Cost-benefit analysis of interferon alfa-2b in treatment of hairy cell leukemia.

The clinical benefits as well as the cost benefits of use of recombinant interferon (IFN) alfa-2b instead of conventional chemotherapy (primarily chlorambucil) for progressive hairy cell leukemia were assessed retrospectively on the basis of 12 months of clinical data from 128 patients treated with IFN alfa-2b. Data from 71 matched historical control patients who had received conventional treatment were used for survival analysis. Hematologic response (reversal of cytopenias) was achieved by 18% of the control patients versus 73% of the IFN-treated patients. This response was associated with virtual elimination of the need for transfusions and splenectomy as well as dramatic decreases in the frequency of fatal infections (22.5% vs. 1.6%) and the 12-month mortality rate (28% vs. 3.1%). Direct costs per patient per year for medical care (transfusions, antibiotic treatment, splenectomy, and chemotherapy) of those receiving IFN alfa-2b were 2.8-fold lower than costs for medical care of control patients ($5,027 vs. $14,046). Indirect costs, which reflect the present value of future earnings lost due to premature death, were 13.3-fold lower for IFN-treated patients than for control patients ($4,771 vs. $63,507). Our analysis demonstrates that IFN alfa-2b offers substantial clinical and cost advantages to patients with hairy cell leukemia and that the introduction of this therapy using novel biotechnology furthers the health care community's commitment to cost containment.

Role of cytoplasmic lipids in altering diphenylhexatriene fluorescence polarization in malignant cells.

Prior studies of fluorescence anisotropy (polarization) with diphenylhexatriene in normal and malignant cell populations have shown differences which have been attributed to an altered membrane lipid composition in cancer. We studied fresh tumor cells from patients with diverse lymphoid neoplasms and found a discrete range of whole-cell fluorescence polarization values (P values) for each type of neoplasm. Following cell fractionation, however, the P values of isolated plasma membranes from malignant cells did not differ significantly from the values obtained with normal donor lymphocytes. Therefore, the altered whole-cell fluorescence polarization measurements in malignant cells are not likely to be due to gross lipid changes in the plasma membrane. Histochemical staining and cell fractionation revealed the presence of cytoplasmic lipid accumulations, and these had extremely low P values, which could account for the low P values of malignant cells. Complementary studies of lymphoid cell lines showed whole-cell fluorescence polarization measurements to be extremely sensitive to exogenous lipid supplements, but membrane values remained stable. We conclude that alterations in membrane lipid fluidity, as measured by the diphenylhexatriene probe, are not consistently found in lymphoid neoplasms and hence cannot presently be invoked to account for the malignant behavior of these cells. However, intracellular neutral lipid accumulation appears to be a common feature of the lymphoid neoplasm. The lipid alterations described could be characteristic of cell immaturity or proliferation rather than malignancy; nevertheless, they may convey unappreciated biological consequences.

Phase I study of alpha 2-interferon plus doxorubicin in patients with solid tumors.

Cytotoxic chemotherapy and interferon have shown synergistic antitumor activity in vitro. The purpose of this study was to determine the maximally tolerated dose of doxorubicin given every 3 weeks, in patients receiving recombinant alpha 2-interferon [10 X 10(6) IU/m2 s.c. three times per week (Monday, Wednesday, and Friday)] during the first 2 weeks of each cycle of doxorubicin. Fourteen patients received a total of 41 cycles. Hematological toxicity was dose limiting with granulocytopenia (total granulocyte count, less than 1000) occurring in 50% of patients treated with doxorubicin at 40 mg/m2 and in 25% of patients treated with doxorubicin at 30 mg/m2. Nonhematological toxicities included a flu-like syndrome, alopecia, nausea, vomiting, diarrhea, and transient mild increases in liver function tests. A partial response was seen in one patient with metastatic squamous cell carcinoma of the skin and in another patient with metastatic adenocarcinoma of the pancreas. Concomitant administration of recombinant alpha 2-interferon given on this schedule limits the amount of doxorubicin that can be administered. However, the responses noted in this study are encouraging enough to warrant additional studies of doxorubicin plus recombinant alpha 2-interferon.

Phase I clinical trial of 9,10-anthracene dicarboxaldehyde (Bisantrene) administered in a five-day schedule.

Bisantrene is a substituted anthracene derivative which preclinically demonstrated a spectrum of activity similar to that of doxorubicin but without associated cardiotoxicity. A Phase I evaluation of the drug has been performed using daily i.v. administrations for 5 days. Sixty courses of treatment were administered to 23 patients at doses from 2.5 to 90 mg/sq m/day. Courses were repeated at 4-week intervals. Dose-limiting toxicities were leukopenia and local cutaneous reactions. The leukopenia was dose related, noncumulative, and of brief duration. Local reactions occurred in 14 of 37 courses administered at doses greater than 60 mg/sq m and in 13 patients resulted in clinical cellulitis of the infused extremity. Gastrointestinal side effects were mild. No alopecia or cardiotoxicity was observed. Two mixed responses were obtained in patients with hypernephromas. Using a daily schedule for 5 days, approximately 40% more drug can be delivered per course than by single-day i.v. administration. However, with this schedule, local cutaneous reactions may prove additionally dose limiting. Phase II studies of Bisantrene in a daily i.v. schedule for 5 days are planned at a dose of 80 mg/sq m/day to be repeated every 4 weeks.

Phase I trial of escalating dose doxorubicin administered concurrently with alpha 2-interferon.

The clinical use of alpha 2-interferon and doxorubicin is based on in vitro and preclinical in vivo observations of synergistic antitumor efficacy. To test this combination a Phase I clinical and pharmacokinetic study of the concurrent use of alpha 2-interferon and doxorubicin was initiated in patients with malignant solid tumors. Each 5-wk treatment cycle consisted of 3 wk of drug administration and 2 wk of rest. The alpha 2-interferon was administered s.c. at a constant dose of 10 million IU/m2 on Mondays, Wednesdays, and Fridays in all patients while the doxorubicin was administered weekly beginning with a dose of 5 mg/m2 and escalated to the maximum tolerated dose of 25 mg/m2. At least three evaluable patients were entered at each dose level, and no dose escalations were allowed within patients. The dose-limiting toxicities were granulocytopenia and thrombocytopenia. Hepatic enzyme elevations and systemic symptoms due to interferon occurred at all dose levels. None was severe or dose limiting, and all were reversible. These toxicity data suggest that the hepatotoxic effects of interferon do not enhance doxorubicin toxicity when given by this dose and schedule. Doxorubicin plasma levels were measured at each dose level. The recommended dose of doxorubicin is 25 mg/m2 per wk when administered with 10 million IU/m2 of interferon in this schedule. This schedule allows for the administration of a greater total dose of doxorubicin than has been achieved when given every 3 wk with the same dose and schedule of alpha 2-interferon in a parallel study.

Phase II study of recombinant alpha-2 interferon in resistant multiple myeloma.

A multicenter phase II study of INTRON, recombinant alpha-2 interferon (Schering Corp, Kenilworth, NJ), in patients with relapsing or refractory myeloma was initiated. Patients received either intravenous therapy for two weeks followed by subcutaneous therapy or subcutaneous dosing from initiation of treatment. Of 38 evaluable patients, 19 were refractory and 19 had relapsed at entry. Twenty-five of 38 had received prior treatment with multiple drugs. Responses were seen among 2/19 refractory patients and 5/19 relapsing patients. Three of seven responders continue to respond for more than one year while receiving maintenance therapy. Most patients experienced improvement in bone pain, and one patient, with a complete response, had healing of bone lesions. Survival curves show a statistically significant improvement in survival for responders v nonresponders. INTRON was well-tolerated with only four patients discontinuing treatment due to adverse effects. Thirty-two percent of patients had hematologic toxicity requiring dose adjustment; however, there was no evidence of cumulative hematologic toxicity. No patients developed serum neutralizing factors to interferon. Additional trials are warranted to study the activity of INTRON in previously untreated patients.

A phase I clinical trial of recombinant DNA gamma interferon.

Recombinant gamma interferon (r-GIFN) demonstrates in vitro and in vivo characteristics that contrast with those of alpha and beta interferons. It has relatively weak antiviral properties, yet relatively potent immunomodulatory effects. A phase I trial was performed with r-GIFN (specific activity 2.6 X 10(6) IU/mg protein), administered as a continuous intravenous (IV) infusion over 24 hours for five days (Cl X 5) and repeated every 28 days. This schedule was chosen based on the short half-life of r-GIFN in animal systems and the in vitro augmentation of biologic effects with continuous exposure to interferons. Twenty-one patients with refractory solid tumors received 46 evaluable courses of therapy. The dose-limiting toxicities included fever, flu-like symptoms, cardiovascular toxicity, and neurotoxicity. The cardiovascular toxicity included hypotension and one episode of cardiac ischemia with chest pain. Neurotoxicity consisted of lethargy and confusion. These toxicities were reversible, and although dose-limiting, occurred sporadically throughout all dosage levels. Mild to moderately severe non-dose-limiting toxicities included nausea and vomiting, leukopenia, and liver function abnormalities. Other infrequent toxicities included hypocalcemia, diarrhea, constipation, and alopecia. The maximally tolerated dose of r-GIFN on this schedule is 0.5 X 10(6) IU/m2/d. Partial responses were seen in one patient with metastatic melanoma and in one patient with renal cell carcinoma. Toxicity and antitumor activity were seen at doses where interferon serum levels could not be detected by radioimmunoassay. In addition, the toxicity and antitumor activity seen were at much lower doses than previously described for shorter infusion schedules of other recombinant gamma interferon preparations. Differences in biologic activity of interferon preparations and/or differences in scheduling may account for this variability. Although this study defines a recommended phase II dose of r-GIFN based on the maximally tolerated dose, the optimal therapeutic index may exist at a lower dosage level.

Renal and metabolic complications of undifferentiated and lymphoblastic lymphomas.

The early metabolic events in 33 patients with non-Hodgkin lymphoma were analyzed in the present study. Twenty-three patients had Burkitt lymphoma, 3 had non-Burkitt undifferentiated lymphoma and 7 had lymphoblastic lymphoma. Eight patients developed azotemia prior to starting chemotherapy while five did so during the first treatment week. All the patients but two who developed azotemia had stage C or D disease. Serum LDH prior to chemotherapy correlated well with the stage of disease and predicted the serum levels of creatinine, uric acid and phosphorus in the post-treatment period. Surgical excision of the main tumor mass was associated with a low incidence of azotemia and other metabolic derangements. Hyperuricemia and occasionally obstruction were encountered as the causes of azotemia in the pre-treatment period. Hyperuricemia and/or hyperphosphatemia were presumed responsible for the development of azotemia in the post-chemotherapy period. Two patients were dialyzed for renal failure due to hyperuricemia and one for renal failure due to hyperphosphatemia which developed shortly after starting chemotherapy. The patterns of renal and metabolic disturbances observed during treatment of these patients were characterized by the following profiles: 1. Azotemia due to hyperuricemia prior to treatment. 2. Hyperuricemia without azotemia in the pre-treatment period with azotemia due to hyperphosphatemia in the post-treatment period. 3. Azotemia due to combined hyperphosphatemia and hyperuricemia developing gradually in post-treatment period. 4. Increased urine phosphorus excretion in both non-azotemic and azotemic patients.

Intron A (interferon alfa-2b): clinical overview and future directions.

The clinical development of the recombinant alpha interferons represents a prototype for the clinical development of biological compounds. Their testing raises fundamental questions concerning phase I objectives and strategies for biologicals, eg, study design in an immune model v a cytotoxic model. However, with over 5,000 patients treated with these compounds, some general principles have emerged. There is a suggestion of dose-response relationships, and a clearer picture of schedule dependence. The extent of tumor burden and identification of sensitive subtypes of patients also appear to be critical factors in evaluating the true potential activity of biological compounds. The toxicity profile of the alpha interferons is unusual. Fever and flu-like symptoms occur almost universally in all doses and schedules, and are usually dose-limiting. Somnolence and other CNS effects occur in a small percentage of patients. Hematologic toxicity occurs but is minimal at lower doses and is noncumulative and rapidly reversible at all doses. Gastrointestinal toxicity is mild. No other unusual or unexpected toxicities have been reported, and early reports of cardiovascular toxicity have not been confirmed in large trials. The use of these pioneer recombinant DNA products raised concerns about the potential production of antibodies and serum-neutralizing factors. Reports with small patient numbers confirmed the occasional development of serum-neutralizing activity to some alpha interferons, which may coincide with a loss of detectable serum interferon and loss of clinical activity. A large study with interferon alfa-2b (Intron A) has reported a low overall incidence of neutralizing activity (2.5%) and no association with loss of clinical activity. The significance of the neutralizing activity and the reasons for an apparently higher incidence of this phenomenon with other alpha interferon preparations remain to be determined. The full role of alpha interferon by itself or in combination with other available therapies will be resolved in coming years. Efficacy data available to date and phase I combination studies are reviewed.

The alpha interferons: clinical overview.

The clinical development of the recombinant alpha interferons has provided a prototype for the clinical development of biological compounds. With over 5,000 patients now treated with these compounds, some general principles have emerged that have wider implications for phase I-II strategies for testing other biologicals. There is a suggestion of dose-response relationships and a clearer picture of schedule dependence. The extent of tumor burden and identification of sensitive subtypes of patients also appear to be critical factors in evaluating the true potential activity of biological compounds. The toxicity profile of the alpha interferons is unusual. Fever and flu-like symptoms occur in all doses and schedules and are usually dose limiting. Somnolence and other CNS effects occur in a small percentage of patients. Hematologic toxicity occurs but is minimal at lower doses and is noncumulative and rapidly reversible at all doses. Gastrointestinal toxicity is mild. No other unusual or unexpected toxicities have been reported, and early reports of cardiovascular toxicity have not been confirmed in large trials. The use of these pioneer recombinant DNA products raised concerns about the potential development of antibodies and serum-neutralizing factors. Reports with small patient numbers confirmed the occasional development of serum-neutralizing activity to some alpha interferons. The significance of this neutralizing activity and the reasons for an apparent higher incidence of this phenomenon with some alpha interferon preparations remain to be determined. The full role of alpha interferon by itself or in combination with other available therapies will be resolved in coming years. This review presents current safety, efficacy, and neutralizing antibody data.

Low incidence of serum neutralizing factors in patients receiving recombinant alfa-2b interferon (Intron A).

The development of serum neutralizing factors against recombinant alfa-2b interferon (Intron A) was reviewed in a large clinical experience. In 537 patients receiving systemic therapy, neutralizing factors developed in only 13 (2.4 percent). In 1,326 patients who received intranasal administration and 154 with intralesional administration, the incidence was less than 1 percent. Patients in whom antibody developed had no predisposing characteristics that could be identified, no particular types of patients with cancer had a high rate of neutralizing factors, and two of 10 patients with cancer in whom neutralizing factor developed were still able to show clinical responses. In patients in whom neutralizing factor was present, there was no discernible difference in the incidence or severity of interferon side effects as compared with patients who had no demonstrable neutralizing factor levels. This form of recombinant alpha-2 interferon appears to have a very low antigenic potential.

Plasma lipid alterations in leukemia and lymphoma.

Plasma lipids and lipoproteins were studied at presentations in 25 patients with acute leukemia and non-Hodgkin's lymphoma. All patients demonstrated an abnormally in at least one plasma lipid fraction, and most exhibited a predictable pattern of lipid alterations that consisted of extremely low levels of high-density lipoprotein cholesterol (median [Xm] = 23), elevated triglyceride (Xm = 165) and elevated very-low-density lipoprotein (Xm = 26). Patients restudied during remission demonstrated a return to normal values. The degree of lipid abnormality was directly related to the underlying tumor burden and particularly to the presence of bone marrow involvement. However, even patients with minimal tumor bulk demonstrated plasma lipid abnormalities. The results suggest that an abnormality in systemic lipid metabolism, possibly in triglyceride clearance, is present in these patients and that its incidence in this population is high.

A three-dimensional finite-difference thermoregulatory model of a squirrel monkey.

A three-dimensional thermoregulatory model of a squirrel monkey, whose shape is approximated by 742 rectangular blocks of varying sizes, has been developed. The inhomogeneous model has four layers: a core, a composite layer of muscle and fat, skin, and fur. The model simulates the flow of heat into and out of the body, including internal heat generation (metabolism) by the body, cooling and distribution of heat by blood, thermal conduction throughout the body, evaporative heat loss from sweating, and radiation and convection from the outer surface of the body. It also simulates dynamic thermoregulatory behavior such as peripheral vasomotor responses (skin vasodilation and vasoconstriction) and variable sweating rates. Computed results are compared with available experimental data; the agreement is good, especially for ambient temperatures above 26 degrees C.

Fluorescence polarization as a parameter of plasma lipids in patients with hematologic malignancies.

Abnormal diphenylhexatriene fluorescence polarization measurements (FP values) of plasma have previously been reported in patients with hematologic malignancies. However, the biological significance of this measurement is unclear. We have prospectively studied plasma from 39 patients with leukemia and lymphoma as well as normal donors for total cholesterol, total triglyceride, and lipoprotein-cholesterol fractions, and correlated these values with measured FP values. Total triglyceride, very low density lipoproteins (VLDL), high density lipoprotein (HDL) levels, and FP values were all strongly correlated with clinical and biochemical measures of tumor burden and varied directly with the presence of malignancy. Although the presence of abnormal FP values was confirmed in patients with leukemia and lymphoma, it was not a particularly sensitive measure for minimal tumor and it appeared to correlate directly with other measures of lipids and cholesterol, particularly triglyceride. It is suggested that further studies of conventional plasma lipids and lipoproteins be pursued in order to elucidate the apparently pervasive alterations in lipid metabolism present in these patients.

Treatment of metastatic malignant melanoma with recombinant interferon alpha 2.

Fifty-nine patients with metastatic malignant melanoma were entered into a phase II trial of recombinant alpha-2 interferon given in a dosage of 10 million IU/M2 subcutaneously three times per week for one year. Forty-five of these were evaluable for response. Of five evaluable patients with ocular primaries, none responded to interferon treatment. Four of 40 patients (10%) with cutaneous primaries achieved complete remission, and 6 further patients (15%) had partial remissions for a combined response rate of 25%. Two patients remain in complete remission 15+ and 32+ months after starting treatment. Responses were limited to subcutaneous, lymph node and lung metastases. The treatment schedule was well tolerated with the majority of patients receiving more than 70% of their predicted doses. Flu-like symptoms were the most common side effect. No evidence of cumulative toxicity was seen. We conclude that interferon is an active agent in metastatic malignant melanoma of cutaneous origin and that further trials are indicated.

Alpha interferons: a clinical overview.

The development of the recombinant alpha interferons has provided a prototype for the clinical development of biological compounds. Over 5,000 patients have now been treated with alpha interferons, and from this experience, some general principles relating to the phase I-III testing of biologicals have emerged. Clinical trials of alpha interferon have suggested dose-response relationships and provided a clearer picture of schedule dependence. These trials have also indicated that the extent of tumor burden and identification of sensitive patient subtypes may be critical factors affecting the potential activity of biological compounds. Recent studies using interferon in the treatment of chronic viral hepatitis have also generated promising results, suggesting an even greater antiviral role for the drug. The toxicity profile of the alpha interferons is unusual. Fever and influenza-like symptoms occur in almost all patients at all doses and schedules, and are usually dose limiting. Somnolence and other generally mild CNS effects occur in a small percentage of patients. Hematologic toxicity occurs but is minimal at lower doses and is noncumulative and rapidly reversible at all doses. Gastrointestinal toxicity is mild. No other unusual or unexpected toxicities have been reported, and early reports of cardiovascular toxicity have not been confirmed in large trials. The full role of alpha interferon in antineoplastic and antiviral therapy will be resolved in the coming years. This review summarizes existing safety and efficacy data for the alpha interferons.

Complete remission induction with combined VBMCP chemotherapy and interferon (rIFN alpha 2b) in patients with multiple myeloma.

The purpose of this study was to evaluate a new regimen for the treatment of multiple myeloma based on alternating 3-week cycles of chemotherapy and interferon (rIFN alpha 2). In this prospective phase II clinical trial the Eastern Cooperative Oncology Group evaluated a regimen consisting of 2 cycles of VBMCP (Vincristine 1.2 mg/M(2) IV d1, BCNU 20 mg/M(2) IV d1, Melphalan 8 mg/M(2) PO dl-4, Cyclophosphamide 400 mg/M2 IV d1, Prednisone 40 mg/M(2) PO d1-7) followed by alternating 3-week cycles of VBMCP and rIFN alpha2 5 Mu/M(2) SC 3x/week. Treatment was administered for 2 years. Fifty-eight patients with previously untreated multiple myeloma were entered. Objective response (OR) required 50% decrease in M-protein with correction of severe anemia and no progression of skeletal disease. Complete remission (CR) was defined by disappearance of M-protein and normalization of the bone marrow morphology. Life table analysis was utilized to express survival and response duration. Fifty-four patients were evaluable. Objective response was seen in 80% of patients including CR in 30% (16 patients). The median response duration is 35 months, 46 months for patients with CR. The median survival is 42 months for all patients. Five year survival is 42%. Although 78% of patients had neutrophil nadirs <1000 x 10(9)/L, the incidence of severe infection was only 9%. These data demonstrate that VBMCP + interferon is an effective new regimen combining chemotherapy with a biological response modifier for the treatment of multiple myeloma. The incidence of CR is high, and the response and survival durations appear to be 1 year longer than usually seen with standard chemotherapy. A current ECOG randomized trial compares VBMCP + interferon with VBMCP alone.

Acne arthralgia.

A syndrome of arthralgia associated with one form of acne is described. Orthopaedic surgeons should be alert to the association of profound arthralgia and myalgia with this particular variant of acne vulgaris. Thirteen patients are described, all of whom are adolescent boys with a chronic moderately active acne which suddenly became extremely aggressive and toxic. The symptoms and signs included proximal arthralgia and myalgia, fever, elevated sedimentation rate, and altered immunoglobulins. Control of acne and conservative physical therapy resulted in complete resolution of the musculoskeletal complaints.

Comparison of finite-difference time-domain SAR calculations with measurements in a heterogeneous model of man.

A finite-difference time-domain technique was used to calculate the specific absorption rate (SAR) at various sites in a heterogeneous block model of man. The block model represented a close approximation to a full-scale heterogeneous phantom model. Both models were comprised of a skeleton, brain, lungs, and muscle. Measurements were conducted in the phantom model using an implantable electric-field probe and a computer-controlled data acquisition system. The calculation and measurement of SAR distributions were compared primarily in the head (including the neck) and chest. To obtain the necessary spatial resolution with the computer model, the head and neck were modeled with approximately 105,000 cells, while 86,000 cells were used to configure the chest. Planewave fields, polarized in the E orientation, were utilized to irradiate the models at an exposure frequency of 350 MHz. Reasonable correlation existed between the calculations and measurements.

Technical assessment of fuel cell operation on anaerobic digester gas at the Yonkers, NY, wastewater treatment plant.

This paper summarizes the results of a 2-year field test to assess the performance of a specially modified commercial phosphoric acid 200-kW fuel cell power plant to recover energy from anaerobic digester gas (ADG) which has been cleansed of contaminants (sulfur and halide compounds) using a patented gas pretreatment unit (GPU). Specific project goals include characterization of the fuel cell power plant emissions and verification of the GPU performance for removing sulfur contaminants. To remove halide contaminants from the ADG, a halide guard, consisting of a vessel with a metal oxide supported on alumina, was incorporated into the fuel cell reactant supply. This first-of-a-kind demonstration was conducted at the Yonkers, NY, wastewater treatment plant, a sewage processing facility owned and operated by Westchester County. Results have demonstrated that the ADG fuel cell power plant can produce electrical output levels close to full power (200 kW) with negligible air emissions of CO, NO(x), and SO(2). The GPU removed virtually 100% of H(2)S and 88% of organic sulfur, bringing the overall sulfur removal efficiency of the GPU to over 99%. The halide guard removed up to 96% of the halides exiting the GPU.