New approach to drug delivery

(MAINS GS 3 : Science and Technology: Recent developments and their applications and effects in everyday life) 

Context:

• Recently a research published in the journal Angewandte Chemie shows that researchers from the University of Massachusetts designed a type of  nanoparticle which embodies a new approach to treating diseases like pancreatic cancer that could potentially revolutionise the field. 

Targeted drug delivery:

• The new approach combines concepts of biologics and antibody–drug conjugates to produce protein–antibody conjugates that can be used for targeted drug delivery for example in case of pancreatic cancer. 
• The team has tested the mechanism in cell lines in the lab and now plans to move on to studying it in mouse models. 

The two approaches:

• The new concept, namely, Protein–Antibody Conjugates or PACs, combines two different approaches to drug delivery. 
• One is biologics, where the idea is to target a defective protein in the system by delivering proteins to it. 
• An example of this is the case of insulin treatment where if a person is short of insulin, which is a protein, they are given a shot of this protein which balances the system.

Antibody conjugates

• The other concept is of using antibodies for drug delivery. 
• Antibodies are something the body produces to detect a foreign substance inside the body. 
• Antibodies can be developed to recognise anything that does not belong in our bodies including cancer cells as well. 
• If there is something different on the surface of a cancer cell compared to a healthy cell, an antibody can be designed that selectively goes to the cancer cell.
•  Drug molecules can be attached to the antibody, forming drug–antibody conjugates.
• Researchers developed protein–antibody conjugates or PACs, which have a protein attached to the antibody, and this conjugate can zero in on pancreatic cancer cells.

Undruggable cases:

• 90% of pancreatic cancers  are undruggable as researchers till now do not know how to design drugs that will bind these cancerous cells.
• But with proteins, molecules can be designed that will bind to the target cells.
• In telling analogy, researchers compare the protein–antibody conjugate to an addressed envelope containing the drug. 
• The antibody plays the role of the address and indicates the cell where the drug should precisely be delivered.