The Days of ASCO - Biosimilars

Biologics are products that are made from living things - animals, humans, microorganisms. They are manufactured using bio-technology or other methods. They are usually large molecules, organic, complex mixtures and difficult to identify. Conventional drugs are chemical and their structures can easily be identified. Some examples of biologics are: Cytokines - interferon, Monoclonal antibodies - herceptin and vaccines. Biosimilars are biologics that are approved/ licensed by the FDA because they are highly similar to an already FDA approved drug. The FDA approved drug is called the reference product.

In the morning of Tuesday June 7,  I attended the ASCO session Biosimilars: Hear and Now
Speakers: Lemery, Weise, Esteva
 

Biologics have inherent molecular differences. They are not identical so they are not generics.Biotech/ drug companies with a biosimilar product must apply to the FDA for approval.
The general requirements are given below.

 

 Biosimilarity /interchangeability must be based on data from 

• Analytical studies
• Animal studies ( toxicity assessment) 
• clinical studies ( pharmaokinetics and pharmacodynamics

If a product is given a biosimilar designation in the US than the product must be prescribed by the health care provider and should not be substituted ( by the pharmacist) without the intervention of the health care provider.

Biosimilarity is determined using the totality of the evidence. Analytical comparisons are the foundation for determining that the products are highly similar . There is no need to to re-establish safety /effectiveness of the biosimilar product.

Dr Weise provided an overview of biosimilar use in the European Union. The EU has been using a similar process to approve biosimilars for the past 10 years. The example discussed during the session was Filgrastim, biosimilar to Neupogen.

But there are challenges to biosimilars in the US. There is the need to regulate, monitor and track the safety in patients. Will the biosimilar be covered by insurance?  Will providers be willing to prescribe the biosimilar with the limited efficacy and safety data compared to the original biologic.

Dr Esteva raised another question in his presentation. Will patients accept the biosimilar drugs? As patients in the US play a greater role in their care the safety data and efficacy data of the biosimilars must be communicated with patients effectively.   Currently in the US Zarxio, a biosimilar to Neupogen,  has FDA approval. In development by Pfizer and Amgen are biosimilars to Trastuzumab ( Herceptin) .

One benefit of the use of biosimilars is a lower cost( ~30% lower) .

As I listened to this session I kept wondering what I would do if in the future I was offered a biosimilar. As someone who has had issues after being prescribed generic medications I would definitely ask my doctor to see the  clinical studies used in the approval process.

Dee
Every Day is a Blessing!

Additional sources of information: 

FDA http://www.fda.gov/Drugs/DevelopmentApprovalProcess/HowDrugsareDevelopedandApproved/ApprovalApplications/TherapeuticBiologicApplications/Biosimilars/ucm241718.htm

Oncolink-http://www.oncolink.org/treatment/article.cfm?c=16&id=335