Abstract 5710
Background
Merkel cell carcinoma (MCC) is a rare, aggressive tumour of the skin associated with high recurrence rates and poor survival. Clinical trials have shown activity of various checkpoint inhibitors targeting programmed death-(ligand)-1 (PD-(L)1). Avelumab is currently the only PD-L1 inhibitor that has been approved in the Netherlands for advanced/metastatic MCC (mMCC). Here, we report the Dutch real-world efficacy data of avelumab in patients with mMCC.
Methods
All mMCC patients from 4 tertiary referral centres in the Netherlands from December 2016 were analysed. Patients were included in this analysis if they had received avelumab for mMCC, regardless of other previous lines of therapy. Patient data were collected retrospectively and followed up prospectively after initiation of data collection. Primary endpoints were response rate (RR) and duration of response (DOR) , secondary endpoints were progression free survival (PFS), overall survival (OS) and toxicity. Toxicity was evaluated according to CTCAE version 5.0.
Results
Forty-six patients received avelumab, of which 37 patients were evaluable for response (9 had not reached response evaluation, 1 died due to comorbidity). In 22 (59.5%) patients avelumab was first-line treatment. Median follow up time was 7.8 (IQR 3.7-10.1) months. RR was 59.5% (n = 22) with 21.6% (n = 8) of patients having a complete radiological response. Median DOR was 6.3 (IQR 3.0-12.5) months and 15 (40.5%) patients had ongoing response at time of data analysis. Median PFS was 12.2 (95% CI 3.3-21.1) months, median OS was not yet reached. In subgroup analysis no differences were found for the presence of visceral metastases at baseline or previous lines of therapy. Five (13.2%) patients experienced grade 3 toxicity, of which 2 (4.3%) patients discontinued avelumab. No grade 4-5 toxicity were seen.
Conclusions
In the Netherlands treatment with avelumab is increasingly used in first- and second-line treatment for mMCC. In this real-world cohort, RR, DOR, PFS and toxicity results were in line with results from clinical trials and show relatively high, durable responses in patients with mMCC, unaffected by the presence of visceral metastases or previous lines of therapy.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
2275 - Activating mutations in AKT1/PIK3CA are associated with poor clinical outcomes in metastatic prostate cancer (mPC)
Presenter: Simon Fu
Session: Poster Display session 3
Resources:
Abstract
1908 - Androgen Receptor (AR) Aberrations in Patients (Pts) With Metastatic Castration-Sensitive Prostate Cancer (mCSPC) Treated With Apalutamide (APA) Plus Androgen Deprivation Therapy (ADT) in TITAN
Presenter: Kim Chi
Session: Poster Display session 3
Resources:
Abstract
4058 - 68Ga-PSMA guided bone biopsies for molecular diagnostics in metastatic castration resistant prostate cancer patients
Presenter: Anouk de Jong
Session: Poster Display session 3
Resources:
Abstract
2226 - Spatial-Temporal Change in Quantitative Total Bone Imaging (QTBI) and Circulating Tumor Cells (CTCs) in Metastatic Castration-Resistant Prostate Cancer (mCRPC) Treated With Enzalutamide (ENZA)
Presenter: Glenn Liu
Session: Poster Display session 3
Resources:
Abstract
5795 - Efficacy of Enzalutamide in Hormone-sensitive Metastatic Prostate Cancer: Clinical Utility of 18F-Choline PET and Whole Body MRI.
Presenter: Susanne Osanto
Session: Poster Display session 3
Resources:
Abstract
899 - Urine extracellular vesicle GATA2 mRNA alone and in a multigene test predicts initial prostate biopsy result
Presenter: Jungreem Woo
Session: Poster Display session 3
Resources:
Abstract
3094 - Circulating tumor cell (CTC) genomic landscape in neuroendocrine prostate cancer (NEPC) by single cell copy number analysis
Presenter: Vincenza Conteduca
Session: Poster Display session 3
Resources:
Abstract
2527 - Circulating Tumor Cells (CTC) count and Prostate-Specific Antigen (PSA) response measures in metastatic Castration-Resistant Prostate Cancer (mCRPC) patients (pts) treated with Docetaxel (Doc)
Presenter: Rebeca Lozano Mejorada
Session: Poster Display session 3
Resources:
Abstract
6106 - Assessing the clinical relevance of drug–drug interactions (DDI) with darolutamide (DARO)
Presenter: Christian Zurth
Session: Poster Display session 3
Resources:
Abstract
2237 - KEYNOTE-921: phase 3 study of pembrolizumab (pembro) plus docetaxel and prednisone for enzalutamide (enza)- or abiraterone (abi)-pretreated patients (pts) with metastatic castration-resistant prostate cancer (mCRPC).
Presenter: Daniel Petrylak
Session: Poster Display session 3
Resources:
Abstract