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This is Your Brain on Drugs
Temodar: Is it right
for you?
 What
is Temodar?
Temodar®, or temozolomide, is a oral chemotherapy drug approved last year by the
Food and Drug Administration for the treatment of anaplastic astrocytoma.
Temodar is one of the few drugs specifically approved for the treatment of brain
tumors (others: BCNU, CCNU, Gliadel®) based on studies demonstrating complete
and partial remissions in anaplastic astrocytoma patients previously treated
with radiation therapy and chemotherapy.
How is Temodar different from the other
drugs?
Chemically, Temodar resembles an older drug, dacarbazine, also called DTIC.
DTIC is an intravenous drug that has been used in the treatment of melanoma,
Hodgkin's disease, and other cancers. Temodar and DTIC are converted into the
same active compound; but, unlike DTIC, Temodar does not have to be converted
into the active drug in the liver. Also, Temodar appears to have better
penetration across the blood-brain barrier.
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| Patient's MRI results: before
(left) and after (right) treatment with Temodar. |
Is Temodar being used for tumors
other than anaplastic astrocytoma?
Yes - and no. There are studies of Temodar in other brain tumor types,
particularly glioblastoma multiforme (GBM), which is more common than anaplastic
astrocytoma. Temodar appears to benefit some GBM patients, but it in many cases
appears to slow down or halt the growth of the tumor rather than shrink it. It
has been used in low-grade tumors, including oligodendroglioma. A study is
currently in progress for primary central nervous system lymphoma. Some
physicians, however, are hesitant to use Temodar in patients who have a tumor
other than anaplastic astrocytoma, because relatively little is known about its
long-term effectiveness and side effects, compared with the older drugs.
Does Temodar have advantages
over other brain tumor drugs?
Temodar, procarbazine, and CCNU are all oral drugs; but only Temodar and
procarbazine have been compared in a study. In that study, in patients with
recurrent GBM, Temodar was slightly better in effectiveness, overall survival,
and side effects. Studies comparing Temodar with other drugs have not yet been
completed.
Temodar is an oral drug, which is
an advantage for patients who dislike the inconvenience of intravenous
medication. It appears to be associated with fewer side effects than some other
drugs, but can still cause nausea, fatigue, and low blood counts.
Are there disadvantages to
Temodar?
All drugs have potential side effects, and Temodar, as a chemotherapy drug,
is no exception. It can cause low blood counts, fatigue, nausea, and
constipation. It usually does not cause hair loss. Temodar is not available as a
generic and is expensive, ranging from $1200-1800 a month for most patients. In
many cases, however, the drug may be obtained at reduced cost or covered by
insurance.
Is Temodar used with other
drugs?
There have been some studies, both in animals and in patients, that suggest
that Temodar can be used safely with other drugs, particularly BCNU, CCNU, and
cisplatin. There may be some synergy (additive effects) when these drugs are
used in combination.
What is the best way to
take Temodar?
At the present time, no one knows if there is an "optimal" way to take
Temodar. Some studies in Europe, where temozolomide was developed several
years ago, have used it at low doses, daily, over a period of up to seven
weeks. The FDA recommends a five-day schedule, given once every four
weeks, because that was the schedule used in the United States clinical
trials. The dose for an individual patient is calculated according to the
patient's height and weight (the body surface area, or BSA) which usually
ranges between 1.6 and 2.2. |
"Having had other chemotherapy, I can
truly say that Temodar is easier to take, with fewer side effects."
|
The recommended dose is modified if
the patient has previously had chemotherapy. Patients previously treated with
chemotherapy may have lower blood counts than those who have not had other
treatment.
On a five day schedule, patients
usually take the drug Monday though Friday, although of course any five-day
period can be used. Patients usually take Temodar fasting, after their evening
meal, and after an anti-nausea drug. Normally, when the blood counts are not too
low, Temodar is taken the same time every month.
How many months of treatment
with Temodar are recommended?
Good question! Temodar has been given safely, with tolerable side effects,
every four weeks up to two years. Some physicians recommend that, when used
after surgery and radiation therapy for anaplastic astrocytoma, a total of six
months of therapy. For patients who have complete disappearance of their tumor
while on Temodar, there is no evidence that continuing to take the drug will be
of benefit (but there is apparently no additional harm up to two years, except
for continuing side effects). It is recommended that all patients continuing on
Temodar have routine follow up CT or MRI scans. Tumors can and do become
resistant to therapy even when the drug has been effective in the past.
Will Temodar cure a brain tumor?
The experience with Temodar in the United States is relatively brief. "Cure"
usually implies that the disease treated is eradicated totally and permanently,
never to recur. While it is certainly possible that some patients treated with
Temodar who have had a remission (absence of symptoms and brain scan
abnormalities) are cured, it is far too early to make this claim.
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