IGCS 2020 Annual Global Meeting – Abstract

Sep 2, 2020

Phase 1 Dose-Escalation Study of STRO-002, an anti-Folate Receptor alpha (FRα) Antibody Drug Conjugate (ADC), in Patients with Advanced Platinum Resistant/Refractory Epithelial Ovarian Cancer (OC).

Dr. Naumann is currently the Director of Minimally Invasive Surgery in Gynecologic Oncology and Professor in Department of Ob/Gyn at Carolinas Medical Center – Levine Cancer Institute in Charlotte, North Carolina. He did his residency in Obstetrics and Gynecology as well as his fellowship in Gynecologic Oncology at the University of Alabama School of Medicine in Birmingham. He has served as a board member on the Executive Council of the Society of Gynecologic Oncology (SGO) and the Chair of Education Committee and is currently the co-director of the SGO Winter meeting. He has an interest in chemotherapy development including targeted therapies and immune therapies and runs the phase I trials in gynecologic oncology at the Levine Cancer Institute. He and has served as a member of the GOG/NRG corpus committee and the Developmental Therapeutics committee.

R. Nauman, F. Braiteh, J.Diaz, E. Hamilton, S. Diab, R. Schilder, J.Moroney, L. Martin, D. Uyar, D. O’Malley, R. Penson, C. DiLea, M. Palumbo, V. DeAlmeida, C. Berman, S. Matheny, A. Molina

  1. Levine Cancer Institute, Carolinas Medical Center, Charlotte, NC, United States
  2. Comprehensive Cancer Centers of Nevada, Las Vegas, NV, United States
  3. Miami Cancer Institute at Baptist Health, Miami, FL, United States
  4. Sarah Cannon Research Institute, Tennessee Oncology PLLC, Nashville, TN, United States
  5. Rocky Mountain Cancer Center, Aurora, CO, United States
  6. Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, United States
  7. University of Chicago, Chicago, IL, UnitedStates
  8. University of Pennsylvania, Abramson Cancer Center, Philadelphia, PA, United States
  9. Medical College of Wisconsin, Milwaukee, IL, United States
  10. Ohio State University, Wexner Medical Center, Columbus, OH, United States
  11. Massachusetts General Hospital, Boston, MA, United States
  12. Aclairo Pharmaceutical Development Group, Vienna, VA, United States
  13. Sutro Biopharma, South San Francisco, CA, United States

Introduction: STRO-002 is a novel FRα-targeting ADC that delivers SC209, a potent tubulin- targeting hemiasterlin cytotoxin-warhead. Methods: All patients in the ongoing dose escalation study (NCT03748186) had platinum resistant/refractory OC without selection for FRα expression. STRO-002 is given IV on Day 1 of each 21-day cycle. Results: 38 patients have been dosed at 9 dose levels (0.5 to 6.4 mg/kg). Median number of cycles given is 3 (1-18). Median age is 61 (48-79). Median prior therapies – 5 (2-10). Clinically active doses (≥ 2.9 mg/kg) have been administered to 33 patients. 21/33 (64%) remain on treatment. Partial response was seen in 5 of 29 evaluable patients (17%) with 2 confirmed on second scan. 9 pts have confirmed SD for a clinical benefit rate of 48% (14/29). CA125 reduction of >50% was seen in 14/22 (64%) evaluable patients per GCIG. Clinical activity appears to be durable with 36% and 24% on study > 16 and > 24 weeks, respectively. 88% of AEs are grade 1 or 2. Grade 3-4 neutropenia, an expected and reversible effect of STRO- 002 occurred in 15/38 (39%). DLTs reported–grade 3 neuropathy (6.0mg/kg) and grade3 bone pain (6.4 mg/kg). Conclusions: STRO-002 is a novel FRα-targeting ADC with a promising emerging safety and efficacy profile and preliminary clinical benefit/disease control rate of 48% in patients with relapsed/refractory OC treated at ≥ 2.9 mg/kg. No ocular toxicity signals have been observed, suggesting potential differentiation from other FRα-targeting investigational therapies. Expansion cohorts in less heavily pre-treated patients are planned for 4Q20.