• First four dose escalation levels completed showing excellent tolerability for CTL-002 in monotherapy and combination with nivolumab; fifth and highest dose level evaluation ongoing
  • Preliminary pharmacodynamic analyses at early dose levels suggest CTL-002-mediated selective T cell relocation into the tumor and tumor stroma/microenvironment; further analyses are under way

MUNICH, Germany I October 11, 2021 I CatalYm, today announced an update from the dose escalation part of the ongoing first-in-human trial “GDFather” (GDF-15 Antibody-mediated Effector cell Relocation) investigating its lead product candidate, CTL-002, both in monotherapy and in combination with an immune checkpoint inhibitor, nivolumab. CTL-002 is a neutralizing antibody that specifically targets growth and differentiation factor 15 (GDF-15), which is recognized as a negative regulator of antitumoral T cell activity preventing T cell recruitment to the tumor microenvironment as well as potently suppressing an adaptive immune response by additional mechanisms recently identified. Patients treated with CTL-002 and nivolumab at the first four of five dose levels to be evaluated showed an excellent tolerability profile and no dose limiting toxicities (DLT). Preliminary sequential tumor biopsy analyses for dose level 1-3 showed signs for a tumor-selective influx of T cell under CTL-002 treatment. GDFather is the most advanced clinical trial of a GDF-15-targeting therapeutic in immuno-oncology. The data was presented in an oral presentation at the plenary session ‘New Drugs on the Horizon II’ at the 2021 AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics, on October 9, 2021.

Prof. Dr. Eugen Leo, Chief Medical Officer at CatalYm commented, “GDF-15 has been recently identified by us and others as a tumor-derived key negative regulator of the immune response against cancer. We are delighted to see the excellent tolerability of CTL-002 in combination with nivolumab and initial evidence for targeted activity from dose level 1 onwards, which is reflected by induction of a tumor-selective influx of T cells. Additional biomarker analyses and relevant data for all cohorts will be available before year-end and we are very keen to take this drug forward into the next stage of clinical development to serve the anti-PD1/PD-L1 refractory patient population, which represents a significant number of patients in many solid tumors.”

Dr. Phil L’Huillier, Chief Executive Officer at CatalYm added, “The opportunity to provide this data update at the “New Drugs on the Horizon” plenary session of the ACR-NCI-EORTC conference reflects the scientific innovation and clinical relevance presented by our approach. Although the data is still preliminary at this stage, it corroborates our preclinical data and confirms the proposed mode of action of CTL-002. Our ultimate goal is to provide meaningful clinical benefit to a patient population with very poor prognosis, refractory to checkpoint inhibitors and all other standard of care treatments. We look forward to further evaluating CTL-002 in this heavily pretreated patient population.”

The ongoing first-in-human GDFather trial (GDF-15 antibody-mediated effector cell relocation) consists of two parts. In the dose escalation phase (Part A), up to 24 patients will receive escalating doses of CTL-002 in a “3+3” manner with the lead candidate given as a monotherapy and followed by combination with an anti-PD-1 checkpoint inhibitor. In the second dose expansion phase (Part B, phase 2a), several cohorts with tumors identified to be GDF-15-dependent will be treated to further evaluate safety and preliminary efficacy of CTL-002 treatment. Additional biomarker data, safety information and first efficacy readouts from all dose levels tested in dose escalation of CTL-002 both for monotherapy and in combination with nivolumab may be available by year-end.

About CTL-002

CTL-002 is a humanized, monoclonal antibody designed to neutralize the tumor-produced Growth Differentiation Factor-15 (GDF-15). GDF-15 secretion by the tumor has been shown to prevent T cell migration into the tumor and suppresses T cell function and the adaptive immune response in the tumor microenvironment. This enables the tumor to evade the immune system and become resistant to standard of care and current immunotherapy approaches such as checkpoint inhibitors. CTL-002 counteracts these immuno-suppressive mechanisms by neutralizing GDF-15, enhancing the infiltration of immune cells into the tumor, improving both priming of T cells by dendritic cells and tumor killing by T cells and NK cells.

About CatalYm

CatalYm has identified GDF-15 as a central regulator of the immune system in the tumor microenvironment. We are pioneering the reversal of GDF-15-mediated immunosuppression to induce a potent antitumoral immune reaction in non-responsive tumors. CatalYm’s lead program CTL-002 is poised to demonstrate clinical proof-of-concept in multiple solid tumor indications which will expand the treatment horizon for current and future immunotherapies.