|
|
|
FDA Home | Search FDA Site
| A-Z Index | Contact
FDA
FDA Consumer magazine
May-June 2003
Table of Contents
Topics in This Issue:
Encouraging physicians to prescribe antibiotics only when clinically necessary and to counsel their patients about the proper use of antibiotics is the aim of a final rule published by the FDA in February. The rule outlines new labeling regulations designed to help reduce the development of antibiotic-resistant bacteria.
Antibiotics are often prescribed to children and adults with coughs or colds caused by viruses, not bacteria. Prescribing antibiotics for viral infections can hasten the development of bacterial strains that are resistant to that antibiotic. Antibiotic-resistant bacteria can be passed on to other people, making treatment of their illnesses even more complicated.
The new rule requires statements in the labels of human antibacterial drugs advising physicians to prescribe these drugs only to treat bacterial infections. The rule also requires a statement in the labeling encouraging physicians to counsel their patients about the proper use of these drugs.
More information on antibiotic resistance.
Every year, about 8,000 HIV-infected people who come to public clinics for HIV testing don't return a week later to receive their test results. With a rapid HIV test, results are available on the spot in about 20 minutes.
In January, HHS Secretary Tommy G. Thompson announced that the availability of a rapid HIV test would be extended from 38,000 laboratories to more than 100,000 sites, including physicians' offices and HIV counseling centers. The OraQuick Rapid HIV-1 Antibody Test, manufactured by OraSure Technologies Inc. of Bethlehem, Pa., is performed on a finger-stick sample of blood and provides results in as little as 20 minutes. Studies show the test has an accuracy rate of 99.6 percent. As with all HIV screening tests, if the OraQuick gives a reactive test result, the result must be confirmed with an additional specific test.
The FDA approved OraQuick last November for use in laboratories that perform tests of moderate complexity. Wider availability of the test is likely to increase overall HIV testing and decrease the number of people who are unaware they are infected with HIV.
A new regulation proposed by the FDA in March 2003 would, for the first time, establish standards to ensure that dietary supplements are not adulterated with contaminants or impurities. The regulation also would require current good manufacturing practices (CGMPs) for dietary supplements and ensure that manufacturers accurately label them to reflect the active ingredients and other ingredients in the products.
In recent years, analysis of dietary supplements by a private lab suggests that a substantial number of supplements may not contain the amounts of ingredients indicated on their product labels. In addition, the FDA has discovered products being marketed that are not accurately labeled or that contain harmful contaminants. For example, one firm recalled dietary supplements contaminated with excessive amounts of lead, which may have posed a health risk to many consumers, especially children and women of childbearing age. Another firm recalled its product after it was found that a dietary supplement containing folic acid, often taken by women to reduce the risk of having a baby with neural tube defects, contained only 35 percent of the amount of folic acid claimed on the label.
A new laboratory blood test that significantly increases a doctor's ability to rule out heart attacks in people who experience severe chest pains has been cleared for marketing by the FDA. The agency's action in February 2003 marks approval of the first new blood test for evaluation of heart attacks since 1994, when a blood test for troponin, a protein present in the blood after a heart attack, was introduced.
The latest product, Albumin Cobalt Binding (ACB) Test, manufactured by Ischemia Technologies Inc. of Arvada, Colo., works by measuring how much cobalt is bound to the blood protein albumin. Changes in the structure of albumin occur in several conditions, including heart attacks.
The ACB is not a stand-alone heart attack test. It is intended to be used along with an electrocardiogram (ECG) and a blood test that measures troponin. A normal ACB test with a normal ECG and normal troponin gives doctors increased confidence that a person did not have a heart attack.
The FDA has approved Alinia (nitazoxanide) for Oral Suspension to treat diarrhea caused by two parasitic infections--cryptosporidiosis and giardiasis--in children ages 1 through 11. Alinia is the first drug approved specifically to treat cryptosporidiosis, and it's the only drug in suspension form that is approved to treat giardiasis in this age group.
Cryptosporidiosis, an illness caused by the protozoan Cryptosporidium parvum, is characterized by diarrhea, abdominal cramps, loss of appetite, low-grade fever, nausea, and vomiting. Infected people may experience no symptoms, acute diarrhea, or persistent diarrhea that may continue for several weeks. The disease can be prolonged or life-threatening in severely immunocompromised people, and has been associated with malnutrition, impaired growth, and death in children in developing countries. Giardiasis, caused by the protozoan Giardia lamblia, is characterized by diarrhea, abdominal cramps, bloating, weight loss, or malabsorption. Giardiasis has also been associated with impaired growth in children in developing countries.
To date, the safety and effectiveness of Alinia has not been established in people who are HIV-positive or immunodeficient. In studies of children not infected with HIV, the most frequent problems reported in association with Alinia for Oral Suspension were mild, and included abdominal pain, diarrhea, vomiting, and headache.
Alinia is marketed by Romark Laboratories of Tampa, Fla.
Adults with moderate to severe plaque psoriasis now have a new option to relieve their symptoms--the first FDA-approved biologic treatment for this autoimmune condition.
Amevive (alefacept), an injected medication, treats plaque psoriasis through a unique immunosuppressive action. It is believed to work by simultaneously blocking and reducing the number of overactive white blood cells that play a role in psoriasis.
Plaque psoriasis is the most common form of psoriasis, a chronic relapsing disease of the skin that is characterized by scaling and inflammation. Psoriasis affects as many as 5.5 million Americans, according to the National Institutes of Health. Psoriasis is more common in adulthood, but may have its onset in childhood. People with psoriasis may have pain and itching, restricted motion in their joints, and emotional distress.
The approved labeling for Amevive states that it must be administered under the supervision of a physician and that physicians should inform patients of the need for regular monitoring of white blood cell counts while taking Amevive. Patients should also be informed that Amevive suppresses their immune system, which could increase their chances of developing an infection or malignancy.
Amevive is manufactured by Biogen Inc. of Cambridge, Mass.
A laboratory test to detect the presence in women of human papillomavirus (HPV), one of the most common sexually transmitted infections, has been approved for an expanded use.
The FDA initially approved the HC2 High-Risk HPV DNA Test in 2000 for testing women who had abnormal Pap test results to determine whether they needed to be referred for further examination. The expanded use allows the test to be used, in conjunction with the Pap test, for screening of women over age 30 for HPV infection.
Most women who become infected with HPV are able to eradicate the virus and suffer no apparent long-term consequences to their health. But a few women develop a persistent infection that can eventually lead to pre-cancerous changes in the cervix. The HPV DNA test can identify 13 of the high-risk types of HPV associated with the development of cervical cancer. With proper screening, cervical cancer is avoidable and, if caught early, curable.
The HPV DNA test, manufactured by Digene Corp. of Gaithersburg, Md., is not intended to substitute for regular Pap screening.
Some of the gene therapy trials temporarily halted by the FDA in January may be allowed to continue if appropriate safeguards are put in place.
The FDA had placed the studies on hold after it learned that two children treated in a French gene therapy trial had developed a leukemia-like condition. The children had been successfully treated by gene therapy for X-linked severe combined immunodeficiency disease (X-SCID), also known as "bubble baby syndrome."
In February, an FDA advisory committee recommended possible safety measures to minimize the risks in human studies that use retroviral vectors. These modified viruses are used to insert new genes into blood stem cells to treat life-threatening diseases. These safety measures include revisions to the informed consent document for patients and steps study sponsors should take to monitor for early leukemia-like symptoms.
The FDA's continuing review of adverse event reports from all U.S. studies involving retroviral vectors has so far found no evidence of leukemia caused by the gene therapy. The FDA is reviewing the recommendations of the advisory committee and working closely with study sponsors to help them continue to develop innovative new treatments, while doing everything possible to better understand and prevent any adverse events.
The FDA's Office of Criminal Investigations recently uncovered the existence of a counterfeit version of a drug used to treat severe anemia. Investigators say that the illicit vials, labeled Procrit, contain bacteria and represent a significant potential health hazard to consumers.
Procrit (epoetin alpha) is used to treat severe anemia by stimulating the production of red blood cells.
In addition to finding bacteria, FDA laboratory testing demonstrated that some of the counterfeit product contains no active ingredient. Ortho Biotech Products L.P. of Bridgewater, N.J., issued a warning to health care providers and others in a letter dated March 8, 2003.
The three lots of counterfeit products, labeled as Procrit (epoetin alpha), 40,000 units/mL, are:
The FDA urges health care providers and consumers to check packaging and vials very carefully before using this product. Anyone who finds counterfeit Procrit should not use it, should isolate it, and should immediately contact the FDA's Center for Biologics Evaluation and Research at 1-800-835-4709 and Ortho Biotech at 1-800-325-7504. For more information, visit Ortho's Web site at www.procrit.com/counterfeit/letter.html.
People infected with the virus that causes AIDS and who no longer respond to other treatments now have another option with approval of a new class of medications. Fuzeon (enfuvirtide) was approved by the FDA in March for use in combination with other drugs that fight HIV.
Fuzeon is the first "fusion inhibitor" drug. When HIV infects a cell, it first attaches to the outside surface of the cell. Then the virus fuses its membrane with the infected cell's membrane, thereby introducing the virus into the cell. Fuzeon stops this process of fusion.
According to the Centers for Disease Control and Prevention, 850,000 to 950,000 people in the United States are currently infected with HIV. About 40,000 new infections occur each year. The new class of medications is particularly timely since a significant percentage of patients with chronic HIV have developed infection resistant to many existing medications.
A combination of medications is needed for effective HIV treatment, experts say. Fuzeon, manufactured by Roche Pharmaceuticals of Nutley, N.J., can be used as part of a medication regimen in patients for whom there are limited options. Fuzeon is administered as an injection and should be used only in adults and children ages 6 years and older who have previously used other anti-HIV medications and who have ongoing evidence of viral replication.
The FDA has cleared for use by the U.S. military a liquid decontamination lotion intended to remove or neutralize chemical warfare agents and T-2 fungal toxin from the skin.
The lotion, called Reactive Skin Decontamination Lotion (RSDL), must be applied to exposed skin as soon as possible after exposure to a chemical agent.
The lotion is impregnated in a sponge pad packaged as a single unit in a heat-sealed foil pouch. When exposed to chemical warfare agents, the user wipes the exposed skin with the lotion. The lotion removes the agents or the T-2 toxin and also reacts with the chemical agents, rapidly neutralizing them to make them non-toxic.
"If used in time, this lotion can help prevent the serious burns and deaths that result from exposure to chemical warfare agents," says FDA Commissioner Mark B. McClellan, M.D., Ph.D. "The FDA worked with the U.S. Army to expedite review of this product to make it available to our men and women in uniform as quickly as possible."
The FDA cleared the lotion for use based on studies conducted by the U.S. Department of the Army that showed it is safe and effective. The Army tested the product's safety by conducting skin irritation, sensitization, and photoirritation studies in more than 300 people. It tested the lotion's effectiveness by using it to treat animals that had been exposed to chemical agents. The Canadian military and the U.S. military worked together to develop the scientific data on which the FDA based clearance of the product.
RSDL is manufactured by O'Dell Engineering Ltd./E-Z-EM Canada Inc., Canada.
The FDA has issued a public health advisory concerning Lindane Lotion and Lindane Shampoo, prescription medication treatments for scabies and lice.
The advisory announces significant changes to the labeling of these products, which now includes a boxed warning emphasizing that Lindane products are indicated as a second-line therapy. The FDA believes the benefits of Lindane outweigh the risks when used as directed. But given the potential for neurotoxicity, people should only be treated with these medications if others are not tolerable or have failed.
The boxed warning also states that Lindane Lotion and Lindane Shampoo should be used with caution in people who weigh less than 110 pounds. Lindane is not recommended for use in infants, especially premature infants. These warnings are based on reports to the FDA of problems in children.
It is estimated that up to 1 million prescriptions are written each year in the United States to treat new cases of head lice and scabies, which occur mostly in school-age children. Because Lindane is absorbed through the skin, and because younger children have more skin surface area per pound of body weight than adults, the amount absorbed may result in higher blood levels of Lindane in children than in adults. Because most of the serious adverse events reported with Lindane products are due to misuse and overuse, especially with the lotion, product package sizes will be limited to 1 and 2 ounces. It is very important that consumers use this medication in a manner consistent with the product labeling. Instructions and warnings for Lindane products will be given to consumers in a Medication Guide.
Health care providers should consider this new safety information when deciding whether to prescribe Lindane Lotion or Lindane Shampoo.
U.S. Marshals have seized contaminated imported honey at the request of the FDA in three enforcement actions since last fall. The latest action occurred in February in Baytown, Texas, where marshals took possession of 266 drums of honey (each containing 639 pounds of bulk honey) and five totes (each containing a net weight of 3,000 pounds) from Hoyts Honey Farm Inc. Earlier seizures took place in Texas and Louisiana.
The import seizures occurred after the FDA tested and confirmed the presence of chloramphenicol, an antibiotic and an unapproved food additive. Food products that contain chloramphenicol cannot be sold in or imported into this country, in accordance with the Federal Food, Drug and Cosmetic Act.
Chloramphenicol is a broad-spectrum antibiotic drug used to treat life-threatening infections in humans, usually when other alternatives are not available. Use of this antibiotic is limited because of a potentially life-threatening side effect, idiosyncratic aplastic anemia.
The FDA will continue to detain or seize any honey imports that contain chloramphenicol to ensure that this product is not released for human or animal consumption in the United States.
In the chart that accompanied "The Lowdown on Depression" (January-February 2003 FDA Consumer), some drugs were incorrectly identified as "selective serotonin reuptake inhibitors" (SSRIs). Of the 10 drugs listed as "Serotonin transport blockers" only five are SSRIs: Celexa (citalopram), Prozac (fluoxetine), Luvox (fluvoxamine), Paxil (paroxetine), and Zoloft (sertraline). The other drugs listed, though their actions include serotonin transport blockade, are not SSRIs since they have other pharmacological actions as well.