Here is a recommended curriculum on that subject, published by the American Medical Student Association: Evidence and Recommendations for a
Model PharmFree Curriculum
Here is the AMSA's advocacy web site on that subject: http://www.pharmfree.org/
I don't know to what extent they've been successful at introducing any such courses at medical schools.
The topic has been studied (see page 9 of the above document), for example in the following study.
An innovative approach to educating medical students about pharmaceutical promotion.
The authors describe an educational program, in which university pharmacists portrayed pharmaceutical company representatives to model a promotional presentation, that they designed to generate critical thinking among third-year medical students regarding the influence of pharmaceutical representatives on the prescribing practices of physicians. The authors also provide information suggesting that the program increased the uncertainty many students felt about the accuracy and ethics of standard drug "detailing."
If such a study counts as a "course" that shows that there has been at least one such course.
Googling suggests to me that the current formal "state of the art" is (mostly, merely) to ask medical schools to clarify their "conflict of interest" guidelines: http://www.amsascorecard.org/