4. License and Collaboration Agreements

Sanofi

On September 30, 2009, the Company entered into a license and collaboration agreement with Sanofi for the development and commercialization of a drug candidate being developed by the Company under the name MM-121. The agreement became effective on November 10, 2009 and Sanofi paid the Company a nonrefundable, noncreditable upfront license fee of $60.0 million. During the years ended 2010 and 2011, the Company received a total of $20.0 million in milestone payments associated with dosing the first patients in Phase 2 clinical trials in breast cancer and non-small cell lung cancer. During the first quarter of 2012, the Company received an additional milestone payment of $5.0 million associated with dosing the first patient in a Phase 2 clinical trial in ovarian cancer. The Company is eligible to receive additional future development, regulatory and sales milestone payments as well as future royalty payments depending on the success of MM-121.

Under the agreement, Sanofi is responsible for all MM-121 development and manufacturing costs. The Company has the right, but not the obligation, to co-promote MM-121 in the United States and to participate in the development of MM-121 through Phase 2 proof of concept trials. Sanofi reimburses the Company for direct costs incurred in development and compensates the Company for its internal development efforts based on a full time equivalent (“FTE”) rate. Also as part of the agreement, the Company was required to manufacture certain quantities of MM-121 and, at Sanofi’s and the Company’s option, may continue to manufacture additional quantities of MM-121 in the future. Sanofi reimburses the Company for direct costs incurred in manufacturing and compensates the Company for its internal manufacturing efforts based on an FTE rate. The Company satisfied its manufacturing obligations during 2010 and has elected to continue to manufacture quantities of MM-121.

The Company applied revenue recognition guidance to determine whether the performance obligations under this collaboration, including the license, the right to future technology, back-up compounds, participation on steering committees, development services and manufacturing services, could be accounted for separately or as a single unit of accounting. The Company determined that its development services performance obligation is considered a separate unit of accounting, as it is set at the Company’s option, has stand-alone value and the FTE rate is considered fair value. Therefore, the Company recognizes cost reimbursements for MM-121 development services as incurred. The Company determined that the license, the right to future technology, back-up compounds, participation on steering committees and manufacturing services performance obligations represented a single unit of accounting. As the Company cannot reasonably estimate its level of effort over the collaboration, the Company recognizes revenue from the upfront payment, milestone payment and manufacturing services payments using the contingency-adjusted performance model over the expected development period, which is currently estimated to be 12 years from the effective date of the agreement. Under this model, when a milestone is earned or manufacturing services are rendered and product is delivered, revenue is immediately recognized on a pro-rata basis in the period the milestone was achieved or product was delivered based on the time elapsed from the effective date of the agreement. Thereafter, the remaining portion is recognized on a straight-line basis over the remaining development period.

During the three months ended March 31, 2012 and 2013, the Company recognized revenue based on the following components of the Sanofi agreement:

	Three months ended March 31,
(in thousands)	2012		2013
Upfront payment	$	1,250	$	1,250
Milestone payments	1,412		521
Development services	8,142		11,590
Manufacturing services and other	521		741
Total	$	11,325	$	14,102

As of December 31, 2012 and March 31, 2013, the Company maintained the following assets and liabilities related to the Sanofi agreement:

(in thousands)	December 31, 2012		March 31, 2013

Accounts receivable, billed	$	1,577	$	5,217
Accounts receivable, unbilled	7,690		4,579
Deferred revenue	79,913		77,399

GTC Biotherapeutics, Inc.

In July 2009, the Company entered into a license agreement with GTC Biotherapeutics, Inc. (“GTC”) for the development of MM-093 by GTC. On March 19, 2013, GTC terminated the license agreement. As a result, the Company recognized the remaining $0.6 million of deferred revenue related to this license agreement during the first quarter of 2013.

PharmaEngine, Inc.

On May 5, 2011, the Company entered into an assignment, sublicense and collaboration agreement with PharmaEngine, Inc. (“PharmaEngine”) under which the Company reacquired rights in Europe and certain countries in Asia to a drug being developed under the name MM-398. In exchange, the Company agreed to pay PharmaEngine a nonrefundable, noncreditable upfront payment of $10.0 million and will be required to make up to an aggregate of $80.0 million in development and regulatory milestone payments and $130.0 million in sales milestone payments upon the achievement of specified development, regulatory and annual net sales milestones. During the first quarter of 2012, the Company paid a milestone of $5.0 million under the collaboration agreement with PharmaEngine in connection with dosing the first patient in a Phase 3 clinical trial of MM-398 in pancreatic cancer. PharmaEngine is also entitled to tiered royalties on net sales of MM-398 in Europe and certain countries in Asia. The Company is responsible for all future development costs of MM-398 except those required specifically for regulatory approval in Taiwan.

During the three months ended March 31, 2012 and 2013, the Company recognized research and development expenses of $5.3 million and $0.3 million, respectively, related to the agreement with PharmaEngine. These amounts included a $5.0 million milestone payment expensed during the first quarter of 2012.