Tarlatamab + Radiation Therapy

Tarlatamab will be administered at a step-up dose of 1mg on Cycle 1 Day 1 and then 10 mg on Cycle 1 Day 8 and Cycle 1 Day 15 and every 2 weeks thereafter. For cycle 2 onwards, tarlatamab infusion will occur every 2 weeks on days 1 and 15 of each cycle.

Standard of care RT can begin as early as Cycle 1 Day 16 and as late as Cycle 2 Day 28, assuming there is no ongoing CRS (extracranial)/ICANS (cranial).

This is a Phase I, Open label, Single Arm, Multi-center Study, with nested Phase II to examine safety of standard palliative and consolidative RT regimens in a main cohort of patients with tumor histologies with high prevalence of DLL3 (N=20-24) with an extracranial site (primary or metastatic) amenable to radiation (not allowing for re-irradiation of the same lesion, with a minimum of 10 thoracic sites.

Phase I study to examine safety of the addition of concurrent tarlatamab with standard palliative and consolidative RT regimens , with a main cohort of N=20-24 patients with extracranial anatomic radiation sites.

I) After lead in of 10 patients demonstrating safety of treatment, allow for expansion to cranial sites of disease (N=6-10) with continued enrollment in main cohort II) If toxicity criteria is not met in concurrent RT tarlatamab cohort, we will continue with sequential RT, either A) delivered within 7 days prior to cycle 1 day 1, or B) delivered during cycle 1 -2 but with pre- and post-RT washout of 7 days with no drug during RT, to examine safety in a temporally spaced setting.

Live record on ClinicalTrials.gov →

• Subject has provided informed consent/assent prior to initiation of any study specific activities/procedures.
• Subjects ≥ 18 years of age at the time of signing the informed consent.
• Other tumors of small cell histology
• High grade / poorly differentiated neuroendocrine histology tumor histologies with high prevalence of DLL3 (≥50% prevalence of ≥1% positivity), including but not limited to: melanoma, medullary thyroid cancer, esthesioneuroblastoma, bladder cancer, testicular cancer, glioblastoma multiforme, cervical cancer; large cell neuroendocrine tumor of lung, non-small cell lung cancers with mixed neuroendocrine features, and Merkel cell carcinoma OR
• DLL3+ (≥1% by IHC) Note: If patients are DLL3 negative per IHC but have a DLL3 prevalant tumor type, they will be allowed to enroll on the study.

Inclusion criteria as written on the registry, trimmed. The full list, with exclusions, is on the live record.