Research and License Agreements	6 Months Ended
Jun. 30, 2014
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Research and License Agreements	9. Research and License Agreements In October 2011, the Company and Pfizer entered into a licensing agreement (the Pfizer Agreement) that provides Pfizer an exclusive worldwide license to rivipansel for vaso-occlusive crisis associated with sickle cell disease and for other diseases for which the drug candidate may be developed. The Company was responsible for completion of the Phase 2 trial, after which Pfizer will assume all further development and commercialization responsibilities. Upon execution of the Pfizer Agreement, the Company received an up-front payment of $22.5 million. The Pfizer Agreement also provides for potential milestone payments of up to $115.0 million upon the achievement of specified development milestones, including the dosing of the first patients in Phase 3 clinical trials for up to two indications and the first commercial sale of a licensed product in the United States and selected European countries for up to two indications; potential milestone payments of up to $70.0 million upon the achievement of specified regulatory milestones, including the acceptance of our filings for regulatory approval by regulatory authorities in the United States and Europe for up to two indications; and potential milestone payments of up to $135.0 million upon the achievement of specified levels of annual net sales of licensed products. In May 2014, the Company received a non-refundable payment of $15.0 million from Pfizer as a partial milestone payment owed to the Company upon the dosing of the first patient in the Phase 3 clinical trial. Upon the dosing of the first patient in a Phase 3 clinical trial of rivipansel, the Company will be entitled to receive the remaining $20.0 million of the scheduled milestone payment under the Pfizer Agreement. The Company has determined that each potential future clinical, development and regulatory milestone is substantive. Although sales-based milestones are not considered substantive, they are still recognized upon achievement of the milestone (assuming all other revenue recognition criteria have been met) because there are no undelivered elements that would preclude revenue recognition at that time. The Company is also eligible to receive royalties on future sales contingent upon annual net sales thresholds. In addition, the Company and Pfizer have formed a joint steering committee that will oversee and coordinate activities as set forth in the research program. The $22.5 million up-front payment was recognized over a period of 1.5 years through the six months ended March 31, 2013. During the six months ended June 30, 2013, the Company recorded revenue of $3.8 million pursuant to the Pfizer Agreement in the Company’s statement of operations. In May 2014, the Company received a non-refundable payment from Pfizer in the amount of $15.0 million. Pfizer has the right to terminate the Agreement by giving prior written notice. As of June 30, 2014, Pfizer and the Company are both in compliance with the provisions of the Agreement. In February 2004, the Company entered into a research services agreement (the Research Agreement) with the University of Basel (the University) for biological evaluation of selectin antagonists. Certain patents covering the rivipansel compound are subject to provisions of the Research Agreement. Under the terms of the Research Agreement, the Company is required to pay the University 10% payment of all milestone and royalty payments received from Pfizer with respect to rivipansel. During the three months ended June 30, 2014, the Company recorded an accrued expense of $1.5 million due to the University, representing 10% of the $15.0 million non-refundable cash milestone payment that the Company received from Pfizer in May 2014.

9. Research and License Agreements

In October 2011, the Company and Pfizer entered into a licensing agreement (the Pfizer Agreement) that provides Pfizer an exclusive worldwide license to rivipansel for vaso-occlusive crisis associated with sickle cell disease and for other diseases for which the drug candidate may be developed. The Company was responsible for completion of the Phase 2 trial, after which Pfizer will assume all further development and commercialization responsibilities. Upon execution of the Pfizer Agreement, the Company received an up-front payment of $22.5 million. The Pfizer Agreement also provides for potential milestone payments of up to $115.0 million upon the achievement of specified development milestones, including the dosing of the first patients in Phase 3 clinical trials for up to two indications and the first commercial sale of a licensed product in the United States and selected European countries for up to two indications; potential milestone payments of up to $70.0 million upon the achievement of specified regulatory milestones, including the acceptance of our filings for regulatory approval by regulatory authorities in the United States and Europe for up to two indications; and potential milestone payments of up to $135.0 million upon the achievement of specified levels of annual net sales of licensed products. In May 2014, the Company received a non-refundable payment of $15.0 million from Pfizer as a partial milestone payment owed to the Company upon the dosing of the first patient in the Phase 3 clinical trial. Upon the dosing of the first patient in a Phase 3 clinical trial of rivipansel, the Company will be entitled to receive the remaining $20.0 million of the scheduled milestone payment under the Pfizer Agreement.

The Company has determined that each potential future clinical, development and regulatory milestone is substantive. Although sales-based milestones are not considered substantive, they are still recognized upon achievement of the milestone (assuming all other revenue recognition criteria have been met) because there are no undelivered elements that would preclude revenue recognition at that time. The Company is also eligible to receive royalties on future sales contingent upon annual net sales thresholds. In addition, the Company and Pfizer have formed a joint steering committee that will oversee and coordinate activities as set forth in the research program. The $22.5 million up-front payment was recognized over a period of 1.5 years through the six months ended March 31, 2013. During the six months ended June 30, 2013, the Company recorded revenue of $3.8 million pursuant to the Pfizer Agreement in the Company’s statement of operations. In May 2014, the Company received a non-refundable payment from Pfizer in the amount of $15.0 million.

Pfizer has the right to terminate the Agreement by giving prior written notice. As of June 30, 2014, Pfizer and the Company are both in compliance with the provisions of the Agreement.

In February 2004, the Company entered into a research services agreement (the Research Agreement) with the University of Basel (the University) for biological evaluation of selectin antagonists. Certain patents covering the rivipansel compound are subject to provisions of the Research Agreement.

Under the terms of the Research Agreement, the Company is required to pay the University 10% payment of all milestone and royalty payments received from Pfizer with respect to rivipansel. During the three months ended June 30, 2014, the Company recorded an accrued expense of $1.5 million due to the University, representing 10% of the $15.0 million non-refundable cash milestone payment that the Company received from Pfizer in May 2014.