On December 16, 2021, Epizyme, Inc. received written notice from Glaxo Group Limited that GSK has elected to terminate the Collaboration and License Agreement dated January 8, 2011, as amended. GSK terminated the Agreement without cause, and in accordance with the terms of the Agreement and the notice of termination, the termination will be effective on March 16, 2022. The Agreement provided that the parties would discover, develop and commercialize novel small molecule histone methyltransferase, or HMT, inhibitors directed to available targets from the Company’s product platform. Under the terms of the Agreement, the Company granted GSK exclusive, worldwide license rights to HMT inhibitors directed to three targets. As part of the collaboration, the Company agreed to provide research and development services related to the licensed targets pursuant to agreed-upon research plans during a research term that ended January 8, 2015. The Company substantially completed all research obligations under the Agreement by the end of the first quarter of 2015 and completed the transfer of the remaining data and material for these programs to GSK in the second quarter of 2015. GSK was then responsible for all future development and commercialization. Subsequent to a GSK strategic portfolio prioritization, the Company received notice in October 2017 that GSK terminated the Agreement with respect to the third target, effective December 31, 2017, which returned all rights to that target to the Company. The two other targets, PRMT5 and PRMT1, continued to be subject to the Agreement and were not impacted by the termination with respect to the third target.