Checkmate Pharmaceuticals, Inc. (CMPI) SEC Filing 10-Q Quarterly Report for the period ending Thursday, September 30, 2021

Advancing patient recruitment activities and enrollment across our ongoing clinical trials evaluating vidutolimod, including:

A Phase 2 trial of vidutolimod in combination with nivolumab in anti-PD-1 refractory advanced melanoma, supported by a clinical collaboration with Bristol Myers Squibb.

A randomized Phase 2/3 trial of vidutolimod in combination with nivolumab vs. nivolumab monotherapy in first-line metastatic or unresectable melanoma, also supported by the clinical collaboration with Bristol Myers Squibb.

A Phase 2 trial of vidutolimod in combination with pembrolizumab in recurrent or metastatic squamous cell head and neck cancer. Interim data readouts anticipated beginning 1H 2022 and maturing throughout 2022.

Ongoing start-up activities for the planned expansion of the development program for vidutolimod into cutaneous squamous cell carcinoma and Merkel cell carcinoma, supported by a clinical collaboration with Regeneron to evaluate the combination of vidutolimod and Libtayo^® (cemiplimab).

Research and development expenses (R&D): R&D expenses for the three months ending June 30, 2021 were $14.9 million, compared to $6.5 million for the same period in the prior year. This increase reflected a milestone payment of $4.0 million in the second quarter of 2021 triggered by initiation of patient dosing in our refractory melanoma trial, as well as increases in personnel and operating expense for the planning and execution of additional clinical trials with vidutolimod.