Endpoints in clinical trials: What do patients consider important? A survey of the Ovarian Cancer National Alliance

Abstract

In order to understand the patient's perspective in regards to meaningful surrogate clinical trial endpoints and the impact of treatment-related toxicity, and quality of life, we surveyed women with gynecological cancers to ascertain their preferences. A 28-question anonymous online survey was posted on the OCNA website (www.ovariancancer.org). Survey questions included demographic factors, tumor data, and patients' preference regarding side effects and therapy endpoints. Data was analyzed for frequency and percentage of each response. Student t-test, Fisher's exact test and Wilcoxon rank sums were preformed. There were 1413 survey responses. Participants reported that for a new agent to be meaningful, the minimum extension of progression-free survival (PFS) and overall survival (OS) should be five or more months, 77% and 85% of the time, respectively. Most subjects (55%, n=612) were interested in an agent that would keep tumor growth relatively static without change in OS. Addressing the impact of adverse aspects from a hypothetical new agent as a function of response, there was significant migration (p<0.0001) to acceptance of greater toxicity and cost under the scenario of a 5-6months OS gain, despite three-fold higher neurotoxicity, as compared to a PFS gain of 3-4months/no OS gain without toxicity. Response patterns weren't altered by recurrence status. Herein, we show that magnitude of outcome is a desired effect, even given the prospect of significant toxicity and cost. However, these preferences appear to differ between those with primary and recurrent disease.