You don't see too many published articles on this topic. However, if you do a search on PubMed, you'll actually find a German article published in 2000 titled, "[Career opportunities for female and male physicians in the pharmaceutical industry]" - (note: the brackets are there because this is a translated title)
If you're interested in reading the abstract from Med Klin (Munich) then here it is:
INTRODUCTION: Pharmaceutical medicine is not only a mainstay in clinical drug development and marketing of drugs in pharmaceutical industry but also a challenging alternative to the clinic and outpatient practice for physicians. Since most of them have only a vague notion of what a career in this sector of industry involves, this paper attempts to display the scope of opportunities and responsibilities for physicians and to answer some of the most frequently asked questions.So, do you think a lot has changed since 2000? How does this article apply to physicians in the United States?
JOB PROFILES: Areas for physicians are preclinical research, clinical research, drug safety, biometry, scientific relations, marketing and sales departments, working as company physician, training of sales representatives, health policy and project management. Earnings, continued and postgraduate training, job changing as well as possibilities of information on a career in the pharmaceutical industry are described.
CONCLUSION: Despite the wide range of job profiles, a physician is still a physician in the pharmaceutical industry: his or her aim is to help patients and relieve their suffering through ethical and innovative therapeutic research. This aim is achieved through committed involvement in the development and marketing of new, effective and safe drugs.
Med Klin (Munich). 2000 Jun 15;95(6):322-6.
You can review this PubMed abstract here.