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Biomedical subjects

L L Miller

Publications and source records attributed to L L Miller.

At least 37 records · Page 2Linked to original sources

Abrogation of the hematological and biological activities of the interleukin-3/granulocyte-macrophage colony-stimulating factor fusion protein PIXY321 by neutralizing anti-PIXY321 antibodies in cancer patients receiving high-dose carboplatin.

This dose-escalation study was performed to evaluate the hematologic activity, biological effects, immunogenicity, and toxicity of PIXY321 (an interleukin-3/granulocyte-macrophage colony-stimulating factor fusion protein) administered after high-dose carboplatin (CBDCA) treatment. Patients with advanced cancers received CBDCA at 800 mg/m2 intravenously on day 0 of repeated 28-day cycles. In part A of the study, patients were treated with CBDCA alone during cycle 1 and then received PIXY321 on days 1 through 18 of cycle 2 and later cycles. In part B, patients received 18 days of PIXY321 beginning on day 1 of all CBDCA cycles, including cycle 1. PIXY321 was administered subcutaneously in 2 divided doses. Total doses of 135, 250, 500, 750, and 1,000 micrograms/m2/d were administered to successive cohorts of 3 to 6 patients in part A. In part B, patient groups received PIXY321 doses of 750, 1,000, and 1,250 micrograms/m2/d. The hematologic effects of PIXY321 were assessed in the first 2 cycles of therapy. Anti-PIXY321 antibody formation was assessed by enzyme-linked immunosorbent assay (ELISA) and neutralization assay. Of the 49 patients enrolled, 31 were fully evaluable for hematologic efficacy. When comparing the first B cycle (cycle B-1; with PIXY321) with the first A cycle (cycle A-1; without PIXY321), the fusion protein had no significant effect on platelet nadirs or duration of platelets less than 20,000/microL but was able to speed the time of recovery of platelet counts to 100,000/microL (15 v 20 days; P =.01). Significant improvements in neutrophil nadir and duration of ANC less than 500 were observed in cycles A-2 and B-1 (with PIXY321) as compared with cycle A-1 (without PIXY321). Initial PIXY321 prophylaxis (cycle A-2 and cycle B-1), enhanced the recovery of ANC to greater than 1,500/microL by an average of at least 8 days as compared with cycle A-1 (without PIXY321; P </=.004). However, positive PIXY321 hematologic effects were lost in the second course of PIXY321 among patients treated in part B. ELISA analysis showed that 92% of patients had developed neutralizing anti-PIXY321 antibodies by the completion of 2 PIXY321-containing cycles. The incidental action of PIXY321 to depress serum cholesterol levels was also abrogated during cycle B-2. We conclude that PIXY321 was active in speeding hematologic recovery but that neutralizing anti-PIXY321 antibody formation suppressed the hematologic and biochemical effects by the second cycle of PIXY321 administration. The immunogenicity of this fusion protein provides a cautionary warning that clinical development of bioengineered human molecules requires thorough testing for immune neutralization.

Adult↗

A multicenter, phase II trial of weekly irinotecan (CPT-11) in patients with previously treated colorectal carcinoma.

BACKGROUND: This multicenter, Phase II trial was performed to evaluate the antitumor activity and toxicity of irinotecan (CPT-11) in patients with metastatic colorectal carcinoma that had recurred or progressed after 5-fluorouracil (5-FU)-based chemotherapy. METHODS: CPT-11 was given as a 90-minute intravenous infusion in repeated 6-week (42-day) courses comprising weekly treatment for 4 consecutive weeks followed by a 2-week rest. Tumor measurements were obtained after every second course of therapy. Toxicity was assessed weekly using the National Cancer Institute Common Toxicity Criteria. RESULTS: A total of 166 patients were entered into the trial. The first 64 patients received a starting dose of 125 mg/m2. An additional 102 patients were enrolled at a starting dose of 100 mg/m2 to determine whether a reduction in the starting dose would result in lower toxicity without sacrificing efficacy. Objective responses to CPT-11 were observed in 18 patients (1 complete response and 17 partial responses) (response rate [RR] = 10.8%; 95% confidence interval [CI], 6.1-15.6%). An additional 67 patients (40.4%) had stable disease as their best response. At the 125 mg/m2 starting dose, the RR was 14.1% (9 of 64 patients; 95% CI, 5.5-22.6%). Among patients given a starting dose of 100 mg/m2, the RR was 8.8% (9 of 102 patients; 95% CI, 3.3-14.3%). The overall median survival was 9.9 months (range, 0.3-36.8 months). The most frequently observed Grade 3/4 toxicities were gastrointestinal events (i.e., diarrhea [27.1%], nausea [15.1%], emesis [9.6%], abdominal cramping [22.2%], and neutropenia [19.9%]). There were no significant differences in the frequencies of Grade 3/4 toxicities between the 125 mg/m2 and 100 mg/m2 starting dose levels except for Grade 3/4 emesis (21.9% vs. 2%; P < 0.001). Patients age > or = 65 years were twice as likely (38.6% vs. 18.8%; P < 0.008) to develop Grade 3/4 diarrhea compared with younger patients when all courses of therapy were evaluated. However, older age did not significantly predict for a higher incidence of first-course diarrhea (25.0% vs. 14.7%; P = 0.106). CONCLUSIONS: CPT-11 can induce tumor regression in patients with metastatic colorectal carcinoma that has progressed during or shortly after 5-FU-based chemotherapy. Gastrointestinal events and neutropenia were the most common serious toxicities. Given the trend toward a higher response rate without substantially greater toxicity, 125 mg/m2 has been selected as the preferred starting dose for further studies. Careful attention to appropriate CPT-11 dose modification and early intervention with loperamide may be especially important in elderly patients.

Adult↗

Treatment with tumor necrosis factor-alpha and granulocyte-macrophage colony-stimulating factor increases epidermal Langerhans' cell numbers in cancer patients.

Dendritic cells (DCs) initiate primary and stimulate secondary T-cell responses. We conducted a phase I trial of tumor necrosis factor (TNF-alpha) and granulocyte-macrophage colony-stimulating factor (GM-CSF) in patients with cancer to increase DCs in peripheral blood or skin based on in vitro data that showed that CD34(+) hematopoietic precursors require these cytokines to mature into functional antigen-presenting DCs. Eleven patients were treated for 7 days with GM-CSF, 125 microg/m(2) twice daily as subcutaneous injections, and TNF-alpha as a continuous infusion at dose levels of 25, 50, or 100 microg/m(2)/day. The maximum tolerated dose of TNF-alpha was 50 microg/m(2)/day with this dose of GM-CSF; dose-limiting toxicities occurred in both patients treated with 100 microg/m(2)/day. One became thrombocytopenic and the other had transient confusion. Epidermal Langerhans' cells were quantitated by S100 staining of skin biopsies and DC precursors in peripheral blood by colony-forming unit dendritic (CFU-dendritic) assays. S100-positive cells in the epidermis doubled after treatment (2.55 S100(+) cells/high-power field before treatment to 6.05 after treatment, p = 0.029). CFU-dendritic in peripheral blood increased after treatment in 3 colorectal cancer patients but not in 3 patients with melanoma. CD11c(+) or CD123(+), HLA-DR(bright), lineage-negative dendritic cell precursors were not increased in peripheral blood mononuclear cells. This trial demonstrates that treatment with TNF-alpha and GM-CSF can increase the number of DCs in the skin and the number of dendritic cell precursors in the blood of some patients with cancer. This approach may increase the efficacy of vaccination to tumor antigens in cancer patients.

Adult↗

Epilepsy and seizure occurrence in a population-based sample of Virginian twins and their families.

Epilepsy and seizure occurrence was assessed in a large, population-based sample of Virginian twins and their families. Medical history information on twins and their relatives was collected by questionnaire and used to estimate prevalence of seizures and epilepsy for this sample. Health history information was available on 16,634 twins and their families. Lifetime prevalence of a history of seizures ranged from < 1 to 5%. Concordance rates were larger in monozygotic (MZ) than dizygotic (DZ) pairs overall, however, significant differences between the zygosities were only noted for Caucasian twins. To facilitate interpretation of results, the sample was partitioned into two age groups: 16-35 years and > 35 years of age. In the first age category of twins, significant differences were observed for the following seizure types; epilepsy (0.30 and 0.13, p <0.03), febrile seizures (0.39 and 0.12, p <0.001), and other convulsions/seizures (0.28 and 0.01, p < 0.001). While for twins in the second age category, only the comparison for febrile seizures (0.42 and 0.14, p < 0.001) resulted in a significant difference between zygosities. A family history of seizures was reported in 215 (35.1%) of the 613 seizure positive probands. Increased risk of seizures (1.88-4.64) among relatives of affected versus unaffected individuals was also observed.

Adolescent↗

Phase I and pharmacokinetic trial of oral irinotecan administered daily for 5 days every 3 weeks in patients with solid tumors.

PURPOSE: We conducted a phase I dose-escalation trial of orally administered irinotecan (CPT-11) to characterize the maximum-tolerated dose (MTD), dose-limiting toxicities (DLTs), pharmacokinetic profile, and antitumor effects in patients with refractory malignancies. PATIENTS AND METHODS: CPT-11 solution for intravenous (IV) use was mixed with CranGrape juice (Ocean Spray, Lakeville-Middleboro, MA) and administered orally once per day for 5 days every 3 weeks to 28 patients. Starting dosages ranged from 20 to 100 mg/m2/d. RESULTS: Grade 4 delayed diarrhea was the DLT at the 80 mg/m2/d dosage in patients younger than 65 years of age and at the 66 mg/m2/d dosage in patients 65 or older. The other most clinically significant toxicity of oral CPT-11 was neutropenia. A linear relationship was found between dose, peak plasma concentration, and area under the concentration-time curve (AUC) for both CPT-11 and SN-38 lactone, implying no saturation in the conversion of irinotecan to SN-38. The mean metabolic ratio ([AUC(SN-38 total) + AUC(SN-38G total)]/AUC(CPT-11 total)) was 0.7 to 0.8, which suggests that oral dosing results in presystemic conversion of CPT-11 to SN-38. An average of 72% of SN-38 was maintained in the lactone form during the first 24 hours after drug administration. One patient with previously treated colorectal cancer and liver metastases who received oral CPT-11 at the 80 mg/m2/d dosage achieved a confirmed partial response. CONCLUSION: The MTD and recommended phase II dosage for oral CPT-11 is 66 mg/m2/d in patients younger than 65 years of age and 50 mg/m2/d in patients 65 or older, administered daily for 5 days every 3 weeks. The DLT of diarrhea is similar to that observed with IV administration of CPT-11. The biologic activity and favorable pharmacokinetic characteristics make oral administration of CPT-11 an attractive option for further clinical development.

Administration, Oral↗

Irinotecan therapy in adults with recurrent or progressive malignant glioma.

PURPOSE: To determine the activity, toxicity, and pharmacokinetics of irinotecan (CPT-11, Camptosar; Pharmacia & Upjohn, Kalamazoo, MI) in the treatment of adults with progressive, persistent, or recurrent malignant glioma. PATIENTS AND METHODS: Patients with progressive or recurrent malignant gliomas were enrolled onto this study between October 1996 and August 1997. CPT-11 was given as a 90-minute intravenous (i.v.) infusion at a dose of 125 mg/m2 once weekly for 4 weeks followed by a 2-week rest, which comprised one course. Plasma concentrations of CPT-11 and its metabolites, SN-38 and SN-38 glucuronide (SN-38G), were determined in a subset of patients. RESULTS: All 60 patients who enrolled (36 males and 24 females) were treated with CPT-11 and all were assessable for toxicity, response, and survival. Pharmacokinetic data were available in 32 patients. Nine patients (15%; 95% confidence interval, 6% to 24%) had a confirmed partial response, and 33 patients (55%) achieved stable disease lasting more than two courses (12 weeks). Toxicity observed during the study was limited to infrequent neutropenia, nausea, vomiting, and diarrhea. CPT-11, SN-38, and SN-38G area under the plasma concentration-time curves through infinite time values in these patients were approximately 40%, 25%, and 25%, respectively, of those determined previously in patients with metastatic colorectal cancer not receiving antiepileptics or chronic dexamethasone treatment. CONCLUSION: Response results document that CPT-11, given with a standard starting dose and treatment schedule, has activity in patients with recurrent malignant glioma. However, the low incidence of severe toxicity and low plasma concentrations of CPT-11 and SN-38 achieved in this patient population suggest that concurrent treatment with anticonvulsants and dexamethasone enhances drug clearance.

Adult↗

Phase II study of irinotecan plus cisplatin in patients with advanced non-small-cell lung cancer.

PURPOSE: To evaluate the antitumor efficacy and safety of a combination of irinotecan (CPT-11) and cisplatin in patients with inoperable non-small-cell lung cancer (NSCLC). A secondary objective was to characterize the pharmacokinetics and pharmacodynamics of CPT-11 and its active metabolite, SN-38. PATIENTS AND METHODS: Patients with stage IIIB or IV NSCLC were treated with repeated 4-week courses comprising CPT-11 (60 mg/m(2)) administered on days 1, 8, and 15, and a single dose of cisplatin (80 mg/m(2)) after CPT-11 administration on day 1. RESULTS: Fifty-two patients were enrolled, including 33 men and 19 women. The median age was 61 years (range, 29 to 79 years). Southwest Oncology Group performance status was 0 in 12 patients, 1 in 32 patients, and 2 in eight patients. Eleven and 41 patients had stage IIIB and IV disease, respectively. Objective responses occurred in 28.8% of patients (15 of 52; 95% confidence interval, 16.5% to 41.2%). The median survival duration was 9.9 months (range, 1.6 to 30.8 months). The 1-year survival rate was 37%. Grade 3/4 adverse events consisted primarily of nausea (32. 7% ) or vomiting (13.5%), late-onset diarrhea (17.3%), and neutropenia (46.1%). The study design led to preferential modification of CPT-11 doses, resulting in CPT-11 dose attenuations to < or = 40 mg/m(2) in the majority of patients (31 of 52; 60%), whereas dose reductions of cisplatin were uncommon. CPT-11 pharmacokinetic parameters were comparable to those reported previously in single-agent studies. CONCLUSION: CPT-11/cisplatin is an active combination regimen with manageable toxicity in the therapy of stage IIIB/IV NSCLC. Future studies should be designed with schedules and dose modification provisions that avoid unnecessary CPT-11 dose reductions to exploit more directly the therapeutic synergy of these agents.

Adult↗

Caries-preventive effects of sodium and amine fluoride dentifrices.

PURPOSE: To determine the comparative effects of sodium (NaF) and amine fluoride dentifrices, as well as the effect of different silica abrasives used in NaF dentifrices, on caries formation in rats. MATERIALS AND METHODS: Harlan Sprague Dawley mixed sex, weanling, littermate rats were fed a cariogenic diet and inoculated with S. sobrinus strain 6715 to induce caries formation. The dentifrices evaluated contained 0.31% NaF with precipitated silica I as the abrasive system; 0.31% NaF with sodium bicarbonate and hydrated silica; placebo; amine fluoride (0.14%) containing silica (Elmex); 0.31% NaF with precipitated silica II (Sensodyne F); and 0.31% NaF with hydrated silica. Dentifrice slurries were administered 7 days per week for 3 weeks at which time the animals were euthanized and the hemijaws removed, coded and stained with a murexide solution. The recovery of S. sobrinus after the 3-week study clearly showed that all of the six groups were infected with S. sobrinus. The Keyes scoring method was then used to assess the caries formation within the six groups. RESULTS: Caries scores showed that all five experimental fluoride dentifrices were equally efficacious statistically in reducing caries formation when compared to the placebo with reductions ranging from 26 to 43%.

Amines↗

Preventing dental calculus formation in lemurs (Lemur catta, Eulemur fulvus collaris) and baboons (Papio cynocephalus).

The prevention of calculus accumulation in exotic animals is a relatively unexplored topic. A 6-mo study in ring-tailed lemurs (Lemur catta) and collared lemurs (Eulemur fulvus collaris) and two studies in baboons (Papio cynocephalus) (7.5 wks and 6.5 mo) tested the benefits of a primate diet coated with 0.6% sodium hexametaphosphate (HMP) in controlling calculus in these species using a sequential crossover design. The control regimen was an identical, but non-HMP-coated, dry primate chow. At study initiation, the primates were given a thorough dental prophylaxis and provided with the control diet or experimental diet. At the conclusion of the test period, the animals were anesthetized and examined for clinical calculus independently by two examiners. The animals were then given another dental prophylaxis, provided the alternate ration, and the foregoing procedures were repeated. When the animals were provided the HMP-coated diet, significant reductions in calculus formation of 48-62% were observed in the lemurs and the baboons. No clinically significant changes were observed in body weights or in blood chemistry values as a result of ingestion of the HMP-coated regimen.

Animal Feed↗

Univariate genetic analyses of epilepsy and seizures in a population-based twin study: the Virginia Twin Registry.

The purpose of this study was to examine the roles of genetic and environmental factors in the etiology of epilepsy and seizures in twins ascertained from the Virginia Twin Registry. Health history information on twins was collected by questionnaire. Concordance rates were calculated and used to estimate degree of concordance for seizure types in monozygotic (MZ) and dizygotic (DZ) twin pairs. Univariate twin analyses were performed for each epilepsy and seizure type to determine models which best explained observed variation. Health history information concerning epilepsy and febrile seizure occurrences was provided by members of 8,655 twin pairs; 6,684 of these supplied additional information reporting absence, complex partial, tonic-clonic, and unspecified seizures. Models including additive genetic and unique environmental factors best explained febrile seizures, epilepsy, complex partial seizures, and unspecified seizures. For complex partial seizures, however, the contributions of genetic and environmental effects did not vary across gender. These results show that, under univariate analysis methods, genetic factors played an important role in the expression of seizures in epilepsy, febrile seizures, unspecified seizures, and complex partial seizures. Additional support for these findings was provided by the concordance results for all categories except male twins reporting complex partial seizure occurrence. However, environmental influences still remained an important factor in seizure expression in these specific categories.

Adolescent↗

Phase II study of adozelesin in untreated metastatic breast cancer.

Adozelesin is the first of a class of DNA-sequence-selective alkylating agents, the cyclopropa(c)pyrrolo(3,2-e)indol-4(5H)-ones (CPls), that have been shown to have of potent inhibitory properties of DNA synthesis. Based on preliminary data from phase I studies showing clinical activity in patients with breast cancer, we initiated a multicenter phase II study in untreated metastatic breast carcinoma. Adozelesin was administered at a starting dose of 150 microg/m2 as a single 10 min infusion per course, repeated every 4 weeks, for up to 1 year of treatment. It was planned that at least 25 patients should be accrued but the trial was stopped early because of slow accrual and lack of efficacy as demonstrated by the infrequency of objective responses. Seventeen patients were enrolled in this study, only 14 were evaluable, the following responses were observed: one partial response (7%), three stable diseases (22%) and 10 progressive diseases (71%). Myelosuppression was the most frequent adverse event; one patient died of pulmonary complications. We conclude that adozelesin has marginal efficacy in the treatment of metastatic breast cancer at the dosage and schedule used in this study.

Adult↗

Phase I clinical and pharmacologic study of weekly cisplatin combined with weekly irinotecan in patients with advanced solid tumors.

PURPOSE: In vitro synergy between cisplatin and irinotecan (CPT-11) has been reported. We designed a combination schedule of these agents to maximize the potential for synergistic interaction. PATIENTS AND METHODS: To maximize the opportunity for synergy, we divided the cisplatin into four consecutive weekly treatments, followed by a 2-week rest. Each dose of cisplatin was immediately followed by a dose of irinotecan. The dose of cisplatin was fixed at 30 mg/m2/wk. The initial irinotecan dose was 50 mg/m2/wk and this was escalated by 30% increments in successive cohorts of three to six patients to establish the maximum-tolerated dose (MTD). Pharmacokinetics of irinotecan and its metabolites, SN-38 and SN-38 glucuronide (SN-38G), were analyzed. RESULTS: Of 35 patients with solid tumors enrolled onto this trial, 30 were assessable for toxicity and response. The MTD for this regimen was 30 mg/m2/wk of cisplatin plus 50 mg/m2/wk of irinotecan in previously treated patients and 30 mg/m2/wk of cisplatin plus 65 mg/m2/wk of irinotecan in chemotherapy-naive patients. Neutropenia was the dose-limiting toxicity (DLT) encountered in this trial. Diarrhea was infrequent and rarely dose-limiting. Seven of 30 assessable patients achieved a partial response. No alteration in irinotecan, SN-38, or SN-38G pharmacokinetics resulted from the administration of cisplatin with irinotecan. CONCLUSION: The administration of cisplatin and irinotecan on this weekly schedule provides a practical and well-tolerated regimen that has the potential to maximize any clinical synergy between the two agents. Evidence of substantial clinical activity was seen in this phase I study.

Adult↗

Evidence for a genetic predisposition for status epilepticus.

The role of genetic factors in determining risk for status epilepticus (SE) was examined in twins identified using the population-based Virginia Twin Registry. Concordance rates for SE were 0.38 for monozygotic (MZ) and 0.00 for dizygotic (DZ) twins, with the rate in MZs being significantly increased over DZs. The prevalence of SE in MZ co-twins of affected individuals was as high as 0.55. Clinical presentation of SE was evaluated, and no association was found between occurrence of SE and age at onset or seizure etiology. Genetic factors contribute to risk for SE.

Disease Susceptibility↗

Alternative dosing schedules for irinotecan.

Most of the clinical experience with irinotecan (CPT-11 [Camptosar]) has been with either a weekly or an every-3-week schedule. Recent phase I trials have explored new routes and schedules of administration. One approach attempts to maximize dose frequency and intensity by giving irinotecan every 2 weeks. A phase I trial of this approach is now complete and has led to a phase II trial in patients with recurrent colorectal cancer. Data suggest that smaller doses of a topoisomerase I inhibitor administered repeatedly may result in greater antitumor activity than large doses administered intermittently. A phase I trial has been performed in adults in which irinotecan was administered daily for 5 consecutive days, followed by 2 days off, for 2 weeks out of 3. Similar trials are under way in children. Oral administration, another strategy that has undergone phase I testing, has several theoretical advantages:(1) The acidic pH of the stomach favors maintenance of irinotecan in the active lactone ring form. (2) Irinotecan is more rapidly and extensively converted to SN-38 by tissue carboxylesterases found in high concentrations in the gut and liver. (3) Low doses can be delivered over a protracted period. (4) The oral route enhances patient convenience. These alternative dosing schedules may facilitate integration of irinotecan into combination chemotherapy and combined-modality treatment regimens.

Adult↗

Elevated soluble interleukin 2 receptor levels found among kidney transplant recipients.

Although previous studies have not demonstrated a clear correlation between interleukin (IL) 2 receptor levels and immunological events after transplantation, many still suggest that these levels have clinical utility. A total of 759 serial measurements of both IL-2R and creatinine were compared over time and correlated with rejection episodes, clinical course, and immunosuppression. The profiles for the 40 patients showed several patterns, including correlation with changes in creatinine levels or with renal dysfunction, peaks in the absence of clinical findings, and discordant IL-2R and creatinine levels. Wide baseline variations in IL-2R levels confounded comparison of mean values and definition of a statistically significant rise. While tending to correlate with immunological events, elevations in IL-2R also occurred in clinically normal patients. IL-2R appears to lack specificity for immunological events. Thus, we conclude that IL-2R measurement does not have clinical diagnostic utility for monitoring renal transplant recipients.

Cadaver↗

Granulocyte colony-stimulating factor in severe chemotherapy-induced afebrile neutropenia.

BACKGROUND: Randomized trials of colony-stimulating factors in febrile patients with neutropenia after chemotherapy have not consistently shown clinical benefit. Nevertheless, the use of colony-stimulating factors to treat patients with chemotherapy-induced neutropenia is widespread. METHODS: We performed a randomized, double-blind, placebo-controlled trial of granulocyte colony-stimulating factor (G-CSF) in afebrile outpatients with severe chemotherapy-induced neutropenia. We measured the number of days of neutropenia, rate of hospitalization, number of days in the hospital, number of days the patient received parenteral antibiotics, and number of culture-positive infections. RESULTS: We randomly assigned 138 patients to receive G-CSF (n=71) or placebo (n=67). The median time to an absolute neutrophil count of at least 500 per cubic millimeter was significantly shorter for patients who received G-CSF (two days, vs. four days for the patients given placebo). However, there was no effect on the rate of hospitalization, number of days in the hospital, duration of treatment with parenteral antibiotics, or number of culture-positive infections. CONCLUSIONS: Routine therapeutic application of G-CSF in afebrile patients with severe neutropenia can reduce the duration of neutropenia, but this does not appear to provide practical clinical benefit.

Adult↗