Combination therapy or polytherapy is therapy that uses more than one

medication A medication (also called medicament, medicine, pharmaceutical drug, medicinal drug or simply drug) is a drug used to medical diagnosis, diagnose, cure, treat, or preventive medicine, prevent disease. Drug therapy (pharmacotherapy) is an imp ...

or modality. Typically, the term refers to using multiple therapies to treat a ''single'' disease, and often all the therapies are pharmaceutical (although it can also involve non-medical therapy, such as the combination of medications and

talk therapy Talk may refer to: Communication * Communication, the encoding and decoding of exchanged messages between people * Conversation, interactive communication between two or more people * Lecture, an oral presentation intended to inform or instruct ...

to treat depression). 'Pharmaceutical' combination therapy may be achieved by prescribing/administering separate drugs, or, where available,

dosage form Dosage forms (also called unit doses) are pharmaceutical drug products in the form in which they are marketed for use, with a specific mixture of active ingredients and inactive components (excipients), in a particular configuration (such as a cap ...

s that contain more than one

active ingredient An active ingredient is any ingredient that provides biologically active or other direct effect in the diagnosis, cure, mitigation, treatment, or prevention of disease or to affect the structure or any function of the body of humans or animals. Th ...

(such as fixed-dose combinations).

Polypharmacy Polypharmacy (polypragmasia) is the simultaneous use of multiple medicines by a patient for their conditions. Most commonly it is defined as regularly taking five or more medicines but definitions vary in where they draw the line for the minimum ...

is a related term, referring to the use of multiple medications (without regard to whether they are for the same or separate conditions/diseases). Sometimes "polymedicine" is used to refer to pharmaceutical combination therapy. Most of these kinds of terms lack a universally consistent definition, so caution and clarification are often advisable.

Uses

Conditions treated with combination therapy include tuberculosis,

leprosy Leprosy, also known as Hansen's disease (HD), is a long-term infection by the bacteria '' Mycobacterium leprae'' or '' Mycobacterium lepromatosis''. Infection can lead to damage of the nerves, respiratory tract, skin, and eyes. This nerve dam ...

, cancer, malaria, and

HIV The human immunodeficiency viruses (HIV) are two species of ''Lentivirus'' (a subgroup of retrovirus) that infect humans. Over time, they cause acquired immunodeficiency syndrome (AIDS), a condition in which progressive failure of the immune ...

AIDS Human immunodeficiency virus infection and acquired immunodeficiency syndrome (HIV/AIDS) is a spectrum of conditions caused by infection with the human immunodeficiency virus (HIV), a retrovirus. Following initial infection an individual ma ...

. One major benefit of combination therapies is that they reduce development of

drug resistance Drug resistance is the reduction in effectiveness of a medication such as an antimicrobial or an antineoplastic in treating a disease or condition. The term is used in the context of resistance that pathogens or cancers have "acquired", that is ...

since a pathogen or tumor is less likely to have resistance to multiple drugs simultaneously.

Artemisinin Artemisinin () and its semisynthetic derivatives are a group of drugs used in the treatment of malaria due to '' Plasmodium falciparum''. It was discovered in 1972 by Tu Youyou, who shared the 2015 Nobel Prize in Physiology or Medicine for h ...

-based monotherapies for malaria are explicitly discouraged to avoid the problem of developing resistance to the newer treatment. Combination therapy may seem costlier than monotherapy in the short term, but when it is used appropriately, it causes significant savings: lower treatment failure rate, lower case-fatality ratios, fewer side-effects than monotherapy, slower development of resistance, and thus less money needed for the development of new drugs.

In oncology

Combination therapy has gained momentum in oncology in recent years, with various studies demonstrating higher response rates with combinations of drugs compared to monotherapies, and the FDA recently approving therapeutic combination regimens that demonstrated superior safety and efficacy to monotherapies. In a recent study about solid cancers,

Martin Nowak Martin Andreas Nowak (born April 7, 1965) is an Austrian-born professor of mathematical biology, at Harvard University since 2003. He is one of the leading researchers in the field that studies the role of cooperation in evolution. Nowak has held ...

Bert Vogelstein Bert Vogelstein (born 1949) is director of the Ludwig Center, Clayton Professor of Oncology and Pathology and a Howard Hughes Medical Institute investigator at The Johns Hopkins Medical School and Sidney Kimmel Comprehensive Cancer Center. A pio ...

, and colleagues showed that in most clinical cases, combination therapies are needed to avoid the evolution of resistance to targeted drugs. Furthermore, they find that the simultaneous administration of multiple targeted drugs minimizes the chance of relapse when no single mutation confers cross-resistance to both drugs. Various systems biology methods must be used to discover combination therapies to overcome drug resistance in select cancer types. Recent

precision medicine Precision, precise or precisely may refer to: Science, and technology, and mathematics Mathematics and computing (general) * Accuracy and precision, measurement deviation from true value and its scatter * Significant figures, the number of digit ...

approaches have focused on targeting multiple biomarkers found in individual tumors by using combinations of drugs. However, with 300 FDA-approved cancer drugs on the market, there almost 45,000 possible two-drug combinations and almost 4.5 million three-drug combinations for to choose from. That level of complexity is one of the primary impediments to the growth of combination therapy in oncology. T has recently highlighted combination therapy as a top research priority in oncology.

Bacterial infections

Combination therapy with two or more antibiotics are often used in an effort to treat multi-drug resistant Gram-negative bacteria.

Contrast to monotherapy

Monotherapy, or the use of a single therapy, can be applied to any therapeutic approach, but it is most commonly used to describe the use of a single

. Normally, monotherapy is selected because a single medication is adequate to treat the medical condition. However, monotherapies may also be used because of unwanted side effects or dangerous drug interactions.

References

External links