A phase I, multicenter trial (“KinLET�) of [177Lu]Lu-edotreotide for treatment of somatostatin receptor positive solid tumors or lymphoma, in patients two to less than 18 years of age

BackgroundTargeted Radiopharmaceutical Therapy (RPT) with [177Lu]Lu-edotreotide is being explored as treatment option for patients with relapsed/refractory somatostatin receptor (SSTR)-positive tumors, including neuroendocrine tumors, CNS-tumors, lymphoma, rhabdomyosarcoma, peripheral primitive neuroectodermal tumors and gastrointestinal sarcoma tumors.Trial designKinLET is an open-label, multicenter, phase I trial aiming to determine the appropriate dose based on the safety profile and the pharmacokinetics (PK) of [177Lu]Lu-edotreotide targeted RPT in pediatric patients with SSTR-positive tumors. Further objectives include the assessment of preliminary anti-tumor activity by tumor type, safety and dosimetry evaluations. Up to 100 MBq/kg or 7.5 GBq/75 kg for each treatment cycle will be studied. Dosage of [177Lu]Lu-edotreotide will be adjusted based on the patient's weight as well as dosimetry in a subset of patients and applied sequentially in each cohort to not exceed a total absorbed dose of 23 Gy and 2 Gy to kidneys and bone marrow, respectively. [177Lu]Lu-edotreotide dosimetry is planned to be evaluated by single-photon emission computed tomography/low dose computed tomography; whole body planar imaging and blood radioactivity measurements at specific intervals, along with safety and preliminary efficacy parameters. It is planned to include at least 20 participants in three sequential age cohorts: (1) ≥12 to <18 years old; (2) ≥6 years to <12 years old; (3) ≥2 to <6 years old (minimum of six participants in each age cohort). The opening of the 2nd and 3rd cohort will depend on the recruitment of at least four participants with dosimetry and safety data for cycle 1 of the previous cohort. Treatment will comprise two to six [177Lu]Lu-edotreotide treatment cycles every eight weeks. Tumor assessment and follow-up evaluation by anatomical and functional imaging is performed within the treatment period and the first two years of the five-year follow-up. Due to the rare incidence of SSTR-positive tumors in pediatric patients, patient recruitment is a key element in this trial.Editorial acknowledgementMargret I. Moré.Legal entity responsible for the studyITM Solucin GmbH.FundingITM Solucin GmbH.DisclosureS. Melnyk, T. Thevenet: Financial Interests, Institutional, Full or part-time Employment: ITM Isotope Technologies Munich SE. A. Rotger: Financial Interests, Institutional, Financially compensated role: ITM Isotope Technologies Munich SE. All other authors have declared no conflicts of interest.