TORL BioTherapeutics has closed a $96 million Series C financing round to advance its lead antibody-drug conjugate TORL-1-23 through pivotal clinical trials for platinum-resistant ovarian cancer. The funding brings the company's total capital raised since its 2019 founding to over $450 million, positioning it to pursue accelerated registration of its Claudin 6 (CLDN6)-targeted therapy.
The proceeds will primarily fund CATALINA-2, the ongoing pivotal Phase 2 study of TORL-1-23 in CLDN6-positive patients with platinum-resistant ovarian cancer (PROC), targeting a pivotal data readout in 2027. Additionally, the financing will support CATALINA-3, a confirmatory Phase 3 study scheduled to initiate in 2026.
Clinical Development Milestones
TORL-1-23 has received Fast Track Designation from the U.S. Food and Drug Administration and is being evaluated as a first- and potentially best-in-class ADC for CLDN6-positive solid tumors. The company will present updated Phase 1 data at the 2025 European Society of Medical Oncology Congress (ESMO 2025) in Berlin, Germany.
The ongoing Phase 1 study enrolled patients with heavily pretreated CLDN6-positive ovarian, testicular, endometrial, non-small cell lung and other cancers across multiple dose cohorts. According to the company, emerging efficacy data from this study supported the decision to advance TORL-1-23 into larger, registrational studies.
"This financing ensures TORL is able to further the clinical development of TORL-1-23, our first- and potentially best-in-class Claudin 6 targeted ADC for women living with platinum-resistant ovarian cancer," said Mark J. Alles, Chairman and Chief Executive Officer of TORL BioTherapeutics.
CATALINA-2 Study Design
CATALINA-2, initiated in November 2024, is designed to support accelerated registration of TORL-1-23 for CLDN6-positive PROC. The global, multi-institutional, randomized, open-label Phase 2 study will enroll women with CLDN6-positive PROC who have received one to three prior lines of therapy.
The primary endpoint is objective response rate (ORR) per RECIST v1.1 by blinded independent central review. Secondary endpoints include duration of response, ORR by investigator assessment, progression-free survival, overall survival and safety.
Targeting Claudin 6
Claudin 6 represents an attractive therapeutic target due to its overexpression in several cancers with limited to no detectable expression in normal tissues. CLDN6 is a transmembrane protein that normally occurs during embryonic and fetal development but not in adult tissues. Its overexpression occurs in specific malignancies including ovarian, non-small cell lung, endometrial and testicular cancers, with high expression correlating with shortened survival outcomes for patients with ovarian cancer.
"The maturing clinical profile of TORL-1-23 continues to demonstrate the potential to improve treatment outcomes for patients with CLDN6+ platinum-resistant ovarian cancer, a defined subset of the disease with particularly poor prognosis," said Scientific Co-founder and Board Member Dennis Slamon, MD, PhD, Professor of Medicine, and Chief of the Division of Hematology/Oncology at UCLA's David Geffen School of Medicine.
Strategic Partnership and Pipeline
TORL operates through a strategic partnership with the Slamon Research Lab at UCLA, providing the company with exclusive development and commercial rights to a large program of biologics-based drugs targeting novel cancer targets. The financing will also support registration-enabling Phase 2 and Phase 3 studies, ongoing Phase 1 studies, and IND-enabling work across TORL's pipeline of novel high-value targets in solid tumors and hematologic malignancies.
