What is a Medical Science Liaison (MSL) and what do they do all day?

Updated: 5 days ago

What is a medical science liaison (MSL)?


Being able to define the MSL role is critical for a successful interview. When you get asked this question, use the following answer;


An MSL is a member of the medical affairs team within a pharma company.

An MSL is a non-promotional role. The MSL acts as the bridge between the internal pharma company and the external therapeutic environment. The role of the MSL is to develop collaborative relationships with key opinion leaders in given therapeutic area and utilise these collaborations and insights gained from these KOLs to execute projects that are aligned to the brand strategy.


For example, an MSL working on a product that treats breast cancer will interact with key oncologists specialising in breast cancer and leverage these relationships to achieve some of the key strategic objectives of the brand. Examples of leveraging these relationships include inviting the oncologists to attend advisory boards, or to speak at pharma sponsored education events or to do a clinical trial with the product in question.

What is the difference between an MSL and a sales reps?


There are a few key differences between an MSL and a sales rep.


1. Sales rep is promotional. MSL is non-promotional. Sales reps have metrics with respect to sales, MSL may have metrics but they are not sales related. MSL metrics tend to be qualitative in nature as opposed to quantitative. An example of qualitative MSL metrics may be execution of specific medical projects or development of KOL relationships.

2. The objective of the sales rep is to get the doctor to prescribe the product. The objective of the MSL will be related to the overall brand strategy, but it is not to sell.

3. Sales reps will use promotional material and key selling messages in discussions with doctors and MSLs will use clinical papers and try and gain as many insights as possible from the doctor.

That being said, MSLs and sales reps often work closely together. Both MSL and sales reps must develop relationships with doctors. So there are some similarities to the roles and a collaborative relationship with sales reps is a mark of a high performing MSL.


Who else does the MSL interact with within the pharmaceutical company?


The MSL will work with other members of the medical affair team for example, medical manager, MSL manager and scientific advisor.


The MSL will also work with members of;


  • Pharmacovigilance team – MSL will report adverse events (AEs) to this team

  • Medical information team – MSL will help with answering medical inquiries from healthcare professionals

  • Regulatory team – MSL will provide scientific expertise to assist with getting a product registered

  • Marketing team – MSL will understand the overall brand strategy and how the medical strategy fits into this

  • Training department – MSL will develop training materials to educate the sales reps

What does an MSL actually do all day?


Activities of an MSL include but are not limited to;


  • Promotional review – this means assessing promotional materials and ensuring they are accurate, balanced and reflect the data

  • Supporting sales reps – answering questions/training sales reps.

  • Seeing KOLs – discussing scientific data

  • Organising travel to see KOLs

  • Preparing for KOL meetings

  • Internal compliance/training – pharmaceutical industry is a highly regulated environment which means lots of internal compliance training

  • Upskilling in the therapeutic environment – using google scholar to read new publications

  • Planning advisory boards

  • Internal meetings with different colleagues

  • Managing investigator-initiated studies

  • Attending conferences


So in summary, the MSL role is quite a varied position and MSLs work with many different departments.


Want more information on becoming a high performing MSL? Sign up to my newsletter to get MSL tips straight to your inbox every week. If you have any questions about anything in this post, drop me an email to info@mslconsultant.com and I'll reply.

Recent Posts

See All