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BACKGROUND: Food allergies are common and are associated with substantial morbidity; the only approved treatment is oral immunotherapy for peanut allergy. METHODS: In this trial, we assessed whether omalizumab, a monoclonal anti-IgE antibody, would be effective and safe as monotherapy in patients with multiple food allergies. Persons 1 to 55 years of age who were allergic to peanuts and at least two other trial-specified foods (cashew, milk, egg, walnut, wheat, and hazelnut) were screened. Inclusion required a reaction to a food challenge of 100 mg or less of peanut protein and 300 mg or less of the two other foods. Participants were randomly assigned, in a 2:1 ratio, to receive omalizumab or placebo administered subcutaneously (with the dose based on weight and IgE levels) every 2 to 4 weeks for 16 to 20 weeks, after which the challenges were repeated. The primary end point was ingestion of peanut protein in a single dose of 600 mg or more without dose-limiting symptoms. The three key secondary end points were the consumption of cashew, of milk, and of egg in single doses of at least 1000 mg each without dose-limiting symptoms. The first 60 participants (59 of whom were children or adolescents) who completed this first stage were enrolled in a 24-week open-label extension. RESULTS: Of the 462 persons who were screened, 180 underwent randomization. The analysis population consisted of the 177 children and adolescents (1 to 17 years of age). A total of 79 of the 118 participants (67%) receiving omalizumab met the primary end-point criteria, as compared with 4 of the 59 participants (7%) receiving placebo (P<0.001). Results for the key secondary end points were consistent with those of the primary end point (cashew, 41% vs. 3%; milk, 66% vs. 10%; egg, 67% vs. 0%; P<0.001 for all comparisons). Safety end points did not differ between the groups, aside from more injection-site reactions in the omalizumab group. CONCLUSIONS: In persons as young as 1 year of age with multiple food allergies, omalizumab treatment for 16 weeks was superior to placebo in increasing the reaction threshold for peanut and other common food allergens. (Funded by the National Institute of Allergy and Infectious Diseases and others; ClinicalTrials.gov number, NCT03881696.).
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Antialérgicos , Dessensibilização Imunológica , Hipersensibilidade Alimentar , Omalizumab , Adolescente , Criança , Humanos , Lactente , Alérgenos/efeitos adversos , Arachis/efeitos adversos , Dessensibilização Imunológica/métodos , Hipersensibilidade Alimentar/diagnóstico , Hipersensibilidade Alimentar/tratamento farmacológico , Hipersensibilidade Alimentar/imunologia , Hipersensibilidade Alimentar/terapia , Omalizumab/efeitos adversos , Omalizumab/uso terapêutico , Hipersensibilidade a Amendoim/tratamento farmacológico , Hipersensibilidade a Amendoim/imunologia , Hipersensibilidade a Amendoim/terapia , Antialérgicos/administração & dosagem , Antialérgicos/uso terapêutico , Pré-Escolar , Adulto Jovem , Adulto , Pessoa de Meia-IdadeRESUMO
Omalizumab is an anti-IgE monoclonal antibody currently approved for the treatment of asthma, nasal polyps/chronic rhinosinusitis with nasal polyps, and chronic spontaneous urticaria. Omalizumab is available as an injection in a prefilled syringe (PFS) with a needle safety device (NSD). New product configurations were developed to reduce the number of injections per dose administration, improve patient convenience and treatment compliance. The objective of this randomized open-label 12-week study was to demonstrate pharmacokinetic bioequivalence between (1) new PFS with autoinjector (PFS-AI), (2) new PFS-NSD configuration, and (3) current PFS-NSD configuration. Each new configuration was considered bioequivalent to the current configuration if the confidence intervals (CIs) for the geometric mean ratios (GMR) were contained in the 0.80-1.25 range for maximum concentration (Cmax), area under the concentration-time curve until the last quantifiable measurement (AUClast), and AUC extrapolated to infinity (AUCinf). Safety was assessed throughout the study. In total, 193 healthy volunteers were randomized at 1:1:1 ratio to omalizumab 1×300 mg/2 mL via new PFS-AI (n = 66), omalizumab 1×300 mg/2 mL via new PFS-NSD (n = 64), or omalizumab 2×150 mg/1 mL via current PFS-NSD (n = 63). Comparing new PFS-AI versus current PFS-NSD, the GMRs were: Cmax, 1.085; AUClast, 1.093; AUCinf, 1.100. Comparing new PFS-NSD versus current PFS-NSD, the GMRs were: Cmax, 1.006; AUClast, 1.016; AUCinf, 1.027. The 95% CIs for all GMR parameters were contained within the 0.80-1.25 range. Safety findings were consistent with the known safety profile of omalizumab. Single-dose omalizumab administered as the new PFS-AI or new PFS-NSD was bioequivalent to the current PFS-NSD.
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Área Sob a Curva , Voluntários Saudáveis , Omalizumab , Seringas , Equivalência Terapêutica , Humanos , Omalizumab/administração & dosagem , Omalizumab/farmacocinética , Omalizumab/efeitos adversos , Adulto , Masculino , Feminino , Adulto Jovem , Pessoa de Meia-Idade , Agulhas , Injeções SubcutâneasRESUMO
Purpose: Omalizumab was first approved in China in 2017 for the treatment of moderate to severe allergic asthma for adult and adolescent patients aged ≥12 years. In accordance with the Chinese Health Authority requirement, the post-authorization safety study (PASS) was conducted to evaluate the safety and effectiveness of omalizumab in a real-world setting in patients with moderate to severe allergic asthma in China over a 24-week observation period. Patients and Methods: This is a single-arm, non-interventional, multicenter, PASS conducted in adult, adolescent, and pediatric patients (≥6 years old) with moderate to severe allergic asthma receiving omalizumab in a real-world clinical setting from 2020 to 2021 in 59 sites of mainland China. Results: In total, 1546 patients were screened and 1528 were enrolled. They were stratified according to age (6 to <12 years [n = 191]; ≥12 years [n = 1336]; unknown [n = 1]). Among the overall population, 23.6% and 4.5% of patients reported adverse events (AEs) and serious adverse events (SAEs), respectively. Among pediatric patients (6 to <12 years), 14.1% and 1.6% patients reported AEs and SAEs, respectively. AEs that led to treatment discontinuation in both age groups were <2%. No new safety signals were reported. Effectiveness results showed improvement in lung function, asthma control, and quality of life (QoL). Conclusion: The findings of the current study demonstrated that the safety profile of omalizumab was consistent with its known profile in allergic asthma, and no new safety signals were reported. Omalizumab treatment was effective in improving the lung function and QoL in patients with allergic asthma.
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Chronic spontaneous urticaria (CSU) is characterized by the spontaneous development of wheals, itching, and/or angioedema, for ≥6 weeks. In China, non-sedating H1-antihistamines (H1AH) are the recommended first-line treatment, with escalation up to 4× the standard dose in symptomatic patients to achieve control. Treatment options for Chinese patients who remain symptomatic on H1AH treatment are limited. This 20-week randomized, double blind, placebo-controlled, parallel-group study investigated the efficacy and safety of omalizumab as an add-on therapy for the treatment of patients with CSU who remained symptomatic despite H1AH treatment in China. Adult patients (N = 418) diagnosed with refractory CSU for ≥6 months were randomized (2:2:1) to receive omalizumab 300 mg (OMA300), omalizumab 150 mg (OMA150) or placebo, subcutaneously, every 4 weeks. Primary outcome was change from baseline to week 12 in weekly itch severity score (ISS7). Safety was assessed by rates of adverse events (AEs). Demographic and disease characteristics at baseline were comparable across treatment groups. At week 12, statistically significant greater decreases from baseline were observed in ISS7 with OMA300 (least square mean difference [LSM]: -4.23; 95% confidence interval [CI]: -5.70, -2.77; p < 0.001) and OMA150 (LSM: -3.79; 95% CI: -5.24, -2.33; p < 0.001) versus placebo. Incidence of treatment-emergent AEs over 20 weeks was slightly higher with OMA300 (71.3%) compared to OMA150 and placebo groups (64.7% and 63.9%, respectively). The incidences of serious AEs were balanced between groups. This study demonstrated the efficacy and safety of omalizumab in Chinese adult patients with CSU who remained symptomatic despite H1AH therapy.
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Antialérgicos , Urticária Crônica , Urticária , Adulto , Antialérgicos/efeitos adversos , Doença Crônica , Urticária Crônica/diagnóstico , Urticária Crônica/tratamento farmacológico , Antagonistas dos Receptores Histamínicos H1 , Humanos , Omalizumab/efeitos adversos , Resultado do Tratamento , Urticária/induzido quimicamente , Urticária/diagnóstico , Urticária/tratamento farmacológicoRESUMO
Background: Food allergy is common and causes substantial morbidity and even mortality. Safe and effective treatments for food allergy would therefore be highly desirable, especially for individuals with multiple food allergies. Objectives: Our aim was to describe a phase 3 study on treatment of patients with multiple food allergies with omalizumab. Methods: The study was developed as a collaboration between the Consortium for Food Allergy Research, the National Institute of Allergy and Infectious Diseases, and 2 industry sponsors (Genentech and Novartis). Results: The study is currently under way, enrolling participants from age 1 year to age 55 years who are allergic to peanut and at least 2 other foods (including milk, egg, wheat, cashew, hazelnut, and walnut). The study is designed to address 3 major questions. First, stage 1 will study the potential value of omalizumab for the treatment of patients with peanut allergy and at least 2 other common food allergens. Second, stage 2 will directly compare treatment of patients with multifood allergies using omalizumab as monotherapy versus treatment with omalizumab-facilitated multiallergen oral immunotherapy in which omalizumab is used as an adjunctive treatment. Third, stage 3 will address the longer-term outcomes following these treatment approaches, including the introduction of dietary forms of the study foods to induce or maintain desensitization. Conclusions: This phase 3 study will provide important information on the potential of omalizumab to treat patients with multiple food allergies.
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BACKGROUND: Cedar pollinosis (CP), a common form of seasonal allergic rhinitis (AR), is a substantial medical problem in Japan due to its high prevalence and severe symptoms. Omalizumab (anti-IgE therapy) has previously proven to be effective in CP/AR, but no studies for inadequately controlled severe CP/AR despite standard-of-care (SoC) have been conducted. OBJECTIVE: To determine the efficacy of omalizumab added to SoC in patients with inadequately controlled severe CP in a randomized, double-blinded, placebo-controlled, phase III study. METHODS: Adult/adolescent patients with severe CP whose symptoms were inadequately controlled despite nasal corticosteroids plus 1 or more oral medications in the previous 2 seasons were randomized to receive omalizumab (n = 162) or placebo (n = 175). All patients received concomitant antihistamines and nasal corticosteroids as SoC. The primary endpoint was the mean nasal symptom score during the severe symptom period. Secondary endpoints included mean ocular symptom score, quality of life (QoL), and safety. RESULTS: The SoC + omalizumab treatment had statistically significantly and clinically important lower nasal (least squares mean difference, -1.03, P < .001) and ocular (-0.87, P < .001) symptom scores compared with SoC + placebo, respectively. Differences in scores for individual components of nasal and ocular symptoms were also statistically and clinically significant. SoC + omalizumab also improved QoL scores as overall and in all domains. No unexpected safety signals were observed. CONCLUSIONS: In patients with severe CP, omalizumab added to SoC demonstrated consistent efficacy in improving symptoms and QoL, and was well tolerated. These results indicate that omalizumab could be a promising therapeutic option for severe CP/AR.
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Omalizumab , Rinite Alérgica Sazonal , Adolescente , Adulto , Anticorpos Monoclonais , Anticorpos Monoclonais Humanizados , Método Duplo-Cego , Humanos , Japão , Omalizumab/uso terapêutico , Qualidade de Vida , Rinite Alérgica Sazonal/tratamento farmacológico , Resultado do TratamentoRESUMO
BACKGROUND: A 2-year roadmap study was conducted to evaluate the efficacy and safety of tenofovir intensification at Week 24 in patients with chronic hepatitis B (CHB) receiving telbivudine. SCOPE: A prospective multicenter study was conducted in treatment-naive patients with hepatitis B e antigen (HBeAg)-positive CHB. All patients received telbivudine (600 mg/day) until Week 24. Thereafter, patients with detectable hepatitis B virus (HBV) DNA (≥300 copies/mL) were administered tenofovir (300 mg/day) plus telbivudine, and patients with undetectable HBV DNA continued telbivudine monotherapy until Week 104. The primary endpoint was the proportion of patients with undetectable HBV DNA (<300 copies/mL) at Weeks 52 and 104. FINDINGS: A total of 105 patients were enrolled in the trial, of which 100 were eligible for efficacy analysis. Undetectable HBV DNA levels were observed at Week 24 in 55 patients who continued on with telbivudine monotherapy. The remaining 45 patients with detectable HBV DNA received tenofovir add-on therapy. With monotherapy, 100% (55/55) and 94.5% (52/55) of patients achieved HBV DNA <300 copies/mL at Weeks 52 and 104, respectively; the corresponding values for patients with add-on therapy were 84.4% (38/45) and 93.3% (42/45). Overall, undetectable HBV DNA (<300 copies/mL) was found in 93% (93/100) and 94% (94/100) of patients at Weeks 52 and 104, respectively. HBeAg seroconversion rate was 44.4% (44/99) at Week 104 for the overall patient population. One patient in the monotherapy group and six in the intensification group demonstrated HBsAg clearance at Week 104. HBsAg seroconversion was observed in four patients at Week 104, all belonged to the tenofovir intensification group. Eight patients sustained HBsAg loss during a posttreatment follow-up period of 16 weeks. Alanine aminotransferase (ALT) normalization was constant in the telbivudine monotherapy group, whereas a progressive improvement was observed in the tenofovir intensification group. Two patients in the monotherapy and none in the intensification group experienced viral breakthrough by Week 104. There were no reports of myopathy in either group. The mean changes in estimated glomerular filtration rate (eGFR), estimated using the Modification of Diet in Renal Disease (MDRD) formula, from baseline to Week 104 were +6.145 mL/min/1.73 m(2) (p=0.0230) and +7.954 mL/min/1.73 m(2) (p=0.0154) in the telbivudine monotherapy and tenofovir intensification groups, respectively. The incidence of serious AEs was four in the telbivudine monotherapy and two in the tenofovir intensification group. The main limitation of this study was limited sample size, which made the power of the observation low, and the absence of a comparative subgroup to assess the progression of patients with detectable HBV DNA without treatment intensification. CONCLUSIONS: Data from this 2-year roadmap study confirmed that telbivudine with add-on tenofovir was effective and well tolerated in patients with CHB. Telbivudine was associated with an improvement in eGFR from baseline in both the groups.
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BACKGROUND & AIMS: There is a close relationship between chronic hepatitis B virus infection and chronic renal disease. We analyzed changes in renal function using different markers of glomerular filtration rate (GFR) in multiple studies of telbivudine treatment of patients with chronic hepatitis B virus infection. METHODS: We used serum creatinine-based equations (ie, Cockcroft-Gault, Modification of Diet in Renal Disease, and Chronic Kidney Disease Epidemiology Collaboration) to estimate GFR (eGFR) in adults with chronic hepatitis B virus infection and compensated liver disease who participated in a phase III, randomized, double-blind study comparing the efficacy and safety of telbivudine (600 mg/d) and lamivudine (100 mg/d) for 2 years (the GLOBE study) and in long-term extension studies (4-6 years), as well as in patients with decompensated cirrhosis (2 years). RESULTS: eGFRs calculated using the Cockcroft-Gault, Modification of Diet in Renal Disease, and Chronic Kidney Disease Epidemiology Collaboration equations were concordant, indicating improved renal function in telbivudine-treated patients during the 2-year GLOBE study (there was an 8.5% increase in mean eGFR, based on the Modification of Diet in Renal Disease equation). Improved renal function was maintained for 4-6 years. Increased eGFR with telbivudine treatment was also observed in patients at increased risk for renal impairment: patients with baseline eGFRs of 60-89 mL/min/1.73 m(2) (+17.2%), older than 50 years (+11.4%), and with liver fibrosis/cirrhosis (+7.2% for patients with Ishak fibrosis score at 5-6). In decompensated patients with high renal risk, eGFR was also improved on telbivudine (+2.0%). CONCLUSIONS: In global trials of patients with compensated and decompensated cirrhosis, long-term telbivudine therapy was associated with a sustained improvement of renal function-particularly among patients with increased risk of renal impairment. The mechanisms of this renal protective effect remain to be determined.
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Antivirais/uso terapêutico , Taxa de Filtração Glomerular , Hepatite B Crônica/tratamento farmacológico , Insuficiência Renal Crônica/tratamento farmacológico , Timidina/análogos & derivados , Adulto , Creatinina/sangue , Método Duplo-Cego , Feminino , Hepatite B Crônica/complicações , Humanos , Masculino , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/complicações , Telbivudina , Timidina/uso terapêutico , Resultado do TratamentoRESUMO
Combination antihypertensive therapies are recommended to attain blood pressure (BP) targets especially in high-risk patients in whom rapid and pronounced BP control is essential. This 28- to 54-week, open-label, multicenter study evaluated the safety and efficacy of a triple combination, aliskiren with amlodipine and hydrochlorothiazide (HCTZ), in patients with moderate to severe hypertension. Following a washout period of up to 4 weeks, patients received aliskiren/HCTZ 300/12.5 mg for 1 week, followed by add-on amlodipine 5 mg for 1 week. Thereafter, the doses of amlodipine and HCTZ were doubled. The first 206 of 564 patients who completed 28 weeks of study continued for an additional 26 weeks. Safety was assessed by recording all adverse events. Efficacy variables included changes in BP from baseline to endpoint and BP control rate. Of 564 patients, 493 completed the study. Peripheral edema (9.4%), headache (5.7%), nasopharyngitis (4.1%), and bronchitis (3.7%) were reported frequently. Clinically significant reductions in mean sitting systolic BP/mean sitting diastolic BP from baseline (-34.2/-20.3 mm Hg and -37.3/-21.8 mm Hg at weeks 28 and 54, respectively) were observed. Corresponding BP control rates were 69.1% and 77.1%. The aliskiren/amlodipine/HCTZ combination in patients with moderate to severe hypertension was well tolerated and provided clinically significant BP reductions and effective BP control.
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Amidas , Anlodipino , Pressão Sanguínea/efeitos dos fármacos , Fumaratos , Hipertensão/tratamento farmacológico , Adulto , Idoso , Amidas/administração & dosagem , Amidas/efeitos adversos , Anlodipino/administração & dosagem , Anlodipino/efeitos adversos , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/efeitos adversos , Disponibilidade Biológica , Monitoramento de Medicamentos/métodos , Quimioterapia Combinada/métodos , Feminino , Fumaratos/administração & dosagem , Fumaratos/efeitos adversos , Humanos , Hidroclorotiazida/administração & dosagem , Hidroclorotiazida/efeitos adversos , Hipertensão/diagnóstico , Hipertensão/fisiopatologia , Pessoa de Meia-Idade , Farmacovigilância , Índice de Gravidade de Doença , Resultado do TratamentoRESUMO
OBJECTIVE: To evaluate the pharmacokinetics of a combined oral contraceptive (OC) containing oestradiol valerate/dienogest (E2V/DNG) administered according to a four-phasic dosing regimen with an oestrogen step-down and a progestin step-up over 26 days of active treatment. METHODS: This Phase I, open-label study included healthy women aged 18-50 years. Treatment consisted of the administration of E2V 3 mg for 2 days, E2V 2 mg/DNG 2 mg for 5 days, E2V 2 mg/DNG 3 mg for 17 days, E2V 1 mg for 2 days, and placebo for 2 days. RESULTS: Pharmacokinetic data were analysed in 15 women. Stable E2 concentrations were maintained throughout the study. Minimum mean serum E2 levels were 33.6-64.7 pg/ml during E2V administration. The ratio of oestrone:E2 in serum was approximately 5:1. Minimum mean serum DNG levels were 6.8-15.1 ng/ml during DNG administration. Minimum concentrations of DNG increased only slightly during each phase of the regimen during which DNG was being administered. On day 24 the geometric mean C(max), C(ave) and t((1/2)) of DNG were 82.9 ng/ml, 33.7 ng/ml and 12.2 hours, respectively; the median t(max) was 1.5 hours. Serum sex hormone-binding globulin concentrations increased by 40% (within the normal range). Cortisol binding-globulin levels remained almost unchanged. Treatment was well tolerated. CONCLUSIONS: Treatment with an OC containing E2V and DNG was well tolerated and was associated with stable E2 concentrations over 28 days. The pharmacokinetics of DNG were consistent with previous findings. Minimum serum concentrations of DNG increased only slightly during phases of the regimen during which DNG was administered.
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Anticoncepcionais Orais/farmacocinética , Estradiol/análogos & derivados , Nandrolona/análogos & derivados , Adolescente , Adulto , Proteínas de Transporte/sangue , Anticoncepcionais Orais/efeitos adversos , Anticoncepcionais Orais/sangue , Esquema de Medicação , Combinação de Medicamentos , Estradiol/efeitos adversos , Estradiol/sangue , Estradiol/farmacocinética , Feminino , Cefaleia/induzido quimicamente , Humanos , Pessoa de Meia-Idade , Nandrolona/efeitos adversos , Nandrolona/sangue , Nandrolona/farmacocinética , Radioimunoensaio , Globulina de Ligação a Hormônio Sexual/análise , Adulto JovemRESUMO
OBJECTIVE: The aim of this study was to investigate the effectiveness of microdose transdermal 17beta-estradiol (E2) therapy in postmenopausal women with moderate to severe vulvovaginal symptoms. METHODS: This report is based on a subset of 121 women who reported most bothersome moderate or severe vulvovaginal symptoms at baseline, from a previous randomized, double-blind, placebo-controlled, multicenter study of 425 healthy, symptomatic, postmenopausal women. Recruits had experienced at least 7 moderate or severe hot flushes daily for at least 1 week or at least 50 moderate or severe hot flushes per week for at least 1 week. Effects on coprimary efficacy variables have been reported previously. Participants received low-dose transdermal E2 plus levonorgestrel (n = 43; nominal delivery 0.023 mg/d E2/0.0075 mg/d levonorgestrel), microdose E2 (n = 42; nominal delivery 0.014 mg/d), or placebo (n = 36) for 12 weeks. Secondary efficacy variables reported herein include mean change from baseline in vaginal pH and vaginal maturation index, the proportion of women with symptoms of vulvar and vaginal atrophy at baseline and week 12, and the proportion of women with moderate-to-severe symptoms of vulvar and vaginal atrophy. RESULTS: Microdose transdermal E2 treatment was associated with a consistent benefit versus placebo in women with vulvovaginal atrophy. There was a statistically significant difference between both E2 versus placebo for changes in vaginal pH and vaginal maturation index. CONCLUSIONS: Microdose transdermal E2 offers a useful addition to the therapeutic armamentarium for postmenopausal women in whom vulvovaginal symptoms are particularly troublesome.
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Estradiol/uso terapêutico , Terapia de Reposição de Estrogênios/métodos , Pós-Menopausa/efeitos dos fármacos , Vagina/efeitos dos fármacos , Vulva/efeitos dos fármacos , Administração Cutânea , Adulto , Idoso , Análise de Variância , Atrofia , Método Duplo-Cego , Feminino , Humanos , Concentração de Íons de Hidrogênio , Levanogestrel/uso terapêutico , Pessoa de Meia-Idade , Pós-Menopausa/fisiologia , Índice de Gravidade de Doença , Resultado do Tratamento , Estados Unidos , Vagina/patologia , Vulva/patologiaRESUMO
OBJECTIVE: To investigate the efficacy of micro-dose transdermal estrogen in relieving menopausal vasomotor symptoms. METHODS: A randomized, double-blind, placebo-controlled, multi-center trial. Healthy postmenopausal women with at least seven moderate or severe hot flushes per day for at least 1 week, or at least 50 per week, applied transdermal patches with a nominal delivery of 0.023 mg/d 17beta-estradiol and 0.0075 mg/d levonorgestrel (low-dose E2/levonorgestrel; n=145), 0.014 mg/d E2 (micro-dose; n=147), or placebo (n=133) for 12 weeks. The coprimary efficacy variables were the mean changes from baseline in frequency and severity of moderate and severe hot flushes at the week 4 and 12 endpoints. RESULTS: At the week 12 endpoint, mean weekly frequencies of moderate and severe hot flushes were significantly reduced compared with placebo with low-dose E2/levonorgestrel (-51.80; P<.001) and micro-dose E2 (-38.46; P<.001). Severity scores were also significantly reduced with both treatments compared with placebo. At week 12 endpoint, 41.3% of women receiving micro-dose E2 were treatment responders (75% or more reduction from baseline in hot flush frequency; P=.003 compared with 24.2% placebo). In this group, the mean reduction in moderate and severe hot flushes from baseline was approximately 50% after 2, 70% after 4, 90% after 8, and 95% after 12 weeks. There were no differences between active treatments and placebo regarding adverse events. CONCLUSION: Micro-dose E2 (0.014 mg/d) was clinically and statistically significantly more effective than placebo in reducing the number of moderate and severe hot flushes, with a 41% responder rate, supporting the concept of the lowest effective dose. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, www.clinicaltrials.gov, NCT00206622