Genmab A/S announced positive results from a phase I study of R1507 in patients with solid tumours, conducted by its partner Roche. R1507 is a human monoclonal antibody targeting the insulin-like growth factor receptor (IGF-1R) and was developed under Roche's collaboration with Genmab.
Nine of 34 adult patients with solid tumours experienced disease stabilization when treated with R1507. Four of the seven heavily pre treated patients with Ewing's sarcoma demonstrated clinical benefit with two of these patients achieving durable, objective partial responses.
Once a week administration of R1507 was well tolerated with few side effects. The most frequently observed side effects were fatigue, anorexia and weight loss, symptoms that are commonly observed in patients with advanced cancer. A similar side effect profile was seen in 26 patients who were treated with R1507 on a three week schedule.
The results were reported during the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics in San Francisco, California, USA.
"These are the first clinical results to be presented from an antibody developed by Genmab under our collaboration with Roche. We are pleased with these positive results and hope it may offer a potential treatment for sarcoma patients in the future," said Lisa N. Drakeman, Ph.D.
Based on these initial results with R1507, Roche plans to conduct additional trials and work with a global consortium of sarcoma experts, including the Sarcoma Alliance for Research through Collaboration (SARC).
IGF-1 is one of the most potent natural activators of the AKT and MAPK signaling pathways, which promote cell growth and cell survival. The IGF-1R pathway has also been shown to have an important role in mediating the resistance to cytotoxic drugs and EGFR/HER2-targeted agents. The IGF-1R molecule has been shown to be important in tumour growth and protecting tumour cells from being killed. IGF-1R is over-expressed on a variety of tumours including breast, colon, prostate, lung, skin and pancreatic cancers and is a well validated target for an antibody therapeutic approach.
The Ewing's family of tumours (EFT) includes primary tumours of bone (classic Ewing's sarcoma, primitive neuroectodermal tumour, and Askin tumour) and extraosseous primary tumours. The estimated incidence of Ewing's sarcoma in the US is approximately 300 new cases per year. More than 50 per cent of patients are adolescents with a slight predominance in males. Patients who present with metastatic disease at initial diagnosis have a survival rate of approximately 25 to 30 per cent.