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REPARE THERAPEUTICS Repare Therapeutics Provides Business Update and Reports First Quarter 2021 Financial Results May 13 , 2021 Introduced PKMYT1 as synthetic - lethal target for tumors with CCNE1 amplification or FBXW7 loss and highlighted program progress at RP - 6306 Virtual Investor Day Event Announced enrollment of first patient in RP - 6306 Phase 1 clinical trial Activated 10 clinical trial sites across North America and Europe for the PARP - inhibitor combination arm of the RP - 3500 TRESR Phase 1/2 clinical trial CAMBRIDGE , Mass . & MONTREAL -- ( BUSINESS WIRE ) -- May 13 , 2021-- Repare Therapeutics Inc. ( " Repare " or the " Company " ) ( Nasdaq : RPTX ) , a leading clinical - stage precision oncology company enabled by its proprietary synthetic lethality approach to the discovery and development of novel therapeutics , today reported financial results for the first quarter ended March 31 , 2021 . " We have advanced the Phase 1/2 clinical development of our ATR inhibitor RP - 3500 , with initial results expected from the monotherapy arm of the trial in the second half of 2021. The PARP inhibitor and RP - 3500 combination arm is now recruiting , " said Lloyd M. Segal , President and Chief Executive Officer of Repare . " We are pleased that the first patient has been dosed in our Phase 1 clinical trial of RP - 6306 , materially ahead of the timeline we disclosed at the time of our IPO last June . " First Quarter 2021 Review and Operational Updates : • Highlighted program progress and introduced PKMYT1 as synthetic - lethal target to CCNE1 and FBXW7 at RP - 6306 Virtual Investor Day Event . • In April 2021 , the Company highlighted pre - clinical anti - tumor activity of RP - 6306 , a potential first - in - class small molecule product candidate targeting PKMYT1 , which is synthetic lethal with CCNE1 amplification , FBXW7 loss , and potentially other genomic alterations . • Announced enrollment of first patient in RP - 6306 Phase 1 clinical trial . • In April 2021 , the Company dosed the first patient in its Phase 1 clinical trial of RP - 6306 . o The trial ( NCT04855656 ) is expected to enroll approximately 60 patients with recurrent tumors characterized by genomic alterations predicted by the Company's SNIPRX® CRISPR - based platform to be sensitive to RP - 6306 . • The trial objectives include assessment of safety , tolerability , dose and schedule ( including the establishment of a recommended Phase 2 dose ) . o Subject to completion and review of the Phase 1 clinical trial , the Company expects to advance RP - 6306 , both as monotherapy and in combination with chemotherapies and other agents , into proof - of - concept trials in 2022 targeting a variety of patient populations , including those with tumors with CCNE1 amplification , FBXW7 loss or other undisclosed alterations identified through its proprietary STEP² screen . • Prospective enrichment of patient trial populations will be guided by the Company's ongoing efforts to develop patient selection , target engagement and functional biomarkers . • Initiated patient recruitment of PARP - inhibitor combination arm of the RP - 3500 TRESR Phase 1/2 clinical trial . • Repare has activated 10 clinical trial sites across North America and Europe , and is actively recruiting patients to evaluate RP - 3500 in a combination arm with Pfizer's PARP inhibitor , talazoparib , in addition to a monotherapy arm . • Initial results are expected to be reported from the monotherapy arm of the trial in the second half of 2021 . First Quarter 2021 Financial Results : • Cash and cash equivalents , restricted cash and marketable securities : Cash and cash equivalents , restricted cash and marketable securities as of March 31 , 2021 were $ 319.1 million . • Research and development expenses , net of tax credits ( Net R & D ) : Net R & D expenses were $ 16.5 million and $ 8.6 million for the quarters ended March 31 , 2021 and 2020 , respectively . The increase in R & D expenses year - over - year was primarily due to increases in development costs related to the Company's RP - 3500 and RP - 6306 programs , as well as increases in personnel related expenses , including stock - based compensation , and certain other R & D expenses . • General and administrative ( G & A ) expenses : G & A expenses were $ 5.2 million and $ 2.2 million for the quarters ended March 31 , 2021 and 2020 , respectively . The increase in G & A expenses year - over - year was due to increases in personnel related costs , including stock - based compensation , and D & O insurance which increased as a result of the Company's transition to a public company . • Net loss : Net loss was $ 21.4 million , or $ 0.58 per share in the quarter ended March 31 , 2021 and $ 12.6 million , or $ 7.71 per share , in the quarter ended March 31 , 2020 .