Abstract 880P
Background
Concurrent radiotherapy (RT) plus cisplatin is the preferred systemic treatment for newly diagnosed pts with LA HNSCC ineligible for surgery. As clinical trials explore novel treatments and alternative chemoradiotherapy (CRT) options for this indication, the aim of this SLR was to summarize the trials in this population in terms of study design, trial endpoints and pt characteristics.
Methods
Embase, MEDLINE, CENTRAL, and conference proceedings were searched on May 20, 2020. All randomized controlled trials with systemic and RT interventions reporting treatment outcomes including overall survival (OS), progression- or event-free survival (PFS or EFS), and rates of recurrence and disease control were of interest. Studies of surgical interventions and studies conducted in pts eligible for surgery were excluded.
Results
The SLR identified 143 trials, comparing different CRT regimens (n=50 trials), variations of the same CRT regimens (n=20), CRT versus RT regimens (n=52), and variations of RT regimens (n=21). In the 50 studies comparing different CRT regimens, platinum (n=31), platinum + 5-FU (n=15), and platinum + taxane + 5-FU (n=11) were the most common. Trials were heterogenous in terms of sample size (range: 22 - 1,113 pts), median follow-up duration (range: 9 months - 13.6 years) prognostic baseline characteristics (tumor stage and location, smoker status, and human papillomavirus infection status), and response evaluation criteria (RECIST, RECIST v1.1, WHO, modified WHO) while they were similar in age, gender and race. Most trials reported OS and PFS, but EFS was rarely reported. Definitions of PFS/EFS, where provided, were not consistent: death due to any cause and disease progression were generally considered PFS events, but trials often also considered other definitions, such as treatment discontinuation and second primary malignancy as events.
Conclusions
There is considerable heterogeneity among the clinical studies in the target population. Any form of indirect treatment comparison should consider the underlying differences in baseline characteristics and outcome definitions.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Merck & Co., Inc.
Funding
Merck & Co., Inc.
Disclosure
K. Ramakrishnan: Financial Interests, Institutional, Full or part-time Employment: Merck & Co., Inc.; Financial Interests, Institutional, Stocks/Shares: Merck & Co., Inc. P. Wu: Financial Interests, Institutional, Funding, Employee of PRECISIONheor, which received funding from Merck & Co, Inc. to conduct the study.: PRECISIONheor. C.M. Black: Financial Interests, Personal and Institutional, Full or part-time Employment: Merck & Co Inc.; Financial Interests, Personal, Stocks/Shares: Merck & Co Inc. S. Keeping: Financial Interests, Institutional, Funding, Employee of PRECISIONheor, which received funding from Merck & Co, Inc. to conduct the study.: PRECISIONheor. N. Upadhyay: Financial Interests, Institutional, Full or part-time Employment: Merck & Co., Inc. A. Mojebi: Financial Interests, Institutional, Funding, Employee of PRECISIONheor, which received funding from Merck & Co, Inc. to conduct the study.: PRECISIONheor.