Objective responses, good safety and evidence of stimulation of the immune system were observed with GM102 administered as a single agent in the dose-finding escalation part of the study

PARIS and TOULOUSE, France I May 22, 2018 I GamaMabs Pharma, a biotechnology company developing optimized therapeutic antibodies targeting the Anti-Müllerian Hormone Receptor II (AMHRII) for the treatment of cancer, today announces the upcoming presentation of clinical data from the First-In-Human C101 phase Ia/Ib study of its GM102 antibody during the American Society of Clinical Oncology (ASCO) Annual Meeting, on June 4 in Chicago, USA.

Data will be reported on 27 patients with advanced or recurrent AMHRII-positive epithelial ovarian (EOC), granulosa ovarian (GCT), cervical and endometrial cancers, treated with GM102 monotherapy in eight successive escalation cohorts at five major European cancer centers

No safety signal was reported at all doses tested. Two clinical objective partial responses according to RECIST criteria were observed among four GCT patients. Peripheral blood pharmacodynamic changes observed under GM102 treatment suggested an immune cell recruitment to the tumor site. In paired tumor biopsies before and under GM102 treatment, enhanced CD16 and Granzyme B biomarker expression was observed in the tumor micro-environment, suggesting GM102-induced cellular cytotoxicity or phagocytosis.

Expansion cohorts in EOC and GCT at the recommended GM102 dose are currently ongoing, with first results anticipated early 2019

GM102 is a first-in-class glyco-engineered (low-fucose) monoclonal antibody selectively targeting AMHRII-expressing tumors. AMHRII, an embryonic receptor involved in the regression of the Müllerian ducts in the male embryo, is constitutively expressed in ovarian granulosa tumors (GCT) and re-expressed in approximately 70% of gynecological tumors. GM102 exerts its anti-tumor activity through NK cell and macrophage engagement in the tumor microenvironment, resulting in enhanced tumor phagocytosis and ADCC (Antibody Dependent Cell Cytotoxicity).

“These first results are really encouraging, especially for patients with granulosa ovarian cancers who do not have therapeutic alternatives at this stage,” said Pr. Alexandra Leary, Gustave Roussy Institute (France), principal investigator of the study. “We are gathering experience with additional patients in the expansion part of the study; should these first results be confirmed, we will move forward with a larger phase 2 study in this indication with great enthusiasm, given the unmet medical need.”

“We are happy to share such exciting data with the medical community, which confirm the unique immunological mode of action of GM102 and shows its translation into clinical activity,” said Stéphane Degove, CEO at GamaMabs Pharma. “We are expanding our GM102 clinical development program beyond the field of gynecological cancers in other tumor types that also express AMHRII,” he added.

Results will be presented at the ASCO Annual Meeting in Chicago, during the Gynecologic Cancer session, on June 4, 2018, 1:15 PM-4:45 PM.

Abstract #5542; Poster ID 214461, ‘A first-in-human study of monoclonal antibody GM102 in patients with Anti-Mullerian-Hormone-Receptor II (AMHRII) positive gynecological cancers’ by A Leary and co-authors.

Following the presentation, the poster will be available on the Publication page of GamaMabs’ website

About GamaMabs Pharma

GamaMabs Pharma, a French immuno-oncology biotechnology company, is a leader in the development of optimized antibodies targeting AMHRII for the treatment of cancer. GamaMabs’ first-in-class proprietary therapeutic monoclonal antibodies have the potential for broad applications in cancer. GM102 antibody, which targets the Anti-Müllerian Hormone Receptor II (AMHRII/MISR2), entered into the clinic in H1 2016 with a first trial in gynecological cancers. The company develops low-fucose EMABling® antibodies (license granted by LFB) with increased tumor cell killing properties through a breakthrough activation of immune cells. GamaMabs also has a licensing agreement with MedImmune (USA) to develop an Antibody Drug Conjugate targeting cancer. www.gamamabs.com

SOURCE: GamaMabs Pharma