Biologics are considered the new miracle drugs. Radical recoveries are giving biologics a much-hyped reputation as miracle drugs. Biologic medicines are now the fastest-growing class of drugs in the pharmaceutical world; Avastin alone garnered nearly $3 billion in sales in 2008. Many patients today survive cancers once considered a death sentence, and those who suffer from autoimmune diseases such as multiple sclerosis or rheumatoid arthritis can regain full use of limbs once racked by crippling pain and immobility.
What makes biologic medicines unique is this: unlike conventional chemical drugs, biologics are produced by being grown inside living organisms, and specifically target human proteins that are involved in disease.
One class of biologics—known as monoclonal antibody biologics—are similar to the antibodies that the human immune system uses to fight off bacteria and viruses, only these antibodies are genetically engineered to target specific cancers.
Avastin is now also widely used to treat lung, breast, colon, and rectal cancers. Other monoclonal antibody biologics are designed to attack certain proteins (or protein receptors) on the surface of cancer cells and stop their growth. Examples of such protein inhibitors include Rituxan, which is used to treat lymphomas, and Herceptin.
Other biologics alter the function of the immune system by either suppressing or enhancing certain responses. In autoimmune diseases such as rheumatoid arthritis and psoriasis, for example, the immune system overproduces a protein that triggers a buildup of white blood cells, which leads to excessive inflammation and joint damage. Enbrel, Humira, Remicade, and other biologics in this class target that protein, called the tumor necrosis factor, and block its action. Tysabri, a biologic used to treat multiple sclerosis and Crohn's disease, blocks the passage of inflammatory cells into the brain and the spinal cord—and, in the case of Crohn's disease, into the intestines.
"These biologic agents provide a degree of selectivity not achievable with conventional chemotherapy drugs," explains oncologist Oliver Press, M.D., Ph.D., of the Fred Hutchinson Cancer Research Center in Seattle. "Many of [the biologics] can produce dramatic antitumor effects without the toxicity that historically has been associated with chemotherapy and radiation."
Biologic treatments date back to 1982, when recombinant insulin was first approved in the United States for the treatment of diabetes. (A hormone originally derived from the pancreas of animals, insulin is today made synthetically from genetically engineered human bacteria.) Since then, more than 300 biologic drugs, most of them developed in the past five years, have flooded the pharmaceutical market. Today they constitute roughly 25 percent of all new drugs approved by the FDA; by 2014, industry insiders predict, more than half of the top 100 drugs will be biologics.
Biologic treatments are very expensive. A push is on to develop generic drugs.
http://www.aarp.org/health/conditions/biologics/
AARP: Biologic Drugs
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