Luvelta Demonstrates Promising Efficacy in Platinum-Resistant Ovarian Cancer Trial
核心洞察
Sutro Biopharma's luvelta achieved a 32% objective response rate (ORR) in patients with platinum-resistant ovarian cancer (搜索) (PROC) in the REFRαME-O1 trial.
The data confirms luvelta's efficacy across varying levels of Folate Receptor Alpha (FRα (搜索)) expression, potentially benefiting a broader patient population.
The safety profile of luvelta was favorable, with neutropenia (搜索) well-managed and no new safety concerns identified in the trial.
Sutro Biopharma's luveltamab tazevibulin (luvelta) has shown promising results in the dose-optimization portion (Part 1) of the REFRαME-O1 trial for patients with platinum-resistant ovarian cancer (搜索) (PROC). The data, announced December 10, 2024, highlights a 32% objective response rate (ORR) in evaluable patients at the selected 5.2 mg/kg starting dose, which will be used in the randomized portion (Part 2) of the ongoing registrational trial. These findings suggest luvelta could offer a significant clinical benefit for women with late-stage ovarian cancer (搜索).
REFRαME-O1 Trial: Part 1 Results
The REFRαME-O1 trial (Part 1) evaluated luvelta in PROC patients with varying Folate Receptor Alpha (FRα (搜索)) expression levels, including those with ≥25% Tumor Proportion Score (TPS). Patients were randomized 1:1 to either a 5.2 mg/kg dose with prophylactic pegfilgrastim (G-CSF) for two cycles followed by 4.3 mg/kg for subsequent cycles, or a 4.3 mg/kg dose for all cycles. The primary endpoint was objective response rate (ORR).
Key findings from the 5.2 mg/kg group (N = 25) include:
- An objective response rate (ORR) of 32%, including one confirmed partial response.
- A disease control rate of 96%.
- Approximately half of the patients were ineligible for approved FRα-targeting ADCs.
- 88% of patients had prior bevacizumab treatment.
- Grade 3 or higher neutropenia occurred in 32% of patients, with no febrile neutropenia reported.
Clinical Significance and Expert Commentary
"The clinical results from Part 1 of REFRαME-O1 provide compelling evidence that luvelta has the potential to be both first in class and best in class for patients who have low to medium expression of FRα (搜索). FRα is a validated target, and luvelta has the opportunity to reach more patients in need," said Bradley Monk, M.D., Florida Cancer Specialists and Research Institute; Director GOG Partners.
Wendel Naumann, M.D., Professor, Levine Cancer, Atrium Health/Wake Forest University, Charlotte, NC, added, "The topline safety profile of luvelta from Part 1 is encouraging. Neutropenia (搜索) rates were low, highlighting successful management guidelines. Furthermore, the lack of serious ocular damage, pancytopenia, or Interstitial Lung Disease provide further confidence in our ability to treat a broad group of women with PROC with a focus on their overall wellbeing."
REFRαME-O1: Part 2 and Future Directions
REFRαME-O1 (Part 2) is an ongoing global registrational trial evaluating a 5.2 mg/kg dose of luvelta with prophylactic pegfilgrastim (G-CSF) for the first two cycles, followed by 4.3 mg/kg for subsequent cycles. Part 2 will enroll approximately 500 patients, randomized 1:1 to luvelta or investigator's choice of chemotherapy. Sutro Biopharma is positioning luvelta for an Accelerated Approval application in mid-2027.
About Luveltamab Tazevibulin
Luveltamab tazevibulin (luvelta), formerly known as STRO-002, is an antibody-drug conjugate (ADC) targeting FRα (搜索). It is designed to treat a broad range of ovarian cancer (搜索) patients, including those with lower FRα expression who are not eligible for existing FRα-targeted therapies. Luvelta, developed using Sutro's XpressCF® platform, is a homogeneous ADC with four hemiasterlin cytotoxins per antibody, precisely positioned for efficient tumor delivery and systemic stability.