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Biomedical subjects

Byron M Espina

Publications and source records attributed to Byron M Espina.

9 recordsLinked to original sources

Phase I study of antisense oligonucleotide against vascular endothelial growth factor: decrease in plasma vascular endothelial growth factor with potential clinical efficacy.

PURPOSE: Vascular endothelial growth factor antisense (VEGF-AS) is an antisense oligonucleotide that targets VEGF, inhibiting angiogenesis and tumor cell proliferation. This study established the safety, biologic effects, and pharmacokinetics of VEGF-AS in 51 patients with advanced malignancies. METHODS: VEGF-AS was administered as a 2-hour infusion daily for 5 consecutive days for only one cycle on the first four dose levels, and then administered daily for 5 days every other week for up to 4 months on subsequent levels. Pharmacokinetics, tumor response, and the effect on plasma VEGF levels were determined. RESULTS: The maximum-tolerated dose was 200 mg/m2. Dose-limiting toxicities included grade 4 fever, and pulmonary embolism in one patient each at 250 mg/m2. Mild anemia, fever, fatigue, and gastrointestinal complaints were the most common adverse events. VEGF-AS t(1/2beta) (beta-phase terminal half-life of drug concentration) was 2.25 hours (range, 1.97 to 2.95 hours). Mean plasma VEGF-A (P = .002) and VEGF-C (P = .01) levels decreased 24 hours postinfusion, with a trend towards greater decreases at higher dose levels. At the maximum-tolerated dose, five of six patients demonstrated reductions in plasma VEGF. Clinical responses included complete remission in one patient with AIDS-Kaposi's sarcoma, a mixed but dramatic response in one patient with cutaneous T-cell lymphoma, and prolongation of progression-free survival compared with that obtained on the immediate prior regimen in six patients (12%) with renal cell, bronchoalveolar, small cell lung, thyroid, and ovarian carcinomas, and chondrosarcoma, respectively. CONCLUSION: VEGF-AS was well tolerated, with biologic effects and preliminary evidence of clinical efficacy.

Adult↗

Phase I/II trial of nonpegylated liposomal doxorubicin, cyclophosphamide, vincristine, and prednisone in the treatment of newly diagnosed aggressive non-Hodgkin's lymphoma.

BACKGROUND: The toxicity and efficacy of nonpegylated liposomal doxorubicin (TLC D-99) when substituted for conventional doxorubicin in the CHOP (doxorubicin/cyclophosphamide/vincristine/prednisone) regimen were evaluated in the treatment of newly diagnosed patients with aggressive non-Hodgkin's lymphoma. Liposomal doxorubicin at doses of 40 mg/m2, 50 mg/m2, 60 mg/m2, and 80 mg/m2 was given with fixed doses of cyclophosphamide, vincristine, and prednisone. Chemotherapy cycles were repeated every 21 days. PATIENTS AND METHODS: Forty-seven patients with a median age of 55 years (range, 25-83 years) were studied. RESULTS: No dose-limiting toxicities were observed at any level. Reversible grade 3/4 neutropenia was the most common toxicity (95.8%). Most nonhematologic side effects were grade 1/2 in severity. Complete remissions were documented in 31 of 46 evaluable patients (67.4%) and partial remissions in 7 (15.2%), for an overall major response rate of 82.6%. The median duration of complete remission is > or = 27.7 months (range, 2.4 months to > or = 59.8 months). An exploratory objective was to correlate multidrug resistance-1 (MDR-1) expression with outcome. Immunohistochemistry for MDR-1-related p-glycoprotein was assessed in lymphoma tissues from 27 patients. Of the 27 lymphoma tissues studied, 8 (30%) were MDR-1 positive at diagnosis. The complete response rate was 63% in MDR-1-positive lymphomas and 74% in the MDR-1-negative cases (P = 0.66). CONCLUSION: Nonpegylated liposomal doxorubicin in combination with cyclophosphamide, vincristine, and prednisone is an active regimen for patients with newly diagnosed, aggressive non-Hodgkin's lymphoma. The regimen is relatively well tolerated, with hematologic suppression as the major toxicity. Liposomal encapsulation might evade resistance caused by MDR-1 expression.

Adult↗

Weekly docetaxel is safe and effective in the treatment of advanced-stage acquired immunodeficiency syndrome-related Kaposi sarcoma.

BACKGROUND: Intravenous paclitaxel, 100 mg/m(2), given over 3 hours every 2 weeks is associated with a response rate of 59% in patients with recurrent or refractory acquired immunodeficiency syndrome (AIDS)-related Kaposi sarcoma (KS). However, this regimen is associated with significant myelosuppression, and the inconvenience of a 3-hour infusion. Moreover, no effective therapies have been defined for use after treatment failure with this agent. A Phase II trial was conducted with weekly docetaxel in patients with advanced-stage KS to assess safety and antitumor activity. METHODS: Docetaxel was administered at a dose of 25 mg/m(2) intravenously over 15-30 minutes weekly for 8 weeks. Thereafter, if the patient experienced stable disease or better response, treatment doses were given every other week until complete disease remission, disease progression, or unacceptable toxicity occurred. RESULTS: Twelve patients were accrued-9 had > 25 mucocutaneous lesions, 1 had lymphedema, and 2 had visceral involvement. Ten patients (83%) had previous systemic chemotherapy, including 4 who received previous paclitaxel. Treatment was well tolerated, with no Grade 4 toxicity of any type. Grade 3 neutropenia occurred in 33% of patients but no patient had neutropenic fever. Five patients (42%) achieved a partial response, including 1 who had previously failed to respond to paclitaxel. The median time to disease progression was 26 months (range, 5-53 months). With a median follow-up period of 45 months, the median survival point had not been reached. CONCLUSIONS: Weekly docetaxel is safe, with reasonable antitumor activity in patients with advanced-stage, recurrent, or refractory AIDS-related KS.

Acquired Immunodeficiency Syndrome↗

Hepatitis C virus-related thrombocytopenia: clinical and laboratory characteristics compared with chronic immune thrombocytopenic purpura.

Thrombocytopenia can be a complication of hepatitis C viral (HCV) infection. However, there is little published data regarding the clinical and laboratory manifestations of HCV-related thrombocytopenia (HCV-TP) compared with adult chronic immune thrombocytopenic purpura (CITP). We reviewed the medical records for all patients evaluated for chronic thrombocytopenia by the Haematology Service between January 1996 and June 2000. All patients were screened for HCV infection at the time of initial diagnosis. Of 250 patients who fulfilled American Society of Hematology criteria for CITP, 76 (30%) were HCV seropositive. HCV-TP patients were older [mean age (+/-SD) 54.9 +/- 8 years vs. 40.3 +/- 8 years, P </= 0.001] and equally distributed between both sexes. HCV-TP patients had less severe thrombocytopenia, defined as platelet count </=10 x 10(9)/l (4% vs. 46% for CITP, P </= 0.001). However, 56 (74%) had a platelet count </=50 x 10(9)/l. Symptoms and signs of thrombocytopenia were less frequent in HCV-TP, but major bleeding was more frequent (25% vs. 10%, P = 0.0059). Serum cryoglobulins and anticardiolipin antibodies were more frequent in HCV-TP (90% and 62% respectively), but rare in CITP (7% and 15%, P </= 0.001 compared with HCV-TP). HCV infection can be associated with significant thrombocytopenia and appears to be a distinct clinical entity.

Adult↗

T-cell lymphoma in HIV-infected patients.

Linkage of AIDS and cancer registries has indicated an increase in T-cell lymphomas among individuals infected with the HIV. The characteristics of T-cell versus B-cell lymphoma in HIV-infected patients are not well described. Retrospectively, 11 cases of T-cell lymphoma were identified from the AIDS-Lymphoma Registry at the University of Southern California. These patients were compared with 418 consecutive HIV-seropositive patients with B-cell lymphoma diagnosed and treated within the same time period. T-cell lymphomas comprised 3% of all AIDS lymphomas. Pathologic types included peripheral T-cell lymphoma in 5; anaplastic large cell lymphoma in 3; and angioimmunoblastic, enteropathy type, and human T-cell lymphotropic virus-I-related adult T-cell lymphoma/leukemia in 1 case each. No differences in demographic characteristics, history of prior opportunistic infection, or immunologic characteristics were observed between T-cell and B-cell cases. Extranodal involvement of the skin (36% vs. 2%, P < 0.001) and bone marrow (45% vs. 15%, P = 0.019) was significantly more common in T-cell lymphomas. The median survival of patients with T-cell lymphomas was not significantly different from that of B-cell lymphoma patients (10.6 vs. 6.6 months, P = 0.13). T-cell lymphomas in HIV-infected patients represent a spectrum of pathologic types. T-cell lymphomas differ from B-cell cases in terms of a higher propensity for skin and bone marrow involvement. The median survival of patients with T-cell lymphoma is comparable to that of patients with B-cell AIDS-related lymphoma.

Adult↗

Treatment of AIDS related non-Hodgkin's lymphoma with combination mitoguazone dihydrochloride and low dose CHOP chemotherapy: results of a phase II study.

PURPOSE: To evaluate the response and side effects of combination therapy with low dose CHOP chemotherapy and mitoguazone dihydrochloride in patients with non-Hodgkin's lymphoma associated with the acquired immunodeficiency syndrome (AIDS-NHL). METHODS: Eighteen patients newly diagnosed with intermediate or high-grade AIDS-NHL were treated with low dose CHOP as follows: day 1, cyclophosphamide 350 mg/m(2), intravenously (IV); doxorubicin 25mg/m(2) IV; vincristine 2mg IV; and prednisone 100mg given orally on days 1 through 5. In addition, mitoguazone dihydrochloride was given at a dose of 600 mg/m(2) IV on days 1 and 15 of each 28-day treatment cycle. RESULTS: Seventeen males and one female patient were accrued. Twelve patients had high-grade pathologies while the remainder had an intermediate grade pathology (diffuse large cell). The median CD4+ lymphocyte count was 98/dl (range 1-924). Three patients (17%) reported an AIDS-defining illness prior to lymphoma diagnosis. Of 14 evaluable patients, 6 (43%) achieved a complete remission and 5 (35%) a partial remission. The median failure free and overall survival times were 6.5 and 8.4 months, respectively. Major toxicity was hematologic with grade 3 or 4 neutropenia in 72%; two patients died of neutropenic sepsis. CONCLUSIONS: Mitoguazone in combination with low dose CHOP is a safe regimen, associated with a response rate of 79% (CR 43%, PR 36%, 95% CI=49-95%). These preliminary results suggest no major improvement in terms of response over use of CHOP without mitoguazone.

Adult↗

Multicenter trial of low-dose paclitaxel in patients with advanced AIDS-related Kaposi sarcoma.

BACKGROUND: Treatment options are limited for patients with advanced acquired immunodeficiency syndrome (AIDS)-related Kaposi sarcoma (AIDS-KS) whose disease has progressed after receiving therapy with liposomal anthracyclines or combination chemotherapy with doxorubicin (Adriamycin), bleomycin, and vincristine (ABV). This study was performed to assess the safety and efficacy of a novel dose and schedule of paclitaxel in patients with AIDS-KS who failed to respond to previous systemic chemotherapy. METHODS: This was an open-label, multicenter Phase II study. Eligible patients had advanced AIDS-KS consisting of at least 25 mucocutaneous lesions, visceral disease, or lymphedema, and had failed to respond to at least one previous systemic chemotherapy regimen. Patients were treated with paclitaxel at a dose of 100 mg/m(2) given intravenously over 3 hours, every 2 weeks. Primary efficacy end points were tumor response, time to progression, time to treatment failure, and survival. Quality of life and adverse events were evaluated using the Symptom Distress Scale (SDS) and the World Health Organization Toxicity Criteria, respectively. RESULTS: One hundred and seven male patients with advanced AIDS-KS were enrolled from nine participating sites. The median entry CD4+ lymphocyte count was 41/mm(3) (range 0-1139). Previous treatment regimens included ABV in 52, liposomal daunorubicin in 49, and liposomal doxorubicin in 40 patients. Forty-one patients (38%) received two or more previous chemotherapy regimens. Protease inhibitor use during the study was reported by 82 (77%) patients overall; 47 patients (44%) were receiving a protease inhibitor before study entry. Complete or partial response was documented in 60 patients (56%). The median duration of response was 8.9 months. Major response rate was similar when comparing patients not on a protease inhibitor at the time of response (59%) with patients on a protease inhibitor at time of response (54%). However, protease inhibitor use had a significant impact on survival (P = 0.04). Grade 4 neutropenia was reported in 35% of patients; other life-threatening side effects were uncommon. Significant improvements were seen in the total quality of life scores measured by the SDS, including significant improvement in KS-related symptoms such as facial disease, tumor-associated edema, and pulmonary involvement. CONCLUSION: Paclitaxel given every 2 weeks induces major tumor regression in the majority of patients with advanced KS who failed to respond to previous systemic chemotherapy. Paclitaxel is associated with significant improvement in quality of life with acceptable toxicity and should be considered as an effective treatment option for patients with advanced KS.

Acquired Immunodeficiency Syndrome↗

Potential role of platelet FcgammaRIIA in collagen-mediated platelet activation associated with atherothrombosis.

Collagen-mediated platelet activation contributes significantly to coronary and cerebrovascular thrombus formation associated with atherosclerotic plaque destabilization. Recent clinical and laboratory observations support a potential role for the platelet Fc receptor (FcgammaRIIA) in this process. The purpose of this study was to elucidate any association between platelet Fc receptor (FcR) expression levels and both atherosclerosis risk factors (ARFs) along with collagen-dependent platelet activation. Age and gender-independent variation has been described in the expression of this receptor that is stable over time. Platelet Fc surface expression was compared between patients experiencing an acute coronary or cerebrovascular event, healthy patients with two or more ARFs, and healthy patients with fewer than two ARFs. Platelet FcR expression was significantly and stably (6-52 weeks, mean 20 weeks) increased in 101 patients with acute myocardial infarction, unstable angina, or ischemic stroke syndrome (P<0.001) and 38 healthy patients with two or more ARFs (P=0.027) compared with 109 healthy patients with fewer than two ARFs. Patients with diabetes mellitus from all groups had significantly increased platelet FcR expression over those without diabetes (P<0.0001). Platelet aggregation studies suggested a correlation between number of ARFs per patient, platelet Fc expression levels, and relative sensitivity to collagen stimulation. Platelet FcR surface expression is increased in patients with an acute coronary or cerebrovascular event, non-acutely ill patients with two or more ARFs, and in patients with diabetes mellitus. Increased platelet FcR expression may therefore contribute towards risk for atherothrombotic events.

Adult↗

Multidrug resistance (MDR-1) expression in AIDS-related lymphomas.

P-glycoprotein is a product of the multidrug resistance (MDR-1) gene. In non-Hodgkin's lymphoma, less than 20% of untreated de novo lymphomas express MDR-1 compared with approximately 50% after failure of chemotherapy. We wished to study the expression of MDR-1 in AIDS-related non-Hodgkin's lymphoma (AIDS-NHL). Tissue biopsies from 50 patients with newly diagnosed AIDS-NHL were studied by immunohistochemical analysis using C494, a monoclonal antibody specific for the MDR-1 isoform of P-gp. MDR-1 expression was correlated with patient demographics, lymphoma characteristics, response to chemotherapy, and survival. Forty-six males and four females with a median age of 38 years (range 26-63) were studied. A prior AIDS-defining opportunistic infection was reported in 35 patients (70%). The median CD4+ lymphocyte count was 69/mm(3) (range 0-920). Thirty-two patients (63%) had received prior anti-HIV therapy, including a protease inhibitor in five (10%). Pathologic types consisted of diffuse large cell in 13 (26%), immunoblastic in 13 (26%), small non-cleaved in 22 (44%), and high grade not otherwise specified in two (4%). The majority of patients (76%) had stage III/IV disease. Pre-treatment lymphoma tissues from 33 patients (66%) stained positively for MDR-1. MDR-1 positive patients had a significantly lower complete remission rate compared to MDR-1 negative patients (33 versus 65%, P=0.042). Duration of complete response was significantly longer in MDR-1 negative patients compared with MDR-1 positive patients (not reached versus 9.9 months, P=0.003). Strategies to overcome MDR-1 expression may be important for initial treatment in patients with AIDS-NHL.

ATP Binding Cassette Transporter, Subfamily B, Mem↗