Measuring treatment impact: a review of patient-reported outcomes and other efficacy endpoints in approved product labels

Abstract Context The term “patient-reported outcomes” (PROs) has evolved to include any endpoint derived from patient reports, whether collected in the clinic, in a diary, or by other means, including single-item outcome measures, event logs, symptom reports, formal instruments to measure health-related quality of life (HRQL), health status, adherence, and satisfaction with treatment. This term coincides with the explicit interest from drug development researchers and regulatory authorities in the appropriate utilization and reporting of treatment impact measures. Objective To determine the level and nature of use of PROs compared to other types of effectiveness endpoints in approved product labeling for new drugs recently approved in the United States. Design and sources Review and analysis of effectiveness endpoints as reported in clinical study descriptions in approved product labeling of new molecular entities (NMEs) approved in the United States from 1997 through 2002. Main outcome measures Effectiveness study endpoints reported in approved product labeling that fall into the following categories of measurement: PROs, clinician-reported outcomes (CROs), and laboratory test/device measurement endpoints. Results PROs were reported in 64 (30%) of the 215 product labels reviewed. Clinician-reported outcomes were reported most frequently (62%) followed by laboratory/device endpoints (50%). PROs were the only type of endpoint used in the FDA-approved label for 23 products. Formal multiitem PRO scales were cited 22 times. Use of PROs is most common in antiinflammatory, CNS, gastrointestinal, respiratory, allergic conjunctivitis, and urologic therapy areas. The frequency of reported PRO use over this period did not change. Conclusion PROs, although quite variable as a class of study endpoints, were found to have a significant role in the development and evaluation of new medicines. More formal guidance from the FDA about use of such measures along with continued collaboration by PRO researchers to develop and disseminate standards will enhance the appropriate use of PROs in future drug development and labeling.