Real-World Incidence of Febrile Neutropenia among Patients Treated with Single-Agent Amrubicin: Necessity of the Primary Prophylactic Administration of Granulocyte Colony-Stimulating Factor

Recent Advances in the Clinical Translation of Small-Cell Lung Cancer Therapeutics

Small-cell lung cancer (SCLC) is a recalcitrant form of cancer, representing 15% of lung cancer cases globally. SCLC is classified within the range of neuroendocrine pulmonary neoplasms, exhibiting shared morphologic, ultrastructural, immunohistochemical, and molecular genomic features. It is marked by rapid proliferation, a propensity for early metastasis, and an overall poor prognosis. The current conventional therapies involve platinum-etoposide-based chemotherapy in combination with immunotherapy. Nonetheless, the rapid emergence of therapeutic resistance continues to pose substantial difficulties. The genomic profiling of SCLC uncovers significant chromosomal rearrangements along with a considerable mutation burden, typically involving the functional inactivation of the tumor suppressor genes TP53 and RB1. Identifying biomarkers and evaluating new treatments is crucial for enhancing outcomes in patients with SCLC. Targeted therapies such as topoisomerase inhibitors, DLL3 inhibitors, HDAC inhibitors, PARP inhibitors, Chk1 inhibitors, etc., have introduced new therapeutic options for future applications. In this current review, we will attempt to outline the key molecular pathways that play a role in the development and progression of SCLC, together with a comprehensive overview of the most recent advancements in the development of novel targeted treatment strategies, as well as some ongoing clinical trials against SCLC, with the goal of improving patient outcomes.

Safety and efficacy of amrubicin with primary prophylactic pegfilgrastim as second-line chemotherapy in patients with small cell lung cancer

BACKGROUND

Amrubicin (AMR) regimens have shown efficacy as second-line treatment in patients with small cell lung cancer (SCLC); however, adverse events such as febrile neutropenia (FN) sometimes preclude their use. Further, the safety and efficacy of AMR with primary prophylactic pegfilgrastim (P-PEG) have not been sufficiently evaluated. In this study, we evaluated the safety and efficacy of AMR with or without P-PEG as second-line chemotherapy for SCLC.

METHODS

We retrospectively reviewed patients with SCLC who received AMR as second-line chemotherapy at Shizuoka Cancer Center, between December 2014 and November 2021. Based on presence/absence of P-PEG in their regimen, patients (n = 60) were divided into P-PEG (n = 21) and non-P-PEG groups, and their clinical outcomes were evaluated.

RESULTS

Median of AMR treatment cycles was five (range: 1-39 cycles) in P-PEG group and four (range: 1-15 cycles) in non-P-PEG group. The incidence of FN (4.8% vs. 30.8%; p = 0.02) and AMR dose reduction because of adverse events (4.8% vs. 25.6%; p = 0.08) were lower in the P-PEG group than in the non-P-PEG group. The objective response rates were 52.4% and 30.8%, and median progression-free and overall survival were 4.7 and 3.0 months, and 9.6 and 6.8 months, in the P-PEG and non-P-PEG groups, respectively.

CONCLUSIONS

AMR with P-PEG as second-line chemotherapy for SCLC reduced the incidence of FN at a maintained AMR dose intensity and was associated with favorable tumor responses and survival outcomes. P-PEG should be considered for patients treated with AMR for SCLC including refractory relapsed SCLC.

Phase I study of amrubicin plus cisplatin and concurrent accelerated hyperfractionated thoracic radiotherapy for limited-disease small cell lung cancer: protocol of ACIST study

Background

Etoposide plus cisplatin (EP) combined with concurrent accelerated hyperfractionated thoracic radiotherapy (AHTRT) is the standard treatment strategy for unresectable limited‐disease (LD) small cell lung cancer (SCLC), which has remained unchanged for over two decades. Based on a previous study that confirmed the non‐inferiority of amrubicin (AMR) plus cisplatin (AP) when compared with EP for extensive‐disease (ED) SCLC, we have previously conducted a phase I study assessing AP with concurrent TRT (2 Gy/time, once daily, 50 Gy in total) for LD‐SCLC therapy. Our findings revealed that AP with concurrent TRT could prolong overall survival to 39.5 months with manageable toxicities. Therefore, we plan to conduct a phase I study to investigate and determine the effect of AP combined with AHTRT, recommended dose (RD), maximum tolerated dose (MTD), and dose‐limiting toxicity (DLT) of AP in patients with LD‐SCLC.

Methods

Treatment‐naive patients with LD‐SCLC, age between 20 and 75 years, who had a performance status of 0 or 1 and adequate organ functions will be enrolled. For chemotherapy, cisplatin 60 mg/m²/day (day 1) and AMR (day 1 to 3) will be administered with AHTRT (1.5 Gy/time, twice daily, 45 Gy in total). The initial AMR dose is set to 25 mg/m²/day. RD and MTD will be determined by evaluating toxicities.

Discussion

Based on our previous study, the initial dose of AMR 25 mg/m² is expected to be tolerated and acceptable. Here, we aim to determine whether treatment with AP and concurrent AHTRT would be an optimal choice with manageable toxicities for LD‐SCLC.