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P McLaughlin

Publications and source records attributed to P McLaughlin.

At least 55 records · Page 3Linked to original sources
PubMed2000

Safety of fludarabine, mitoxantrone, and dexamethasone combined with rituximab in the treatment of stage IV indolent lymphoma.

Rituximab (Rituxan; Genentech, Inc, South San Francisco, CA and IDEC Pharmaceutical Corporation, San Diego, CA) is an effective agent for the treatment of CD20-positive B-cell lymphomas. Because its toxicities are minimal and do not overlap with the toxicities of standard chemotherapy, it is an appealing agent to use in combination with chemotherapy. Moreover, there is evidence for synergy between rituximab and some chemotherapeutic agents. The combination of fludarabine/ mitoxantrone/dexamethasone (FND) has been a well-tolerated and effective regimen for the treatment of indolent lymphomas. When given together with prophylaxis for Pneumocystis carinii, infectious complications with FND have been modest. We report on preliminary safety data using FND in conjunction with rituximab, along with maintenance alpha interferon. Toxicity has been modest. The concurrent use of rituximab with FND modestly increases neutropenia, but has not resulted in any change in the pattern of infectious or other toxicity that occurs with FND alone.

Antibodies, Monoclonal↗
PubMed1999

ASHAP: a regimen for cytoreduction of refractory or recurrent Hodgkin's disease.

Patients with Hodgkin's disease, which is either refractory or recurs after frontline chemotherapy with MOPP (mechlorethamine, vincristine, procarbazine, and prednisone), ABVD (doxorubicin, bleomycin, vinblastine, and dacarbazine), or both regimens, generally have a poor prognosis. High-dose chemotherapy with autologous marrow or stem cell rescue (ABMT) is now a widely used salvage strategy in these patients. In this study, our objective was to determine the response rate to ASHAP (Adriamycin = doxorubicin, Solumedrol = methylprednisolone, High-dose Ara-C = cytosine arabinoside, and Platinum = cisplatinum), in a group of patients with Hodgkin's disease with such poor risk characteristics. The treatment was intended as a brief tumor reducing program before ABMT. Fifty-six patients with diagnosed relapsed or primary refractory Hodgkin's disease underwent this treatment. The program consisted of the administration of two cycles of ASHAP chemotherapy (doxorubicin 10 mg/m2/d intravenous (IV) continuous infusion (CI) over 24 hours, days 1 to 4; methylprednisolone 500 mg/d IV over 15 minutes daily for 5 days; cisplatinum 25 mg/m2/d IV CI over 24 hours, days 1 to 4; cytosine arabinoside 1.5 g/m2/d IV over 2 hours on day 5). After two courses of ASHAP the patients were evaluated for response, including a gallium scan test. Patients with progressive disease were taken off the study. Those with responding or stable disease received a third course of ASHAP, followed by consolidative treatment with ABMT. There were 19 complete responses (34% CR), 20 partial responses (36% PR), and 17 treatment failures, including 8 with minor responses and 9 with disease progression. Thus, in total there were 39 responses out of 56 patients (CR + PR = 70%). Myelosuppression was the main toxicity. There were no deaths due to toxicity. At this time, 23 patients are alive. There were 31 deaths due to disease progression and 2 due to other causes. The initial response to ASHAP before subsequent ABMT consolidation treatment correlated with survival. All 17 patients in whom ASHAP failed to achieve a response have died. The presence of B symptoms at relapse, and a duration of response to the last regimen of </=6 months, predicted a poor response to ASHAP. A short program of treatment with ASHAP is an effective tumor debulking approach in patients previously treated with both or either ABVD and MOPP, before ABMT.

Adolescent↗
PubMed1999

Correlation of bcl-2 rearrangement with clinical characteristics and outcome in indolent follicular lymphoma.

The t(14;18) translocation, which involves the bcl-2 oncogene, occurs in follicular lymphomas (FL) at two common sites: the major breakpoint region (MBR) and the minor cluster region (mcr). The biological and clinical significance of these breakpoints is unknown. The bcl-2 breakpoint site was determined in 247 previously untreated patients (49% men; median age 52 years) with indolent FL (155 grade I, 83 grade II, and 8 grade III) to correlate it with pretreatment characteristics, response, and outcome. The bcl-2 breakpoint site was determined by a polymerase chain reaction method of peripheral blood (all cases), bone marrows (149 cases), and fresh lymph node biopsy specimens (68 cases). The breakpoint site occurred at MBR in 175 cases (71%) and at mcr in 27 (11%). In 45 cases (18%), no breakpoint was detected (germline). No significant relationship was found between the rearrangements and the expression of BLC-2 and BAX proteins. Patients' germline for MBR and mcr tended to present more frequently with stage IV disease and higher beta2-microglobulin (beta2M) levels, whereas mcr-rearranged patients presented more frequently with early stage and normal beta2M. The complete response rate of germline patients was significantly lower than that of MBR and mcr patients. An estimated 3-year failure-free survival (FFS) for mcr, MBR, and germline cases was 95%, 76%, and 57%, respectively (P <.001). The bcl-2 breakpoint site was independent of serum beta2M and lactate dehydrogenase in its correlation with FFS. In conclusion, the bcl-2 rearrangement site is an important prognostic factor in indolent FL, useful to identify patients who may require different treatment.

Adolescent↗
PubMed1999

Follicular large cell lymphoma: an aggressive lymphoma that often presents with favorable prognostic features.

It is debated whether follicular large cell lymphoma (FLCL) has a clinical behavior that is distinct from indolent follicular lymphomas, and whether there is a subset of patients who can be potentially cured. We report here our experience with 100 FLCL patients treated at our institution since 1984 with three successive programs. We evaluated the predictive value of pretreatment clinical features, including two risk models, the Tumor Score System and the International Prognostic Index (IPI). With a median follow-up of 67 months, the 5-year survival is 72% and the failure-free survival (FFS) is 67%, with a possible plateau in the FFS curve, particularly for patients with stage I-III disease. Features associated with shorter survival included age >/=60, elevated lactic dehydrogenase (LDH) or beta-2-microglobulin (beta2M), advanced stage, and bone marrow involvement. Stage III patients had significantly better survival than stage IV patients (P <.05). By the IPI and Tumor Score System, 80% of the patients were in the lower risk groups; both systems stratified patients into prognostic groups. Patients with FLCL have clinical features and response to treatment similar to that reported for diffuse large cell lymphoma. Prognostic risk systems for aggressive lymphomas are useful for FLCL. A meaningful fraction of patients may possibly be cured when treated as aggressive lymphomas.

Adult↗
PubMed1999

Dynamic magnetic resonance imaging of the female pelvis: radio-anatomy and pathologic applications. Preliminary results.

Dynamic MRI of the pelvis was performed in 16 young nulliparous, normally continent women. The examinations were performed in the dorsal decubitus position. Using Turbo-Flash scans (acquisition time: 2.1 sec), sagittal images were obtained at rest and with maximal pelvic straining. The sacral promontory-subpubic (PSP) and the subpubic-subsacral axes (SPSS) measured respectively 80.5 degrees and 30 degrees in relation to the horizontal plane, without a statistically significant difference between rest and straining. A marked deformation of the posterior wall of the bladder was observed in 13 cases and the bladder neck was frontally deformed in 10 cases. With straining, the base of the bladder did not descend beyond 15 mm below the SPSS, and the cervix stayed at least 14 mm above the SPSS. These were established as the normal criteria for pelvic assessment. 20 multiparous patients (mean age 65 years), referred for urinary stress incontinence and/or prolapse, were investigated using the criteria previously established. The PSP, SPSS, and vaginal angle measured 80.95 degrees, 30.57 degrees, and 69.69 degrees respectively in relation to the horizontal. No statistically significant difference was detected between straining and rest conditions. The angle of the uterus in relation to the horizontal was 57.36 degrees at rest and 65.90 degrees in straining with a difference that was statistically significant. In six patients, the base of the bladder descended more than 1.5 cm while straining and in seven patients the cervix descended at least 1.4 cm below the SPSS while straining, both statistically significant differences. Overall, between our control and study populations, there were no significant differences between PSP and SPSS measured on straining and at rest. However, differences were detected in the vaginal angle, bladder-base position, and cervical position. These results suggest the potential substitution of MRI for colpocystography.

Aged↗
PubMed1999

Phase II study of paclitaxel in combination with mitoxantrone and ifosfamide/mesna for patients with relapsed or refractory non-Hodgkin's lymphoma after failure to cytarabine/cisplatin combination.

PURPOSE: Evaluate response, duration of response, and toxicity of paclitaxel in combination with other drugs known to be effective in non-Hodgkin's lymphoma (NHL). METHODS: Thirty-eight patients with relapsed/refractory NHL who had been exposed to doxorubicin as well as the cytarabine-cisplatin combinations received Mesna 1.33 gm/M2/D daily days 1, 2, 3 i.v. over 1 hour; ifosfamide 1.33 gm/M2/D daily days 1, 2, 3 i.v. over 1 hour (same bag); Novantrone 8 mg/M2/D i.v. day 1; and Taxol 27.5 mg/M2/D daily days 1, 2, 3, 4 by continuous 24-hour intravenous infusion. Premedication for Taxol included dexamethasone, diphenhydramine, and cimetidine on day 1. RESULTS: Of 35 evaluable patients, 9 (26%) achieved a complete response and 7 (20%) a partial response for a total response rate of 46%. The median failure-free and overall survival times were 2 and 10 months, respectively. Major toxicity was hematologic with a median absolute neutrophil nadir of 196/mm3. Only 10% of the cycles were associated with a grade 3-4 infection. CONCLUSION: MINT is an active and safe regimen for relapsed/refractory NHL that have failed both an Adriamycin-containing regimen and a cytarabine/cisplatin-containing regimen.

Adult↗
PubMed1999

Interleukin-10 levels are often elevated in serum of adults with Hodgkin's disease and are associated with inferior failure-free survival.

BACKGROUND: Interleukin-10 (IL-10) is a pleiotropic cytokine that protects B- or T-lymphocytes and hemopoietic progenitors from apoptosis induced by doxorubicin, glucocorticoids, or deprivation of growth factors. IL-10 is also immunosupressive, and tumor cells secreting IL-10 can grow in syngeneic or allogeneic hosts, and can inhibit the generation of tumor-specific cytotoxic T cells. Hodgkin-Reed-Sternberg cells are derived from follicular center B cells and they may be latently infected by EBV. When this occurs they often express IL-10. Based on these considerations we investigated the relationship between pretreatment serum IL-10 levels and failure-free survival (FFS) in Hodgkin's disease (HD). PATIENTS AND METHODS: Untreated patients, older than 16 years, with biopsy-proven HD, were included if treated with ABVD or equivalent regimens, and if pretreatment serum was available. IL-10 levels were determined with a capture enzyme-linked immunoassay specific for cellular IL-10. RESULTS: Among healthy adult volunteers serum IL-10 levels ranged from 4.8-9.8 pg/ml (mean 7.1, standard deviation 1.5 pg/ml). Therefore levels > or = 10 pg/ml were considered elevated. We identified 101 patients with available serum. Their median age was 32 years, and 60% had B-symptoms. Ann Arbor stage was I in 4, II in 21, III in 35, and IV in 41 patients. Histology was nodular sclerosis in 74, mixed cellularity in 12, lymphocyte predominance in six, lymphocyte depletion in one, and unclassified in eight patients. Pretreatment serum IL-10 levels were elevated in 51 patients, and were higher in those with serum albumin < 3.5 g/dl, B symptoms, serum beta 2-microglobulin > or = 2.5 mg/l, anemia, and AAS III or IV. After a median follow-up of 32 months for survivors, 20 patients have progressed, and the three-year FFS of those with high vs. normal serum IL-10 was 60% +/- 9 vs. 91 +/- 9% (50% vs. 50% of the population; P = 0.004 by log-rank). Among patients with Ann Arbor stage III or IV the three-year FFS for those with high vs. normal serum IL-10 (58 vs. 42% of the population) was 57 +/- 9% vs. 92 +/- 6% (P = 0.008 by log-rank). Multivariate analysis using Cox's proportional hazards model confirmed that IL-10 was an independent variable associated with inferior FFS in this population. CONCLUSIONS: Elevation of serum IL-10 levels is frequent and is associated with inferior FFS in adults with ABVD-treated HD. This observation should be verified in other patient populations. In addition, the source and the role of IL-10 in the biology of HD should be further investigated.

Adolescent↗
PubMed1999

Tamoxifen-induced thrombocytopenia.

Thrombocytopenia (platelet count < 100,000/microl) is a rare side effect of tamoxifen (Nolvadex). We report a case of thrombocytopenia that developed 6 months after tamoxifen was given as an adjuvant treatment for breast cancer. The patient received no concurrent cytotoxic chemotherapy or radiation therapy. The thrombocytopenia resolved after the tamoxifen was stopped, reappeared promptly when the tamoxifen was restarted, and resolved again after the second withdrawal, at which time anastrozole (Arimidex) was substituted for the tamoxifen. The patient's platelet count remained normal for more than 6 months thereafter.

Antineoplastic Agents, Hormonal↗
PubMed1999

Treatment of follicular and other indolent lymphomas.

The understanding of specific lymphoma entities continues to evolve. This is perhaps most clearly illustrated by developments concerning gastric lymphomas of mucosa-associated lymphoid tissue (MALT) origin, ranging from further evidence of the role played by Helicobacter pylori, to new information about the role of an apoptotic regulatory gene, bcl-10. Another area of productive research is the study of the mechanism of immune recognition and death signaling in follicular lymphomas. This should lead to refinements and improvements in an already very promising array of immunotherapeutic approaches, which currently ranges from vaccine development to allogeneic transplant strategies designed to induce a graft-versus-lymphoma effect. The clinical success of the chimeric anti-CD20 antibody, rituximab, leaves no doubt that biologic insights can lead to therapeutic advances. Researchers appear to be breaking free of the notion that alkylating agent therapy is the best option and the only viable treatment strategy for the indolent lymphomas. The current challenge is to apply new insights wisely.

Antibodies, Monoclonal↗
PubMed1999

Intensive dose ifosfamide and etoposide with G-CSF for stem cell mobilization in patients with non-Hodgkin's lymphoma.

We studied 36 patients with non-Hodgkin's lymphoma to evaluate the stem cell yield following recovery from intensive dose ifosfamide and etoposide given as mobilization chemotherapy. We also assessed the toxicity of the regimen and engraftment kinetics. All patients had intermediate grade lymphoma and had either failed to achieve a complete remission to induction chemotherapy or had relapsed. Patients received ifosfamide 10 g/m2 IV total dose given over 72 hours, etoposide 150 mg/m2 IV every 12 hours for 6 doses and G-CSF 10 microg/kg/d. Thirty-four patients went on to receive high-dose chemotherapy with BEAM or with CVP and BEAM. A median of 2 (1-10) apheresis was required to reach the target CD34+ count of >4 x 10(6)/kg. A median of 13.1 CD34+ cells/kg (4.1-148) was obtained. Toxicity was limited to mucositis in 3 patients, transient confusion and transient rise in liver function tests in 3 and 2 patients respectively. The median time to engraftment was 10 days (8-17) for all the patients undergoing high-dose chemotherapy. The regimen of intensive dose ifosfamide and etoposide along with G-CSF is well tolerated and in this group of patients has lead to successful stem cell harvests and sustained engraftment.

Adult↗
PubMed1999

Rituximab in indolent lymphoma: the single-agent pivotal trial.

Rituximab (Rituxan; IDEC Pharmaceuticals, San Diego, CA, and Genentech, Inc, San Francisco, CA) is a chimeric anti-CD20 monoclonal antibody that targets mature B cells and most B-cell malignancies. Rituximab was the first monoclonal antibody to be approved for therapeutic use for any malignancy. Its approval was based on a single-agent pivotal trial in patients with indolent B-cell lymphoma, in which 166 patients were enrolled from 31 centers in the United States and Canada. The overall results of the trial have been previously reported; additional aspects of the trial (eg, pharmacokinetics) have been reported separately as well. The current report includes an update, expansion, and synthesis of data from the single-agent pivotal trial of rituximab.

Antibodies, Monoclonal↗
PubMed1998

The clinical significance of molecular response in indolent follicular lymphomas.

Most patients with follicular lymphoma (FL) achieve a complete response (CR) after treatment, but eventually most of them, particularly those with stage IV, relapse due to minimal residual disease (MRD). The t(14;18) gives rise to a rearrangement of the bcl-2 oncogene that constitutes an excellent target for detection of MRD by polymerase chain reaction (PCR). One hundred ninety-four previously untreated patients with indolent FL and detectable bcl-2 rearrangement were studied. The PCR assay was used to detect bcl-2-rearranged cells in blood and marrow before and after treatment. Molecular response rate was 37%, 53%, 56%, and 66% at 3 to 5, 6 to 8, 9 to 14, and 15 to 18 months from the start of therapy, respectively. Although molecular response was higher among clinical CRs, one third of partial responders at 3 to 5 months also achieved a molecular response. Patients who achieved a molecular response during the first year of treatment had a significantly longer failure-free survival (FFS) than those who did not (4-year FFS: 76% v 38%, respectively; P < .001). Similar results were also observed in the subset of patients in clinical CR 1 year after treatment. By multivariate analysis, beta2-microglobulin (beta2-M; P < .01), and molecular response (P < .001) were the most important variables associated with outcome. When we combined beta2-M and molecular response, three prognostic groups emerged: (1) low beta2-M and molecular responders, (2) low beta2-M and nonresponders or high beta2-M and responders, and (3) high beta2-M and nonresponders. The 4-year FFS of these 3 groups were 86%, 65%, and 23%, respectively. Finally, patients who achieved molecular response and sustained it had better FFS than those who either reverted back to PCR-positive or who never achieved molecular response. Serial PCR analysis to determine the molecular response in FL correlates well with outcome especially when combined with pretreatment beta2-M.

Adolescent↗
PubMed1998

Risk factors, treatment, and outcome of central nervous system recurrence in adults with intermediate-grade and immunoblastic lymphoma.

To evaluate the incidence, risk factors, and outcome of central nervous system (CNS) recurrence in adult patients with non-Hodgkin's lymphoma, we evaluated 605 newly diagnosed patients with large-cell and immunoblastic lymphoma who participated in prospective chemotherapy studies. The Kaplan-Meier estimate of probability of CNS recurrence at 1 year after diagnosis was 4.5% (95% confidence interval [CI], 4.4 to 4.6). Twenty-four patients developed CNS recurrence after a median of 6 months from diagnosis (range, 0 to 44 months). In univariate analysis, an increased risk for CNS recurrence was associated with an advanced disease stage (P = .0014), an increased LDH (P = .0000), the presence of B-symptoms (P = . 0037), involvement of more than one extranodal site (P = .0000), poor performance status (P = .0005), and B-cell phenotype (P = .008). Bone marrow involvement (P = .005), involvement of parenchymal organs (P = .03), and involvement of skin, subcutaneous tissue, and muscle (P = .002) were also associated with an increased risk for CNS disease. Multivariate logistic regression analysis identified only involvement of more than one extranodal site (P = .0005) and an increased LDH (P = .0008) as independent predictors of CNS recurrence. Established CNS recurrence had a poor prognosis. Only 1 of 24 patients remains alive and the Kaplan-Meier estimate of probability of survival at 1 year after the diagnosis of CNS recurrence is only 25.3% (95% CI, 6.9 to 43.7). Intrathecal treatment provided symptomatic benefit in only 1 of 6 patients. Radiation treatment provided symptomatic improvement in 6 of 9 patients treated. However, remissions were short and followed by systemic or CNS recurrence. Serum LDH and involvement of more than one extranodal site are independent risk factors for CNS recurrence in patients with large-cell lymphoma. The presence of both risk factors identifies a patient group at high risk for CNS recurrence. Established CNS recurrence can be rapidly fatal. Transient responses occur after radiation treatment.

Adult↗
PubMed1998

Hodgkin's disease: correlation of clinical characteristics with probabilities for negative lymphangiogram vs. negative laparotomy findings in patients with Stage I supradiaphragmatic presentations vs. those in patients with Stage II.

PURPOSE: At a time both when late complications and second malignancies have become a growing concern and when staging laparotomy has been largely abandoned and comparative studies for staging Hodgkin's disease by state of the art computed tomography (CT) vs. lymphangiography have revealed minimal differences in results for these procedures, our purpose for undertaking this study was twofold. Our initial reason was to determine and compare probabilities for negative abdominal findings for patients with Stage I presentations with those for patients with Stage II as determined by lymphangiography and subsequently by laparotomy for those patients who had negative lymphangiograms. Our second reason, being an extension of the first, was to create a resource that can be used in conjunction with other information for arriving at appropriate treatment decisions including giving either more or particularly less than standard institutional therapy and especially with respect to the abdomen. METHODS AND MATERIALS: Data on 714 patients with prelymphangiogram Stage I-II upper torso presentations of Hodgkin's disease were entered prospectively in our database between 1968 and 1987. Twenty-eight with lymphocyte predominant disease, who had both negative lymphangiogram and negative laparotomy findings and 17 with questionable diagnoses of lymphocyte-depleted or unclassified disease were excluded from subsequent analyses of 669 patients with nodular sclerosis (NS) and mixed cellularity (MC) diagnoses. RESULTS: Stage I: in final logistic models, negative lymphangiogram findings were associated strongly with a combination of no constitutional symptoms and nodular sclerosis histology, whereas negative laparotomy findings correlated strongly with a combination of no constitutional symptoms and female sex. Predicted probabilities depended on the ratios of favorable to unfavorable characteristics. Stage II: in final logistic models, negative lymphangiogram findings were associated strongly with a combination of no constitutional symptoms, nodular sclerosis histology, age <40 years, and <4 involved sites, whereas negative laparotomy findings correlated strongly with a combination of <4 involved sites and mediastinal disease. Predicted probabilities again depended on the ratios of favorable to unfavorable characteristics. CONCLUSION: This study demonstrated that probabilities for negative abdominal findings for patients with supradiaphragmatic presentations of NS and MC Hodgkin's disease depended on: 1) whether the disease presented as Stage I or as Stage II; 2) whether staging was limited to a lymphangiogram or whether it included a laparotomy; and 3) or whether the clinical features associated with the presenting stage and methods of staging were favorable or unfavorable.

Abdomen↗
PubMed1998

Alternating triple therapy for the treatment of intermediate grade and immunoblastic lymphoma.

BACKGROUND: CHOP is currently considered the gold standard of treatment for intermediate grade lymphomas. We designed a new regimen known as 'ATT' (alternating triple therapy) which uses three non-cross resistant combinations in alternating sequence for nine cycles. MATERIALS AND METHODS: This is a phase II clinical trial with comparison to CHOP/CMED historical controls using prognostic factors. The tumor score system was used to evaluate the results of this trial. Two hundred sixty-eight eligible patients who had one or more of the following adverse features: bulky disease, elevated LDH or > 1 extranodal site were analyzed. Outcome measures consist of survival and failure free survival. RESULTS: At a median follow-up of 32 months, there was no statistically significant difference in survival for those with favorable prognostic factors (tumor score < or = 2). However, there was a statistically significant difference in favor of ATT for those with unfavorable tumor scores. When we examined the failure-free survival of those with unfavorable tumor scores, we again observed a superiority for the ATT regimen over CHOP/CMED but the opposite was true for those with favorable tumor scores. We also found a statistically significant difference in favor of the ATT regimen when compared with CHOP/CMED for patients < or = 60 years old with a tumor score > or = 3, while no advantage was found for those > 60 years. CONCLUSIONS: ATT appears more effective but only for patients < 60 years old with unfavorable tumor scores. In those older than 60 years with favorable tumor score, CHOP/CMED appears superior. ATT might be an adequate regimen for young patients with poor prognostic features while CHOP/CMED might be a better choice for those with good prognosis irrespective of age. For those > 60 years with unfavorable tumor scores neither ATT or CHOP/CMED were adequate treatment. Because of the phase II nature of this study, these conclusions should be considered as hypotheses which require prospective testing.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1998

Association of serum Rituximab (IDEC-C2B8) concentration and anti-tumor response in the treatment of recurrent low-grade or follicular non-Hodgkin's lymphoma.

BACKGROUND: Monoclonal antibodies are being utilized for treatment of patients with low-grade non-Hodgkin's lymphoma as well as other cancers. Results from phase I and II clinical studies has shown that the chimeric monoclonal antibody Rituximab has minimal toxicity and significant therapeutic activity in low grade non-Hodgkin's lymphoma. PATIENTS AND METHODS: We have recently reported on a multicentre pivotal phase III clinical trial involving 166 patients with recurrent low-grade lymphoma who were treated with four infusions of Rituximab. Eighty patients (48%) achieved objective responses including 10 patients (6%) with complete responses. Overall, 126 patients (76%) had a > or = 20% reduction in overall tumor size. The median response duration and time to progression are 11.6 and 13.2 months, respectively. The infusional and long term toxicities were limited. RESULTS: In this report we describe the pharmacokinetic data obtained on these patients. Measurable concentrations of Rituximab were detected in all patients after the first infusion and increased throughout the treatment course. The half-life of the monoclonal antibody increased from 76.3 hours after the first infusion to 205.8 hours after the fourth infusion and was concomitant with a four-fold decrease in the antibody clearance. At three months and six months post-treatment, the median Rituximab serum levels were 20.3 micrograms/ml (range 0.0 to 96.8 micrograms/ml in 104 patients) and 1.3 micrograms/ml (range 0.0-28.7 micrograms/ml in 13 patients), respectively. A statistically significant correlation was found between the median antibody concentration and response for multiple time points during the treatment and followup. The mean serum antibody concentration was also inversely correlated with measurements of tumor bulk and with the number of circulating B cells at baseline. CONCLUSIONS: We conclude that Rituximab is therapeutically effective against B-cell lymphoma. Pharmacokinetic data suggests that certain subsets of patients may possibly benefit from increased dosing and studies to address this are currently underway.

Antibodies, Monoclonal↗