Synimmune’s anti-tumor Flysyn verywell tolerated in study

Synimmune GmbH, a biotechnology company focusing on the development of innovative and effective anti-tumor antibodies for orphan hematopoietic malignancies, presented results of its first-in-human clinical study of Flysyn, a novel Fc-optimized antibody, for the treatment of acute myeloid leukemia, which was well tolerated in a study.

The phase I study of Flysyn results (AML) were presented at the American Society of Hematology (ASH) Annual Meeting in Orlando, Florida. It is being conducted at multiple centers in Germany (University Hospitals of Tübingen, Ulm, Heidelberg, Hanover and Leipzig) and will enroll up to 31 AML patients that have achieved a complete morphological remission but display minimal residual disease (MRD). The poster reports on an interim analysis of 21 adult patients (median age: 60 years) who were treated in 5 cohorts receiving a single administration of increasing doses of Flysyn (0.5 to 45 mg/m² body surface area).

Synimmune said Flysyn was very well tolerated and only one patient experienced grade 3 neutropenia which was potentially related to Flysyn treatment. Other adverse events of grade 1 or 2 included gastrointestinal toxicities and laboratory abnormalities which were manageable with supportive care. No dose limiting toxicities occurred during the dose-escalation phase and no anti-drug antibodies were detected after treatment, Synimmune said in the press release.

A total of 7 patients (33%) achieved an MRD response defined as a log reduction of expression of an MRD marker gene and one patient achieved an enduring complete molecular remission (MRD negative) for more than one year.

“Our data indicate that Flysyn is safe and very well tolerated. The preliminary efficacy data are promising. We are very much looking forward to further test Flysyn as monotherapy for MRD positive AML patients,” said Prof. Helmut Salih, Principle Investigator of the study and Medical Director of the Clinical Collaboration Unit Translational Immunology at Tübingen University Hospital.

Dr. Martin Steiner, CEO of Synimmune GmbH, said that the results are very encouraging and further results are expected, from the last treatment cohort of 10 patients who will receive three repetitive doses of 15 mg/m² body surface area of Flysyn by mid-2020. He reminded that the majority of AML patients with MRD relapse within several months. He said: “We are looking forward to continue development of Flysyn, which is intended to delay or even prevent such relapse, and we believe that Flysyn could become an attractive maintenance treatment option for many AML patients.”