Imiquimod 5% cream in the treatment of superficial basal cell carcinoma: results of a multicenter 6-week dose-response trial.

BACKGROUND: Superficial basal cell carcinoma (sBCC) is an increasingly common tumor in fair-skinned populations throughout the world. Imiquimod, an immune response modifier that induces cytokines including interferons, has been shown in preliminary studies to have an effect when applied topically to BCC. OBJECTIVE: We conducted a multicenter, randomized, open-label dose-response trial of imiquimod 5% cream in the treatment of primary sBCC assessing efficacy and safety of different dose regimens. METHODS: Ninety-nine patients were randomized to 6 weeks' application of imiquimod in 1 of 4 treatment regimens: twice every day, once every day, twice daily 3 times/week, once daily 3 times/week. The treatment site was excised and examined histologically 6 weeks after cessation of imiquimod. RESULTS: Intention-to-treat analysis revealed 100% (3/3) histologic clearance in the twice-daily regimen, 87.9% (29/33) clearance in the once every day regimen, 73.3% (22/30) clearance in the twice-daily 3 times/week regimen, and 69.7% (23/33) clearance in the once-daily 3 times/week regimen. Dose-related inflammatory skin reactions at the site of application were common. The majority were well tolerated and only 1 patient withdrew from the trial as a result of a medication-related skin reaction. CONCLUSION: Imiquimod 5% cream appears to have potential as a patient-administered treatment option in sBCC.

Treatment of external genital warts in men using 5% imiquimod cream applied three times a week, once daily, twice daily, or three times a day.

BACKGROUND: Medical therapy for genital warts remains suboptimal. The topical interferon and cytokine inducer, imiquimod, has been proved effective for the treatment of external genital and perianal warts, but there is a substantial difference in the response rates between men and women. When 5% imiquimod cream is applied three times a week up to 16 weeks, approximately two thirds of women treated with imiquimod achieve complete clearance of genital warts, whereas only about one third of men clear completely. GOAL: This study was undertaken to determine whether more frequent application of topical imiquimod cream would improve the rate of genital wart clearance in men. STUDY DESIGN: A randomized treatment trial involving adult men with biopsy-proven genital warts was conducted at nine centers in the United States and Canada using four different application frequencies. RESULTS: Complete clearance rates during the 16-week treatment period were as follows for the different imiquimod treatment frequencies: three times a week (35 %), once daily (28 %), twice daily (24%), and three times a day (27%)(P = 0.88). The four treatment groups all showed comparable reductions in the total lesion area, with a median of more than a 90% reduction in the lesion area by the end of treatment. There was a significant increase in the incidence and severity of local skin reactions including erythema, vesicle formation, ulceration, and excoriation as the dosing frequency increased from three times a week to three times a day. CONCLUSIONS: In this study, the optimal dosage regimen was the approved three times a week regimen. More frequent application (up to three times a day) did not improve clearance and was associated with an increase in local adverse events.

S-nitrosoglutathione inhibits TNF-alpha-induced NFkappaB activation in neutrophils.

OBJECTIVE AND DESIGN: Cytokine expression is controlled by transcription factors including NFkappaB, which has recently been found to exist in human neutrophils. We previously showed that exogenous nitric oxide (NO) induces neutrophil apoptosis and hypothesized that this NO effect could be mediated by inhibition of NFkappaB activation. MATERIALS AND METHODS: Isolated human neutrophils were incubated with or without S-nitrosoglutathione (GSNO 0.1 mM-5 mM; Sigma) for 2 h. Neutrophils were either unstimulated or stimulated with TNFalphalpha or n-formyl methionyl leucine phenylalanine (fMLP). Viability was assessed by vital dye cytotoxicity assay. After nuclear extraction and measurement of protein concentration, NFkappaB binding was determined by electrophoretic mobility shift assay. Effects of GSNO on activation of IkappaB alpha, which inhibits intranuclear translocation of NFkappaB, were measured by Western immunoblot technique. For comparison, experiments were also performed in the presence of the NFkappaB inhibitor PDTC. RESULTS: TNFalpha increased nuclear NFkappaB activity compared to unstimulated neutrophils (p < 0.001, n = 5). GSNO (500 microM) decreased TNFalpha-induced NFkappaB activity (p<0.05) and inhibited NFkappaB activity whether given prior to or during TNFalpha exposure. IkappaB alpha was significantly degraded at 30 and 120 min of TNFalpha exposure compared to control neutrophils (p < 0.05). GSNO exposure (500 microM) inhibited IkappaB alpha degradation in the presence of TNFalpha. PDTC enhanced neutrophil cell death and DNA fragmentation, in association with decreased NFkappaB activity, similar to GSNO effects. CONCLUSION: Neutrophils possess NFkappaB activity that is increased by stimulation with TNFalpha. GSNO inhibits NFkappaB activity in association with inhibiting TNFalpha-induced degradation of IkappaB alpha. GSNO effects are similar to those seen with NFkappaB inhibition by PDTC. Inhibition of NF kappaB could represent a potential anti-inflammatory effect of GSNO.

Imiquimod 5% cream in the treatment of Bowen's disease.

BACKGROUND: Large-diameter lesions of Bowen's disease at sites such as the shin may be difficult to treat surgically and may require alternate treatment modalities. OBJECTIVE: We investigated whether imiquimod 5% cream, a topical immune response modifier that stimulates the production of interferon alfa and other cytokines, is an effective topical treatment for Bowen's disease. METHODS: This was a phase II, open-label study in 16 patients, treating a single biopsy-proven plaque of Bowen's disease that was 1 cm or larger in diameter, with once-daily self-application of imiquimod 5% cream for 16 weeks. A biopsy was performed on the treated area 6 weeks after the end of treatment, with patient follow-up at 3 and 6 months. Lymphocyte CD4/CD8 ratios were analyzed in pretreatment and posttreatment biopsy specimens by immunophenotyping the lymphocytic infiltrate. RESULTS: Sixteen patients with Bowen's disease lesions ranging from 1 to 5.4 cm in diameter (0.7-21.6 cm(2) in area) were treated. Fifteen of these lesions were on the legs, and one was on the shoulder. Fourteen of the 15 patients (93% per protocol analysis) had no residual tumor present in their 6-week posttreatment biopsy specimens. One patient died of unrelated intercurrent illness before a biopsy specimen could be obtained. The median CD4/CD8 lymphocyte ratio in pretreatment biopsy specimens was 2:1, and this was reversed to a median of 1:2.2 in the posttreatment specimens. Ten patients completed 16 weeks of treatment, but 6 patients ceased treatment early (between 4 and 8 weeks) because of local skin reactions. CONCLUSION: Imiquimod 5% cream appears to be an effective treatment for Bowen's disease on the lower limbs. The 93% positive treatment response in biopsy-proven cases (excludes patient who died from an intercurrent illness who did not undergo a posttreatment biopsy) compares favorably with other current treatment modalities. The dosing schedule and length of treatment for Bowen's disease require further evaluation.

Neutrophils induce apoptosis of lung epithelial cells via release of soluble Fas ligand.

Neutrophils release soluble Fas ligand (sFasL), which can induce apoptosis in certain Fas-bearing cell types (Liles WC, Kiener PA, Ledbetter JA, Aruffo A, and Klebanoff SJ. J Exp Med 184: 429-440, 1996). We hypothesized that neutrophils could induce alveolar epithelial apoptosis via release of sFasL. A549 pulmonary adenocarcinoma cells expressed surface Fas and underwent cell death (10 +/- 7% viability) and DNA fragmentation (354 +/- 98% of control cells) when incubated with agonistic CD95/Fas monoclonal antibody (P < 0.05). Coincubation with human neutrophils induced significant A549 cell death at 48 (51 +/- 9% viability; P < 0.05) and 72 h (25 +/- 10%; P < 0.05) and increased DNA fragmentation (178 +/- 42% of control cells; P < 0.05), with morphological characteristics of apoptosis. The addition of antioxidants did not inhibit apoptosis. sFasL concentrations were maximally increased in coculture medium at 24 h (4.9 +/- 0.7 ng/ml; P < 0.05). Neutrophil-induced A549 cell apoptosis was blocked by inhibitory anti-Fas (42 +/- 6% of control cells; P < 0.05) and anti-FasL monoclonal antibodies (29 +/- 3%; P < 0.05). Human neutrophils and Fas similarly affected murine primary alveolar epithelial cell bilayers, and caspase activation occurred in response to Fas exposure. We conclude that neutrophils undergoing spontaneous apoptosis induce A549 cell death and DNA fragmentation, independent of the oxidative burst, that is mediated by sFasL.

A randomized, controlled, safety study using imiquimod for the topical treatment of anogenital warts in HIV-infected patients. Imiquimod Study Group.

OBJECTIVE: To assess the safety of imiquimod, an immune response modifier, in the topical treatment of external anogenital warts in HIV-infected patients. SETTING: Clinical sites in the United Kingdom (eight) and the United States (five). DESIGN: A prospective, randomized, double-blind, vehicle-controlled study of imiquimod 5% cream or vehicle applied for 8+/-2 h three times per week for a maximum of 16 weeks in HIV-seropositive males (n = 97) and females (n = 3) aged 18 years or more with clinically diagnosed external anogenital warts, CD4 T lymphocyte count of > or = 100 x 10(6) cells/l and Karnofsky score > or = 70. MAIN OUTCOME MEASURES: Safety was assessed through the incidence and severity of local skin reactions and other adverse events, and through clinical laboratory tests. Wart clearance was documented by two-dimensional measurements of warts and by photography. RESULTS: Among the patients treated with imiquimod (n = 65) and vehicle (n = 35), the most common local skin reaction was erythema, (41.9 and 26.7%, respectively) and the incidence of patients reporting at least one adverse event was 69.2 and 65.7%, respectively. No clinically meaningful differences or changes in laboratory values were observed between treatment groups, nor were drug-related adverse effects observed in regard to HIV disease. While there was no significant difference between treatment groups in the number of patients who totally cleared their baseline warts (imiquimod 11% versus vehicle 6%, P = 0.488), more imiquimod-treated patients experienced a > or = 50% reduction in baseline wart area (38% versus 14%, P = 0.013). CONCLUSION: Most local skin reactions were mild and no adverse effects on HIV disease were observed. Topically applied imiquimod 5% cream reduced wart area and may have clinical utility in treating external anogenital warts in some HIV-infected patients.

Therapeutic response of basal cell carcinoma to the immune response modifier imiquimod 5% cream.

BACKGROUND: Basal cell carcinoma (BCC) responds to interferon therapy. Imiquimod is a cytokine and interferon inducer. OBJECTIVE: This randomized, double-blind pilot trial evaluated the safety and efficacy of imiquimod 5% cream versus vehicle in the treatment of BCC. METHODS: In this population of 35 patients with BCC, 24 received imiquimod 5% cream and 11 received vehicle cream in 1 of 5 dosing regimens for up to 16 weeks. Six weeks after treatment, an excisional biopsy of the target site was performed. RESULTS: BCC cleared (on the basis of histologic examination) in all 15 patients (100%) dosed twice daily, once daily, and 3 times weekly; in 3 of 5 (60%) patients dosed twice weekly; 2 of 4 (50%) dosed once weekly; and in 1 of 11 (9%) treated with vehicle. Adverse events were predominantly local reactions at the target tumor site, with the incidence and severity of local skin reactions declining in groups dosed less frequently. CONCLUSION: Imiquimod 5% cream shows clinical efficacy in the treatment of BCC.

Effects of exogenous nitric oxide and hyperoxia on lung fibroblast viability and DNA fragmentation.

Effective lung repair after acute injury requires elimination of proliferating mesenchymal and inflammatory cells without inducing an acute inflammatory response or disturbing concomitant repair of lung microvasculature. Previous studies have shown that endogenous NO regulates programmed cell death in fibroblasts and can modulate wound fibroblast synthetic function. We hypothesized that exposure of human lung fibroblasts to NO gas would decrease viability and induce apoptotic cell death. Primary cultures of normal human lung fibroblasts were exposed for 4 h to room air (RA), 80% oxygen, NO (at either 20 or 50 ppm) blended with RA, or NO blended with 80% O(2), then incubated for 24 to 72 h. Cell viability was determined by fluorescence viability/cytotoxicity assay and DNA fragmentation by TUNEL assay. Peroxynitrite formation was assessed using immunoblotting for S-nitrosotyrosine. NO plus O(2) induced significant cell death at 20 and 50 ppm NO when compared to either RA or O(2) alone at both 24 and 72 h (p < 0.05). Incubation with superoxide dismutase (SOD), catalase (CAT) or SOD + CAT significantly decreased cell death in fibroblasts treated with NO(20)/O(2) and NO(50)/O(2) compared with controls (p < 0.05). NO(20)/O(2) and NO(50)/O(2) exposure significantly increased TUNEL mean fluorescence intensity (MFI), consistent with increased DNA fragmentation, compared to RA at 24 and 72 h (p < 0.05). Antioxidants decreased MFI in cells exposed to NO(20)/O(2) (CAT and SOD + CAT) compared to controls at 24 h (p < 0.05). Western blot analysis for S-nitrosotyrosine showed increased signal intensity in fibroblasts exposed to NO at 20 and 50 ppm plus O(2) compared to RA or O(2) alone. Incubation with SOD + CAT reduced signal intensity for peroxynitrite in cells exposed to NO(20)/O(2). We conclude that NO in hyperoxic conditions induces fibroblast cell death and DNA fragmentation, which could be partially mediated by peroxynitrite synthesis.

Imiquimod applied topically: a novel immune response modifier and new class of drug.

Imiquimod (S-26308, R-837) (1-(2-methylpropyl)-1H-imidazo[4,5-c]quinolin-4 amine), an immune response modifier, demonstrates potent antiviral and antitumor activity in animal models (see structure in Fig. 1). The drug exhibits no direct antiviral or antiproliferative activity when tested in a number of cell culture systems. Imiquimod's activity was discovered while screening for anti-herpes virus activity. One of the first analogs in the series, S-25059 was tested in the early 1980's and due to slight toxicity, caused slightly reduced herpes cytopathology in Vero cell cultures. Follow-up testing in herpes infected guinea pigs showed complete protection toward lesion development. Activity of these drugs results primarily from interferon alpha (IFN-alpha) induction and other cytokine induction. At least part of the cytokine induction is mediated through NF-kappaB activation. These cytokines stimulate several other aspects of the innate immune response. In addition, imiquimod stimulates acquired immunity, in particular the cellular arm which is important for control of viral infections and various tumors. This effect is mediated by drug induced IFN-alpha and Interleukin-12 (IL-12) and IFN-gamma induced by these cytokines. Imiquimod is expected to be effective where exogenous IFN-alpha has shown utility and where enhancement of cell-mediated immunity is needed. The following is a brief review of the preclinical pharmacology of imiquimod and the clinical results of genital wart trials. The mechanism of action of topically applied imiquimod will likely lead to benefits in several other chronic virus infections and tumors of the skin. Two other reviews on imiquimod that focus mainly on the clinical results have been published (Beutner & Geisse, 1997; Slade, Owens, Tomai & Miller, 1998).

S-nitrosoglutathione enhances neutrophil DNA fragmentation and cell death.

Enhancing the clearance of neutrophils by enhancing apoptotic cell death and macrophage recognition may be beneficial in acute lung injury. Exogenous nitric oxide gas depresses neutrophil oxidative functions and accelerates cell death (A. H. Daher, J. D. Fortenberry, M. L. Owens, and L. A. Brown. Am. J. Respir. Cell Mol. Biol. 16: 407-412, 1997). We hypothesized that S-nitrosoglutathione (GSNO), a physiologically relevant nitric oxide donor, could also enhance neutrophil DNA fragmentation. Neutrophils were incubated for 2-24 h in the absence and presence of GSNO (dose range 0.1-5 mM) and evaluated for cell death by a fluorescent viability/cytotoxicity assay. Neutrophil DNA fragmentation was assessed by cell death detection ELISA and by terminal deoxynucleotidyltransferase-mediated fluorescence-labeled dUTP nick end labeling assay. Neutrophil oxidative function was also determined. Incubation with GSNO increased cell death at 2, 4, and 24 h. GSNO incubation for 24 h significantly increased DNA fragmentation in a dose-dependent fashion at 0.5 (median 126% of control value; P = 0.002) and 5 mM (185% of control value; P = 0.002) by terminal deoxynucleotidyltransferase-mediated fluorescence-labeled dUTP nick end labeling and at 0.5 mM by ELISA (164% of control value; P = 0.03). The apoptosis-to-total cell death ratio increased with increasing GSNO concentration (P < 0.05). Effects were mitigated by coincubation with superoxide dismutase. Five millimolar GSNO decreased overall superoxide generation and O2 consumption but not when adjusted for dead neutrophils. GSNO significantly enhances cell death and neutrophil DNA fragmentation in a dose-dependent fashion.

Imiquimod, a patient-applied immune-response modifier for treatment of external genital warts.

Genital human papillomavirus infection is one of the most common sexually transmitted diseases. Imiquimod is a new agent, an immune-response modifier, that has been demonstrated to have potent in vivo antiviral and antitumor effects in animal models. The present prospective, multicenter, double-blind, randomized, vehicle-controlled trial evaluated the efficacy and safety of daily patient-applied imiquimod for up to 16 weeks for the treatment of external genital warts. Wart recurrence was investigated during a 12-week treatment-free follow-up period. In the intent-to-treat analysis, baseline warts cleared from 49 of 94 (52%) patients treated with 5% imiquimod cream, 13 of 90 (14%) patients treated with 1% imiquimod cream, and 3 of 95 (4%) vehicle-treated patients; the differences between the groups treated with vehicle and imiquimod were significant (P < 0.0001). For subjects who completed the follow-up period, recurrence rates after a complete response were 19% (9 of 48 patients) in the 5% imiquimod cream group, 17% (2 of 12) in the 1% imiquimod cream group, and 0% (0 of 3) in the vehicle-treated group. There were no systemic reactions, although local skin reactions (generally of mild or moderate severity) were common, particularly in the 5% imiquimod cream group. Local reactions caused two patients to discontinue treatment. The most frequently reported local skin reactions were erythema, excoriation or flaking, and erosion. Patient-applied 5% imiquimod cream is effective for the treatment of external genital warts and has a favorable safety profile.

Exogenous nitric oxide enhances neutrophil cell death and DNA fragmentation.

Inhaled nitric oxide (NO) is an important new therapeutic agent used to treat pulmonary arterial hypertension in a variety of disease states. However, the effects of NO on cells in the lung are uncertain. Previously, we have shown that NO gas depresses neutrophil oxidative cell function and increases neutrophil cell death. The purpose of this in vitro study was to determine the mechanism of neutrophil death. We hypothesized that NO hastened cell death by inducing apoptosis. To mimic the clinical environment of patients with respiratory failure, we also studied the effects of hyperoxia on neutrophil cell viability and apoptosis. Isolated human neutrophils were exposed to 80% O2 (O2), NO at 20 ppm in room air (NO/RA), 20 ppm NO blended with 80% O2 (NO/O2), or RA alone (control) for 2 to 24 h. Experiments were repeated with NO concentrations of 5 and 50 ppm and with 20 ppm in the presence of superoxide dismutase (SOD). Neutrophils were also incubated in the absence or presence of neutrophil stimulant fMLP (10 nM). Neutrophil cell viability was measured by fluorescence viability/cytotoxicity assay. Neutrophil apoptosis was assessed by cell death detection ELISA for histone-associated DNA fragments, TdT transferase-mediated fluorescence-labeled dUTP nick end labeling (TUNEL) assay, and DNA fragmentation gel electrophoresis. NO/O2-exposed neutrophils showed decreased viability at 2 h (31.7 +/- 3.7%, mean % viability +/- SD) compared with control (94.7 +/- 4.7%), O2 (75.6 +/- 9.3%), and NO/RA (62.8 +/- 14.9%; P < 0.05 by ANOVA; n = 9). Although control neutrophils demonstrated marked apoptosis at 24 h, there was no significant apoptosis at 2, 4, or 6 h (P < 0.001 by Kruskal-Wallis, n = 20) as assessed by ELISA and TUNEL assays. When compared with RA controls at 2 h, neutrophils exposed to NO/O2 showed significantly more apoptosis (292% of control, range: 106 to 2,488%, P < 0.001 by ANOVA and Kruskal-Wallis) but not with exposure to NO/RA or O2 alone. These findings were confirmed by TUNEL assay (n = 4, P < 0.05). NO/ RA and NO/O2-exposed neutrophils demonstrated both evidence of necrosis and enhanced DNA fragmentation at 2 h by gel electrophoresis (n = 2). Fifty parts per million NO produced similar findings, but exposure to 5 ppm NO did not induce significant DNA fragmentation. Coincubation with SOD inhibited NO/ O2-associated apoptosis, suggesting peroxynitrite contributed to cell death. Stimulation with fMLP did not alter apoptosis induced in neutrophils exposed to NO/RA or NO/O2. We conclude that exogenous NO gas, at clinically relevant concentrations under hyperoxic conditions, induces cell death in neutrophils in part by enhancing DNA fragmentation.

Treatment of genital warts with an immune-response modifier (imiquimod).

BACKGROUND: Genital warts are a common sexually transmitted disease caused by human papillomavirus. Imiquimod is a novel immune-response modifier capable of inducing a variety of cytokines, including interferon alfa, tumor necrosis factor-alpha, as well as interleukins 1, 6, and 8. In animal models imiquimod has demonstrated antiviral, antitumor, and adjuvant activity. In vitro, imiquimod has no antiviral or antitumor activity. OBJECTIVE: Our purpose was to determine the safety and efficacy of topical imiquimod for the treatment of external genital warts. METHODS: This prospective double-blind, placebo-controlled, parallel design clinical trial was performed in three outpatient centers, a public health clinic, a university-based clinic, and a private practice. One hundred eight patients with external genital warts (predominantly white men) were entered into the trial. Fifty-one patients were randomly selected to receive 5% imiquimod cream; 57 patients were randomly chosen to receive placebo cream. Study medication was applied three times weekly for up to 8 weeks. Patients whose warts cleared completely were observed for up to 10 weeks to determine recurrence rates. RESULTS: In the intent-to-treat analysis, the warts of 37% (19 of 51) of the imiquimod-treated patients and 0% (0 of 57) of the placebo group cleared completely (p < 0.001). In addition, many patients experienced a partial response. A reduction in baseline wart area of 80% or more was observed in 62% of imiquimod-treated patients (28 of 45) and 4% of the placebo group (2 of 50) (p < 0.001); a 50% reduction or more in wart area was noted in 76% of imiquimod-treated patients (34 of 45) and 8% of placebo recipients (4 of 50) (p < 0.001). Of imiquimod-treated patients whose warts cleared completely and who finished the 10-week follow-up period, 19% (3 of 16) experienced recurrences of warts. Imiquimod-treated patients experienced a significantly greater number of local inflammatory reactions than the placebo group. Symptoms and signs associated with the local inflammatory reactions included itching (54.2%), erythema (33.3%), burning (31.3%), irritation (16.7%), tenderness (12.5%), ulceration (10.4%), erosion (10.4%), and pain (8.3%). There were no differences in systemic reactions or laboratory abnormalities between treatment groups. CONCLUSION: Topical 5% imiquimod cream appears to have a significant therapeutic effect in the treatment of external genital warts.

Self-administered topical 5% imiquimod cream for external anogenital warts. HPV Study Group. Human PapillomaVirus.

OBJECTIVE: To compare the safety and effectiveness of 5% and 1% imiquimod cream with vehicle cream in the treatment of external anogenital warts. DESIGN: Randomized, double-blind, placebo-controlled comparison that evaluated patients for total clearance of their warts. Patients who experienced total clearance were evaluated for recurrence in a 12-week follow-up. SETTING: Eleven ambulatory offices, including both private physician offices and referral medical centers. PATIENTS: Three hundred eleven healthy men and women aged 18 years or older with 2 to 50 external anogenital warts were recruited from the practices of investigators, referring physicians, and advertisements. Eighty-two additional patients were screened but did not qualify. Four patients discontinued use of the medication because of adverse effects. INTERVENTIONS: Five percent imiquimod (Aldara) cream, 1% imiquimod cream, or vehicle cream was applied to all external warts overnight 3 times each week for 16 weeks, or until all treated warts disappeared, whichever occurred first. MAIN OUTCOME MEASUREMENTS: The number of patients experiencing the elimination of all baseline warts and the recurrence rate of these warts. In addition, the reduction in baseline wart area the duration of therapy required to eliminate warts, and the frequency and severity of adverse reactions were principal measurements. RESULTS: In the intent-to-treat analysis, 54 (50%) of 109 patients who received 5% imiquimod cream, 21 (21%) of 102 of those who received 1% imiquimod cream, and 11 (11%) of 100 patients treated with vehicle cream experienced eradication of all treated baseline warts. The difference between the effectiveness of 5% imiquimod cream and the vehicle cream was statistically significant (P < .001). Of those patients whose warts cleared during therapy, 13% of patients who received 5% imiquimod experienced a recurrence of at least 1 wart. Recurrences occurred in none of the patients who used 1% imiquimod cream and in 10% of patients who used the vehicle cream. Local erythema was the most common adverse reaction, but the majority of patients in each group experienced no or only mild local inflammatory reactions. There were no differences in incidences of flulike symptoms among treatment groups. CONCLUSIONS: Five percent imiquimod cream is an effective and safe self-administered therapy for external anogenital warts when applied 3 times a week overnight for up to 16 weeks. The recurrence rate is low.

Imiquimod 5% cream (Aldara).

Imiquimod is a novel synthetic molecule with potent immune-modifying activities. Formulated in a 5% vanishing cream as Aldara, this self-applied therapy has shown good efficacy and safety in the treatment of external genital and perianal warts caused by human papillomavirus (HPV) infection (Condyloma acuminata). The molecule does not demonstrate direct antiviral activity, but through induction of cytokines results in immune-based resolution of wart tissue and reduction of viral burden. Phase III trials of imiquimod have demonstrated that patients who experience complete clearance of either new or recalcitrant warts tend to remain clear, possibly related to Th1 immune recognition and memory. Self-application, good tolerability and a unique mechanism of action combine to make imiquimod a reasonable first-line therapy for genital warts. The effects of imiquimod on immune function suggest several potential uses. Preclinical studies of infection with herpes simplex virus (HSV), cutaneous leishmaniasis, Rift Valley Fever virus and vesiculostomatitis virus have shown reduced viral persistence, reduced recurrence (HSV) and diminished pathology (Leishmania donovani). In a murine tumour model using the FCB bladder cancer cell line, imiquimod behaves as a potent adjuvant leading to immune-based tumour cell eradication and immunity against subsequent FCB cell challenge. The ability of imiquimod to induce significant production of interferon alpha (IFN-alpha) by monocytes/macrophages suggests that diseases responsive to recombinant interferon therapy, such as basal cell carcinoma, may be reasonable clinical targets. The induction of tumour necrosis factor alpha (TNF-alpha), interferon gamma (IFN-gamma) and interleukin-12 (IL-12) leads to inhibition of IL-5, with animal models demonstrating immune deviation away from Th2 immune responses. The observation that several patients with hepatitis C infection and eosinophilia showed normalisation of elevated eosinophil counts in association with oral imiquimod therapy encourages further exploration of the immune modifying properties of this novel molecule. This review is focused on the use of imiquimod for the treatment of external genital and perianal warts.

Effects of exogenous nitric oxide on neutrophil oxidative function and viability.

Previous studies have suggested that nitric oxide (NO) can modulate neutrophil function. Exposure to inhaled NO for pulmonary vasodilation could thus potentially affect neutrophil involvement in lung inflammation and infection. We evaluated the effect of exogenous NO gas exposure at clinically relevant concentrations in vitro on the oxidative function of human neutrophils. Isolated neutrophils were exposed for 2 h to either room air (RA), 80% oxygen (O2), or NO at 20 or 5 ppm blended with room air (NO20/RA, NO5/RA) or blended with 80% oxygen (NO20/O2) (NO5/O2). Neutrophils were then evaluated for superoxide anion generation with the cytochrome c reduction assay, for oxygen consumption with the Clark oxygen electrode technique, and for myeloperoxidase (MPO) release by enzyme-linked immunosorbent assay (ELISA). Neutrophil viability was determined by both trypan blue dye exclusion and fluorescence viability/cytotoxicity assay. Neutrophils exposed to NO at 20 ppm demonstrated a significant decrease in superoxide anion generation in both NO20/RA (97 +/- 46 nmol/10(6) neutrophils) and NO20/O2 (102 +/- 54 nmol/10(6) neutrophils) groups as compared with RA (190 +/- 41 nmol/10(6) neutrophils) (mean +/- SEM, P < 0.005 by analysis of variance [ANOVA] and the Student-Newman-Keuls test). No significant difference was seen at 5 ppm NO exposure. Neutrophil oxygen consumption was decreased with NO20/O2 (6.5 +/- 1.2 nmol O2/ml/min/10(7) neutrophils) as compared with RA (13.7 +/- 3.9 nmol O2/ml/min/10(6) neutrophils) or O2 alone (11.6 +/- 3.1 nmol O2/ml/min/10(7) neutrophils) (P < 0.002). MPO levels were significantly decreased with NO20/O2 (2.3 +/- 0.4 microg/ml) as compared with RA (4.0 +/- 0.4 microg/ml, P < 0.005), and also with NO5/O2. Cell viability as reflected by trypan blue dye exclusion was decreased with O2 (70 +/- 2.3%), NO20/RA (61 +/- 4%), and NO20/O2 (58 +/- 2.5%) exposure as compared with RA control (84.4 +/- 0.9%) (P < 0.0001). Decreased neutrophil viability was confirmed by live/dead assay for O2 (80.8 +/- 2.8%), NO20/RA (62.8 +/- 6.1%), and NO20/O2 (31.7 +/- 5.6%) groups as compared with RA control (95.8 +/- 1.4%, P < 0.0001). Adjusting neutrophil superoxide anion generation, oxygen consumption, and MPO values for cell viability abolished differences between exposure groups. We conclude that exogenous NO exposure at clinically relevant concentrations decreases neutrophil oxidative function, primarily as a result of reduced cell viability. Further studies are necessary to determine if these effects serve an in vivo immunoregulatory or immunosuppressive role in neutrophil response to lung injury and infection.

Inotropes inhibit endothelial cell surface adhesion molecules induced by interleukin-1beta.

OBJECTIVES: Leukocyte-endothelial cell interactions play a critical role in sepsis-induced multiple organ system failure and acute respiratory distress syndrome. Increased cyclic adenosine 3',5'-monophosphate (cAMP) has been previously reported to inhibit expression of the cytokine-stimulated endothelial cell adhesion molecules, E-selectin, and vascular cell adhesion molecule-1 (VCAM-1). We hypothesized that clinically relevant concentrations of inotropes, such as amrinone and dopamine, which increase cAMP, could inhibit cytokine-stimulated upregulation of endothelial adhesion proteins. DESIGN: Prospective, controlled in vitro study. SETTING: Leukocyte biology laboratory. SUBJECTS: Human umbilical vein endothelial cells isolated from neonatal umbilical cord specimens and whole blood obtained from normal human adult volunteers were used in this study. INTERVENTIONS: Endothelial cell monolayers were pretreated with increasing concentrations of amrinone or dopamine, or left untreated as controls, followed by exposure to recombinant human interleukin (IL)-1beta for 6 hrs. Monolayers were then incubated with monoclonal antibodies to E-selectin, VCAM-1, and intercellular adhesion molecule-1 (ICAM-1), fluorescence labeled, and assessed for mean fluorescence intensity by flow cytometry as a measure of surface adhesion molecule concentrations. Whole blood neutrophils were pretreated with or without inotropes, then stimulated with n-formyl methyl leucine phenylalanine. Stimulated neutrophils were incubated with antibodies against the neutrophil adherence protein CD11b and assessed by flow cytometry. MEASUREMENTS AND MAIN RESULTS: IL-1beta markedly increased E-selectin (p = .01), VCAM-1 (p < .01), and ICAM-1 (p < .001) concentrations (n = 6). Pretreatment with amrinone significantly decreased endothelial E-selectin surface values at all concentrations (p < .001 by analysis of variance, n = 5), including therapeutic concentration ranges. Amrinone also inhibited upregulation of ICAM-1 (p < .001) at therapeutic concentrations, and VCAM-1 (p < .001) at higher concentrations. Dopamine inhibited only E-selectin at relevant concentrations. Neutrophil pretreatment with inotropes did not prevent CD11b upregulation. CONCLUSIONS: Pretreatment with amrinone, and to a lesser degree, with dopamine, at clinically relevant concentrations inhibits in vitro IL-1alpha-induced increases in human umbilical vein endothelial cell adhesion molecule concentrations. Future studies are necessary to investigate the mechanisms of these effects and to determine in vivo efficacy of inotropes as anti-inflammatory agents.

Convenient oxidation of phenothiazine salts to their sulfoxides with aqueous nitrous acid.

A simple method is reported for the preparation of gram quantities of phenothiazine sulfoxides by aqueous nitrous acid oxidation of phenothiazines at room temperature. The chiral levomepromazine gave rise to diastereoisomeric products analogous to those reported for thioridazine sulfoxidation.

Inhibition by colchicine of phospholipid secretion induced by lung distension.

The effect of colchicine, a microtubule disruptor, on phospholipid secretion stimulated by distension of fetal rabbit lungs was investigated. After colchicine injection and breathing for 45 min, pups were killed and their lungs were lavaged with colchicine. Controls were injected and lavaged with saline. All lungs were given static air inflation and a final lavage, and the returns were analyzed for phospholipid DNA, and lactate dehydrogenase. The first lavage after breathing yielded 33% less phospholipid with colchicine, 3.83 compared with 5.72 mg/g dry lung wt (P less than 0.05). The postinflation phospholipid yield was also significantly reduced with colchicine from 1.04 to 0.70 mg/g dry lung wt (P less than 0.05). The postinflation DNA was significantly reduced with colchicine, from 1.26 to 0.44 micrograms (P less than 0.01), suggesting reduced alveolar macrophages. Colchicine did not change the recovery by lavage of exogenous radioactive phospholipid. As reflected by ATP and lactate levels, tissue metabolism was well maintained. The results are interpreted to mean that colchicine reduced simultaneously lavage-associated phospholipid secretion, inflation-produced phospholipid secretion, and macrophage migration.

Patency of autogenous saphenous vein versus polytetrafluoroethylene grafts in femoropopliteal bypass for advanced ischemia of the extremity.

Eighty-six femoropopliteal bypass operations were performed for ischemic ulceration, gangrene or rest pain in 77 patients whose mean preoperative ABI was 0.35. In this homogeneous patient sample, we compared prospectively a trial of saphenous vein versus PTFE grafts. During the follow-up period amputations were required in 30 per cent of the patients with a vein graft and in 31 per cent of patients with a PTFE graft. However, the presence of gangrene significantly decreased the interval to first occlusion (p less than 0.001). Over-all, autogenous saphenous vein grafts had longer patency than PTFE grafts in both the femoropopliteal and distal bypass positions. This advantage prevailed when 45 of the patients were randomized, although not at statistically significant levels. In patients without gangrene who underwent limb salvage, bypassing the diseased femoropopliteal segment with either of the graft materials increased graft patency and limb salvage compared with patients who had ischemic tissue necrosis.