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SHATTUCK LABS Shattuck Labs Reports Third Quarter 2021 Financial Results and Recent Business Highlights November 9 , 2021 - Announced initial Phase 1 dose - escalation data from SL - 172154 in ovarian cancer and SL - 279252 in solid tumors at the Society for Immunotherapy of Cancer ( SITC ) annual meeting ; both clinical trials remain ongoing- -SL - 279252 ( PD1 - Fc - OX40L ) demonstrates anti - tumor activity and evidence of dose - dependent immune activation in heavily pretreated , checkpoint experienced patients - -SL - 172154 ( SIRPα - Fc - CD40L ) demonstrates high levels of CD47 target occupancy and evidence of dose - dependent CD40 - mediated immune activation - - Open IND for clinical trial of SL - 172154 in acute myeloid leukemia ( AML ) and higher - risk myelodysplastic syndromes ( HR - MDS ) – - - Shattuck and Takeda mutually agree to terminate Collaboration Agreement ; Shattuck regains rights to clinical - stage product candidate SL - 279252 - -Shattuck Labs to host conference call and webcast on November 12 at 8:00 a.m. EST- AUSTIN , TX and DURHAM , NC , Nov. 09 , 2021 ( GLOBE NEWSWIRE ) -- Shattuck Labs , Inc. ( Shattuck ) ( NASDAQ : STTK ) , a clinical - stage biotechnology company pioneering the development of bi - functional fusion proteins as a new class of biologic medicine for the treatment of patients with cancer and autoimmune disease with three ongoing Phase 1 clinical trials , today reported financial results for the third quarter ended September 30 , 2021 , and provided recent business highlights . " We designed the ARC platform to simultaneously block immune checkpoint targets and activate immune costimulatory receptors in the TNF superfamily . The clinical data presented this week at SITC demonstrate evidence of anti - tumor activity , target receptor binding , and dose - dependent immune activation specific to each of CD40 and OX40 , " said Taylor Schreiber , M.D. , Ph.D. , and Chief Executive Officer of Shattuck . " Both compounds have been well tolerated and are demonstrating predictable dose - response relationships in humans . The doses we have explored to date remain below the recommended Phase 2 doses of benchmark CD47 inhibitors and PD - L1 inhibitors , and we look forward to continuing dose escalation of both SL - 172154 and SL - 279252 into dose levels that we believe will maximize the pharmacodynamic activity and anti - tumor activity of each compound . " " We are very encouraged by the initial data from the Phase 1 trial of SL - 172154 . The data show an excellent safety profile , high CD47 receptor occupancy and clear evidence of CD40 engagement , which collectively differentiate SL - 172154 from other CD47 inhibitors , " said Nehal Lakhani , M.D. , Ph.D. , South Texas Accelerated Research Therapeutics ( START ) Midwest , Grand Rapids , MI . " We desperately need new therapies for late - stage ovarian cancer patients , particularly in the platinum resistant setting . The combined actions of CD47 inhibition and CD40 activation provided by SL - 172154 represents a strategy that has not yet been examined in this disease and may initiate anti - tumor immune responses that could provide lasting benefits in late - stage ovarian cancer . " " SL - 172154 is emerging as a highly differentiated CD47 inhibitor . The clinical data indicate that this compound can safely engage CD40 in a manner that has evaded other CD40 - targeted biologics for over twenty years . At the same time , we can compare and contrast the relative potency of CD40 versus OX40 activation , and the clinical data indicate that CD40 targeting provides substantially more immunologic activity than OX40 activation . There are some parallels to these observations in the checkpoint space , where blockade of targets like LAG3 , TIM3 , and TIGIT has been far more subtle than blockade of CTLA - 4 or PD - 1 , " continued Dr. Schreiber . " The current data suggests that we may be coming close to a recommended Phase 2 dose selection for SL - 172154 as monotherapy . We are excited to transition to the combination with liposomal doxorubicin in ovarian cancer , and with azacitidine and venetoclax in AML , and azacitidine in higher - risk MDS and TP53 mutant AML . More importantly , these data help to establish the ARC platform more broadly as a novel class of biologic medicine , which opens opportunities for the rest of our vast pipeline of candidates developed internally at Shattuck . " Third Quarter 2021 Recent Business Highlights and Other Recent Developments Agonist Redirected Checkpoint ( ARC ) Platform Clinical - Stage Pipeline • Initial Data from Ongoing SL - 172154 ( SIRPα - Fc - CD40L ) Phase 1 Dose - Escalation Clinical Trial in Platinum Resistant Ovarian Cancer Demonstrate Favorable Safety Profile and High Target Occupancy at the 36th Annual SITC Meeting : The Phase 1 trial is an open - label , multi - center , dose - escalation study to evaluate the safety , tolerability , pharmacokinetics , anti - tumor activity , and pharmacodynamic effects of SL - 172154 administered intravenously in patients with platinum resistant ovarian cancer . Shattuck will continue dose escalation to 10mg / kg . • Data reported at SITC was in 14 evaluable patients as of July 6 , 2021 , across four dose levels on two schedules : schedule 1 ( day 1 , 8 , 15 , 29 , then every two weeks ) at 0.1 , 0.3 mg / kg and schedule 2 ( weekly ) at 0.3 , 1.0 , 3.0 mg / kg . To date , no dose limiting toxicities have been observed . • Preliminary pharmacodynamic parameters for SL - 172154 demonstrate on - target , CD40 - mediated immune activation . The binding of SL - 172154 to CD40 + B cells and monocytes led to rapid activation and margination of these cells post infusion .