Source of funding, conflict of interest (COI), and the interpretation of cancer clinical trials

Abstract

6530 Background: Concern exists that industry sponsorship and financial relationships between investigators and drug companies may bias clinical cancer research. Our objective was to determine whether funding or authors' COI are associated with interpreting cancer clinical trials in more positive light. Methods: We reviewed phase II and randomized clinical trials (RCT) of anticancer and supportive care drugs published in 5 clinical cancer journals in a one-year period. We collected information on study design, source of funding, COI disclosure and results of primary endpoints (EP). Each concluding statement in the articles′s abstracts were independently rated by two reviewers (blinded to other study information) with respect to level of enthusiasm for the experimental agent using a 5-point scale ( Table 1 ). Summary statistics and logistic regression were used to describe the results. Results: 213 articles met inclusion criteria: 124 phase II and 89 RCT. Approximately 40% were funded by industry, at least one COI was declared in 35% of articles. Among 130/213 (61%) articles with clearly positive conclusions, the proportion of articles with highly positive conclusions was 61% in articles that declared COI vs. 40% in articles with no COI (p=0.017, CMH, adjusted for study result). In a stepwise logistic regression with journal, funding, study type, study result, and COI only COI remained significant (OR=2.4, 95%CI 1.2–5.0, P=0.017). While all articles with a negative conclusion had a negative primary EP, 21 articles with clearly positive conclusions had a negative primary EP. The most common reasons for such finding were: positive secondary EP (6 studies), experimental agent had better toxicity profile (5), non-statistically significant difference in favour of experimental agent (4). Conclusion: COI is associated with highly positive conclusions that use superlatives to promote the experimental arm No significant financial relationships to disclose. [Table: see text]