FDA Approves Lamictal, an Extended-Release Once-Daily, New Generation Treatment

FDA Approves Lamictal(R)XR(TM); An Extended-Release Once-Daily, New Generation Treatment...

RESEARCH TRIANGLE PARK, N.C., June 1 /PRNewswire-FirstCall/ -- GlaxoSmithKline
(NYSE: GSK) announced today that the U.S. Food and Drug Administration has
approved Lamictal(R)XR(TM) (lamotrigine) Extended-Release Tablets as
once-a-day add-on therapy for epilepsy patients 13 years of age or older with
partial onset seizures. Lamictal XR reduced seizures in patients who were

inadequately controlled on current therapy.

Lamictal XR reduced the frequency of partial seizures during a 19-week study.
More patients who took Lamictal XR had a significant reduction in seizure
frequency compared with placebo. These results were statistically significant.
Patients enrolled in the study were inadequately controlled on one or two
antiepileptic drugs. In fact, half of these patients were inadequately
controlled on two antiepileptic drugs.

"Many patients require multiple doses of one or more medications to control
their epilepsy, which makes taking their medicines even more challenging,"
said Dean Naritoku, M.D., Professor and Chairman of Neurology, University of
South Alabama, Mobile, AL. "Lamictal XR is an important once-daily advance for
patients with epilepsy who still experience seizures while taking their

current therapy."

Lamictal XR is approved as add-on therapy for adult and adolescent patients
who experience partial seizures with or without secondary generalization.
Partial seizures, which are limited to one part of the brain, are the most
common type of seizure experienced by people with epilepsy. Partial seizures
may sometimes spread to affect the entire brain, an occurrence classified as
secondary generalization. The safety and effectiveness of Lamictal XR have not
been established in patients under the age of 13.

Patients with partial seizures currently taking immediate-release Lamictal
twice-daily can be converted directly to once-a-day Lamictal XR using the same

total daily dose. Lamictal XR will be available in pharmacies this summer.

Patented GlaxoSmithKline Extended-Release Technology

Lamictal XR Extended-Release Tablets are enteric-coated and contain a modified
release formulation in the center of the tablet. There is a specially designed
opening in the enteric coating on both sides of the tablet that utilizes a new
technology called DiffCORE(TM), discovered and developed by GlaxoSmithKline.
This allows a controlled release of the medicine in the acidic environment of
the stomach, leading to a gradual release of lamotrigine into the bloodstream.

Safety Information

Prescription Lamictal XR (lamotrigine) Extended-Release Tablets are not for
everyone. LamictalXR may cause a serious skin rash that may cause the patient
to be hospitalized or to stop Lamictal XR; it may rarely cause death. There is
no way to tell if a mild rash will develop into a more serious reaction. These
serious skin reactions are more likely to happen when the patient begins
taking Lamictal XR, within the first two to eight weeks of treatment. But it
can happen in people who have taken LamictalXR for any period of time.
Children between two to 16 years of age have a higher chance of getting this
serious skin reaction while taking lamotrigine. Lamictal XR is not approved
for use in children less than 13 years old.

The risk of getting a rash is higher if taking Lamictal XR while taking
valproate (Depakene(R) (valproic acid) or Depakote(R) (divalproex sodium),
taking a higher starting dose of Lamictal XR than a healthcare provider
prescribed or increasing the dose of Lamictal XR faster than prescribed.

Lamictal XR can also cause other types of allergic reactions or serious
problems which may affect organs and other parts of your body like the liver
or blood cells. The patient may or may not have a rash with these types of
reactions.

The patient should call their healthcare provider right away if they have any
of the following: a skin rash, hives, fever, swollen lymph glands, painful
sores in the mouth or around the eyes, swelling of the lips or tongue,
yellowing of the skin or eyes, unusual bruising or bleeding, severe fatigue or
weakness, severe muscle pain or frequent infections. These symptoms may be the
first signs of a serious reaction. A healthcare provider should examine the
patient to decide if they should continue taking Lamictal XR.

Antiepileptic drugs, including Lamictal XR, increase the risk of suicidal
thoughts or behavior in patients taking these drugs for any indication.
Patients treated with any antiepileptic drug for any indication should be
monitored for the emergence or worsening of depression, suicidal thoughts or
behavior, or any unusual changes in mood or behavior.

Patients, their caregivers, and families should be informed that antiepileptic
drugs increase the risk of suicidal thoughts and behavior and should be
advised of the need to be alert for the emergence or worsening of the signs
and symptoms of depression, any unusual changes in mood or behavior, or the
emergence of suicidal thoughts, behavior, or thoughts about self-harm.
Behaviors of concern should be reported immediately to healthcare providers.

Medication errors involving Lamictal have occurred. In particular, the name
Lamictal or lamotrigine can be confused with the names of other commonly used
medications. Medication errors may also occur between the different
formulations of Lamictal. To reduce the potential of medication errors,
healthcare professionals should write and say Lamictal XR clearly. Depictions
of the Lamictal XR can be found in the Medication Guide. To avoid the
medication error of using the wrong drug or formulation, patients should be
strongly advised to visually inspect their tablets to verify that they are
Lamictal XR each time they fill their prescription.

Patients should not take Lamictal XR if they have had an allergic reaction to
lamotrigine or to any of the inactive ingredients.

Common side effects of Lamictal XR include dizziness, diarrhea, weakness and
fatigue, difficulty with coordination or balance, tremor, hot flashes, double
vision, nausea, depression, muscle ache, and nervousness. Other common side
effects that have been reported with another form of Lamictal include
headache, sleepiness, and vomiting. Patients should tell their healthcare
provider about any side effect that bothers them or does not go away; patients
should tell their healthcare provider if they have any changes in their
menstrual pattern, such as breakthrough bleeding, while taking Lamictal XR and
birth control pills. These are not all the possible side effects of Lamictal
XR.

For full prescribing information for Lamictal XR, including Boxed Warning,
please visit www.gsk.com.

Editors' Note: About the Studies

FDA approval of Lamictal XR (lamotrigine) was based on data from the ARMOR
study, an international, multi-center, randomized, double-blind,
placebo-controlled trial of 236 patients 13 years of age or older with
inadequately controlled partial seizures, who were taking a stable regimen of
one or two antiepileptic drugs (AEDs) and experienced eight or more partial
seizures during the eight-week baseline phase of the study. Patients in the
baseline period were experiencing four to six seizures per week prior to being
randomized to either Lamictal XR or placebo. The treatment period of the study
consisted of a seven-week Escalation Phase and a 12-week Maintenance Phase.

Study results showed that the new once-daily, extended-release formulation of
Lamictal XR reduced partial seizures by 47 percent, compared to 25 percent
with placebo over the entire 19-week treatment period (P=0.0001).

A second study, COMPASS, was an open-label study evaluating the conversion
from the immediate-release form of Lamictal given twice daily to the same
total daily dose of Lamictal XR given once daily in 44 patients 13 years or
older with epilepsy. Patients enrolled in the study were divided into three
treatment groups based on the type of adjunctive antiepileptic drug they were
taking. The rate at which Lamictal clears the bloodstream varies depending
upon the other antiepileptic drugs a patient may be taking at the same time.
The study results from COMPASS showed that patients could be switched from the
immediate-release formulation of Lamictal taken twice daily to the same total
daily dose of Lamictal XR taken once daily while maintaining comparable
minimum blood levels of lamotrigine, regardless of the other antiepileptic
medicines being taken concurrently.

The most common adverse events in the ARMOR study are presented above in the
About Lamictal XR section. The most common drug-related adverse event in the
COMPASS study was headache. No serious rashes were observed in either
treatment group in both the ARMOR and COMPASS studies. However, the risk of
serious rash caused by Lamictal XR is not expected to differ from that of with
the immediate-release formulation of Lamictal. The prescribing information for
Lamictal XR contains a boxed warning on serious rash that is further described
in the About Lamictal XR section above.

GlaxoSmithKline - one of the world's leading research-based pharmaceutical and
healthcare companies - is committed to improving the quality of human life by
enabling people to do more, feel better and live longer. For further
information please visit www.gsk.com

*Depakene and Depakote are registered trademarks of Abbott Laboratories

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