First Report of Response to Tarlatamab in a Patient With Histologic-Transformed SCLC From ALK-Rearranged NSCLC: Case Report.

Small cell transformation has been described as a resistance mechanism to targeted therapy treated in patients with EGFR-mutated NSCLC and less often reported with those with other actionable oncogenic alterations, including ALK-rearranged NSCLC. Given lack of standard-of-care treatments for patients with actionable oncogenic alteration NSCLC transformed to SCLC, this remains a challenge and unmet need for treating these patients. Here, we present a case of a patient with ALK-rearranged NSCLC with transformation to SCLC, who has progressed on several lines of therapies and successfully treated with tarlatamab to elicit and maintain clinical benefit, including intracranial response.