OBJECTIVES: Manufacturers may challenge conclusions of draft economic opinions through written observations or hearings with the CEESP. Our aim was to review and analyze the outcomes of recent contradictory phases in the context of CEESP economic appraisals.

METHODS: We reviewed all CEESP economic opinions published since January 2022. Appraisals that involved contradictory phases were identified, and their transcripts were analyzed to assess the impact on the final economic opinions, specifically focusing on the number of reservations and the characterization of major uncertainty.

RESULTS: A total of 51 economic opinions were reviewed, of which 21 (41%) included contradictory phases. Contradictory phases were solicited in 53% of opinions with major reservations, compared to 34% of opinions without major reservations. Moreover, 70% of opinions concluding with major global uncertainty involved contradictory phases, compared to 34% of those without such characterization. Throughout the studied period, no contradictory phase led to the requalification of any major reservation or the removal of major global uncertainty. However, six exchanges (29%) resulted in the removal of 10 important methodological reservations, and one (5%) led to the addition of an important reservation due to the inclusion of an additional analysis requested by the manufacturer. Opinions that included a requalification had, on average, a higher number of important reservations in the initial opinion compared to other opinions. In cases of requalification, manufacturers frequently highlighted the minimal impact of the methodological choice or parameter uncertainty on results, using previously presented sensitivity analyses to argue for the requalification.

CONCLUSIONS: Although contradictory phases are often driven by major methodological reservations or characterized major uncertainty, manufacturer arguments did not lead to the requalification of these aspects. The CEESP reconsidered the level of some important reservations, indicating a selective impact of contradictory phases.