Question

Explain why combination therapy (e.g. 3 drug cocktail for HIV infections) can (1) better attack a specific pathogen than a single drug, and (2) greatly suppresses the rate at which pathogens (especially bacteria and viruses) evolve to be resistant.

Answer 1

Ans. Combination therapy is beneficial for treatment of various diseases.

One major benefit of combination therapies is that they reduce development of drug resistance since a pathogen or tumor is less likely to have resistance to multiple drugs simultaneously.

It is used against various diseases namely tuberculosis, leprosy, cancer, malaria, and HIV/AIDS.

1. It's better attack - different drugs displaying different pharmacodynamics and/or pharmacokinetics could target subpopulations of mycobacteria independently on metabolic stage or location within the organism.

Ex. increased HAART coverage in HIV treatment reduced community viral load, and decreased number of new HIV cases.

Ex ii In cancer -  chemotherapy drugs affect cancer cells at different points in the cell cycle, using a combination of drugs increases the chance that all of the cancer cells will be eliminated.

2. Reduces resistance in pathogen as combined drugs have different molecular structure and action sites hence it all function at different levels and different point of time. So to analyse and develop resistance to evolve strain to survive becomes tedious for microorganism.