More and more, a one-size-fits-all approach to medicine has been shown to simply be ineffective. With resistant strains of disease, genetic differences in patients and the requirement for more effective (yet less damaging) treatment options, modern medicine is beginning to change its approach. With more attention paid towards personalized medicine, attempts at fewer side effects and ongoing research into gene therapy and immunotherapy, we are now seeing a pronounced shift. One method gaining a lot of attention is combination therapy.
What is Combination Therapy?
Combination therapy (or polytherapy) is a broad term for the use of multiple medications or therapies, in order to fight the same condition. While it typically denotes the use of two or more drugs, it can also include immunotherapy, non-medical therapies – including psychological therapy – and other means of therapy or treatment. The practice may not be new but we have seen a very large increase in the number of approved and researched combination therapies, over the past decade. With many doctors, oncologists, and other medical professionals recommending combination therapies for a large number of diseases and conditions, it is important to know how this approach can aid in treatment and recovery.
How is Combination Therapy Beneficial?
Each drug or treatment method approved for use by the FDA must prove to be an effective method of treatment. However, using a monotherapy approach may not always bring about the desired result. With maximum dosages, resistances and other factors impacting treatments, combination therapy may give a measured increase in response rates.
Specific combination therapy measures also go through clinical trials, in order to prove efficacy and maintain levels of safety. This is to make sure that the combined effects are not hazardous, while demonstrating how the two or more treatment methods interact with one another. While one drug may be used to reduce inflammation or slow the movement of disease, another may directly destroy the foreign cells, for example. This is also advantageous when the treatment method for attacking a disease requires harmful levels of toxicity, as smaller dosages can be required in curing a disease or causing remission.
How is Combination Therapy Currently Used?
There are quite a number of actively used combination therapies currently being used in the market, along with many others undergoing clinical trials. The treatment of aggressive diseases often benefits very noticeably from combination therapy, especially when involving the immune system. In fact, one often-cited combination therapy is HAART: Highly Active Antiretroviral Therapy used in the treatment of HIV. With six major types of drugs being used in this combination therapy, each slows or disrupts the replication of HIV cells in different ways. While entry inhibitors disrupt HIV from binding to receptors on the outside of healthy cells, integrase inhibitors block integrase enzymes: an enzyme used by the virus to push genetic information into infected cells (Source: US National Institute of Allergy and Infectious Diseases).
One combination therapy recently approved in the US by the FDA is the combined use of Abraxane (paclitaxel protein-bound particles for injectable suspension, albumin-bound) and gemcitabine (Source: US Food and Drug Administration). Approved for the treatment of metastatic adenocarcinoma of the pancreas, each one of these chemotherapy drugs suits a specific purpose in the combination therapy. While the paclitaxel acts as a microtubule inhibitor – keeping cancer cells from growing and spreading – the gemcitabine replaces segments of cell DNA to force apoptosis (programmed cell death).
At OncoSec, we are conducting a combination study in melanoma with Old Dominion University. Announced in June, the research study will examine a combination therapy approach that uses our proposed ImmunoPulse treatment (currently undergoing clinical trials), along with Anti-CTLA4, Anti-PD1 and Anti-PDL-1 in a melanoma mouse model. This research opportunity will allow us to examine this combined method, to see if response rates increase over the monotherapy approach. For more information on the study of this proposed combination therapy method, please see our press release.
(Title image by Kiran Foster)