Rosacea: An Introduction

Problems with Trials

  • Participants in trials for topical rosacea medications such as Metrogel have invariably suffered from papulopustular rosacea. Despite this, erythematotelangiectatic rosacea, found alone in the earliest stage of rosacea is ignored, despite early rosacea treatment providing the best prognosis.
  • Its arguably easier to gain FDA/TGA approval for a topical rosacea medication tested on pustules and papules (they're easy to count and more responsive than broken capillaries).
  • Topical rosacea medications have been approved for being partially effective on only a subset of advanced rosacea symptoms.
  • Papules and pustules can come and go on their own in 3-12 days without treatment anyway. In a study that lasts several months, a good amount of skin lesion reduction (if not most in some cases) is natural outcome that would have occurred with or without topical rosacea treatment application.
    • The trials are more likely to have measured the ability of conventional topical rosacea treatments to reduce the formation of entirely new skin lesions.
      • Most of the topical rosacea treatment medication trials have (predictably) shown a strong placebo response.
  • Trials have often measured reduction in percentages of papules/pustules rather than giving actual numbers (a 75% reduction in papules sounds more impressive than a reduction of 3 papules from a starting point of four, and prevents effective comparisons from being made between different studies).
  • Papules and pustules have often been counted separately, but they're actually the outward signs of a single inflammatory progress at different stages of resolution. The result is inflated, misleading skin lesion counts (and warped results).
  • The result is an excess of rosacea treatment agents aimed at reducing a limited number of the signs of advanced rosacea, and virtually nothing for early stages characterized by flushing and broken/distended capillaries - a stage of rosacea where effective treatment could greatly enhance prognosis.

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