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Phase
I trial of temozolomide (CCRG 81045: M&B 39831: NSC 362856)
Newlands ES, Blackledge GR, Slack JA, Rustin GJ, Smith DB, Stuart NS,
Quarterman CP, Hoffman R, Stevens MF, Brampton MH, et al.
Department of Medical Oncology, Charing Cross Hospital,
Hammersmith, London, UK
Temozolomide (CCRG 81045: M&B 39831: NSC 362856) is an analogue of
mitozolomide displaying similar broad spectrum activity in mouse tumours, but
showing considerably less myelosuppression in the toxicology screen.
Temozolomide was initially studied intravenously at doses between 50-200 mg m-2
and subsequently was given orally up to 1,200 mg m-2.
A total of 51 patients
were entered on the single dose schedule.
Temozolomide exhibits linear
pharmacokinetics with increasing dose.
Myelotoxicity was dose limiting.
Experimentally, temozolomide activity was schedule dependent and therefore oral
administration was studied as a daily x 5 schedule between total doses of 750
and 1,200 mg m-2 in 42 patients.
Myelosuppression was again dose limiting.
The
recommended dose for Phase II trials is 150 mg m-2 po for 5 days (total dose 750
mg m-2) for the first course, and if no major myelosuppression is detected on
day 22 of the 4 week cycle, the subsequent courses can be given at 200 mg m-2
for 5 days (total dose 1 g m-2) on a 4 week cycle.
Mild to moderate nausea and
vomiting was dose related but readily controlled with antiemetics.
Clinical
activity was detected using the 5 day schedule in four (2CR, 2PR; 17%) out of 23
patients with melanoma and in one patient with mycosis fungoides (CR lasting 7
months).
Two patients with recurrent high grade gliomas have also had partial
responses.
Temozolomide is easy to use clinically and generally well tolerated.
In the extended Phase I trial temozolomide only occasionally exhibited the
unpredictable myelosuppression seen with mitozolomide.
PMID: 1739631 [PubMed - indexed for
MEDLINE]
Source: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1739631&dopt=Abstract |