Background: Comparative studies with topical corticosteroids and antihistamines for treatment of allergic rhinitis have not always demonstrated clear distinctions between the two on the basis of therapeutic efficacy.Objective: This study was designed to compare the efficacy and tolerability of fluticasone propionate aqueous nasal spray with those of terfenadine in the treatment of seasonal allergic rhinitis.Methods: Three hundred forty-eight patients with allergic rhinitis were given fluticasone propionate aqueous nasal spray (200 mu g once daily), terfenadine tablets (60 mg twice daily), or placebo for 4 weeks in a multicenter, randomized, double-blind, double-dummy, parallel-group study.Results: Clinician-rated total nasal symptom scores after 1, 2, 3, and 4 weeks of therapy and patient-rated total nasal symptom scores throughout treatment were significantly (p < 0.05) lower in the fluticasone propionate group compared with the terfenadine group or the placebo group. Terfenadine was not statistically different from placebo on the basis of clinician-rated nasal symptom scores, except for sneezing. Total nasal airflow, measured by rhinomanometry, significantly (p < 0.05) improved in the fluticasone propionate group compared with the terfenadine group or the placebo group. More fluticasone propionate-treated patients compared with the place-treated patients has reduced nasal mucosal eosinophil counts after 4 weeks of therapy (p < 0.05). No serious or unusual drug-related adverse events were reported. Morning plasma cortisol concentrations after 4 weeks of therapy did not differ among groups.Conclusion: Fluticasone propionate aqueous nasal spray is more effective than terfenadine tablets for treatment of seasonal allergic rhinitis.
Background: Albuterol sulfate, in the syrup and tablet form for oral administration, has been an effective treatment for adults and children with bronchial asthma. Extended-release albuterol sulfate tablets (Proventil Repetabs, Schering Corp.) provide a convenient, twice-daily dosing regimen, but are indicated only for patients greater than or equal to 12 years of age.Objective: This study was undertaken to determine whether patients 6 to 12 years of age could be effectively and safely treated with extended-release albuterol tablets.Methods: This was a randomized, double-blind, placebo-controlled, parallel group study of 157 patients in five centers. Patients were randomized to 4 weeks' treatment with extended-release albuterol tablets, 4 mg twice daily (q 12h), increasing up to 12 mg q 12h, or placebo. Efficacy was evaluated based on pulmonary function tests (PFTs), physician and patient evaluations, and data collected from patients' diaries on PEFR, asthma symptoms, number of nighttime awakenings, and number of tablets taken. The primary efficacy parameter was area under the curve (AUG) for FEV(1), evaluated for 8 to 12 hours post-dosing. Safety was evaluated based on vital signs, electrocardiograms, and adverse events.Results: Mean AUCs for FEV(1) were significantly greater in the albuterol group at days 1 and 8 (P less than or equal to .03). The albuterol group showed consistently lower severity scores for asthma symptoms. Physicians' and patients' global evaluations favored the albuterol group over the placebo group. No serious, treatment-related adverse events were reported. There were no clinically meaningful changes from baseline in either treatment group for vital signs or electrocardiograms.Conclusions: Extended-release albuterol tablets (4 mg), administered to children 6 to 12 years old in divided doses of up to 24 mg/day, improved pulmonary function and asthmatic symptoms and were well tolerated.
This study examined the ability of fluticasone propionate aerosol to reduce oral prednisone requirements in patients with severe asthma. Ninety-six patients dependent on oral prednisone were treated for 16 wk with placebo or fluticasone propionate aerosol (750 or 1,000 micrograms twice daily). Their dosage of oral prednisone was adjusted weekly according to predetermined criteria. A total of 69% and 88% of patients treated with fluticasone propionate 750 and 1,000 micrograms twice daily, respectively, compared with 3% of placebo-treated patients used no prednisone by the end of the study. In the fluticasone propionate groups, FEV1 and peak expiratory flow rates at the last evaluable visit/date improved and the number of night awakenings and symptomatic albuterol use declined relative to placebo values (p < 0.05). Patient-rated asthma symptoms improved in the groups receiving fluticasone propionate but not in the placebo group (p < 0.005). Fluticasone propionate aerosol was well-tolerated, and it improved some dimensions of health-related quality of life measured using a standard patient survey. Fluticasone propionate aerosol (750 or 1,000 micrograms twice daily) effectively and safely allowed most asthmatics dependent on oral corticosteroids to reduce or eliminate oral prednisone use while improving pulmonary function and quality of life.
Immunotoxins--toxins covalently conjugated to specific antibodies--have been studied as possible agents in the treatment of cancer. The avid binding of IgE antibodies to FcR on mast cells and basophils suggested the possible use of an IgE-immunotoxin in the treatment of malignant mastocytosis or as a method to generate mast cell-depleted animals for study. To this end, the effect of a covalent conjugate of rat myeloma IgE and ricin A chain on rat cutaneous mast cells was examined in vivo. IgE-ricin A chain was capable of binding to and sensitizing cutaneous mast cells in vivo as indicated by a bluing response to intracutaneous anti-ricin A chain. IgE-ricin A chain, given either as a single dose or, even more effectively, as two split doses, significantly reduced cutaneous histamine content for 6 to 8 days. Neither a mixture of IgE and ricin A chain that were not conjugated nor the induction of cutaneous mast cell degranulation with anti-IgE affected cutaneous histamine levels. Therefore, IgE-ricin A chain produces a prolonged depletion of cutaneous histamine levels.
In order to develop a reagent capable of killing cells with high-affinity IgE Fc receptors, such as mast cells and basophils, ricin A-chain (the toxic portion of ricin) was conjugated to rat IgE myeloma protein, IR 162, via derivatization of the IgE by n-succinimidyl-3-(2-pyridyldithio)propionate (SPDP) thus creating an IgE-immunotoxin. Monensin (10(-7)-10(-8)M), a carboxylic ionophore, facilitated IgE-ricin A-chain (3 X 10(-7)M) toxicity in a dose-related fashion ith significant reductions in [3H]leucine incorporation compared to cells exposed only to monensin. This enhanced toxicity could be inhibited by the addition of both anti-ricin A-chain or anti-IgE, suggesting that different routes of intracellular processing may play a role in determining the toxicity of the IgE-ricin A-chain conjugate. Ricin B-chain (5 X 10(-7) and 5 X 10(-8)M) added to free ricin A-chain (10(-6)-10(-8)M) reproducibly facilitated toxicity, and this toxicity could be inhibited (30-90%) by lactose (50 mM). Ricin B-chain also facilitated IgE-ricin A-chain (2.75 X 10(-8)M) toxicity; however, this toxicity was not affected by lactose. The data suggest that ricin B-chain potentiates the cytosolic access of internalized IgE-immunotoxin and that the binding and internalization of the toxin was mediated via the IgE Fc receptor. A second type of IgE-ricin A-chain conjugate was synthesized whereby both IgE and ricin A-chain were derivatized with SPDP. RBL cells were killed in a dose-dependent manner by this IgE-ricin A-chain conjugate (2.5 X 10(-6)-2.5 X 10(-9)M) without requiring the addition of monensin or ricin B-chain. These data indicate that the intracellular route and processing of internalized immunotoxin is critical to eliciting toxicity.
An IgE immunotoxin consisting of rat IgE myeloma protein, IR 162, conjugated via the heterobifunctional linking agent N-succinimidyl-3-(2-pyridyldithio)propionate to intact ricin was synthesized and evaluated. The capacity of this IgE-immunotoxin to bind to rat basophilic leukemia cells (RBL cells) and to inhibit RBL cell incorporation of [3H]leucine was assessed. The IgE-intact ricin conjugate sensitized RBL cells for histamine release after treatment with anti-IgE with a time-course of sensitization and dose-response equivalent to native IgE. Intact ricin and IgE-intact ricin were both cytotoxic to RBL cells as assessed by [3H]leucine incorporation. Lactose (50 mM) competed with intact ricin binding and toxicity such that more than 100 ng/ml ricin (8 times its IC50 in the absence of lactose) was required for ricin to kill RBL cells in the presence of lactose. Lactose (50 mM) was not able to fully inhibit 1-100 ng/ml IgE-ricin immunotoxin killing of RBL cells. Saturation of RBL cell IgE receptors by preincubation with IgE totally inhibited IgE-intact ricin-induced toxicity, in the presence of lactose, indicating that toxicity required IgE Fc receptor binding.
We observed immediate-type hypersensitivity reactions in 6 of 600 donors who underwent automated plateletpheresis procedures. Ethylene oxide gas, which was used to sterilize plastic components in the disposable apheresis kits, represented a possible source of sensitization. In skin-prick testing, 4 of the 6 donors who had had a hypersensitivity reaction and none of 40 controls who had not had such a reaction had positive tests when an ethylene oxide-human serum albumin reagent was used (P less than 0.001). Radioallergosorbent testing revealed that serum from 4 of the 6 donors who had reactions, but from only 1 of 145 controls, contained IgE antibodies to ethylene oxide-albumin (P less than 0.001). All six of the donors who had reactions had specific ethylene oxide-induced basophil histamine release (mean release [+/- SE], 34.2 +/- 5.6 percent), whereas none of four controls had specific histamine release in response to ethylene oxide (mean release, 5.7 +/- 1.2 percent; P less than 0.005). Repeat plateletpheresis in five of the donors who reacted was accompanied by a recurrence of mild allergic symptoms. These studies demonstrate that sensitization to ethylene oxide gas can occur in healthy plateletpheresis donors and that it may result in immediate hypersensitivity reactions during the donation. The prevalence of such reactions was 1.0 percent in our apheresis donor population.