| Literature DB >> 33244149 |
Elan A Cohen1, Howard H Hassman1, Larry Ereshefsky1,2, David P Walling2, Vera M Grindell2, Richard S E Keefe3,4, Katarzyna Wyka5, William P Horan6,7.
Abstract
The remarkably high and growing placebo response rates in clinical trials for CNS indications, such as depression and schizophrenia, constitute a major challenge for the drug development enterprise. Despite extensive literature on participant expectancies and other potent psychosocial factors that perpetuate placebo response, no empirically validated participant-focused strategies to mitigate this phenomenon have been available. This study evaluated the efficacy of the Placebo-Control Reminder Script (PCRS), a brief interactive procedure that educates participants about factors known to cause placebo response, which was administered prior to the primary outcome assessments to subjects with major depressive or psychotic disorders who had at least moderate depression. Participants were informed they would participate in a 2-week randomized clinical trial with a 50% chance of receiving either an experimental antidepressant medication or placebo. In actuality, all participants received placebo. Participants randomly assigned to receive the PCRS (n = 70) reported significantly smaller reductions (i.e., less placebo response) in depression than those who did not receive the PCRS (n = 67). The magnitude of this effect was medium (Cohen's d = 0.40) and was not significantly impacted by diagnostic status. The number of adverse events (i.e., nocebo effect) was also lower in the PCRS group, particularly in the first week of the study. These findings suggest that briefly educating participants about placebo response factors can help mitigate the large placebo response rates that are increasingly seen in failed CNS drug development programs.Entities:
Year: 2020 PMID: 33244149 PMCID: PMC8026614 DOI: 10.1038/s41386-020-00911-5
Source DB: PubMed Journal: Neuropsychopharmacology ISSN: 0893-133X Impact factor: 7.853
Fig. 1CONSORT flow diagram.
Baseline demographic data, clinical characteristics, and BDI-II scores.
| PCRS group | Non-intervention group | Statistic | |
|---|---|---|---|
| Age (years) | 46.43 (SD = 12.53) | 46.48 (SD = 13.58) | |
| Sex (% male) | 55.7% | 49.3% | |
| Race | |||
| White | 24.3% | 31.3% | |
| African American | 62.9% | 58.2% | |
| Other | 11.7% | 10.4% | |
| Education | |||
| ≤secondary education | 80% | 83.% | |
| >secondary education | 20% | 16.7% | |
| Site | |||
| East cost | 37.7% | 38.8% | |
| West coast | 64.3% | 61.2% | |
| Diagnosis | |||
| Major Depressive Disorder | 61.4% | 62.7% | |
| Schizophrenia | 38.6% | 37.3% | |
| Currently on psychiatric medication | 68.6% | 64.2% | |
| Previous trial participation | 42.9% | 49.3% | |
| Currently in psychotherapy | 27.1% | 19.4% | |
| Body Mass Index | 31.51 (SD = 7.23) | 31.88 (SD = 8.19) | |
| Baseline BDI-II | 30.24 (SD = 8.52) | 28.60 (SD = 6.84) |
BDI-II Beck Depression Inventory-II, PCRS Placebo Control Reminder Scale.
Fig. 2Mean BDI-II scores across visits.
The overall linear decrease was significantly smaller in the PCRS group than the NG. BDI Beck Depression Inventory, PCRS Placebo Control Reminder Script, NG Non-intervention Group. Note: Error bars reflect standard errors.
Fig. 3Adverse events reported at Visit 2 and at Visit 3.
The percentage of reported adverse events was significantly lower in the PCRS group than the NG at Visit 2. The percentage of reported adverse events did not significantly differ between groups at Visit 3. PCRS Placebo Control Reminder Script, NG Non-intervention Group.
Fig. 4Subjective beliefs about performance.
Compared to the NG, a significantly larger proportion of the PCRS group reported staying the same and a significantly smaller proportion of the PCRS group reported getting better. PCRS Placebo Control Reminder Script, NG Non-intervention Group.