The ability to induce remission in rheumatoid arthritis and other forms of arthritis has largely occurred because of the advent of biologic therapies.?This article discusses what biologic medicines are.

Biologics are drugs that are made from living sources (hence the term 揵iologic? such as humans, animals or microorganisms and grown in specially engineered cells.?They differ from conventional medicines which are developed through chemical reactions in the laboratory.

The first biologics were vaccines. 燩robably the earliest credible account of a vaccine was the one produced in the laboratory by Louis Pasteur in 1879.

A few short years later Banting and Best were able to isolate insulin, another biologic used to treat diabetes.

Blood and blood products such as plasma, white cells, and platelets are also considered 揵iologic?treatments.

The biologics that have most recently been created have been derived through sophisticated biotechnological research techniques using genetic material, DNA, and cell fusion techniques.

The biologics of today are called "large molecule" drugs.?They are not only larger in molecule size and number but are also more complex in general compared with conventional drugs ("small molecule" drugs).?Small molecule drugs consist of drugs that contain between 20 to100 atoms. An example would be aspirin which has 21 atoms. These drugs can be taken orally.

Because of their large size, biologics typically are injected subcutaneously or intramuscularly or infused intravenously.

Biologic drugs have revolutionized the treatment of diseases such as rheumatoid arthritis (RA), psoriatic arthritis, ankylosing spondylitis, and systemic lupus erythematosus.

Most of the biologic drugs used for arthritis treatment were first applied in RA and then further research lead to approval for other rheumatic diseases.

Examples of biologic drugs used to treat arthritis include anti-TNF drugs such as etanercept (Enbrel),?adalimumab (Humira), and infliximab (Remicade), anti-IL-1 drugs like anakinra (Kineret), anti B-cell therapies like rituximab (Rituxan), and T-cell co-stimulatory blockers like abatacept (Orencia).

Using both clinical as well as laboratory measurements, physicians have been able to demonstrate remarkable disease response to these new agents. Prior to the use of biologic drugs, it was unusual for rheumatologists to talk about remission. 燦owadays, it is usually possible to achieve remission.

燘iologic drugs do have potential side-effects that limit their effectiveness. 燭he first is increased incidence of infections in patients receiving biologics. 燭he second is drug toxicity.?The last is the development of antibodies to the biologic.

Because there are many patients who fail biologics because of allergic reactions, primary failure (don抰 respond at all), secondary failure (respond initially, but then fail), and drug toxicity, further research is being conducted to develop drugs with other mechanisms of action.