# Presentation: 699822

## Effects of DTC Advertising of Prescription Drugs on the Treatment of Depression

- Julie Donohue
- September 22, 2003
- FDA Hearing on DTC Promotion

## What we know about DTCA

- Surveys indicate high awareness of DTCA and significant response
- Millions talk to their doctor, ask for a rx, and receive the brand requested or a competing brand
- Economic studies suggest that DTCA
- Increases sales at the therapeutic class level
- Has little to no impact on product market share

## What we don’t know about DTCA

- Its impact on public health
- Expanded treatment for under-diagnosed conditions?
- Appropriateness of new prescriptions?
- Adherence to treatment for chronic conditions?

## Research Questions

- Case study: _antidepressants_
- Does DTCA affect whether someone with depression
- Initiates medication treatment?
- Stays on medication for the appropriate duration?
- Does DTCA affect choice of antidepressant?

## Antidepressant DTCA spending 1997-2000

- Notes: Data from CMR, Zoloft and Celexa had zero DTCA spending during period

## Data Sources

- DTCA data from Competitive Media Reporting
- Detailing data from Scott-Levin
- Free samples data from IMS Health
- Individual-level claims data from MarketScan, Medstat GroupTM

## Initiation of Antidepressant Medication Treatment

| DTCA spending (last 6 months) | % point |
| --- | --- |
|     $2.6 to $11.2 million | 4.0 ** |
|     $11.2 to $18.5 million | 3.0 ** |
|     Over $18.5 million | 5.0 ** |
| Free Samples (last 6 months) |  |
|     94 to 99 million units | 0.3 |
|     99 to 104 million units | 0.3 |
|     Over 104 million units  | 0.5 |

- ** Statistically significant at p<0.01 level compared to lowest quartile (less than $2.6 million)

## DTCA and Duration of Antidepressant Treatment

| Own DTCA spending (last 6 mts) | % point |
| --- | --- |
|    $78,300 to $3.4 million  | 0.0 |
|    $3.4 to $20.2 million | 0.0 |
|    over $20.2 million | 0.3 |
| Others’ DTCA spending (last 6 mts) |  |
|    $271,000 to $7.3 million | 0.0 |
|    $7.3 to $21.8 million | 0.0 |
|    over $21.8 million | 0.5 * |

- * Statistically significant at p<0.05 level compared to lowest quartile (less than $271,000)

## Pharmaceutical Promotion and Choice of Antidepressant

- DTCA had no significant effect on antidepressant choice
- Exception: DTCA had small effect on drug choice for individuals with anxiety disorders
- Detailing had a large positive effect on drug choice
- Drugs with highest detailing spending were twice as likely to be chosen compared to low detailing spenders

## Summary

- DTCA and depression
- Increases number receiving drug treatment
- Has small effect on treatment duration
- Detailing and depression
- Free samples do not increase use of drugs
- Detailing does not increase duration of treatment
- Antidepressant choice driven more by detailing than by DTCA, effect differs by diagnosis

## Implications for public health

- DTCA expands treatment for some conditions
- Questions remain about whether this represents overuse or appropriate use
- DTCA does little to improve adherence for chronic conditions

## Contact Information

- Julie Donohue
- Department of Ambulatory Care and Prevention, Harvard Medical School
- Donohue@hcp.med.harvard.edu
- (617) 509-9202