Pablo Parker
City of Hope National Medical Center
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Pablo Parker.
The New England Journal of Medicine | 1993
Nelson J. Chao; Gerhard M. Schmidt; Joyce C. Niland; Michael D. Amylon; Andrew Dagis; Gwynn D. Long; Auayporn Nademanee; Robert S. Negrin; Margaret R. O'Donnell; Pablo Parker; Eileen Smith; David S. Snyder; Anthony S. Stein; Ruby M. Wong; Karl G. Blume; Stephen J. Forman
BACKGROUND Acute graft-versus-host disease (GVHD) following allogeneic bone marrow transplantation remains a serious problem. In a clinical trial, we tested the combination of cyclosporine and prednisone with and without methotrexate for the prevention of GVHD. METHODS One hundred fifty patients with either acute leukemia in first complete remission, chronic myelogenous leukemia in first chronic phase, or lymphoblastic lymphoma in first complete remission were enrolled in the study. All the patients were given fractionated total-body irradiation (1320 cGy) and etoposide (60 mg per kilogram of body weight) in preparation for transplantation, and received bone marrow from genotypically histocompatible donors. To prevent GVHD, they were randomly assigned to prophylactic treatment with either cyclosporine, methotrexate, and prednisone or cyclosporine and prednisone without methotrexate. All the patients received standardized supportive care after transplantation, including intravenous gamma globulin. RESULTS Patients receiving cyclosporine, methotrexate, and prednisone had a significantly lower incidence of acute GVHD of grades II to IV (9 percent) than those receiving cyclosporine and prednisone (23 percent, P = 0.02). Multivariate regression analysis demonstrated that an increased risk of acute GVHD was associated with an elevated serum creatinine concentration (P = 0.006) and treatment with cyclosporine and prednisone alone (P = 0.02). The lower incidence of acute GVHD was not associated with a higher rate of relapse of leukemia or lymphoma. There was no significant difference in disease-free survival at three years between the two treatment groups (64 percent with the three-drug regimen vs. 59 percent with the two-drug regimen, P = 0.57). CONCLUSIONS The combination of cyclosporine, methotrexate, and prednisone was more effective in preventing acute GVHD of grades II to IV than was the combination of cyclosporine and prednisone without methotrexate.
Bone Marrow Transplantation | 2000
Robert H. Collins; Sc Goldstein; Sergio Giralt; John E. Levine; David L. Porter; William R. Drobyski; John Barrett; M. Johnson; A. Kirk; Mary M. Horowitz; Pablo Parker
Donor leukocyte infusion (DLI) has well-documented activity in CML but the role of DLI in other diseases is less well defined. To evaluate the strategy in acute lymphocytic leukemia (ALL) we evaluated 44 ALL patients from 27 centers who were treated with DLI. Patients with persistent or recurrent disease received DLI from the original marrow donor (30 matched related, four mismatched family, and 10 matched unrelated). Chemotherapy was given before DLI to 28 patients. Of 15 patients who received no pre-DLI chemotherapy, two achieved complete remissions, lasting 1112 and 764+ days. In four patients who received DLI as consolidation of remission induced by chemotherapy or immunosuppression-withdrawal, duration of remission post DLI was 65, 99, 195 and 672+ days. Of 25 patients who received DLI in the nadir after chemotherapy, 13 survived ⩾30 days post DLI but did not achieve remission, seven died within less than 30 days post DLI, and five entered remissions that lasted 42, 68, 83, 90, 193 days. Seven patients who did not respond to the initial DLI received a second DLI; none of these patients attained durable remission. Eighteen of 37 evaluable patients developed acute GVHD and five of 20 evaluable patients developed chronic GVHD. Overall actuarial survival is 13% at 3 years. In conclusion, DLI has limited benefit in ALL. New approaches are needed in this group of patients. Bone Marrow Transplantation (2000) 26, 511–516.
Bone Marrow Transplantation | 2000
M Salama; Thomas J. Nevill; Deborah Marcellus; Pablo Parker; M. Johnson; A. Kirk; David L. Porter; Sergio Giralt; John E. Levine; William R. Drobyski; A. J. Barrett; Mary M. Horowitz; Robert H. Collins
Donor leukocyte infusion (dli) has well-documented activity in cml, but the role of dli in other diseases is less well defined. to evaluate the strategy in multiple myeloma (mm) we evaluated 25 mm patients from 15 centers who were treated with dli. patients with persistent or recurrent disease after allogeneic bmt received dli from the original marrow donor (23 matched related, one mismatched family, and one matched unrelated). chemotherapy was given before dli in three patients. two of 22 patients responded completely to dli alone and three patients responded to the combination of dli and chemotherapy. nine patients who had not had sufficient disease control after dli were given additional dlis; five of these patients had either complete (two) or partial (three) responses. thirteen of 25 evaluable patients developed acute gvhd and 11 of 21 evaluable patients developed chronic gvhd; all responders developed gvhd. no patients developed post-dli pancytopenia. four patients had responses which lasted >1 year after DLI, three patients had responses which lasted <1 year, and three patients had ongoing responses but with follow-up <1 year. In conclusion, DLI has anti-myeloma activity but the strategy is limited by no response or short duration of response in a significant percentage of patients and by significant GVHD in the majority of the responders. Bone Marrow Transplantation (2000) 26, 1179–1184.
Journal of Clinical Oncology | 1994
Auayporn Nademanee; I Sniecinski; G M Schmidt; Andrew Dagis; Margaret R. O'Donnell; David S. Snyder; Pablo Parker; Anthony S. Stein; E P Smith; Arturo Molina
PURPOSE To evaluate (1) the effect of granulocyte colony-stimulating factor (G-CSF) on peripheral-blood stem-cell (PBSC) mobilization; (2) the rate of hematopoietic recovery after G-CSF-mobilized PBSC transplantation; and (3) the outcome of high-dose myeloablative therapy and PBSC transplantation in patients with relapsed or refractory lymphoma. PATIENTS AND METHODS Ninety-five patients with lymphoma underwent high-dose therapy followed by PBSC transplant in three sequentially treated cohorts of patients in a nonrandomized study. The first 30 patients received nonmobilized PBSCs (unprimed) without G-CSF after transplant, the next 26 patients received PBSC that were mobilized with G-CSF 5 micrograms/kg/d (primed-5) plus G-CSF after transplant, and the last 39 patients received PBSC mobilized by G-CSF 10 micrograms/kg/d (primed-10) plus G-CSF after transplant. The conditioning regimen consisted of fractionated total-body irradiation (FTBI) 12 Gy in combination with etoposide 60 mg/kg and cyclophosphamide 100 mg/kg. Patients with prior radiotherapy received carmustine (BCNU) 450 mg/m2 instead of FTBI. RESULTS The use of G-CSF-mobilized PBSCs in combination with G-CSF posttransplant resulted in a significantly accelerated time to recovery of both granulocyte and platelet when compared with the unprimed group. The median number of days to an absolute granulocyte count (ANC) of greater than 0.5 x 10(9)/L was 10 days for G-CSF primed versus 20 days for the unprimed (P = .0001). The median days to platelet transfusion independence was 16 and 31 days (P = .0001) for the G-CSF primed and unprimed, respectively. There were also significant reductions in the number of platelet (P = .02) and RBC transfusions (P = .006) for the G-CSF primed. Multivariate analysis of prognostic factors identified CD34+ cell dose as the only additional factor predicting engraftment. Sixty-nine patients are alive at a median follow-up of 15.9 months (range, 7.4 to 63.7). The cumulative probability of 2-year disease-free survival is 59% (95% confidence interval [CI], 36% to 79%) and 39% (95% CI 25% to 55%) for patients with Hodgkins disease and non-Hodgkins lymphoma, respectively. CONCLUSION The use of G-CSF-mobilized PBSC after high-dose myeloablative therapy resulted in a rapid, complete, and sustained hematopoietic recovery. Disease-free survival over 2 years can be achieved in some patients with relapsed lymphoma after high-dose therapy and PBSC transplantation. However, longer follow-up is required to confirm the curability of this approach.
Leukemia | 1999
David S. Snyder; Auayporn Nademanee; O’Donnell; Pablo Parker; Anthony S. Stein; Kim Margolin; George Somlo; Arturo Molina; Ricardo Spielberger; Ashwin Kashyap; Henry Fung; Marilyn L. Slovak; Andrew Dagis; Robert S. Negrin; Amylon; K. G. Blume; Stephen J. Forman
Between 1984 and 1997, 23 consecutive patients with Philadelphia chromosome-positive acute lymphoblastic leukemia in first complete remission were treated with allogeneic bone marrow transplants from HLA-matched siblings. All patients but one were conditioned with fractionated total body irradiation (1320 cGy) and high-dose etoposide (60 mg/kg). One patient received high-dose cyclophosphamide instead of etoposide, and another patient received both drugs. Nine patients died following BMT, two from relapsed leukemia, and seven from transplant-related causes. The 3-year probabilities of disease-free survival and relapse are 65% and 12%, respectively. For patients transplanted after 1992, these probabilities are 81% (48–95%, 95% confidence interval) and 11% (2–50%), respectively. The relatively low relapse rate in this group of patients compared to published reports may reflect the enhanced anti-leukemic activity of etoposide in combination with FTBI compared to other conditioning regimens. The enhancement in overall survival for patients transplanted after 1992 may reflect improvements in supportive care, in particular, the prophylaxis of serious fungal and viral infections.
Bone Marrow Transplantation | 2001
Khoury H; Kashyap A; Douglas Adkins; Randy A. Brown; Gregory E. Miller; Ravi Vij; Peter Westervelt; K. Trinkaus; Lawrence T. Goodnough; Robert J. Hayashi; Pablo Parker; S Forman; John F. DiPersio
Acute graft-versus-host disease (aGVHD) is a major cause of mortality after allogeneic stem cell transplantation. Although initial treatment with corticosteroids is effective in the majority of patients, 30–60% develop steroid resistance. Anti-thymocyte globulin (ATG) is commonly used as first-line therapy for steroid resistant (SR) aGVHD. However, data on its efficacy are limited. At two institutions we reviewed the results of treatment with ATG of 58 patients with SR aGVHD. Initial manifestations of aGVHD were treated with 2 mg/kg/day of methylprednisolone (MP). Equine ATG was administered as first-line therapy for SR aGVHD, a median of 9 days (range, 3 to 39) after initiation of MP. At the time of initiation of ATG, IBMTR severity indices B, C and D were observed in 6%, 40% and 54% of patients, respectively. Improvement was observed in 30% of patients treated with ATG. Skin disease was more likely to improve with ATG (79%), while progression of gut and liver aGVHD was observed in 40% and 66% of patients, respectively. Despite initial improvement, 52 patients (90%) died a median of 40 days after ATG therapy from progressive aGVHD and/or infection (74%), ARDS (15%), or relapse (11%). Only six patients (10%), three of whom had aGVHD limited to the skin at the time ATG was administered, are long-term survivors. We conclude that initial improvement of SR aGVHD occurs with ATG in a minority of patients, and very few patients become long-term survivors. Furthermore, this treatment is associated with a high rate of major complications. Bone Marrow Transplantation (2001) 27, 1059–1064.
Journal of Clinical Oncology | 1987
Margaret R. O'Donnell; Auayporn Nademanee; David S. Snyder; G M Schmidt; Pablo Parker; P J Bierman; J L Fahey; Anthony S. Stein; R A Krance; A D Stock
Twenty patients (age range, 4 to 48 years; median age, 36 years) with de novo or drug-induced myelodysplastic syndromes or myeloproliferative disorders were treated with myeloablative immunosuppressive therapy followed by bone marrow transplantation (BMT). Four preparative regimens were used; three regimens consisted of combined total body irradiation (TBI) and chemotherapy and one of combination chemotherapy only. One patient received marrow from his identical twin brother, whereas the other 19 patients were grafted with marrow from histocompatible siblings. In 19 patients the abnormal clone was at least temporarily ablated, while in one patient the congenital myelodysplasia persisted. Eight patients are alive and well for +108 to +3,359 days post-transplantation. Nine patients died of transplant-related complications (six of interstitial pneumonia, two of gastrointestinal bleeding, and one of fungal sepsis) and three patients died with persisting or recurring disease. One patient with a late recurrence has undergone a second successful bone marrow transplant procedure. Outcome of BMT was not related to French-American-British (FAB) type, marrow fibrosis, cytogenetic abnormalities, or preparation regimen. Marrow transplantation as a means of providing long-term disease-free survival and possible cure should be considered in patients if a suitable donor is available.
Biology of Blood and Marrow Transplantation | 1998
Eileen Smith; Irena Sniecinski; Andrew Dagis; Pablo Parker; David S. Snyder; Anthony S. Stein; Auayporn Nademanee; Margaret O’Donnell; Arturo Molina; Gerhard M. Schmidt; Daniel E. Stepan; Neena Kapoor; Joyce C. Niland; Stephen J. Forman
Extracorporeal photochemotherapy (EP) is a therapeutic approach to the treatment of drug-resistant graft-vs.-host disease (GVHD) that uses the known immunosuppressive and immunomodulatory effects of ultraviolet light. In 1990, we initiated a pilot study to evaluate the efficacy and safety of EP in patients with refractory GVHD. Between 1991 and 1996, six patients with acute grade IV liver GVHD, 12 patients with chronic following acute GVHD, and six patients with de novo chronic GVHD were treated with EP. All patients had failed to respond to conventional GVHD immunosuppressive drug therapy of cyclosporine and prednisone. The six patients with acute liver GVHD had also received antithymocyte globulin (ATG); therapy for chronic GVHD included thalidomide in eight patients, psoralen plus ultraviolet A in five patients, and ATG in two patients. All patients with acute liver GVHD had progressive liver failure with short survival despite frequent EP. The response rate with EP treatment was 3 of 6 for patients with de novo chronic GVHD and 3 of 12 for patients with chronic following acute GVHD. Three patients with bronchiolitis obliterans had either no response or no documented disease progression while undergoing EP. Side effects of EP were minor and included gastrointestinal upset frequently, catheter-related sepsis in four patients, increased red blood cell and platelet transfusion requirements in one patient, and leukopenia in two patients. EP was discontinued in three patients because of side effects, including GI upset in one patient and bone marrow suppression in two patients. Side effects were reversible with the discontinuation of EP. We were unable to correlate response to EP with the level of methoxypsoralen, number of lymphocytes treated, or pattern of pre- and posttreatment CD4/CD8 ratio. We concluded that EP has some efficacy in the treatment of drug-resistant chronic GVHD, with minor overall toxicity.
Blood | 2010
Ryotaro Nakamura; Roberto Rodriguez; Sepideh Shayani; Pablo Parker; Stephen J. Forman
Combination tacrolimus and sirolimus graft-versus-host disease (GVHD) prophylaxis for allogeneic transplant in patients conditioned with a fractionated total body irradiation-based regimen has shown encouraging results. We studied this prophylaxis combination in 85 patients receiving a matched-sibling transplant conditioned with 3 different regimens:fludarabine-melphalan (n = 46); total body irradiation-etoposide (n = 28), and busulfan-cyclophosphamide (n = 11). The conditioning regimens were completed on day -4. Sirolimus and tacrolimus were started on day -3 to avoid overlap with conditioning therapy. All patients engrafted, with a median time to neutrophil engraftment of 15 days. The cumulative incidence of acute GVHD grades II to IV and III to IV was 43% and 19%, respectively, with no significant difference by conditioning regimen. The 2-year cumulative incidence of chronic GVHD was 46%. With a median follow-up of 26 months, disease-free survival was 58% and overall survival, 66%. The day-100 and 2-year nonrelapse mortality was 4.8% and 10.2%, respectively. The overall incidence of thrombotic microangiopathy was 19%, and it was significantly higher with busulfan/cyclophosphamide (55%, P = .005). Tacrolimus plus sirolimus is an effective combination for acute GVHD prophylaxis and is associated with very low nonrelapse mortality. Thrombotic microangiopathy is a significant complication with this regimen, particularly in patients receiving busulfan/cyclophosphamide.
Medicine | 1996
Pablo Parker; Nelson J. Chao; Johnathan Ben-ezra; Neal E. Slatkin; Harry Openshaw; Joyce C. Niland; Charles Linker; Brian S. Greffe; Ashwin Kashyap; Arturo Molina; Auayporn Nademanee; Margaret R. O'Donnell; Ina Planas; Khalil Sheibani; Eileen Smith; David S. Snyder; Ricardo Spielberger; Anthony S. Stein; Daniel E. Stepan; Karl G. Blume; Stephen J. Forman
A syndrome indistinguishable from idiopathic polymyositis occurred in 11 patients as a manifestation of chronic GVHD. All patients had elevation of creatine phosphokinase (CPK). Immunohistology demonstrated the effector cells in the muscle infiltrates as cytotoxic T cells, a finding similar to idiopathic polymyositis. Polymyositis is a rarely reported complication of chronic graft-versus-host disease (GVHD) with only 8 cases described in the literature. We encountered this syndrome in a small but significant percentage of our patients with chronic GVHD. Polymyositis associated with chronic GVHD does not affect the overall prognosis for the patient. Moreover, polymyositis can be the only manifestation of chronic GVHD. Awareness of this complication is important because it can be confused with other causes of muscle weakness after bone marrow transplantation. Finally, prompt initiation of corticosteroid therapy results in a rapid improvement of the associated symptoms.