– Initiated enrollment in Phase 1B clinical trial of SL-172154 in combination with mirvetuximab soravtansine in platinum-resistant ovarian cancer –
– Dosed patients in first combination cohort with azacitidine in ongoing Phase 1A/B clinical trial of SL-172154 in acute myeloid leukemia (AML) and higher-risk myelodysplastic syndromes (HR-MDS) –
– Announced two potential lead product candidates, currently in preclinical development, from the Gamma Delta T Cell Engager (GADLEN) platform –
– Appointed Dr. George Fromm and Dr. Suresh de Silva as Chief Scientific Officers (CSO) of the ARC and GADLEN platforms, respectively –
– Completed Phase 1 dose-escalation trial of SL-279252 and announces discontinuation of the SL-279252 program –
AUSTIN, TX and DURHAM, NC, Feb. 23, 2023 (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, today reported financial results for the fourth quarter and full year ended December 31, 2022 and provided recent business highlights.
“During the fourth quarter of 2022, we continued to focus on clinical execution to position ourselves for key clinical data readouts for SL-172154 in 2023. Enrollment in our AML/HR-MDS clinical trial of SL-172154 is moving along nicely, and, in the fourth quarter, we advanced into the first combination cohort with azacitidine. This keeps us on track to share initial data from the dose-escalation portion of this trial from relapsed/refractory AML/HR-MDS patients both as monotherapy and in combination with azacitidine in the first half of 2023. As it relates to our trials in platinum-resistant ovarian cancer, in early 2022 we established a collaboration with ImmunoGen to combine SL-172154 with mirvetuximab soravtansine and, in the fourth quarter, we initiated enrollment in this Phase 1B clinical trial. We expect initial data from the combination trial with SL-172154 and liposomal doxorubicin midyear 2023, and we expect initial data from the combination trial of SL-172154 and mirvetuximab soravtansine in the second half of 2023,” said Taylor Schreiber, M.D., Ph.D., and Chief Executive Officer of Shattuck. “I am also very pleased to announce the promotion of Dr. George Fromm to CSO of the ARC platform and Dr. Suresh de Silva to CSO of the GADLEN platform. We look forward to benefiting from the expertise of these scientific program leaders as we continue our momentum in 2023. Drs. Fromm and de Silva have been invaluable to Shattuck from the time they each joined the company in 2017, and they will continue to play a critical role as we build-out our pipeline over the coming years. 2023 is an important year for Shattuck, with multiple data readouts, which we believe will establish SL-172154 as both a differentiated CD47 inhibitor and a CD40 agonist capable of activating the CD40 pathway in human cancer patients. We expect that these data will position Shattuck well for continued growth in the years ahead.”
“After enrolling patients in the final dose levels of 12 and 24 mg/kg with the SL-279252 clinical program, and not meeting a stringent efficacy threshold required to justify further development, we have decided to discontinue development of SL-279252. The development program for SL-279252 has yielded tremendously important preclinical, translational, and clinical data for the ARC platform, and we thank the patients and their families for participating in our clinical trial. We remain focused on delivering novel therapeutics that benefit patients with cancer with high unmet need and look forward to the combination data in both of our ongoing clinical trials with SL-172154 in the coming quarters,” continued Dr. Schreiber.
Clinical Milestones Expected in 2023
ARC Platform
SL-172154 (SIRPα-Fc-CD40L)
- Complete data from Phase 1A dose-escalation clinical trial of SL-172154 as monotherapy in platinum-resistant ovarian cancer expected midyear 2023
- Initial data from Phase 1B clinical trial of SL-172154 in combination with liposomal doxorubicin in platinum-resistant ovarian cancer expected midyear 2023
- Initial dose-escalation data, as monotherapy and in combination with azacitidine, for Phase 1A/B clinical trial of SL-172154 in relapsed/refractory AML and HR-MDS expected in the first half of 2023
- Complete dose-escalation data, as monotherapy and in combination with azacitidine, for Phase 1A/B clinical trial of SL-172154 in AML and HR-MDS and initial dose-expansion cohort data with SL-172154 in combination with azacitidine in frontline TP53 mutant AML and HR-MDS expected in the second half of 2023
- Initial data from Phase 1B clinical trial of SL-172154 in combination with mirvetuximab soravtansine in platinum-resistant ovarian cancer expected in the second half of 2023
GADLEN Platform
GADLEN Preclinical Compounds
- Additional detail and further program guidance regarding the advancement of potential product candidates from the GADLEN platform expected in 2023
Fourth Quarter 2022 Recent Business Highlights and Other Recent Developments
ARC Clinical-Stage Pipeline
SL-172154 (SIRPα-Fc-CD40L)
- Completed Phase 1A Monotherapy Dose-Escalation Clinical Trial of SL-172154 in Platinum-Resistant Ovarian Cancer: This open-label, multi-center, dose-escalation clinical trial evaluated the safety, tolerability, pharmacokinetics, anti-tumor activity, and pharmacodynamic effects of SL-172154 administered intravenously in patients with advanced platinum-resistant ovarian cancer. We reached a maximum administered dose of 10.0 mg/kg and expect to present complete dose-escalation data from the trial midyear 2023.
- Dosed First Patients in First Combination Cohort with Azacitidine in Ongoing Phase 1A/B Clinical Trial in AML and HR-MDS: This trial is evaluating the safety, tolerability, pharmacokinetics, anti-tumor activity, and pharmacodynamic effects of SL-172154 as both monotherapy and in combination. In AML, SL-172154 may be evaluated in combination with azacitidine and venetoclax. In both HR-MDS and TP53 mutant AML, SL-172154 may be evaluated in combination with azacitidine. Patients have been dosed in both the monotherapy and combination dose-escalation cohorts of this trial and enrollment is ongoing. Dose escalation will continue in a parallel staggered manner, and initial dose-escalation data, as monotherapy and in combination with azacitidine, are expected in the first half of 2023.
- Enrollment Progressing in Phase 1B Clinical Trial of SL-172154 in Combination with Liposomal Doxorubicin in Advanced Platinum-Resistant Ovarian Cancer: Enrollment is continuing in this trial, which is evaluating the safety, tolerability, pharmacokinetics, anti-tumor activity, and pharmacodynamic effects of SL-172154, using the selected dose of 3.0 mg/kg, in combination with liposomal doxorubicin in patients with advanced platinum-resistant ovarian cancer. We expect to present initial data from this trial in combination with liposomal doxorubicin midyear 2023.
- Initiated Enrollment in Phase 1B Clinical Trial of SL-172154 in Combination with Mirvetuximab Soravtansine in Advanced Platinum-Resistant Ovarian Cancer. This trial is evaluating the safety, pharmacokinetics, pharmacodynamic effects, and preliminary anti-tumor activity of SL-172154 administered in combination with mirvetuximab soravtansine in subjects with platinum-resistant ovarian, primary peritoneal, or fallopian tube cancers. Mirvetuximab soravtansine is an antibody-drug conjugate targeting folate receptor alpha, or FRα, which provides for both direct tumor cell killing as well as enhanced macrophage phagocytosis through binding with Fc gamma receptors and has received accelerated approval for platinum-resistant ovarian cancer patients whose tumors are shown to be FRα positive, defined as ≥75%, as determined by the VENTANA FOLR1 (FOLR1-2.1) Assay, using the PS2+ scoring method. Pre-clinical studies have shown that both of these killing mechanisms are complementary to the mechanism of SL-172154 by enhancing the activity of macrophages to phagocytose FRα- expressing ovarian cancer cells, and that SL-172154 may broaden the activity of mirvetuximab soravtansine, particularly in patients with tumors that express lower levels of FRα. We intend to enroll patients with broader FRα expression, including those with “high” (greater than ≥75% of tumor cells staining with 2+ intensity), “medium” (≥50% to