## Facts

- Two pharmaceutical companies competed in the market for once-daily sustained-release diltiazem products: Cardizem CD (Marion Merrell Dow, Inc. (MMD)) and Dilacor XR (Rhone-Poulenc Rorer Pharmaceuticals, Inc. (RPR)).
- RPR sued MMD under § 43(a) of the Lanham Act for false advertising in comparative promotional materials; MMD counterclaimed under the same provision.
- A key dispute involved RPR’s advertising and disclosures about a “food effect” associated with Dilacor XR (the impact of taking the drug with food on pharmacokinetics and potential adverse consequences).
- Both parties made comparative advertising claims, including claims framed as superiority supported by scientific testing.
- After a bench trial, the district court found both parties liable for false advertising, denied damages to RPR, and ordered corrective advertising by RPR, including a requirement that RPR “advise the marketplace” of the product’s “food effect.”
- RPR appealed, principally challenging the denial of damages and the corrective-advertising injunction (especially the “food effect” requirement).

## Issues

1. Whether the district court’s injunction requiring RPR to “advise the marketplace” of “the food effect” satisfied Federal Rule of Civil Procedure 65(d)’s specificity requirement.
2. Whether the evidence supported the district court’s Lanham Act § 43(a) false-advertising findings, including standards for claims asserting scientific test support.
3. Whether the district court abused its discretion by denying RPR monetary relief despite finding MMD liable for false advertising.

## Decision

- The court of appeals affirmed the district court’s findings that both RPR and MMD violated Lanham Act § 43(a) through false or misleading advertising.
- The court affirmed the denial of damages to RPR.
- The court vacated the portion of the decree requiring RPR to “advise the marketplace” of “the food effect” because it was not sufficiently specific under Rule 65(d).
- The court otherwise affirmed and remanded only as needed to address the defective portion of the injunction.

## Legal Principles

- Lanham Act § 43(a) distinguishes between (a) general superiority claims and (b) claims asserting that scientific testing proves superiority:
  - For general superiority claims, the challenger must prove the superiority statement is false.
  - For “tests prove” or similar claims, the challenger may prevail by showing the cited tests are not sufficiently reliable to support the advertised conclusion with reasonable certainty.
- Monetary relief under Lanham Act § 43(a) is discretionary; liability does not require an award of damages absent an adequate showing warranting such relief.
- An injunction must comply with Rule 65(d) by stating required or prohibited acts with reasonable detail; vague commands (e.g., requiring disclosure of a general scientific concept without specifying what must be said) are unenforceable.

## Conclusion

The court upheld mutual Lanham Act false-advertising liability and the denial of damages, but vacated the corrective-advertising requirement to publicize the product’s “food effect” because the injunction failed to specify, with the detail Rule 65(d) requires, what RPR must communicate and how.


Rhone-Poulenc Rorer Pharms., Inc. v. Marion Merrell Dow, Inc., 93 F.3d 511 (8th Cir. 1996)