Phase II study of pembrolizumab-based therapy in previously treated extrapulmonary poorly differentiated neuroendocrine carcinomas: Results of Part B (pembrolizumab + chemotherapy)

Autor: Lawrence Fong, Jennifer A. Chan, Delaire Fattah, Nitya Raj, Rahul Aggarwal, Kimberly Perez, Thomas A. Hope, Li Zhang, Jennifer A. Grabowsky, April DeMore, Diane Lauren Reidy, Pamela N. Munster, Kanti Pallav Kolli, Emily K. Bergsland, Mallika Sachdev Dhawan, Susan Calabrese, Sofia Von Fedak
Rok vydání: 2021
Předmět:
Zdroj: Journal of Clinical Oncology. 39:4148-4148
ISSN: 1527-7755
0732-183X
Popis: 4148 Background: The efficacy of immune checkpoint inhibitor (CPI) therapy has not been established in extrapulmonary poorly differentiated neuroendocrine carcinomas (EP-PDNECs). In small cell lung cancer, CPI therapy is approved for use in the first-line and salvage settings. We investigated the efficacy and safety of pembrolizumab (PEM)-based therapy in biomarker-unselected patients (pts) with EP-PDNECs. PEM alone (Part A, N=14) was inactive (ASCO GI 2019; Abstr#363). We now report the results of Part B (PEM plus chemotherapy). Methods: We conducted an open label, multicenter, phase 2 study of PEM-based therapy in pts with EP-PDNECs, excluding Merkel cell carcinoma and well differentiated grade 3 neuroendocrine tumors (NET), with disease progression on first-line systemic therapy. In Part B of this trial, patients were treated with PEM 200 mg IV every 3 week cycle plus dealers’ choice chemotherapy (chemo): weekly irinotecan (IRI, 125 mg/m2 day 1,8 of every 21 day cycle) or weekly paclitaxel (PAC, 80 mg/m2). After PEM/IRI safety lead-in (N=6), 16 additional pts (total N=22) were enrolled. This was based on a primary endpoint of objective response rate (ORR) by RECIST 1.1 and a plan to test Ha ORR 31% vs H0 ORR 10% with 80% power at a type I error rate of 0.05. Secondary endpoints include safety, overall survival (OS), and progression-free survival (PFS). Serial blood samples and baseline tumor biopsies were required in all pts. Results: Preliminary data from Part B are available. Of 22 pts enrolled, male/female 15/7; median age 57 years (range 34-75); ECOG PS 0/1: 10/12; 6 large cell, 8 small cell, 8 NOS. Primary sites of disease: GI 73%, GYN 5%, unknown 23%. Ki67 index (available for 18 pts) median 68% (range 30 to >95%). Chemo choice: 17 IRI (77%) and 5 PAC (23%). PEM/IRI was safe based on lead-in. Median number of cycles of therapy administered was 3 (range 0-13). Treatment-related Gr 3 or 4 AE occurred in 7 (32%) of 22 pts overall: 4 (18%) had at least one Gr 3 AE attributed to PEM (1 pt each with pain, ALT increase, or nausea; 2 with fatigue); 7 (32%) had at least one Gr 3/4 AE attributed to chemo (2 with fatigue, 2 with neutropenia; 1 each with pain, ALT increase, hyponatremia, diarrhea, nausea, and/or acute kidney injury). No grade 5 AE. ORR was 9%: PR in 2 pts (9%), SD 3 pts (14%), PD 13 pts (60%); 4 pts (18%) unevaluable (off study before first scheduled scan). Median PFS 2 mo. At last follow-up, 5 pts (23%) were alive with 1 pt still on treatment. Median OS 4 mo. Of 21 pts off treatment, 76% off for PD, 10% off for AE, 14% off for withdrawal of consent/other therapy. Conclusions: PEM + chemotherapy was not effective in this pretreated, biomarker-unselected population of EP-PDNECs arising in different organs. Biomarker studies are planned (Parts A/B). Clinical trial information: NCT03136055.
Databáze: OpenAIRE