Randomized trial of recombinant platelet factor 4 versus protamine for the reversal of heparin anticoagulation in humans.

BACKGROUND: Protamine reverses heparin anticoagulation, but it can have important side effects. We compared the safety and effectiveness of intravenous recombinant platelet factor 4 (rPF4) as an alternative to protamine in a randomized blinded trial. METHODS AND RESULTS: In 81 patients having diagnostic cardiac catheterization, baseline hemodynamics were measured after a 5000-U bolus of heparin. Repeat measurements were obtained at the end of the procedure, and the anticoagulation status was determined by an activated coagulation time (ACT) and activated partial thromboplastin time (aPTT). Patients then received either protamine (50 mg IV over 10 minutes) or rPF4 (1.0 mg/kg IV over 2 minutes) in a blinded fashion. Serial measurements of hemodynamic and clotting functions were performed 5, 10, 20, and 30 minutes after drug administration. Follow-up measurements and clinical assessments were made at 1, 4, 6, and 24 hours later and after 7 days. Before drug administration, ACTs, aPTTs, and hemodynamics were similar among the groups. After drug infusion, there was no difference in ACT between the protamine and rPF4 patients. At 20 and 30 minutes after drug infusion, ACT and aPTT were slightly higher in those receiving rPF4, but these changes were small and of no clinical significance. There were no clinically meaningful differences in any of the hemodynamic variables between the groups, and there were no serious side effects in any patient. CONCLUSIONS: At the dose used in this study, rPF4 was well tolerated and reversed the anticoagulant effect of heparin. These data support its continued evaluation as an alternative to protamine after cardiac surgery.

Phase I trial of recombinant platelet factor 4 (rPF4) in patients with advanced colorectal carcinoma.

BACKGROUND: Recombinant platelet factor 4 (rPF4) is a naturally occurring protein found in platelet alpha granules that can inhibit angiogenesis. METHODS: In this Phase I trial, 9 patients with metastatic colorectal cancer who had failed 5-FU treatment received rPF4 at doses ranging from 0.3 to 3.0 mg/kg via 30-minute infusion. Three additional patients were treated with the 3 mg/kg dose over a 6-hour period of infusion. RESULTS: The only toxicity encountered was mild leg twitching in 2/3 patients treated with the 6-hour infusion. One patient with a history of phlebitis developed a lower extremity deep venous thrombosis after the first dose of rPF4. A mild rise in fibrinogen level was noted in several patients. Of the 11 evaluable patients, there were no clinical responses to treatment. CONCLUSIONS: rPF4 is well tolerated at the doses and schedules tested. No clinical responses were observed. Prolonged infusion schedules should be investigated.

Reversal of heparin anticoagulation by recombinant platelet factor 4 in humans.

BACKGROUND: Protamine is used to reverse the anticoagulant effects of heparin, but it can have important side effects. Platelet factor 4 (PF4) is a protein found in platelet alpha granules that binds to and thereby neutralizes heparin. We evaluated the safety and effectiveness of intravenous recombinant PF4 to neutralize heparin anticoagulation after cardiac catheterization in a phase 1, open-label trial. METHODS AND RESULTS: The study group consisted of 18 patients having diagnostic cardiac catheterization. Heparin (5000 U) was given after vascular access was obtained. In the first 12 patients, additional heparin was given at the conclusion of the procedure so that all patients had activated coagulation times > 300 seconds before rPF4 was given. Three patients each received 0.5, 1.0, 2.5, or 5.0 mg/kg rPF4 over a period of 3 minutes at the conclusion of the catheterization procedure. In 6 additional patients, extra heparin was not given at the conclusion of the procedure, and 1.0 mg/kg rPF4 was given. Hemodynamic measurements, cardiac output, and serial blood tests were performed 5, 10, 20, and 30 minutes after rPF4 and then into the next 24 hours. There were no serious side effects in any patient, despite transient rPF4 levels as high as 14,870 ng/mL in the patients receiving 5.0 mg/kg. One patient receiving 2.5 mg/kg had a slight transient rise in liver enzymes possibly related to the rPF4. There were no important hemodynamic effects of rPF4 administration at any dose used. Doses of 2.5 and 5.0 mg/kg were uniformly effective in reversing the anticoagulant effect of heparin. At lower doses, rPF4 neutralized the effects of heparin in most but not all patients. Pharmacokinetic analysis suggested a monophasic and one-compartment clearance of the PF4-heparin complex. No neutralizing factors to rPF4 were detected in the samples collected 7 days after dosing. CONCLUSIONS: rPF4, in doses ranging from 0.5 to 5.0 mg/kg over 3 minutes, had no serious side effects. Given in sufficient amounts, rPF4 can completely and rapidly reverse the anticoagulant effects of heparin.

Phase I trial of m-BACOD and granulocyte macrophage colony stimulating factor in HIV-associated non-Hodgkin's lymphoma.

The use of full-dose intensive regimens of chemotherapy in patients with HIV-associated lymphoma has often resulted in severe toxicity, treatment delay, and reduced subsequent dosing. We conducted a Phase I trial to evaluate the toxicity of the combination of m-BACOD (methotrexate, Bleomycin, doxorubicin, cyclophosphamide, vincristine, dexamethasone) with granulocyte-macrophage colony stimulating factor (GMCSF) in these patients. A total of 17 patients were entered and treated at three dose levels of m-BACOD in combination with a fixed dose of GMCSF. Eight patients received standard dose m-BACOD plus GMCSF without experiencing dose-limiting hematologic toxicity, although significant nonhematologic toxicity was seen. We conclude that it is feasible to treat patients with HIV-associated lymphoma using standard dose m-BACOD plus GMCSF, but further study is needed to determine whether full-dose regimens improve survival when compared with reduced dose regimens in these individuals.

Pharmacokinetics and pharmacodynamics of granulocyte-macrophage colony-stimulating factor and zidovudine in patients with AIDS and severe AIDS-related complex.

Granulocytopenia is a complication of human immunodeficiency virus disease, as well as a toxic manifestation of zidovudine therapy. To evaluate pharmacokinetic and pharmacodynamic relationships, 11 AIDS-AIDS-related complex patients who had developed zidovudine-associated granulocytopenia (mean absolute neutrophil count, 1,077/mm3) were examined after addition of granulocyte-macrophage colony-stimulating factor (GM-CSF) to zidovudine. GM-CSF was administered as a daily (1.0 or 0.3 micrograms/kg) or every-other-day (0.3 micrograms/kg) subcutaneous dose over a 28-day period. Zidovudine was continued at the same daily dosage as was previously being administered. Of 11 patients, 7 (1.0 micrograms/kg, n = 5; 0.3 micrograms/kg, n = 2) had a pharmacologic response to GM-CSF with an increase to a mean absolute neutrophil count of 3,189 cells per mm3 at 4 weeks (P < 0.05). The peak concentration of GM-CSF in plasma ranged from 11.5 to 84.4 pg/ml, and the time to peak ranged from 1 to 3 h. No correlation between GM-CSF disposition and hematologic response was noted. A decreased plasma zidovudine-glucuronide/zidovudine ratio was noted after 1 week of GM-CSF, and an increase in the area under the plasma concentration-versus-time curve for zidovudine was found in three patients after 4 weeks. Low doses of GM-CSF can raise the granulocyte count in patients with zidovudine-induced neutropenia. The use of GM-CSF and zidovudine may represent a viable treatment option for persons with human immunodeficiency virus infection who develop neutropenia while receiving zidovudine but do not tolerate alternative nucleoside analogs. Further studies are needed to assess the complex interaction between these two agents.

Recombinant human interleukin 4 (IL-4) given as daily subcutaneous injections--a phase I dose toxicity trial.

Recombinant Interleukin 4 was administered by subcutaneous injection at daily doses of 0.5, 1.0 or 5.0 micrograms kg-1 to nine patients as part of a Phase I Dose Toxicity Study. Dose limiting toxicity was reached at 5 micrograms kg-1 day-1. Symptoms of toxicity included fatigue, 'flu like symptoms and elevated liver enzymes. Modest but significant elevations of neutrophil and platelet counts occurred. No clear evidence of antitumour effects emerged although pain in metastatic lymph nodes and a small fall in myeloma paraprotein levels during dosing were observed. In vitro and murine in vivo studies indicate that patients with lymphoproliferative disease should be selected for Phase II trials.

Granulocyte-macrophage colony-stimulating factor (GM-CSF) as an adjunct to autologous hemopoietic stem cell transplantation for lymphoma.

OBJECTIVE: To determine the hemopoietic effects of recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF) in patients having autologous hemopoietic stem cell transplantation for Hodgkin or non-Hodgkin lymphoma. DESIGN: Placebo or GM-CSF was administered after bone marrow or peripheral blood stem cell transplantation or both in a randomized, double-blind phase III trial by daily intravenous infusion (10 micrograms/kg body weight) until absolute neutrophil counts reached greater than or equal to 1000/mm3 on 3 consecutive days. SETTING: Bone marrow transplantation unit in a university hospital. PATIENTS: Sixty-nine consecutive patients with Hodgkin or non-Hodgkin lymphoma received GM-CSF (36 patients) or placebo (33 patients). MEASUREMENTS AND MAIN RESULTS: Patients who received GM-CSF achieved absolute neutrophil counts greater than or equal to 500/mm3 (median, 12 compared with 16 days, P = 0.02) and absolute neutrophil counts greater than or equal to 1000/mm3 (median, 15 compared with 24 days, P less than 0.001) more quickly than patients who received placebo. Multivariate analysis indicated that use of GM-CSF, peripheral blood stem cells, and unpurged bone marrow were the strongest predictors for early neutrophil recovery greater than 500/mm3. Bacterial infections were significantly reduced in the GM-CSF group (P = 0.04). Delayed engraftment (neutrophils less than 500/mm3 at day 30) occurred in 26% and 17% of the placebo and GM-CSF groups, respectively, and correlated with the absence of detectable myeloid progenitor cells (colony-forming units-granulocyte macrophage, CFU-GM) (P less than 0.001) in marrow aspirate specimens obtained on day 15. Time to platelet independence, duration of hospital stay, severe adverse reactions, relapse, and disease-free survival rates did not differ significantly between the two groups. CONCLUSIONS: Administration of GM-CSF after autologous hemopoietic stem cell transplantation in patients with lymphoma resulted in accelerated myeloid recovery, particularly in patients who received peripheral blood stem cells and nonpurged bone marrow, and was associated with a decreased incidence of bacterial infections.

alpha Interferon: the potential drug of adjuvant therapy: past achievements and future challenges.

This paper aims to summarize current experience with alpha interferon and provide direction for future study. There are four areas in which alpha interferon has proven or potential activity: antiviral, premalignant, adjuvant and advanced disease settings. The three main viral diseases in which interferon alfa-2b has been shown to have activity are chronic viral hepatitis, acquired immunodeficiency syndrome, and human papilloma virus infections. In vitro studies suggest that alpha interferon may inhibit transformation of some premalignant conditions into malignant disease; e.g., vaginal intraepithelial neoplasia. In the adjuvant setting, it is possible that a biological response modifier, such as alpha interferon, may have a role in helping the immune system to destroy residual tumour cells following tumour bulk reduction with radiation or chemotherapy. A higher response rate has been seen in patients with small tumour bulk compared to those with large tumour bulk (e.g., malignant melanoma, ovarian carcinoma), and in patients with early, rather than late, disease (e.g., chronic myelogenous leukaemia, hairy cell leukaemia, multiple myeloma, non-Hodgkin's lymphoma). This may be due to efficacy in a small tumour bulk setting or due to an immunoadjuvant role. In advanced disease, the question is how best to exploit the possible synergistic effects between alpha interferon and other therapeutic modalities. The optimum dose, schedule and patient populations for combined treatment have yet to be determined. The major objective of this paper is to determine how best to capitalize upon the current state of knowledge to build for future trials of alpha interferon, and to determine whether the existing data suggest an adjuvant role for interferon after initial tumour regression.

Survival Experience of 195 Patients with Hairy Cell Leukemia Treated in a Multi-Institutional Study with Interferon-Alfa 2B.

One hundred ninety-five patients were entered into a multi-institutional study of interferon alfa 2b from 1983-1986; follow-up was completed through June 1989. A complete remission was documented in 7 patients, a partial remission in 152 patients, a minor response in 10 patients, and no response in 26 patients. One-hundred fifty-nine of the 195 patients treated (81%) had a normalization of their peripheral blood counts by the criteria used. To date, 17 patients have died. Only 3 of the 159 patients (2%) with a PR or CR have expired. Three of 10 MR patients have expired and 11 of 26 NR patients have expired. Of the 11 who expired, 7 did so before receiving an adequate duration of treatment. Three of the NR patients died within 1 week of starting interferon from intracranial hemorrhages secondary to severe thrombocytopenia (present prior to initiation of interferon) and 4 NR patients died of infectious deaths within 2 months of initiating interferon therapy secondary to severe neutropenia (present prior to initiation of interferon). Of the 17 NR's who remained alive and on-study for at least 6 months, only 2 eventually died, both after failing subsequent pentostatin therapy. Systemic therapy with agents that induce a more rapid response such as pentostatin or 2-chlorodeoxy-adenosine, or the combination of interferon plus growth factor are indicated in these severely cytopenic patients.

Low Dose Interferon Alfa-2B for the Induction of Remission of Hairy Cell Leukemia: A Multi-institutional Study of 49 Patients.

This multicenter study reports on 49 patients with hairy cell leukemia (HCL) who were treated subcutaneously with alfa-2b interferon (Intron A, Schering Corporation, Kenilworth, N.J.), three times a week at a reduced dosage of 200,000 units/m(2), one-tenth the dose of the standard 2 million units/m(2). The response rate (normalized blood counts) was 22% (11 of 49); an additional 12 patients had a minor response for an overall response rate of 47% (23 of 49). When response was assessed by prior IFN therapy, no significant difference was noted. Five of 21 (24%) with no prior IFN and 6 of 28 (21%) with prior IFN therapy achieved at least a normalization of blood counts (p = 0.07). The response rate with low-dose interferon is inferior to that with standard dose interferon and should not be used for remission induction, but should be evaluated for its role in long-term maintenance of response.

High-dose melphalan and granulocyte-macrophage colony-stimulating factor for refractory multiple myeloma.

High-dose melphalan has induced remissions in about 40% of patients with refractory myeloma, but the mortality has been high, at about 20%, due to complications of prolonged granulocytopenia. In an attempt to stimulate earlier granulocyte recovery, recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF) was administered subcutaneously to 23 patients with refractory myeloma who had been treated with melphalan at a high dose of 100 mg/m2. Thirty-nine percent of patients achieved marked tumor cytoreduction by at least 75%, 2 died within 2 months from infectious complications during severe neutropenia; and median durations of relapse-free and overall survival were 7 and 10+ months, respectively. The nine patients presenting with both advanced age over 50 years and a long history of prior therapy of over 1 year required significantly longer median times of 31 days for granulocytes and of 63 days for platelets to reach safe levels of at least 500/microL and 50,000/microL, respectively, than the 14 remaining patients who had none or only one of these adverse features (21 and 26 days, respectively). In a historic control of 43 patients treated previously with high-dose melphalan but without GM-CSF, hematologic recovery to the aforementioned levels of granulocytes and platelets proceeded over almost 5 weeks, regardless of age and prior treatment exposure. Thus GM-CSF seems to hasten marrow recovery, especially in patients with adequate normal marrow stem-cell reserve as defined by younger age or less prior therapy. While not shortening the duration of neutropenia, GM-CSF dose increments (from 0.25 to 0.5 to 0.75 mg/m2) increased the incidence of severe toxicity from 0% to almost 40%, especially among older patients. These results support the usefulness of low-dose GM-CSF (0.25 mg/m2) in stimulating marrow recovery in selected patients with adequate marrow reserve treated with high-dose melphalan for refractory multiple myeloma.

Granulocyte-macrophage colony stimulating factor (GM-CSF) after high-dose melphalan in patients with advanced colon cancer.

Nine patients with progressive, metastatic disease from primary carcinoma of the colon were entered into a phase I/II study using continuous intravenous infusions of granulocyte-macrophage colony-stimulating factor (GM-CSF) and high dose melphalan (120 mg m-2). GM-CSF was given alone to six patients during the first part of the study to determine a dose that would produce a peripheral leucocyte count (WCC) greater than or equal to 50 X 10(9) 1(-1) and was initially given at 3 micrograms kg-1 day-1 and escalated to 10 micrograms kg-1 day-1 after 10 days. The infusion was discontinued when the WCC exceeded 50 X 10(9) 1(-1) and after a gap of one week, melphalan was given over 30 min. GM-CSF was recommenced 8 h later and was continued until the neutrophil count had exceeded 0.5 X 10(9) 1(-1) for greater than 1 week. One patient achieved a WCC greater than 50 X 10(9) 1(-1) with GM-CSF 3 micrograms kg-1 day-1, but the other five who entered this phase of the study required dose escalation to 10 micrograms kg-1. No toxicity attributed to GM-CSF was seen. After melphalan, the median times to severe neutropenia (less than 0.5 X 10(9) 1(-1] and thrombocytopenia (greater than 20 X 10(9) 1(-1] were 6 and 9 days respectively. The median durations of neutropenia and thrombocytopenia were 14 and 10 days respectively. All patients required intensive support with a median duration of inpatient stay of 24 days. There was one treatment related death due to renal failure. One complete and two partial remissions (33% response rate) were seen but these were of short duration (median of 10 weeks). This study demonstrates that GM-CSF given by continuous intravenous infusion produces significant increments of peripheral granulocyte counts at 3 and 10 micrograms kg-1 day-1 and is not associated with any toxicity. The duration of neutropenia and thrombocytopenia induced by high-dose melphalan appears to be reduced by the subsequent administration of GM-CSF to times which are at least as short as have been reported in historical series which have used autologous bone marrow rescue.

Phase I study of intravenously administered bacterially synthesized granulocyte-macrophage colony-stimulating factor and comparison with subcutaneous administration.

A Phase I study of bacterially synthesized recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) was undertaken in 21 patients with advanced malignancy or neutropenia. rhGM-CSF was administered once daily by i.v. bolus injection (0.3 to 3 micrograms/kg/day) or 2-h i.v. infusion (3 to 20 micrograms/kg day) for 10 days. rhGM-CSF at all i.v. doses caused an immediate transient decrease in circulating neutrophils, eosinophils, and monocytes. By 6 h after rhGM-CSF, circulating leukocyte levels were restored. Daily i.v. bolus dosing (0.3 to 3 micrograms/kg/day) did not elevate leukocyte levels except in one neutropenic patient. Daily 2-h i.v. infusions (10 to 20 micrograms/kg/day) caused a dose-dependent leukocytosis with increased levels of neutrophils (up to 4.3-fold), eosinophils (up to 18-fold), and monocytes (up to 3.5-fold). Marrow aspirates showed increased proportions of promyelocytes and myelocytes during rhGM-CSF administration. Retreatment after 10 days without rhGM-CSF resulted in a more marked leukocytosis at doses greater than or equal to 10 micrograms/kg/day. Platelet levels decreased for the first 3 days and then increased during the first course of rhGM-CSF administration. Two patients with chronic lymphocytic leukemia had a transient reduction in lymphocytosis. Serum cholesterol and albumin levels decreased, and vitamin B12 levels increased during rhGM-CSF treatment. At doses of up to 15 micrograms/kg/day, rhGM-CSF was relatively well tolerated by the patients, but adverse effects included bone pain, lethargy, fever, rash, and weight gain. A first dose reaction characterized by hypoxia and hypotension was identified at dose levels greater than or equal to 1 microgram/kg. Dosing i.v. was less potent at inducing a leukocytosis than previously observed for equivalent s.c. doses and was associated with a higher incidence of generalized rash and first dose reactions. The maximal tolerated dose of i.v. rhGM-CSF was 15 micrograms/kg/day. Phase II studies in which the derived effect is to raise leukocyte levels should be undertaken at rhGM-CSF doses of 3 to 15 micrograms/kg/day.

Clinical studies with recombinant human granulocyte-macrophage colony-stimulating factor.

Recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) has been used in two clinical studies at the Christie Hospital in Manchester, United Kingdom. Short daily "bolus" injections (over 30 min) were associated with serious toxicity which included bone pain, pruritus and pericarditis. In contrast, continuous infusions did not cause any toxicity and produced significantly higher increments of the peripheral neutrophil counts. rhGM-CSF reduced the period of life-threatening neutropenia following high-dose i.v. melphalan (120 mg/m2). Also, rhGM-CSF shortened the duration of thrombocytopenia induced by this chemotherapy to less time than has been seen historically in conjunction with autologous bone marrow rescue.

Subcutaneous granulocyte-macrophage colony-stimulating factor in patients with myelodysplastic syndrome: toxicity, pharmacokinetics, and hematological effects.

The toxicity, pharmacokinetics, and hematologic effects of granulocyte-macrophage colony-stimulating (GM-CSF) were studied in a phase I/II trial of 16 patients with myelodysplastic syndrome (MDS). The GM-CSF was administered subcutaneously (SC) daily so as to achieve prolonged blood levels and to establish an outpatient treatment regimen. Four dose levels were administered for ten days: 0.3 microgram/kg/d (three patients), 1.0 microgram/kg/d (three), 3.0 micrograms/kg/d (four), and 10.0 micrograms/kg/d (six). The most common toxicities were fever and a flu-like syndrome, which were dose-dependent. The maximum-tolerated dose was 10.0 micrograms/kg/d, which induced severe rigors (two patients), fever greater than 40 degrees C (one), severe bronchospasm (one), and WBC 60,000 (one). In one patient, refractory anemia with excess blasts in transformation (RAEB-T) progressed to acute nonlymphocytic leukemia after two doses of GM-CSF, and the patient died of leukemia that did not respond to chemotherapy. After doses of 3.0 and 10.0 micrograms/kg, serum GM-CSF levels peaked at 3.8 to 6.3 hours, and persisted for 14 and 24 hours, respectively. Circulating granulocytes (neutrophils and bands) increased in a dose-dependent manner, as 11 of 13 patients who received greater than or equal to 1.0 microgram/kg/d responded with a two- to 194-fold increase. Although the neutrophils usually returned to pretreatment levels shortly after stopping GM-CSF, two patients continue to exhibit an elevation of neutrophils for 6 months. Dose-related increases in circulating monocytes and eosinophils were also noted. Transient increases in platelet and reticulocyte counts were observed in two and three patients, respectively. Five of the 16 patients later received maintenance GM-CSF at 3 micrograms/kg/d for 2 to 9 weeks. All showed a dramatic increase in neutrophils after 2 weeks. Thereafter, despite continued therapy, the neutrophil count in four patients declined markedly. In conclusion, GM-CSF is well tolerated by the SC route and induces striking, but usually temporary, improvement in the neutropenia of MDS. Larger prospective phase III trials will determine the duration of hematologic responses and the impact on infection, morbidity, and mortality.

Effects of bacterially synthesized recombinant human granulocyte-macrophage colony-stimulating factor in patients with advanced malignancy.

STUDY OBJECTIVE: To define the clinical and hematologic effects of subcutaneously administered bacterially synthesized recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF). DESIGN: Single arm nonrandomized dose escalation study. PATIENTS: Twenty-one patients with advanced malignancy who were not receiving concurrent myelosuppressive therapy. INTERVENTIONS: Subcutaneous administration of rhGM-CSF by once-daily injection to groups of two to four patients at doses of 0.3 to 30 micrograms/kg body weight.d for 10 consecutive days. Some patients received a second 10-day period of daily rhGM-CSF treatment after a 10-day nontreatment interval followed by alternate-day treatment. Clinical status and hematologic values were monitored frequently. MEASUREMENTS AND MAIN RESULTS: All doses of rhGM-CSF caused an immediate transient fall of 84% to 99% in circulating neutrophils, eosinophils, and monocytes. Continued daily dosing caused a leukocytosis of up to 10-fold with increases in numbers of circulating neutrophils, eosinophils, monocytes, and lymphocytes. There appeared to be a plateau in the increase in neutrophils in the dose range 3 to 15 micrograms/kg.d. Marrow aspirates showed increased proportions of promyelocytes and myelocytes. Alternate-day injection of 15 micrograms/kg maintained a leukocytosis. At doses up to 15 micrograms/kg.d, rhGM-CSF was well tolerated but adverse effects included bone pains, myalgias, rashes, and liver dysfunction. At doses exceeding 15 micrograms/kg.d, pericarditis was a dose-limiting toxicity. Idiopathic thrombocytopenic purpura was reactivated by rhGM-CSF in one patient. CONCLUSIONS: Bacterially synthesized rhGM-CSF induces a leukocytosis in the dose range of 3 to 15 micrograms/kg.d. These doses are appropriate for phase II studies.

Recombinant human granulocyte macrophage colony stimulating factor (rhGM-CSF) given as daily short infusions--a phase I dose-toxicity study.

Twenty patients with progressive metastatic solid tumours were entered into a study to evaluate the biological effects and toxicity of recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF). GM-CSF was given as half-hour intravenous infusions during two 10-day phases of daily treatments (separated by 10 days without GM-CSF) and over a final phase of 20 days of alternate day infusions. Doses were escalated in steps from 0.3 to 60 micrograms kg-1 day-1 between successive patient groups. Significant increases (P less than 0.005) of total leucocyte, neutrophil and eosinophil polymorph counts were seen over the periods of daily infusions (up to four-fold rises of total white count) at dose levels of 10 micrograms kg-1 and above. Counts produced at 30 micrograms kg-1 were significantly higher than at 10 micrograms kg-1 (P less than 0.025). Toxic side effects of GM-CSF included mild transient pyrexias, bone pain and pruritus. The maximum tolerated dose was 60 micrograms kg-1, which produced severe toxicity in 80% of patients. The toxicity at this dose included pericarditis and dyspnoea ascribed to a 'capillary-leak' syndrome. One patient receiving 60 micrograms kg-1 died as a result of a pulmonary embolus. Seven patients with previously rapidly progressive metastatic tumours experienced stabilisation of disease while receiving GM-CSF and one patient with a previously heavily pretreated metastatic soft tissue sarcoma underwent a greater than 50% reduction of tumour volume. Patients undergoing chemotherapy may benefit both from a reduction of the myelosuppressive effects of cytotoxic agents and from an antitumour effect if GM-CSF is incorporated into future regimens.

A prospective randomized trial of alpha 2B-interferon/gamma-interferon or the combination in advanced metastatic renal cell carcinoma.

Eighty-nine patients with advanced measurable metastatic renal cell carcinoma were entered into a prospective randomized trial comparing alpha-interferon to gamma-interferon and to the combination. The trial was performed in order to confirm the activity of gamma-interferon and assess the potential clinical synergism. Response rates were 5, 10, and 5%, respectively. The low response rate may have been due to the inability to raise the doses of the interferons to higher levels. Clinical synergy at this dose, route, and schedule of administration in renal cell carcinoma does not exist.

Phase I-II trial of interferon-alpha 2b by continuous subcutaneous infusion over 28 days.

Interferon-alpha 2b (IFN-alpha) was administered by continuous subcutaneous (s.c.) infusion to 23 patients with hematologic malignancies or metastatic solid tumors: 5 patients with multiple myeloma, 3 with malignant melanoma, 2 with chronic myelogenous leukemia (CML), 10 patients with renal cell cancer, and 3 patients with other solid tumors. Drug was delivered by continuous s.c. infusion for 28 days (1 cycle) at daily dose levels of 0.7, 1.4, 2.5, 3.6, or 5.0 X 10(6) IU/m2 to 3, 3, 3, 8, and 6 patients, respectively. At the highest dose level, a severe flu-like syndrome was seen in 3 patients and severe gastrointestinal toxicity in 2 patients. The maximally tolerated dose (MTD) was 3.6 X 10(6) IU/m2.day and the principal toxicity was a mild to moderate flu-like syndrome. Local skin reactions were occasionally noted at all dose levels if the s.c. needle site was not rotated every 3-4 days. At dose levels of 2.5-3.6 X 10(6) IU/m2.day, IFN-alpha serum levels at steady state ranged from 19 to 61 IU/ml. The time to achieve steady-state conditions ranged from 40 to 72 h and at steady state, 24 h area under the concentration time curve (AUC24 h) ranged from 480 to 1,464 IU/ml.h. Objective responses were seen 3 of 17 evaluable patients: 1/7 in renal cell cancer (14%); 1/2 in CML and in one patient with ependymoma. Remissions lasted 4, 8, and 15 months in renal cell, CML, and ependymoma, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)