| Archives
2002
February
January
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Vitamin
B Formula Reduces Restenosis
After Angioplasty
Researchers say they’ve demonstrated how an inexpensive
adjunctive treatment with minimal adverse effects can
reduce the risk of restenosis after coronary angioplasty.
In a recent double-blind study, more than 200 patients
took either a placebo or a combination of folic acid,
vitamin B12, and pyridoxine for six months following their
angioplasty. The vitamin B therapy significantly lowered
plasma homocysteine levels, which researchers believe
may be a key mechanism behind the clinical benefits they
saw in the study. These benefits included a significantly
larger minimal luminal diameter in patients receiving
the vitamin B therapy and a significantly lower rate of
restenosis (19.6% vs. 37.6% with placebo). Furthermore,
patients receiving the vitamin B therapy had a significantly
reduced need for revascularization (10.8% vs. 22.3%) of
the target lesion. Primarily because of this reduction,
say the researchers, the group receiving the vitamin B
combination had a lower incidence of major adverse cardiac
events at six months.
Schnyder,
G., Roffi, M., et al. (2001). Decreased rate of coronary
restenosis after lowering of plasma homocysteine levels.
N Engl J Med, 345(22), 1593.
[TOP]
New
Drug Cuts Risk Of DVT In Hip And Knee Surgeries
In an expedited review, the FDA has approved fondaparinux
sodium (Arixtra) injection for prophylaxis against deep
vein thrombosis (DVT) in patients undergoing surgery for
hip fracture, hip replacement, or knee replacement. The
drug, the first in a new class of synthetic antithrombotic
agents, selectively inhibits factor Xa, a key component
in the clotting process. Its efficacy and safety were
demonstrated in double-blind trials in 8,000 patients.
Because serious bleeding is the major adverse effect of
fondaparinux, it shouldn’t be used in patients who
are at increased risk of bleeding. This includes patients
with severely impaired kidney function, those who weigh
less than 110 pounds, and the elderly. Fondaparinux also
shouldn’t be given to patients receiving spinal anesthesia
or spinal puncture because of the risk of spinal embolism.
U.S.
Food and Drug Administration. “FDA approves new anti-clotting
drug.” 2001. www.fda.gov/bbs/topics/answers/2001/ans01125.html
(11 Dec. 2001).
[TOP]
First
Oral Agent For Pulmonary Arterial Hypertension Gets Approval
The FDA recently approved the first oral medication for
the treatment of pulmonary arterial hypertension (PAH).
Previous treatments for PAH required a central IV line
and infusion pump. The new drug, bosentan (Tracleer) tablets,
is taken twice a day. It blocks the action of the hormone
endothelin, which narrows blood vessels and raises blood
pressure. In placebo-controlled trials, the addition of
bosentan to patients’ regimens significantly increased
their ability to exercise. Monthly liver enzyme testing
and pregnancy testing are required, however, to prevent
two important risks—liver toxicity and major birth
defects. Bosentan shouldn’t be used in pregnant women,
and because the drug may alter the metabolism of hormonal
contraceptives, those methods of birth control need to
be supplemented with other means. Bosentan can only be
prescribed through the Tracleer Access Program. For details,
call (866) 228-3546. U.S. Food and Drug Administration.
“FDA
approves first oral medication for pulmonary arterial
hypertension.” 2001. www.fda.gov/bbs/topics/answers/2001/ans01121.html
(26 Nov. 2001).
[TOP]
Drug
Regimen For Latent TB Linked To Severe Liver Injuries
The Centers for Disease Control and Prevention (CDC) and
the American Thoracic Society have revised treatment recommendations
for latent tuberculosis infection (LTBI) after receiving
reports of 21 cases of severe liver injury—including
five deaths—in patients on a two-month regimen of
rifampin (Rifadin) and pyrazinamide, two agents used in
the combination product Rifater. The revisions state that,
in most instances, a nine-month course of isoniazid (INH)
is the preferred regimen, and that it should be the standard
treatment for patients also infected with HIV. The revisions
detail which patients to test and treat for LTBI. Rifampin-pyrazinamide
may be used in selected cases, but with more intensive
clinical and lab monitoring than previously recommended,
with in-person reassessments every two weeks. Patients
should be informed about the risks of therapy and told
to stop taking the drugs if they develop abdominal pain,
begin vomiting, or develop jaundice or other hepatitis
symptoms. Similar advice may apply to all patients, since
10 cases of liver injury with other LTBI treatments have
been reported.
Centers
for Disease Control and Prevention. “Update: Fatal
and severe liver injuries associated with rifampin and
pyrazinamide for latent tuberculosis infection, and revisions
in American Thoracic Society/CDC recommendations—United
States, 2001.” MMWR. August 31, 2001. www.cdc.gov/mmwr/preview/mmwrhtml/mm5034a1.htm
(5 Sept. 2001).
[TOP]
Combination
Therapy Gets Approval For Metastatic Breast CA
Two existing cancer therapies—capecitabine (Xeloda)
and docetaxel (Taxotere)—have been approved as a
combination treatment for patients with metastatic breast
cancer whose disease has progressed after treatment with
an anthracycline-containing cancer agent, such as doxorubicin
HCl (Adriamycin). In an open-label study in 511 patients,
capecitabine/docetaxel brought improvements in response
rates, time to worsening of disease, and survival, compared
to docetaxel alone. Patients should be cautioned about
the risk of adverse effects, which include GI symptoms,
painful inflammation of the mouth, fatigue, painful swelling
or redness of the hands or feet, and bone marrow suppression.
Dose reduction or the interruption or discontinuation
of therapy may be indicated if these reactions occur.
Capecitabine has a significant interaction with oral anticoagulants
derived from coumarin, such as warfarin (Coumadin), which
can result in serious bleeding complications.
U.S.
Food and Drug Administration. “FDA approves Xeloda
in combination with Taxotere for advanced breast cancer.”
2001. www.fda.gov/bbs/topics/answers/2001/ans01101.html
(11 Sept. 2001).
[TOP]
RA
Sufferers Have A More Selective Treatment Option
Adults with moderate to severe rheumatoid arthritis (RA)
that doesn’t respond to disease-modifying antirheumatic
drugs (DMARDs) have a new alternative: anakinra (Kineret).
The new agent selectively blocks interleukin-1, an important
mediator of inflammation and joint destruction. RA patients
have an excess of this protein. Anakinra is administered
once daily by subcutaneous injection into the stomach,
arm, or thigh, and it can be used alone or in combination
with other DMARDs. More than 2,600 patients received anakinra
in clinical trials. After six months of therapy, 38% achieved
a 20% improvement in inflammation and pain symptoms, compared
with 22% achieving that level of improvement on placebo.
The most common adverse effect was a mild injection site
reaction, but the risk of serious infections was higher
with anakinra than with placebo (2% vs. less than 1%).
Anakinra shouldn’t be used with tumor necrosis factor
(TNF) blockers such as etanercept (Enbrel) and infliximab
(Remicade) because of a higher risk of serious infection
and neutropenia.
Based
on a news release from Amgen, November 14, 2001, “FDA
approves Kineret for the treatment of rheumatoid arthritis.”
www.amgen.com/news/news01/pressrelease011114.html (15
Nov. 2001).
Therapy
Reduced Deaths From Severe Sepsis
A genetically engineered version of activated protein
C has been approved as the first biologic treatment for
the most severe forms of sepsis. Drotrecogin alfa (activated),
marketed under the brand name Xigris, is approved for
use in adults with severe sepsis (associated with acute
organ dysfunction) who have a high risk of death, as determined
by standardized assessment scores. In a 28-day study involving
nearly 1,700 patients, Xigris reduced the mortality rate
in patients at high risk of death from 44% to 31%. Bleeding,
including intracranial hemorrhage, is the most serious
adverse effect (the protein interferes with blood clot
formation). During the study’s four-day infusions,
serious bleeding occurred in 2.4% of patients treated
with Xigris compared to 1% in the placebo group. The new
treatment shouldn’t be used in patients who have
active internal bleeding or conditions that put them at
high risk for bleeding.
U.S.
Food and Drug Administration. “FDA approves first
biologic treatment for sepsis.” 2001. www.fda.gov/bbs/topics/news/2001/new00780.html
(26 Nov. 2001).
New
Crohn’s Disease Therapy Has Fewer Steroid Side Effects
A capsule formulation of the steroid budesonide has been
approved for the treatment of mild to moderate active
Crohn’s disease involving the ileum and/or ascending
colon. The new product, Entocort EC capsules, releases
budesonide (a corticosteroid) in the intestine, where
the drug works locally and topically to decrease inflammation.
Because little of the drug enters the systemic circulation,
patients are less likely to have the typical adverse effects
associated with conventional steroids used to treat the
disorder. In a study comparing the new therapy with prednisolone
in 651 Crohn’s disease patients, the most common
adverse events with budesonide capsules were headache,
respiratory infection, and nausea. Fewer budesonide patients
experienced facial swelling and acne, compared to those
receiving prednisolone. The recommended dosage is three
capsules once daily for up to eight weeks.
U.S.
Food and Drug Administration. “FDA approves new treatment
for Crohn’s disease.” 2001. www.fda.gov/bbs/topics/answers/2001/ans01106.html
(9 Oct. 2001).
OTC
Talk
Know Your Antacids— And Who’s Taking Them Antacids
are so commonly used that patients may not even mention
them when you take a drug history. Even more worrisome
is the fact that your patients may not realize that these
drugs have side effects or that they can pose serious
problems for those who have renal insufficiency. Consider,
for instance, sodium bicarbonate (Alka-Seltzer, Citrocarbonate,
others), which is a potent antacid. Because it’s
absorbed systemically, it can produce systemic alkalosis
as well as belching and gas. On the other end of the potency
spectrum are the antacids that contain aluminum (Rolaids,
Gaviscon, others). Though they have the lowest potency
of the available antacids, they can still cause constipation
and put patients with renal failure at risk for aluminum
toxicity. Magnesium-containing antacids (Mylanta, Maalox,
others) can cause diarrhea. In patients with renal dysfunction,
there’s also a risk of magnesium toxicity. And while
some calcium-containing antacids (Tums, Mylanta Ultra
Tabs, others) have become popular as calcium supplements,
they can lead to hypercalcemia as well as constipation
in some patients. For all these reasons, ask patients
about their antacid use and remind them to read the labels.
Source: Physicians’ desk reference for nonprescription
drugs and dietary supplements (22nd ed.). (2001). Montvale,
NJ: Thomson Healthcare/ Medical Economics.
THE
AUTHOR JAMES W. WOOTEN, a member of the RN editorial
board, is an assistant professor of medicine at the University
of Missouri School of Medicine, in Kansas City, Mo.
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