and 2013 and the activity for the six months ended June 30, 2014 and 2013, in thousands:
	Description	At			Six			Balance at
		December 31,			Months Ended			June 30, 2014
		2013			30-Jun-14
	Carrying value	$	12,449		$	—		$	12,449
	Accumulated other comprehensive income, before tax		33,003			3,998			37,001
	Investment in equity securities of Regulus, as reported	$	45,452		$	3,998		$	49,450
	Accumulated other comprehensive income, before tax	$	33,003		$	3,998		$	37,001
	Intraperiod tax allocation recorded as a benefit from income taxes		(13,267	)		(1,315	)		(14,582	)
	Intraperiod tax allocation recorded as an accrued liability		—			(292	)		(292	)
	Accumulated other comprehensive income, net of tax	$	19,736		$	2,391		$	22,127
	Description	At			Six			Balance at
		December 31,			Months Ended			June 30, 2013
		2012			30-Jun-13
	Carrying value	$	12,449		$	—		$	12,449
	Accumulated other comprehensive income, before tax		26,299			21,588			47,887
	Investment in equity securities of Regulus, as reported	$	38,748		$	21,588		$	60,336
	Accumulated other comprehensive income, before tax	$	26,299		$	21,588		$	47,887
	Intraperiod tax allocation recorded as a benefit from income taxes		(10,572	)		(3,446	)		(14,018	)
	Intraperiod tax allocation recorded as an accrued liability		—			(5,232	)		(5,232	)
	Accumulated other comprehensive income, net of tax	$	15,727		$	12,910		$	28,637
Summary of Company's Marketable Securities Excluding Regulus	'
	The following tables summarize our marketable securities, other than our holdings in Regulus noted above, at June 30, 2014 and December 31, 2013, in thousands:
		At June 30, 2014
	Description	Amortized			Gross			Gross			Fair Value
		Cost			Unrealized			Unrealized
					Gains			Losses
	Commercial paper (Due within 1 year)	$	162,170		$	4		$	(26	)	$	162,148
	Corporate notes (Due within 1 year)		347,396			101			(67	)		347,430
	Corporate notes (Due after 1 year through 2 years)		297,086			70			(233	)		296,923
	U.S. government-sponsored enterprise securities (Due within 1 year)		15,001			6			—			15,007
	U.S. government-sponsored enterprise securities (Due after 1 year through 2 years)		44,658			2			(29	)		44,631
	Municipal debt securities (Due after 1 year through 2 years)		9,003			28			—			9,031
	Total	$	875,314		$	211		$	(355	)	$	875,170
		At December 31, 2013
	Description	Amortized			Gross			Gross			Fair Value
		Cost			Unrealized			Unrealized
					Gains			Losses
	Commercial paper (Due within 1 year)	$	11,983		$	—		$	(5	)	$	11,978
	Corporate notes (Due within 1 year)		154,175			33			(46	)		154,162
	Corporate notes (Due after 1 year through 2 years)		74,312			23			(35	)		74,300
	U.S. government-sponsored enterprise securities (Due within 1 year)		26,553			8			—			26,561
	U.S. government-sponsored enterprise securities (Due after 1 year through 2 years)		30,300			2			—			30,302
	Total	$	297,323		$	66		$	(86	)	$	297,303

SIGNIFICANT_AGREEMENTS_Tables

SIGNIFICANT AGREEMENTS (Tables)	6 Months Ended
	Jun. 30, 2014
Revenue from Collaborators	'
	The following table summarizes our total consolidated net revenues from collaborators, for the periods indicated, in thousands:
		Three Months Ended June 30,				Six Months Ended June 30,
		2014		2013		2014		2013
	Takeda	$	5,494	$	5,494	$	10,987	$	10,987
	Monsanto		1,410		1,410		2,820		2,820
	Cubist		—		—		—		9,721
	Other		391		1,783		1,763		3,801
	Total net revenues from collaborators	$	7,295	$	8,687	$	15,570	$	27,329

Potential_Common_Shares_Common

Potential Common Shares Common Shares Excluded from Calculation of Net Loss Per Common Share (Detail)	6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'
Anti-dilutive securities excluded from computation of earnings	8,061	9,171
Options to Purchase Common Stock	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'
Anti-dilutive securities excluded from computation of earnings	8,038	8,567
Unvested Restricted Common Stock	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'
Anti-dilutive securities excluded from computation of earnings	23	604

Recovered_Sheet1

Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)	1 Months Ended	6 Months Ended
	Jan. 31, 2013	Jun. 30, 2014	Jun. 30, 2013
Significant Accounting Policies [Line Items]	'	'	'
Common stocks issued through underwritten public offering	9,200,000	'	'
Underwritten public offering amount per share	$20.13	'	'
Net proceeds from public issue, after deducting expenses	$173,600,000	'	$173,572,000
Underwriting discounts and commissions and other estimated offering expenses	$11,600,000	'	'
Marketable securities classified as cash equivalents, original maturity	'	'90 days	'
Policy for marketable securities	'	'90 days	'

Fair_Value_Measured_on_Recurri

Fair Value Measured on Recurring Basis (Detail) (Recurring, 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]	'	'
Cash equivalents	$70,110	$32,571
Total	994,730	375,326
Corporate notes	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities, Fair value disclosure	644,353	228,462
U.S. Government obligations	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities, Fair value disclosure	59,638	56,863
Municipal Debt Securities	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities, Fair value disclosure	9,031	'
Commercial paper	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities, Fair value disclosure	162,148	11,978
Equity Securities	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities, Fair value disclosure	49,450	45,452
Quoted Prices in Active Markets (Level 1)	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Cash equivalents	57,920	32,571
Total	107,370	78,023
Quoted Prices in Active Markets (Level 1) | Equity Securities	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities, Fair value disclosure	49,450	45,452
Significant Observable Inputs (Level 2)	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Cash equivalents	12,190	'
Total	887,360	297,303
Significant Observable Inputs (Level 2) | Corporate notes	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities, Fair value disclosure	644,353	228,462
Significant Observable Inputs (Level 2) | U.S. Government obligations	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities, Fair value disclosure	59,638	56,863
Significant Observable Inputs (Level 2) | Municipal Debt Securities	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities, Fair value disclosure	9,031	'
Significant Observable Inputs (Level 2) | Commercial paper	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities, Fair value disclosure	$162,148	$11,978

Summary_of_Fair_Value_Accumula

Summary of Fair Value Accumulated Other Comprehensive Income and Intraperiod Tax Allocation in Available-for-Sale Marketable Securities (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	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2013	Dec. 31, 2012
Schedule of Available-for-sale Securities [Line Items]	'	'	'	'	'	'	'	'
Intraperiod tax allocation recorded as an accrued liability	($4,081)	'	($4,081)	'	'	'	'	'
Accumulated other comprehensive income, net of tax	-3,047	7,309	2,266	12,468	'	'	'	'
Regulus Therapeutics Inc	'	'	'	'	'	'	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'	'	'	'	'	'	'
Carrying value	12,449	12,449	12,449	12,449	12,449	12,449	12,449	12,449
Accumulated other comprehensive income, before tax	37,001	47,887	37,001	47,887	43,029	33,003	35,217	26,299
Investment in equity securities of Regulus, as reported	49,450	60,336	49,450	60,336	55,478	45,452	47,666	38,748
Accumulated other comprehensive income, before tax	37,001	47,887	37,001	47,887	43,029	33,003	35,217	26,299
Intraperiod tax allocation recorded as a benefit from income taxes	-14,582	-14,018	-14,582	-14,018	-15,966	-13,267	-11,134	-10,572
Intraperiod tax allocation recorded as an accrued liability	-292	-5,232	-292	-5,232	-1,380	'	-3,023	'
Accumulated other comprehensive income, net of tax	22,127	28,637	22,127	28,637	25,683	19,736	21,060	15,727
Accumulated other comprehensive income, before tax	-6,028	12,670	3,998	21,588	'	'	'	'
Investment in equity securities of Regulus, as reported	-6,028	12,670	3,998	21,588	'	'	'	'
Accumulated other comprehensive income, before tax	-6,028	12,670	3,998	21,588	'	'	'	'
Intraperiod tax allocation recorded as a benefit from income taxes	1,384	-2,884	-1,315	-3,446	'	'	'	'
Intraperiod tax allocation recorded as an accrued liability	1,088	-2,209	-292	-5,232	'	'	'	'
Accumulated other comprehensive income, net of tax	($3,556)	$7,577	$2,391	$12,910	'	'	'	'

Summary_of_Companys_Marketable

Summary of Company's Marketable Securities (Detail) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Schedule of Available-for-sale Securities [Line Items]	'	'
Amortized Cost	$875,314	$297,323
Gross Unrealized Gains	211	66
Gross Unrealized Losses	-355	-86
Fair Value	875,170	297,303
Commercial paper (Due within 1 year)	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Amortized Cost	162,170	11,983
Gross Unrealized Gains	4	'
Gross Unrealized Losses	-26	-5
Fair Value	162,148	11,978
Corporate notes (Due within 1 year)	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Amortized Cost	347,396	154,175
Gross Unrealized Gains	101	33
Gross Unrealized Losses	-67	-46
Fair Value	347,430	154,162
Corporate notes (Due after 1 year through 2 years)	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Amortized Cost	297,086	74,312
Gross Unrealized Gains	70	23
Gross Unrealized Losses	-233	-35
Fair Value	296,923	74,300
U.S. Government obligations (Due within 1 year)	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Amortized Cost	15,001	26,553
Gross Unrealized Gains	6	8
Fair Value	15,007	26,561
U.S. Government obligations (Due after 1 year through 2 years)	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Amortized Cost	44,658	30,300
Gross Unrealized Gains	2	2
Gross Unrealized Losses	-29	'
Fair Value	44,631	30,302
Municipal Debt Securities ((Due after 1 year through 2 years)	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Amortized Cost	9,003	'
Gross Unrealized Gains	28	'
Fair Value	$9,031	'

Revenue_from_Collaborators_Det

Revenue from Collaborators (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
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]	'	'	'	'
Total net revenues from collaborators	$7,295	$8,687	$15,570	$27,329
Takeda	'	'	'	'
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]	'	'	'	'
Total net revenues from collaborators	5,494	5,494	10,987	10,987
Monsanto	'	'	'	'
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]	'	'	'	'
Total net revenues from collaborators	1,410	1,410	2,820	2,820
Cubist	'	'	'	'
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]	'	'	'	'
Total net revenues from collaborators	'	'	'	9,721
Other	'	'	'	'
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]	'	'	'	'
Total net revenues from collaborators	$391	$1,783	$1,763	$3,801

Significant_Agreements_Additio

Significant Agreements - Additional Information (Detail) (USD $)

0 Months Ended

1 Months Ended

3 Months Ended

6 Months Ended

0 Months Ended

1 Months Ended

3 Months Ended

1 Months Ended

0 Months Ended

0 Months Ended

6 Months Ended

3 Months Ended

0 Months Ended

0 Months Ended

0 Months Ended

0 Months Ended

1 Months Ended

Mar. 05, 2014

Jan. 31, 2013

Jun. 30, 2014

Jun. 30, 2013

Jun. 30, 2014

Jun. 30, 2013

Mar. 05, 2014

Jan. 31, 2014

Jun. 30, 2014

Mar. 31, 2014

Mar. 05, 2014

Jan. 31, 2014

Jan. 31, 2014

Jan. 31, 2014

Jan. 31, 2014

Jan. 11, 2014

Feb. 27, 2014

Jan. 11, 2014

Jan. 11, 2014

Jan. 11, 2014

Jan. 11, 2014

Jun. 30, 2014

Dec. 31, 2013

Oct. 31, 2012

Dec. 31, 2013

Dec. 31, 2013

Jan. 11, 2014

Jan. 11, 2014

Jan. 14, 2014

Jan. 14, 2014

Jan. 14, 2014

Jan. 11, 2014

Jan. 11, 2014

Jan. 11, 2014

Mar. 31, 2014

Sirna Therapeutics

Sirna Therapeutics

Sirna Therapeutics

Sirna Therapeutics

Sirna Therapeutics

Sirna Therapeutics

Sirna Therapeutics

Clinical Development and Regulatory Milestone

Commercial Milestones

Genzyme

Genzyme

Genzyme

Genzyme

Genzyme

Genzyme

Genzyme

Genzyme

Genzyme

Genzyme

Genzyme

Genzyme

Genzyme

Genzyme

Genzyme

Genzyme

Genzyme

Genzyme

Genzyme

Genzyme

Intellectual Property

Additional

Sirna Therapeutics

Sirna Therapeutics

Minimum

Minimum

Maximum

Product Alliances

Product Alliances

Product Alliances

Product Alliances

Product Alliances

Global Collaboration Product

Global Collaboration Product

Regional Collaboration Product

Regional Collaboration Product

Regional Collaboration Product

Co-developed/ Co-promoted Collaboration Product

Co-developed/ Co-promoted Collaboration Product

Co-developed/ Co-promoted Collaboration Product

Phase Two Clinical Trial Patisiran

Phase Three Clinical Trial Patisiran

Upon Completion

Phase Three Clinical Trial ALN-TTRsc

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

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Upfront fee received

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$22,500,000

'

'

'

'

'

'

'

'

'

'

'

Amount earned upon achievement of milestone

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

7,000,000

4,000,000

'

'

'

'

'

'

'

'

'

Deferred revenue

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

33,500,000

'

'

'

'

'

'

'

'

'

'

'

'

Percentage of sharing in development cost

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

100.00%

'

20.00%

'

'

50.00%

'

'

'

Potential future payment for the achievement of certain development milestones

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

60,000,000

'

55,000,000

'

50,000,000

'

'

'

'

Maximum number of potential future milestones

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

200,000,000

'

75,000,000

'

'

75,000,000

'

'

'

Potential future payment for the achievement of specified commercialization milestones

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

140,000,000

'

20,000,000

'

'

'

'

'

'

Royalty rate

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

20.00%

'

20.00%

'

'

20.00%

'

'

Next potential milestone payment

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

25,000,000

'

Number of shares under agreement to sell stock

'

9,200,000

'

'

'

'

'

'

'

'

'

'

'

'

'

8,766,338

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

344,448

Aggregate cash consideration

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

700,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

23,000,000

Common stock price

'

$20.13

'

'

'

'

'

'

'

'

$81.36

'

'

'

'

'

$85.72

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Shares issued from purchases

'

'

'

'

'

'

174,300,000

'

'

'

'

'

'

'

'

751,500,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Excess of fair value over cash received for stock issuance

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

51,500,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Performance period

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'5 years

'

'

'

'

'

'5 years

'

'

'

'

'

'

'

'

'

'

'

'

'

Benefit from income taxes

'

'

-315,000

-2,884,000

-18,185,000

-3,446,000

'

'

'

'

'

'

'

'

'

-15,200,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Agreement to acquire outstanding shares of common stock percentage

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

5.00%

30.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Voting percentage

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

20.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Minimum percentage of ownership interest terminate

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

7.50%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Percentage of ownership interest

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

30.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Approximate percentage of ownership interest

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

12.00%

Asset acquisition cash consideration

'

'

'

'

25,000,000

'

25,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Asset acquisition issuable common stock, shares

'

'

'

'

'

'

2,142,037

'

378,007

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Liability for stock issuance

'

'

'

'

'

'

'

'

'

25,400,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

In-process research and development (credit) expense

199,300,000

'

-3,890,000

'

220,766,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Asset acquisition consideration upon achievement of milestones

'

'

'

'

'

'

'

$105,000,000

'

'

'

$10,000,000

'

$40,000,000

$65,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Lock up period

'

'

'

'

'

'

'

'6 months

'

'

'

'

'6 months

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Subsequent lock up period stock holding percentage

'

'

'

'

'

'

'

50.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Commitments_and_Contingencies_

Commitments and Contingencies - Additional Information (Detail) (USD $)	1 Months Ended	6 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Jun. 30, 2014
		sqft
Commitments and Contingencies [Line Items]	'	'
Area of office and laboratory space held under operating lease	'	129,000
Lease expiration date	'	'2016-09
Lease extension period	'5 years	'
Lease extended expiration date	30-Sep-21	'
First Amendment	'	'
Commitments and Contingencies [Line Items]	'	'
Lease amendment date	'	16-Mar-06
Second Amendment	'	'
Commitments and Contingencies [Line Items]	'	'
Lease amendment date	'	26-Jun-09
Third Amendment	'	'
Commitments and Contingencies [Line Items]	'	'
Lease amendment date	'	11-May-10
Fourth Amendment	'	'
Commitments and Contingencies [Line Items]	'	'
Lease amendment date	'	4-Nov-11
Fifth Amendment	'	'
Commitments and Contingencies [Line Items]	'	'
Operating lease obligation through 2021	37.8	'
Fifth Amendment | Optional	'	'
Commitments and Contingencies [Line Items]	'	'
Lease extension period	'5 years	'