eLife revisits a 2013 research paper by Ivana Bozic, Johannes Reiter, Benjamin Allen, and colleagues that suggests combination therapy, with two (or more) drugs administered simultaneously, lowers the likelihood of tumors developing resistance and offers a higher probability of cancer remission:
Ivana Bozic, Johannes Reiter, Benjamin Allen and co-workers now present a mathematical model designed to predict the effects of combination targeted therapies on tumors, based on the data obtained from 20 melanoma (skin cancer) patients. Their model revealed that if even 1 of the 6.6 billion base pairs of DNA present in a human cell has undergone a mutation that confers resistance to each of two drugs, treatment with those drugs will not lead to sustained improvement for the majority of patients. This confirms the need to develop drugs that target distinct pathways.
The model also reveals that combination therapy with two drugs given simultaneously is far more effective than sequential therapy where the drugs are used one after the other. Indeed, the model of Bozic, Reiter, Allen and co-workers indicates that sequential treatment offers no chance of a cure, even when there are no cross-resistance mutations present, whereas combination therapy offers some hope of a cure, even in the presence of cross-resistance mutations.
Click here for the full eLife digest.