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Sumithra Mandrekar

Publications and source records attributed to Sumithra Mandrekar.

9 recordsLinked to original sources
PubMed2006

An adaptive dose-finding design incorporating both toxicity and efficacy.

Novel therapies are challenging the standards of drug development. Agents with specific biologic targets and limited toxicity require novel designs to determine doses to be taken forward into larger studies. In this paper, we describe an approach that incorporates both toxicity and efficacy data into the estimation of the biologically optimal dose of an agent in a phase I trial. The approach is based on the flexible continuation-ratio model, and uses straightforward optimal dose selection criteria. Dose selection is based on all patients treated up until that time point, using a continual reassessment method approach. Dose-outcome curves considered include monotonically increasing, monotonically decreasing, and unimodal curves. Our simulation studies demonstrate that the proposed design, which we call TriCRM, has favourable operating characteristics.

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PubMed2005

A phase I trial of celecoxib in combination with docetaxel and irinotecan in patients with advanced cancer.

PURPOSE: This phase I study was conducted to determine the safety, tolerability and maximum tolerated dose of the combination of celecoxib, a selective cyclooxygenase-2 inhibitor, with docetaxel and irinotecan, in patients with advanced solid tumors. PATIENTS AND METHODS: Patients with solid tumors received one of three escalating dose levels of daily celecoxib in combination with docetaxel and irinotecan administered on days 1 and 8 of an every 21-day cycle. Toxicities were graded by the National Cancer Institute Common Toxicity Criteria (NCI CTC) and recorded as maximum grade per patient for each treatment cycle. RESULTS: A total of 19 patients received 90 cycles of treatment through three dose levels. Dose-limiting toxicities were nausea and diarrhea. The most common treatment-related toxicities in all cycles of treatment were alopecia, fatigue, diarrhea, nausea, vomiting, anemia, anorexia, and edema.. The maximum tolerated dose was established at celecoxib 400 mg twice a day continuously, weekly docetaxel 30 mg/m2 and irinotecan 50 mg/m2 for 2 weeks every 21 days. Disease stabilization (five or more cycles) was documented in eight patients. CONCLUSION: The combination of celecoxib with docetaxel and irinotecan did not ameliorate irinotecan-induced diarrhea. Although prolonged disease stabilization was achieved in some patients, we do not recommend combining celecoxib with docetaxel and irinotecan because of lack of activity and the side effect profile of this combination.

Adult↗
PubMed2005

Results of combined-modality therapy for limited-stage small cell lung carcinoma in the elderly.

BACKGROUND: A Phase III trial was conducted by the North Central Cancer Treatment Group to determine whether chemotherapy (etoposide and cisplatin) plus either twice-daily radiotherapy (BIDRT) or once-daily radiotherapy (QDRT) resulted in a better outcome for patients with limited-stage small cell lung carcinoma (LD-SCLC). No difference in survival was identified between the two arms. The current analysis examined the relation between age and outcome for patients treated during this trial. METHODS: The current study included 263 patients with LD-SCLC and an Eastern Cooperative Oncology Group performance status of < or = 2 who were randomized to receive QDRT or split-course BIDRT. The outcomes of the 209 (79%) younger patients (age < 70 years old) were compared with the 54 (21%) elderly patients (age > or = 70 years old). RESULTS: Elderly patients presented with significantly greater weight loss and poorer performance status. The 2-year and 5-year survival rates were 48% and 22% for younger patients compared with 33% and 17% for older patients (P = 0.14). One specific toxicity (i.e., Grade > or = 4 pneumonitis [according to National Cancer Institute Common Toxicity Criteria]) occurred in 0% of those patients age < 70 years compared with 6% of older patients (P = 0.008). Grade 5 toxicity occurred in 1 of 209 (0.5%) patients age < 70 years compared with 3 of 54 (5.6%) older patients (P = 0.03). CONCLUSIONS: Despite having more weight loss, poorer performance status, increased pulmonary toxicity, and more deaths due to treatment, survival was not found to be significantly worse in older individuals. Fit elderly patients with LD-SCLC can receive combined-modality therapy with the expectation of relatively favorable long-term survival. Future research should focus on ways to decrease toxicity especially in the elderly.

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PubMed2005

A phase I and pharmacologic trial of two schedules of the proteasome inhibitor, PS-341 (bortezomib, velcade), in patients with advanced cancer.

PURPOSE: To define the toxicities, pharmacodynamics, and clinical activity of the proteasome inhibitor, PS-341 (bortezomib), in patients with advanced malignancies. PATIENTS AND METHODS: Twenty-eight patients (14 male and 14 female) received PS-341 twice weekly for 4 of 6 weeks (schedule I). Because toxicity necessitated dose omissions on this schedule, 16 additional patients (12 male and 4 female) received PS-341 twice weekly for 2 of every 3 weeks (schedule II). A total of 73 courses of treatment was given (median, 2; range, 1-4). Inhibition of 20S proteasome activity in peripheral blood mononuclear cells (PBMC) and accumulation of proteasome-targeted polypeptides in tumor tissue were evaluated as pharmacodynamic markers of PS-341 activity. RESULTS: The most common toxicity was thrombocytopenia, which was dose limiting at 1.7 mg/m2 (schedule I) and 1.6 mg/m2 (schedule II), respectively. Sensory neuropathy was dose-limiting in a patient in schedule I. Grade > or =3 toxicities for schedule I were constipation, fatigue, myalgia, and sensory neuropathy. Grade > or =3 toxicities for schedule II were dehydration resulting from diarrhea, nausea and vomiting, fatigue, hypoglycemia, and hypotension. The maximum tolerated dose was 1.5 mg/m2 for both schedules. Reversible dose-dependent decreases in 20S proteasome activity in PBMCs were observed, with 36% inhibition at 0.5 mg/m2, 52% at 0.9 mg/m2, and 75% at 1.25 mg/m2. Accumulation of proteasome-targeted polypeptides was detected in tumor samples after treatment with PS-341. A patient with multiple myeloma had a partial response. CONCLUSION: PS-341 given 1.5 mg/m2 twice weekly for 2 of every 3 weeks is well tolerated and should be further studied.

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PubMed2005

A phase I trial of the novel farnesyl protein transferase inhibitor, BMS-214662, in combination with paclitaxel and carboplatin in patients with advanced cancer.

PURPOSE: This phase I study was conducted to determine the toxicities, pharmacokinetics, and pharmacodynamics of BMS-214662, a farnesyl transferase inhibitor, in combination with paclitaxel and carboplatin, in patients with advanced solid tumors. EXPERIMENTAL DESIGN: Patients with solid tumors received one of six escalating dose levels of BMS-214662 infused over 1 hour given following paclitaxel and carboplatin on the first day of a 21-day cycle. Toxicities were graded by the National Cancer Institute common toxicity criteria and recorded as maximum grade per patient for each treatment cycle. Inhibition of farnesyl transferase activity in peripheral blood mononuclear cells (PBMCs) was evaluated. Accumulation of unfarnesylated HDJ-2 in PBMCs of patients was evaluated as a marker of farnesyl transferase inhibition by BMS-214662. RESULTS: Thirty patients received 141 cycles of treatment through six dose levels. Dose-limiting toxicities were neutropenia, thrombocytopenia, nausea, and vomiting. There was no pharmacokinetic interaction between BMS-214662 and paclitaxel. The maximum tolerated dose was established as BMS-214662 (160 mg/m(2)), paclitaxel (225 mg/m(2)) and carboplatin (area under the curve = 6 on day 1), every 21 days. Inhibition of HDJ-2 farnesylation in PBMCs of patients was shown. One measurable partial response was observed in a patient with taxane-resistant esophageal cancer. There was partial regression of evaluable disease in two other patients (endometrial and ovarian cancer). Stable disease (> 4 cycles) occurred in eight other patients. CONCLUSIONS: The combination of BMS-214662 with paclitaxel and carboplatin was well tolerated, with broad activity in solid tumors. There was no correlation between dose level and accumulation of unfarnesylated HDJ-2 in PBMCs nor tumor response.

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PubMed2004

Complementary and alternative medicine use by patients enrolled onto phase I clinical trials.

PURPOSE: To describe the prevalence, clinical characteristics, and pattern of use of complementary and alternative medicine (CAM) in patients enrolled onto phase I trials. PATIENTS AND METHODS: Questionnaires were administered to 108 patients with advanced malignancies enrolled onto phase I chemotherapy trials at the Mayo Clinic Comprehensive Cancer Center (Rochester, MN). CAM was classified into two modalities, pharmacologic and nonpharmacologic. Clinical and demographic data, including age, sex, and prior cancer treatment, were subsequently obtained from patient charts and examined for any correlation with CAM use, using chi2 analysis. RESULTS: One hundred two survey forms were returned. Among respondents, 88.2% (90 of 102) had used at least one CAM modality; 93.3% (84 of 90) and 53.3% (48 of 90) had used pharmacologic and nonpharmacologic CAM, respectively; and 46.7% (42 of 90) used both modalities. Vitamin and mineral preparations constituted 89.3% (75 of 84) of all pharmacologic CAM used. Intake was highest for vitamins E (48.8% [41 of 84]) and C (38.1% [32 of 84]), and 71.4% (60 of 84) of respondents took nonvitamin/mineral agents. Green tea (29.8% [25 of 84]), echinacea (13.1% [11 of 84]), and essiac (9.5% [8 of 84]) were the most popular. Prayer and spiritual practices were the most commonly used nonpharmacologic CAM, accounting for 52.1% (25 of 48). Chiropractors, the most frequently visited nontraditional medicine practitioners, were consulted by only 10% (9 of 90) of those who practiced CAM. Both CAM modalities were used more frequently by women (53.5% [23 of 43]) than men (40.4% [19 of 47]). CONCLUSION: CAM use is common among patients in phase I trials and should be ascertained by investigators, because some of the agents used may interact with investigational agents and affect adverse effects and/or efficacy.

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