Business Source Complete Has industry, marketing and advertising information, news, and more. Contains scholarly journals, plus trade publications, newspapers and magazines.
U.S. Pharmacist: a free online journal for Pharmacists. May be useful for HoQ or Competetive Analysis
Also use PubMed and SciFinder Scholar to find articles and sort to get the oldest articles
Also try Micromedex and find comparitive efficacy
Medical Letter also may have useful lengthy treatment guidelines articles.