Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023380 (lethargy)
 5,697 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Maytansine, a new ansa macrolide antitumor antibiotic, was administered to a total of 107 patients in a Phase I-II study. Dose-limiting toxic reactions which occurred at 0.75-1.0 mg/M2 in both Phase I and II were neurologic and consisted primarily of lethargy/weakness (a debilitation syndrome) and paresthesias. Gastrointestinal and neurologic toxic reactions increased in frequency and severity as a function of dose. Myelosuppression, while infrequent, occurred only in previously treated patients. Changes in liver function tests were subclinical. Two partial remissions were observed at a dose-level of 0.5 mg/M2 in Phase I:1 patient with squamous cell carcinoma of the lung responded for five weeks, while the other patient with adenocarcinoma of the lung responded for four weeks. One partial remission, lasting 14 weeks was seen in Phase II in a patient with malignant melanoma treated at dose-level of 1.0 mg/M2. All responses were in heavily pretreated patients. pairs of small bowel biopsy specimen used to define the mitotic index demonstrated peak mitotic arrest at 24 hours in contrast to vinca alkaloids which appear to have a peak mitotic arrest at 12-24 hours.
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PMID:A phase I-II study of maytansine utilizing a weekly schedule. 721 95

Maytansine is an experimental antitumor agent that has shown minimal efficacy against breast cancer with minimal myelosuppression in phase I trials. Forty-one patients with advanced drug-resistant breast cancer were treated with a 5-day intermittent iv infusion of maytansine repeated every 21 days. All patients had been heavily pretreated with cyclophosphamide, methotrexate, 5-fluorouracil, or doxorubicin, and 12 had received vinblastine, mitomycin C, or investigational drugs. All patients had measurable disease and an expected survival of 6 weeks. The average performance status was 2.5. Twelve patients did not complete one full cycle of therapy, leaving 29 evaluable for response. One patient had a partial regression of pulmonary disease, seven had transient responses of less than 50% reduction in tumor or stable disease, and 21 had progressive disease. Toxic effects (vomiting, diarrhea, ileus, lethargy, and altered mentation) were considerable. Since maytansine is a relatively nonmyelotoxic metaphase inhibitor, we feel that even minimal efficacy in heavily pretreated patients justifies further evaluation of the agent in combination therapy.
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PMID:Minimal single-agent activity of maytansine in refractory breast cancer: a Southwest Oncology Group study. 742 53