Summary of INFINITY PHARMACEUTICALS, INC.

Item 1.01 Entry into a Material Definitive Agreement

Strategic Alliance Agreements

On November 19, 2008, Infinity Pharmaceuticals, Inc. ("Infinity") entered into strategic alliance agreements (the "Strategic Alliance Agreements") with each of Mundipharma International Corporation Limited ("Mundipharma") and Purdue Pharmaceutical Products L.P. ("Purdue" and, together with Mundipharma, the "Purdue Companies") to develop and commercialize pharmaceutical products. The alliance includes product candidates that inhibit or target the Hedgehog cell signaling pathway and fatty acid amide hydrolase ("FAAH"), and product candidates arising out of all Infinity discovery projects in all disease fields that achieve development candidate status on or before December 31, 2011 (with Mundipharma having the right, through the exercise of two consecutive one-year options, to extend such period through December 31, 2013) (the "Funded Research Period"). The Strategic Alliance Agreements expressly exclude Infinity's heat shock protein 90 and Bcl-2 programs. During the Funded Research Period, Mundipharma also has an option to obtain commercialization rights outside of the United States for certain products and product candidates in-licensed by Infinity from third parties. The agreement with Purdue is focused on the development and commercialization of products targeting FAAH for sale in the United States. The agreement with Mundipharma is focused on the development and commercialization of all other products and product candidates for sale outside of the United States.

Under the Strategic Alliance Agreements, Infinity will have responsibility for the performance of early discovery projects and the development of all product candidates on a worldwide basis. The Purdue Companies will pay for, in the aggregate, 100% of all research and development expenses incurred by Infinity for all early discovery projects and for each product candidate until the later of December 31, 2013 and the commencement of the first phase 3 clinical study of such product candidate (the "Transition Date"). The parties have agreed upon a three year budget for research and development expenses of $50 million, $65 million and $85 million for the period beginning on November 19, 2008 and ending on December 31, 2009, calendar year 2010 and calendar year 2011, respectively. After the Transition Date for each product candidate, the Purdue Companies and Infinity will share all research and development costs for such product candidate equally.

Upon completion of the first phase 1 clinical study of the first product developed under the research program that inhibits or targets FAAH, Purdue and Mundipharma may elect to assume responsibility for the future development and commercialization of FAAH products for sale in and outside of the United States, respectively. The Purdue Companies have the right to opt out of any early discovery project or any preclinical or clinical development program on an annual basis in November of each year. The Purdue Companies also have a one-time right in mid-2009 to opt out of either or both of the Hedgehog development program or the FAAH project. In the event of an opt-out decision, the Purdue Companies will continue to provide funding for, in the aggregate, 100% of Infinity's budgeted research and development expenses for the applicable project or program for one year after the date of such opt-out. In addition, each party has the right to opt out of continued development of a product candidate after it has reached the Transition Date, with a one year tail funding obligation for its 50% of post-Transition Date research and development expenses. If a party exercises its right to opt-out of the development of a product or product candidate after the Transition Date, the other party may elect to continue the development and assume responsibility for the worldwide commercialization of such product or product candidate, subject to the payment of a royalty.

Except as set forth above with respect to FAAH products and opt-out products, Infinity will have the right and responsibility to market and sell products arising from the research program in the United States and Mundipharma will have the right and responsibility to market and sell products arising from the research program outside of the United States. Other than pursuant to the Strategic Alliance Agreements, neither Infinity nor Mundipharma may develop, manufacture or commercialize products that arise out of the research program or products that are directed to the same target or pathway as a product included in the research program, unless and until a party terminates its rights with respect to such products.

If Infinity in-licenses any product or product candidate for which commercialization rights outside of the United States are available for grant by Infinity to Mundipharma, Mundipharma will have the option to include such in-licensed product or product candidate in the alliance by paying Infinity a prescribed percentage of the up-front license fee or other acquisition cost, which percentage could be up to 60% of such fee or cost, in order for Mundipharma to obtain rights in all countries outside of the United States, and by funding research and development costs in the same manner as products or product candidates arising out of Infinity's internal discovery programs. The agreement with Mundipharma provides for the agreed-upon research and development budgets to be updated to reflect the inclusion of any in-licensed products or . . .