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1.
Sci Transl Med ; 15(683): eade6023, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36791210

RESUMO

The emergence of the SARS-CoV-2 Omicron sublineages resulted in increased transmission rates and reduced protection from vaccines. To counteract these effects, multiple booster strategies were used in different countries, although data comparing their efficiency in improving protective immunity remain sparse, especially among vulnerable populations, including older adults. The inactivated CoronaVac vaccine was among the most widely distributed vaccine worldwide and was essential in the early control of SARS-CoV-2-related hospitalizations and deaths. However, it is not well understood whether homologous versus heterologous booster doses in those fully vaccinated with CoronaVac induce distinct humoral responses or whether these responses vary across age groups. We analyzed plasma antibody responses from CoronaVac-vaccinated younger or older individuals who received a homologous CoronaVac or heterologous BNT162b2 or ChAdOx1 booster vaccine. All three evaluated boosters resulted in increased virus-specific IgG titers 28 days after the booster dose. However, we found that both IgG titers against SARS-CoV-2 Spike or RBD and neutralization titers against Omicron sublineages were substantially reduced in participants who received homologous CoronaVac compared with the heterologous BNT162b2 or ChAdOx1 booster. This effect was specifically prominent in recipients >50 years of age. In this group, the CoronaVac booster induced low virus-specific IgG titers and failed to elevate neutralization titers against any Omicron sublineage. Our results point to the notable inefficiency of CoronaVac immunization and boosting in mounting protective antiviral humoral immunity, particularly among older adults, during the Omicron wave. These observations also point to benefits of heterologous regimens in high-risk populations fully vaccinated with CoronaVac.


Assuntos
Formação de Anticorpos , COVID-19 , Humanos , Idoso , Vacina BNT162 , SARS-CoV-2 , Imunoglobulina G , Anticorpos Antivirais
2.
Cienc. Salud (St. Domingo) ; 6(2): 103-109, 20220520. ilus
Artigo em Espanhol | LILACS | ID: biblio-1379471

RESUMO

La COVID-19 es la enfermedad causada por el nuevo coronavirus conocido como SARS-CoV-2. Para finales del 2020, la FDA de los Estados Unidos aprobó la primera vacuna para su uso de emergencia contra el COVID-19, desarrollada por Pfizer y BioNTech (BNT162b2). Este nuevo tipo de vacuna utiliza ARN mensajero modificado, el cual le da instrucciones al organismo para generar un fragmento de la proteína espiga de la superficie del virus, y que por sí sola desencadena una respuesta inmunitaria que ayuda a proteger el organismo contra una infección por COVID-19. Dentro de los eventos adversos menos comunes reportados en los estudios clínicos iniciales está la linfadenopatía (0.3 %). Objetivo: reportar el caso de paciente masculino que acude a evaluación sonográfica por preocupación de nódulo palpable en región supraclavicular. Resultados: a la evaluación sonográfica se observa cadena ganglionar reactiva compatible con una linfadenopatía. Paciente reporta vacunación de refuerzo con la vacuna Pfizer 8 días antes de la evaluación, subsecuente a dos vacunas Coronavac, corroborando de que se trata de una linfadenopatía reactiva, secundaria a una respuesta inmune robusta al refuerzo con la vacuna Pfizer. Se realiza una medición de Anti-SARS-CoV-2 TrimericS IgG cuantitativa a los 15 días del refuerzo con Pfizer, reportando valores elevados de 10,600 BAU/mL. Se orientó al paciente a regresar en una semana para seguimiento ecográfico, el cual evidenció resolución espontánea sin secuelas. Conclusiones: los hallazgos de adenopatía axilar o supraclavicular unilateral subsecuentes a la vacunación por COVID-19 deben ser informados tanto a médicos como pacientes, como un efecto secundario temporal producto de la respuesta inmunológica post vacuna. Este hallazgo benigno no requiere seguimiento adicional de imágenes y mucho menos de procedimientos invasivos como biopsias, los cuales generan mucha ansiedad al paciente, además de ser muy costosos para los mismos


COVID-19 is a disease caused by a new coronavirus identified as SARS-CoV-2. Towards the end of 2020, the FDA of the United States approved the first vaccine for emergency use against COVID-19, which was developed by Pfizer and BioNTech (BNT162b2). This new type of vaccine uses a modified RNA Messenger, which gives instructions to the host cells of the vaccinated person to produce a fragment of the spike protein of the virus, which then generates an inmune response and protects the recipient of the vaccine against COVID-19. Among the adverse events less frequently reported in the initial clinical studies of the vaccine is lymphadenopathy which was reported by 0.3% of the participants. Objective: Presentation of a case report of a male subject that came to a ultrasound evaluation due to concern of a palpable nodule in the supraclavicular región. Results: Ultrasound exam showed reactive unilateral cervical and supraclavicular lymphadenopathy. Patient reports a third dose booster with the Pfizer-BioNTech COVID-19 (BNT162b2) vaccine, 8 days prior to the evaluation, after completing a two-dose vaccination schedule with the Coronavac/Sinovac vaccine, confirming a vigorous immune response to the mRNA anti-COVID vaccines. This response was validated by elevated Anti-SARS-CoV-2 TrimericS IgG (10,600 BAU/mL). Patient was informed to return in a week for an echography follow-up which showed spontaneous resolution without leaving sequelae. Conclusions: It is of great importance to inform this benign finding of supraclavicular or axillar adenopathy subsequent to COVID vaccination to the medical community and patients, to avoid unnecessary medical interventions such as imaging or biopsies, which generate anxiety to the patient as well as additional costs


Assuntos
Humanos , Masculino , Adulto , Imunização Secundária , Linfadenopatia/induzido quimicamente , Vacina BNT162/efeitos adversos , Remissão Espontânea , Clavícula , Linfadenopatia/diagnóstico por imagem , COVID-19/prevenção & controle , Linfonodos , Pescoço
3.
J Womens Health (Larchmt) ; 31(9): 1343-1352, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35363574

RESUMO

Background: Women worldwide face risks from pregnancy, HIV, and other sexually transmitted infections (STIs). To date, highly effective contraceptive methods provide no HIV/STI protection, and HIV prevention products, excluding condoms, provide no pregnancy protection. Intravaginal rings (IVRs) delivering antiretrovirals and contraceptives are a promising multipurpose prevention technology (MPT). Methods: Embedded within a Phase I randomized, placebo-controlled trial, we examined acceptability of continuous versus interrupted use of a 90-day MPT IVR among 47 low-risk women in Norfolk, Virginia and the Dominican Republic. A baseline survey assessed menstruation attitudes, risk perceptions and trial-related motivations. Follow-up surveys (M1/M3) examined user experiences with and preferences for IVR attributes; 18 women also participated in two in-depth interviews. Results: Most women rated the IVR's flexibility and smoothness (86%) and ease of insertion/removal (76%) as very acceptable. Fewer women similarly rated the IVR size (57%) and changes in color from menstruation (52%). Most participants experienced no changes or less bleeding. Those reporting more/heavier bleeding (20% M1, 15% M3) disliked the change. Overall, women preferred a 3-month (75%) to a 1-month IVR (7.5%) or a bimonthly injectable (10%). In qualitative interviews, women were willing to continuously use an IVR for 6-12 months, providing it did not "degrade" inside the body. Reasons for trial participation and prevention preferences, menstrual attitudes, and perceived IVR benefits and doubts varied by site. Conclusions: Findings provide strong evidence of demand for an MPT IVR that protects from pregnancy and HIV/STIs, lasts longer than 1 month, minimally disrupts menstrual bleeding, and is in women's control. numberClinicalTrials.gov: #NCT03279120.


Assuntos
Dispositivos Anticoncepcionais Femininos , Infecções por HIV , Infecções Sexualmente Transmissíveis , Anticoncepcionais , República Dominicana , Feminino , Infecções por HIV/prevenção & controle , Humanos , Infecções Sexualmente Transmissíveis/prevenção & controle
4.
Contraception ; 113: 95-100, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35483431

RESUMO

OBJECTIVE: We assessed the acceptability of subcutaneous depot-medroxyprogesterone acetate 104 mg (Sayana® Press) when injected every 4 months for 12 months. STUDY DESIGN: We assessed acceptability using questionnaires within a clinical trial to evaluate contraceptive effectiveness of Sayana® Press when the reinjection interval was extended from 3 to 4 months. We enrolled 750 women aged 18 to 35 years and at risk of pregnancy at 3 centers in Brazil, Chile, and the Dominican Republic who agreed to use Sayana® Press every 4 months for 12 months. Acceptability outcomes included responses to questions about perception of bleeding patterns and side effects, likes, and dislikes about the regimen. We descriptively compared outcomes across study centers and between those who completed the study and those who discontinued early. RESULTS: Across the 3 centers, participants differed in age, marital status, years of schooling, and race. At the final visit, 90% reported being satisfied with Sayana® Press and 75% reported preferring to use this contraceptive every 4 months. The most common reasons women liked using Sayana® Press were for its duration of effectiveness, followed by amenorrhea. The most common dislike, when a reason was identified, was its effect on uterine bleeding, including amenorrhea reported by some participants. We also observed center-level differences in the proportion of women who liked amenorrhea. CONCLUSIONS: Satisfaction with Sayana® Press injected every 4 months was high across the 3 demographically diverse Latin-American centers. However, participants had varied feelings towards contraceptive-induced amenorrhea. IMPLICATIONS: We found that Sayana® Press when injected every 4 months was highly acceptable among women in 3 Latin American settings despite differences in their feelings toward contraceptive-induced amenorrhea. Our results suggest that there will be interest in using this method every 4 months if introduced into these settings.


Assuntos
Anticoncepcionais Femininos , Acetato de Medroxiprogesterona , Adolescente , Adulto , Amenorreia/induzido quimicamente , Brasil , Chile , Anticoncepcionais Femininos/efeitos adversos , República Dominicana , Feminino , Humanos , Injeções Subcutâneas , Acetato de Medroxiprogesterona/efeitos adversos , Adulto Jovem
5.
Nat Med ; 28(3): 481-485, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35051990

RESUMO

The recent emergence of the SARS-CoV-2 Omicron variant is raising concerns because of its increased transmissibility and its numerous spike mutations, which have the potential to evade neutralizing antibodies elicited by COVID-19 vaccines. Here we evaluated the effects of a heterologous BNT162b2 mRNA vaccine booster on the humoral immunity of participants who had received a two-dose regimen of CoronaVac, an inactivated vaccine used globally. We found that a heterologous CoronaVac prime vaccination of two doses followed by a BNT162b2 booster induces elevated virus-specific antibody levels and potent neutralization activity against the ancestral virus and the Delta variant, resembling the titers obtained after two doses of mRNA vaccines. Although neutralization of Omicron was undetectable in participants who had received a two-dose regimen of CoronaVac, the BNT162b2 booster resulted in a 1.4-fold increase in neutralization activity against Omicron compared with the two-dose mRNA vaccine. Despite this increase, neutralizing antibody titers were reduced by 7.1-fold and 3.6-fold for Omicron compared with the ancestral strain and the Delta variant, respectively. These findings have immediate implications for multiple countries that previously used a CoronaVac regimen and reinforce the idea that the Omicron variant is associated with immune escape from vaccines or infection-induced immunity, highlighting the global need for vaccine boosters to combat the impact of emerging variants.


Assuntos
Vacina BNT162 , COVID-19 , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Humanos , SARS-CoV-2/genética , Vacinação , Vacinas Sintéticas , Vacinas de mRNA
6.
Contraception ; 104(4): 327-336, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34157312

RESUMO

OBJECTIVES: To assess pharmacodynamic and pharmacokinetic outcomes of a novel copper (Cu) intrauterine system (IUS) releasing ulipristal acetate (UPA) in healthy women. STUDY DESIGN: In this single-blinded, randomized proof-of-concept study, ovulatory women received one of three Cu-IUSs releasing low-dose UPA (5, 20 or 40 µg/d) for 12 weeks. The study included a baseline cycle, three 4-week treatment-cycles and 2 recovery cycles. Primary outcomes included effects of the IUS on bleeding profile, ovarian function, and the occurrence of progesterone receptor modulator associated endometrial changes (PAEC). Pharmacokinetics and safety profile were secondary outcomes. We compared outcomes in treatment-cycle 3 with baseline, using generalized linear mixed models with orthogonal contrasts. RESULTS: We randomized 29 women (5 µg/d = 10, 20 µg/d = 10, 40 µg/d = 9). All had a successful IUS insertion; 27 completed the 12-week treatment period. Compared to baseline, the mean number of bleeding-only days at treatment-cycle 3 declined by 16.7% in the 5 µg/d group (3.6 vs 3.0, p = 0.66), 40.5% in the 20 µg/d group (4.2 vs 2.5, p = 0.14), and 77% in the 40 µg/d group (3.9 vs 0.9, p = 0.002). Most women reported reduction in the amount of bleeding: 4/8, 8/10, and 7/9 for the 5 µg/d, 20 µg/d, and 40 µg/d groups, respectively. During IUS use, ovulation occurred in most cycles [5 µg/d: 23/24 (96%), 20 µg/d: 26/30 (87%), 40 µg/d: 22/27 (81%)]. The frequency of PAEC at IUS removal was 1/10 (10%), 1/10 (10%) and 4/9 (44%) in the 5 µg/d, 20 µg/d, and 4 0 µg/d groups, respectively. No serious adverse events occurred. CONCLUSIONS: Reduction in bleeding, low incidence of PAEC, and no serious adverse events are reassuring findings of the novel Cu-UPA-IUS. The 20 µg/d seems the lowest dose promoting a favorable bleeding profile and limiting PAEC. IMPLICATIONS: The preliminary results of this short-term study of a novel copper intrauterine system (IUS) delivering ulipristal acetate showed reduction of bleeding, low incidence of progesterone receptor modulator associated endometrial changes, and absence of serious adverse events. By preventing copper-induced increase in bleeding, this IUS could provide a noncontraceptive benefit, especially for women with low hemoglobin.


Assuntos
Anticoncepcionais Femininos , Dispositivos Intrauterinos Medicados , Norpregnadienos , Feminino , Humanos , Levanogestrel
7.
Hum Reprod ; 30(11): 2527-38, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26409014

RESUMO

STUDY QUESTION: Is there any difference in the clinical performance of the 3-year one-rod etonogestrel (ENG)- and the 5-year two-rod levonorgestrel (LNG)-releasing contraceptive implants during 3 years of insertion, and between implant and intrauterine device (IUD) contraception, in particular complaints possibly related to hormonal contraceptives? SUMMARY ANSWER: The cumulative contraceptive effectiveness after 3 years and method continuation through 2.5 years were not significantly different between ENG and LNG implants, but both outcomes were significantly worse in the non-randomized age-matched group of IUD users than in the combined implant group. WHAT IS KNOWN ALREADY: ENG- and LNG-releasing implants are safe and highly efficacious contraceptives with pregnancy rates reported to be 0.0-0.5 per 100 women-years (W-Y). No head-to-head comparative study of the two implants has been undertaken, and little information is available on comparisons of complaints of side effects of implant and copper IUD users. STUDY DESIGN, SIZE, DURATION: This was an open parallel group RCT with 1:1 allocation ratio of the ENG and the LNG implants with non-randomized control group of women choosing TCu380A IUD to address lack of reliable data on common side effects typically attributed to the use of progestogen-only contraceptives. After device(s) placement, follow-ups were at 2 weeks, 3 and 6 months, and semi-annually thereafter for 3 years or until pregnancy, removal or expulsion of the implant/IUD occurred. PARTICIPANTS, SETTING, METHODS: The study took place in family planning clinics in Brazil, Chile, Dominican Republic, Hungary, Thailand, Turkey and Zimbabwe. Women seeking long-term contraception were enlisted after an eligibility check and informed consent, and 2982 women were enrolled: 1003, 1005 and 974 in the ENG-implant, LNG-implant and IUD groups, respectively; 995, 997 and 971, respectively, were included in the per protocol analysis reported here. MAIN RESULTS AND THE ROLE OF CHANCE: ENG and LNG implants each had the same 3-year cumulative pregnancy rate of 0.4 per 100 W-Y [95% confidence interval (CI) 0.1-1.4]. A weight of ≥70 kg at admission was unrelated to pregnancy. Method continuation rates for ENG and LNG implants at 2.5 years were 69.8 (95% CI 66.8-72.6) and 71.8 per 100 W-Y (68.8-74.5), and at 3 years 12.1 (95% CI 5.2-22.0) and 52.0 per 100 W-Y (95% CI 41.8-61.2), respectively. Bleeding disturbances, the most frequent reason for method discontinuation, were significantly more common in the ENG group [16.7 (95% CI 14.4-19.3)] than in the LNG group [12.5 (95% CI 10.5-14.9)] (P 0.019). The 3-year cumulative loss to follow-up was lower in the ENG- than in the LNG-implant group, 8.1 (95% CI 6.4-10.2) and 14.4 per 100 W-Y (95% CI 12.1-17.1), respectively. The median duration of implant removal was 50 s shorter among women with ENG than among women with LNG implant (P < 0.0001). In the observational comparison between IUD and implant users, the 3-year relative risk for pregnancy in IUD group compared with the combined implant group was 5.7 per 100 W-Y (95% CI 4.4-7.3) (P = 0.0003). The 3-year expulsion rate of the IUD was 17.8 per 100 W-Y (95% CI 14.5-21.9), while the discontinuation rate for bleeding disturbances was 8.5 (95% CI 6.7-10.9). Frequency of complaints of headache and dizziness was not significantly different between implant and IUD users (P = 0.16 and 0.77, respectively), acne and bleeding irregularities were more frequent among implant users (P < 0.0001), while heavy bleeding and lower abdominal pain occurred more often among IUD than implant users (P < 0.0001). LIMITATIONS, REASONS FOR CAUTION: Few women were ≤19 years old or nulligravida, the proportion of implant users ≥70 kg was <20% and <8% were obese. WIDER IMPLICATIONS OF THE FINDINGS: Findings of the study can inform policy makers and clinicians about choice of implant, but also about TCu380A IUD in relation to implants. STUDY FUNDING/COMPETING INTERESTS: UNDP/UNFPA/WHO/UNICEF/World Bank Special Programme of Research, Development and Research Training in Human Reproduction (HRP), Department of Reproductive Health and Research (RHR), World Health Organization (WHO). This report contains the views of an international expert group and does not necessarily represent the decisions or the stated policy of the WHO. TRIAL REGISTRATION: ISRCTN33378571 registered on 22 March 2004. The first participant was enrolled on 12 May 2003.


Assuntos
Anticoncepcionais Femininos/farmacologia , Desogestrel/farmacologia , Implantes de Medicamento/farmacologia , Dispositivos Intrauterinos de Cobre , Levanogestrel/farmacologia , Avaliação de Resultados em Cuidados de Saúde , Gravidez não Planejada , Adulto , Anticoncepcionais Femininos/administração & dosagem , Anticoncepcionais Femininos/efeitos adversos , Desogestrel/administração & dosagem , Desogestrel/efeitos adversos , Implantes de Medicamento/efeitos adversos , Feminino , Humanos , Dispositivos Intrauterinos de Cobre/efeitos adversos , Levanogestrel/administração & dosagem , Levanogestrel/efeitos adversos , Gravidez , Fatores de Tempo , Adulto Jovem
8.
Obstet Gynecol ; 123(5): 1012-1022, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24785854

RESUMO

OBJECTIVE: To estimate whether continuous combined oral contraceptive pill (OCP) use leads to higher continuation and lower pregnancy rates over 12 months than cyclic use in a developing country setting. METHODS: We enrolled healthy women aged 18 to 30 years, in Santo Domingo, Dominican Republic. We randomly assigned women to cyclic or continuous use of OCPs. Participants made quarterly clinic visits for 12 months. During follow-up, we reviewed OCP adherence and continuation, side effects, and bleeding, and we tested for pregnancy. RESULTS: We enrolled 358 women (mean age, 22.7 years) and 335 (93.6%) completed the study. In intent-to-treat analyses, 77.6% of the continuous use group and 71.7% of the cyclic group continued OCPs at 12 months (P=.21). The main reason for OCP discontinuation in both groups was running out of OCPs or forgetting. Across all visits, 26.1% of women in the continuous use group and 22.3% of women in the cyclic group ever reported missing three or more OCPs in the past month (P=.43). In multivariable analyses, regimen was not associated with discontinuation, but both previous birth and perceived ease of use of OCPs decreased risk of discontinuation, whereas desire for reduced menstruation increased risk of discontinuation. Although more women reported amenorrhea or infrequent bleeding in the continuous use group, more women in the cyclic group found their bleeding patterns acceptable. Bleeding was not associated with discontinuation in multivariable analyses. Pregnancy rates at 12 months were similar (16.2% continuous and 17.4% cyclic). CONCLUSIONS: Continuous and cyclic OCP regimens were associated with similar 12-month continuation and pregnancy rates. Few factors predicted OCP discontinuation or pregnancy. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, www.clinicaltrials.gov, NCT00570440. LEVEL OF EVIDENCE: I.


Assuntos
Anticoncepcionais Orais Combinados/administração & dosagem , Conhecimentos, Atitudes e Prática em Saúde , Adesão à Medicação , Adolescente , Adulto , Anticoncepcionais Orais Combinados/efeitos adversos , República Dominicana , Feminino , Humanos , Adesão à Medicação/psicologia , Menstruação , Paridade , Satisfação do Paciente , Gravidez , Taxa de Gravidez , Inquéritos e Questionários , Adulto Jovem
9.
Contraception ; 88(5): 611-8, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23809278

RESUMO

BACKGROUND: The days just prior to ovulation are the most crucial for emergency contraception (EC) efficacy. Ulipristal acetate (UPA) and levonorgestrel's (LNG) capacity to inhibit follicular rupture have never been compared directly at this time of the cycle. STUDY DESIGN: Raw data from three pharmacodynamics studies with similar methodology were pooled to allow direct comparison of UPA, LNG and LNG + meloxicam's ability to prevent ovulation when administered orally in the advanced follicular phase, with a leading follicle of ≥ 18 mm. RESULTS: Forty eight LNG-treated (1.5 mg) cycles, 31 LNG (1.5 mg) + meloxicam (15 mg), 34 UPA (30 mg) cycles and 50 placebo cycles were compared. Follicle rupture was delayed for at least 5 days in 14.6%, 38.7%, 58.8% and 4% of the LNG-, LNG + meloxicam-, UPA- and placebo-treated cycles, respectively. UPA was more effective than LNG and placebo in inhibiting follicular rupture (p = .0001), while LNG, when administered at this time of the cycle, was not different than placebo. The addition of meloxicam improved the efficacy of LNG in preventing follicular rupture (p = .0292 vs. LNG; p = .0001 vs. placebo; non-significant vs. UPA). UPA was effective in preventing rupture in the 5 days following treatment, even when administered at the time of the luteinizing hormone (LH) surge (UPA 79%, LNG 14% and placebo 10%). None of the treatments were effective when administered on the day of the LH peak. The median time from treatment to rupture was 6 days during the ulipristal cycles and 2 days in the placebo and LNG/LNG + meloxicam cycles (p = .0015). CONCLUSION: Although no EC treatment is 100% effective in inhibiting follicular rupture when administered in the late follicular phase, UPA is the most effective treatment, delaying ovulation for at least 5 days in 59% of the cycles. LNG is not different from placebo in inhibiting follicular rupture at this advanced phase of the cycle. No treatment was effective in postponing rupture when administered on the day of LH peak.


Assuntos
Anticoncepcionais Hormonais Pós-Coito/farmacologia , Anticoncepcionais Sintéticos Pós-Coito/farmacologia , Levanogestrel/farmacologia , Norpregnadienos/farmacologia , Folículo Ovariano/efeitos dos fármacos , Ovulação/efeitos dos fármacos , Adolescente , Adulto , Chile , Estudos Cross-Over , Inibidores de Ciclo-Oxigenase/farmacologia , República Dominicana , Método Duplo-Cego , Combinação de Medicamentos , Feminino , Humanos , Estimativa de Kaplan-Meier , Luteinização/efeitos dos fármacos , Hormônio Luteinizante/sangue , Meloxicam , Tiazinas/farmacologia , Tiazóis/farmacologia , Adulto Jovem
10.
Contraception ; 85(5): 480-8, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22176795

RESUMO

BACKGROUND: Progesterone receptor modulators (PRMs) delivered by contraceptive vaginal rings provide an opportunity for development of an estrogen-free contraceptive that does not require daily oral intake of steroids. The objective of this proof-of-concept study was to determine whether continuous delivery of 600-800 mcg of ulipristal acetate (UPA) from a contraceptive vaginal ring could achieve 80% to 90% inhibition of ovulation. STUDY DESIGN: This was a prospective, controlled, open-labeled, multicenter international trial to examine the effectiveness and safety of this prototype vaginal ring. Thirty-nine healthy women, 21-40 years old and not at risk of pregnancy, were enrolled at three clinic sites. Volunteers participated in a control cycle, a 12-week treatment period and a post-treatment cycle. Pharmacodynamic effects on follicular function and inhibition of ovulation, effects on endometrium, bleeding patterns and serum UPA levels were evaluated. RESULTS: Mean UPA levels during treatment were nearly constant, approximately 5.1 ng/mL throughout the study. Ovulation was documented in 32% of 111 "4-week treatment cycles." A correlation was observed between serum UPA and degree of inhibition of ovarian activity. There was no evidence of hyperplasia of endometrium, but PRM-associated endometrial changes were frequently observed (41%). CONCLUSION: In this study, the minimum effective contraceptive dose was not established. Further studies are required testing higher doses of UPA to attain ovulation suppression in a higher percentage of subjects.


Assuntos
Anticoncepcionais Femininos/farmacologia , Dispositivos Anticoncepcionais Femininos , Endométrio/efeitos dos fármacos , Menstruação/efeitos dos fármacos , Norpregnadienos/farmacologia , Inibição da Ovulação/efeitos dos fármacos , Receptores de Progesterona/antagonistas & inibidores , Adulto , Biomarcadores/metabolismo , Proliferação de Células/efeitos dos fármacos , Anticoncepcionais Femininos/administração & dosagem , Anticoncepcionais Femininos/efeitos adversos , Anticoncepcionais Femininos/farmacocinética , Dispositivos Anticoncepcionais Femininos/efeitos adversos , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/efeitos adversos , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/farmacologia , Endométrio/citologia , Endométrio/metabolismo , Feminino , Antagonistas de Hormônios/administração & dosagem , Antagonistas de Hormônios/efeitos adversos , Antagonistas de Hormônios/farmacocinética , Antagonistas de Hormônios/farmacologia , Humanos , Imuno-Histoquímica , Menstruação/sangue , Menstruação/metabolismo , Norpregnadienos/administração & dosagem , Norpregnadienos/efeitos adversos , Norpregnadienos/farmacocinética , Folículo Ovariano/efeitos dos fármacos , Adulto Jovem
11.
Contraception ; 82(5): 418-27, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20933115

RESUMO

Development efforts on contraceptive vaginal rings were initiated over 40 years ago based on two principles: the capacity of the vaginal epithelium to absorb steroids and the capacity of elastomers to release these hormones at a nearly constant rate. Numerous models of contraceptive vaginal rings (CVRs) have been studied, but only two have reached the market: NuvaRing, a combined ring that releases etonogestrel (ENG) and ethinylestradiol (EE), and Progering, a progesterone-releasing ring for use in lactating women. The main advantages of CVRs are their effectiveness (similar to or slightly better than the pill), ease of use without the need of remembering a daily routine, user's ability to control initiation and discontinuation, nearly constant release rate allowing for lower doses, greater bioavailability and good cycle control with the combined ring. The main disadvantages are related to the mode of delivery; CVRs may cause vaginal discharge and complaints, ring expulsion is not uncommon, the ring may be felt during coitus and vaginal insertion may be unpleasant for some women. The studies reviewed in this article provide evidence that CVRs are safe, effective and highly acceptable to women. There is no doubt that CVRs offer a new, effective contraceptive option to women, expanding their available choices of hormonal contraception.


Assuntos
Anticoncepção/métodos , Dispositivos Anticoncepcionais Femininos , Adolescente , Adulto , Animais , Anticoncepção/história , Anticoncepcionais Femininos/administração & dosagem , Anticoncepcionais Femininos/efeitos adversos , Anticoncepcionais Femininos/uso terapêutico , Dispositivos Anticoncepcionais Femininos/efeitos adversos , Dispositivos Anticoncepcionais Femininos/história , Dispositivos Anticoncepcionais Femininos/tendências , Feminino , História do Século XX , História do Século XXI , Humanos , Aceitação pelo Paciente de Cuidados de Saúde , Adulto Jovem
12.
Contraception ; 79(2): 150-4, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19135574

RESUMO

BACKGROUND: The Population Council studied a pre-coital contraceptive microbicide vaginal product containing levonorgestrel (LNG) as active component and Carraguard gel as a vehicle (Carra/LNG gel) for couples who engage in occasional unplanned intercourse. The objective of this study was to evaluate the effect of sexual intercourse after vaginal application of Carra/LNG gel on serum levels of LNG in women and to assess LNG absorption by the male partner. STUDY DESIGN: This was a randomized, cross-over, pharmacokinetic study including an abstinence arm and an arm in which couples engaged in sexual intercourse between 2 and 4 h after gel application. In each study arm, each woman received a single application of Carra/LNG gel (0.75 mg in 4 mL gel) followed by serial blood samples taken at 0, 1, 2, 4, 8, 24 and 48 h after gel application for LNG measurements. In the intercourse arm, LNG was measured in blood samples taken from the male partner before intercourse and at 4, 8 and 24 h after gel application in the female partner. RESULTS: Time concentration curves for serum LNG levels showed a mean C(max) of 7.8+/-5.5 and 8.3+/-5.7 nmol/L, a mean T(max) of 6.2+/-5.9 and 7.5+/-5.7, and comparable area under the curve for the intercourse and abstinence arm, respectively. Pharmacokinetic parameters presented large variability between subjects, but excellent reproducibility within each subject. LNG was undetectable in 10 out of 12 male partners. CONCLUSION: Sexual intercourse does not appear to interfere with vaginal absorption of LNG after application of a Carra/LNG gel. A vaginal pre-coital contraceptive gel is feasible.


Assuntos
Carragenina/farmacocinética , Coito/fisiologia , Anticoncepcionais Femininos/farmacocinética , Levanogestrel/farmacocinética , Cremes, Espumas e Géis Vaginais/farmacocinética , Absorção , Administração Intravaginal , Adulto , Carragenina/administração & dosagem , Carragenina/sangue , Anticoncepcionais Femininos/administração & dosagem , Anticoncepcionais Femininos/sangue , Estudos Cross-Over , Feminino , Humanos , Levanogestrel/administração & dosagem , Levanogestrel/sangue , Masculino , Pessoa de Meia-Idade , Cremes, Espumas e Géis Vaginais/administração & dosagem
13.
Contraception ; 78(5): 418-23, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18929740

RESUMO

BACKGROUND: The SILCS diaphragm is a new, single-size contraceptive diaphragm. The objective of this crossover pilot study was to assess the fit and acceptability of the SILCS diaphragm compared to the Ortho ALL-FLEX diaphragm to validate the product design among parous women in a low-resource setting. STUDY DESIGN: Sexually active couples not at risk of pregnancy and at low risk of sexually transmitted infection were recruited and randomly assigned to one of two groups to determine order of device use. Couples used each device four times and provided feedback on key performance indicators via product-use questionnaires, a simple coital log and a gender-specific debriefing interview. RESULTS: Twenty couples provided data on a total of 160 product uses (80 for each device). Couples indicated that both diaphragms were acceptable with respect to ease of use, comfort and satisfaction with sex. At the end of the study, 19 of 20 women and 15 of 20 men reported preferring the SILCS diaphragm over the Ortho diaphragm (p

Assuntos
Dispositivos Anticoncepcionais Femininos , Aceitação pelo Paciente de Cuidados de Saúde , Administração Intravaginal , Comportamento do Consumidor , Comportamento Contraceptivo , República Dominicana , Características da Família , Feminino , Humanos , Masculino , Projetos Piloto , Gravidez , Inquéritos e Questionários
14.
Contraception ; 76(2): 111-6, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17656180

RESUMO

OBJECTIVE: The study was conducted to evaluate the effect of Carraguard vaginal gel containing 0.75 mg of levonorgestrel (CARRA/LNG gel) administered in a single dose at different stages of follicle development over subsequent follicle rupture and hormonal levels. METHOD: Randomized, blinded, cross-over study comparing the effects of a single administration of CARRA/LNG gel or Carraguard (CARRA) gel. Twenty-four healthy women were enrolled in two centers. The gels were administered when the follicle had reached diameters of 12-14, 15-17 and > or =18 mm in eight women each. Volunteers were followed for one treatment, one washout cycle and a second treatment cycle. Follicle rupture or nonrupture was assessed by transvaginal ultrasound. Luteinizing hormone, estradiol and progesterone levels were measured daily for 5 days following treatment, and three times per week until menses. RESULTS: No follicular rupture within the 5-day period following administration was observed in 74% and 30% of the CARRA/LNG and CARRA gel treatment cycles, respectively, while ovulation was documented in 4% and 61%, respectively. The overall proportion of cycles with lack of follicular rupture or ovulatory dysfunction (follicle rupture preceded by an inadequate LH surge) was 96% for CARRA/LNG and 39% in the CARRA gel cycles. CONCLUSION: Single vaginal administration of 0.75 mg LNG in CARRA gel in the late follicular phase is effective for interfering with the ovulatory process.


Assuntos
Anticoncepcionais Femininos/administração & dosagem , Levanogestrel/administração & dosagem , Folículo Ovariano/efeitos dos fármacos , Ovulação/efeitos dos fármacos , Administração Intravaginal , Adulto , Anticoncepção Pós-Coito , Anticoncepcionais Femininos/efeitos adversos , Anticoncepcionais Femininos/sangue , Estudos Cross-Over , Feminino , Humanos , Levanogestrel/efeitos adversos , Levanogestrel/sangue , Ciclo Menstrual/efeitos dos fármacos
15.
Contraception ; 75(6): 454-60, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17519152

RESUMO

OBJECTIVE: The study was conducted to assess levonorgestrel (LNG) serum levels achieved after a single administration of two different doses of Carraguard vaginal gel containing LNG (CARRA/LNG), designed for use as microbicide and contraceptive for potential dual protection. MATERIALS AND METHODS: This was a randomized double-blind pharmacokinetic study conducted in 12 subjects enrolled at two centers. Each subject received a single vaginal administration of CARRA/LNG containing either 0.75 or 1.5 mg LNG per 4 mL of gel on Days 10-12 of the menstrual cycle. LNG serum levels were measured at 0, 1, 2, 4, 8 and 12 h after administration and for the following 7 days. LH and progesterone (for a preliminary evaluation of effect on the ovarian function) as well as SHBG were measured in the daily samples. RESULTS: Serum LNG maximum concentrations (Cmax) were 14.1+/-2.1 and 11.7+/-2.7 nmol/L and Tmax was 12.0 and 6.0 h for the low and high dose, respectively, with large intersubject variability within the first 48 h. Mean levels at 96 h were 10% of Cmax. Differences in AUC between both doses were not statistically significant. SHBG levels decreased approximately 25% by Day 4 after administration. Luteal activity was observed in 3/6 and 5/6 of the subjects in the low- and high-dose group, respectively. CONCLUSION: This study demonstrates that the CARRA/LNG gel can sustain elevated serum levels of the contraceptive steroid for up to 96 h after a single application. The serum levels attained with the 0.75-mg formulation are in the range expected to perturb the ovulatory process as observed in some subjects. The lack of correlation between the administered dose and serum concentrations of the steroid may be related to a rate-limiting absorption of LNG from the vaginal mucosa. The results reported here suggest that the CARRA/LNG formulation has good potential to become a dual-protection method, possibly preventing conception and sexually transmitted infections.


Assuntos
Anti-Infecciosos/farmacocinética , Levanogestrel/farmacocinética , Administração Intravaginal , Anti-Infecciosos/administração & dosagem , Anti-Infecciosos/sangue , Área Sob a Curva , Química Farmacêutica , Chile , Anticoncepcionais Sintéticos Pós-Coito/administração & dosagem , Anticoncepcionais Sintéticos Pós-Coito/sangue , Anticoncepcionais Sintéticos Pós-Coito/farmacocinética , República Dominicana , Método Duplo-Cego , Feminino , Humanos , Absorção Intestinal , Levanogestrel/administração & dosagem , Levanogestrel/sangue , Cremes, Espumas e Géis Vaginais
16.
Contraception ; 73(4): 364-7, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16531168

RESUMO

OBJECTIVE: The purpose of this study was to understand the transition process from providing Norplant, the six-capsule first contraceptive implant system, to providing Jadelle, the two-rod second-generation system, in a clinical setting with extensive experience providing Norplant implants. MATERIALS AND METHODS: Two hundred forty-nine women requesting contraceptive implants from the PROFAMILIA clinic (Santo Domingo, Dominican Republic) were provided with information regarding the differences and similarities between the two implant systems being studied, including the easier insertion and removal procedures and the possible shorter use life associated with Jadelle. A questionnaire evaluating their preference and the reason why they chose either system was provided. The health care providers' opinions about the two systems were also studied. RESULTS: Fifty-three percent of the women preferred Jadelle over Norplant. The main reason behind their preference for Jadelle was its reduced number of implants with easier insertion and removal and less visibility in the arm, whereas that for Norplant was greater familiarity. Providers overwhelmingly preferred Jadelle. A 1-h presentation was sufficient training for providers experienced with Norplant. None had any problem with the management of Jadelle. CONCLUSION: The inclusion of Jadelle in a clinic with extensive experience with Norplant was easy and uneventful, but both methods should be available during a transition period of several months while confidence in the new method is being acquired by the community.


Assuntos
Anticoncepcionais Femininos/administração & dosagem , Levanogestrel/administração & dosagem , Atitude do Pessoal de Saúde , República Dominicana , Implantes de Medicamento , Feminino , Humanos , Satisfação do Paciente
17.
Contraception ; 73(1): 46-52, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16371294

RESUMO

OBJECTIVE: The Nestorone/ethinylestradiol (NES/EE) vaginal ring is being developed as a regular contraceptive method by the Population Council. This ring is designed to release NES 150 microg/day and EE 15 microg/day during 1 year. Here, we report a Phase I clinical trial to determine the usefulness of this ring for emergency contraception. To that end, we tested the ability of this ring to interfere with ovulation when it is inserted during the follicular phase. METHOD: Forty-eight women protected from the risk of pregnancy by nonhormonal methods were divided into three groups, which differed by the size of the dominant follicle at the time of ring insertion: 12-14 mm (n = 16), 15-17 mm (n = 18) and >or=18 mm (n = 14) diameter. The NES/EE ring was left in the vagina for 7 consecutive days, after which it was removed. The growth of the leading follicle and plasma levels of estradiol, progesterone (P), luteinizing hormone (LH) and follicle stimulating hormone (FSH) in the ensuing 5 days after ring insertion were determined. Afterwards, steroid hormones were measured twice a week, until menses took place. All women had a control cycle before the ring cycle, and the range of maximum follicular diameter assigned to each volunteer was the same for the control and the ring cycle at the time when placebo was ingested or the ring inserted. RESULTS: During the 5-day period after ring insertion with follicles 12-17 mm, ovulation was absent in 25 of 34 cycles (p < .01 vs. control), and ovulatory dysfunction (absent, blunted or mistimed LH peak) occurred in 8 of the 9 remaining cycles (33/34 ovulatory processes altered; p < .005 vs. control). After ring insertion with follicles >or=18 mm in diameter, ovulation did not occur in 2 of 14 cycles or was dysfunctional in 7 of the 12 remaining cycles (9/14 ovulatory processes altered; p<.025 vs. control). Altogether, 87.5% of ring cycles (42/48) had either no ovulation or ovulatory dysfunction in the 5-day study period, in contrast to 39.6% (19/48 cycles) in control cycles (p < .001). Among follicles that failed to rupture within the 5-day study period, none ruptured later on in the ring-treated cycles, while 9 of 16 did so in control cycles. Sixty-two percent of ring-treated cycles were shorter than 24 days. Nausea, vaginal discharge and abdominal pain were the most frequently reported adverse events during ring use. CONCLUSION: Interference with 87.5% of ovulatory processes, without ovulation occurring later in the cycle and shortening of cycle length, suggests the NES/EE ring may be used as an emergency contraceptive method, with the potential advantage of providing continuing contraception after it has performed its emergency function.


Assuntos
Anticoncepção Pós-Coito/métodos , Etinilestradiol/administração & dosagem , Norprogesteronas/administração & dosagem , Administração Intravaginal , Adulto , Estradiol/sangue , Etinilestradiol/efeitos adversos , Etinilestradiol/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Humanos , Hormônio Luteinizante/sangue , Ciclo Menstrual , Norprogesteronas/efeitos adversos , Norprogesteronas/sangue , Folículo Ovariano/diagnóstico por imagem , Ovulação , Progesterona/sangue , Ultrassonografia , Hemorragia Uterina/epidemiologia
18.
Contraception ; 73(1): 72-7, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16371299

RESUMO

BACKGROUND: Targeted research on applicator safety has not been conducted as part of microbicide clinical trials and was considered necessary for ensuring safe and effective product use. Colposcopy, regarded as a standard method for assessing the safety of vaginal products, including microbicides, was used in this study to assess the external genitalia, vaginal epithelium and cervical epithelium after a single applicator use. OBJECTIVES: The objectives of this study were to assess and compare the effects of three vaginal applicators on symptoms and signs of irritation of the external genitalia, vagina and cervix as seen by colposcopy after applicator use. METHODS: Twenty women used three different vaginal applicators over three separate clinic visits 7-14 days apart and underwent a colposcopic examination before and after each applicator use. In total, the safety of each applicator was assessed over 20 product uses. RESULTS: No severe colposcopic finding was reported. Four minor colposcopic findings (petechiae) were considered possibly related to product use. No difference was found between applicators. CONCLUSIONS: This study provides reassuring data on the safety of the three applicator products from the perspective of causing vaginal trauma or irritation. Epithelial changes that could be more important for risk of disease transmission were not observed.


Assuntos
Anti-Infecciosos/administração & dosagem , Desenho de Equipamento/efeitos adversos , Administração Intravaginal , Adolescente , Adulto , Colo do Útero/lesões , Colposcopia , República Dominicana , Feminino , Humanos , Pessoa de Meia-Idade , Vagina/lesões
19.
Contraception ; 70(6): 451-62, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15541406

RESUMO

A study (ISRCTN 77665712) was undertaken to test the effectiveness and the acceptability of vitamin E and low-dose aspirin, alone or in combination, as treatment for prolonged vaginal bleeding induced by Norplant. A total of 486 Norplant users who were requesting treatment for bleeding lasting longer than 7 days were enrolled in five centers: Beijing, China; Jakarta, Indonesia; Santiago, Chile; Santo Domingo, Dominican Republic; and Tunis, Tunisia. They were randomized to one of four different 10-day oral treatments: 200 mg vitamin E daily, 80 mg aspirin daily, both or a placebo. Treatment packs were designed to ensure blinding of both the subjects and the clinical staff. Neither vitamin E nor low-dose aspirin nor their combination was found to have any effect on reducing the length of the bleeding episode for which treatment was taken or on the vaginal bleeding patterns these women experienced during the year of follow-up.


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Aspirina/administração & dosagem , Levanogestrel/efeitos adversos , Hemorragia Uterina/tratamento farmacológico , Vitamina E/administração & dosagem , Administração Oral , Adolescente , Adulto , Chile , China , República Dominicana , Esquema de Medicação , Feminino , Humanos , Indonésia , Satisfação do Paciente , Resultado do Tratamento , Tunísia , Hemorragia Uterina/induzido quimicamente
20.
Contraception ; 69(2): 137-44, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14759619

RESUMO

A 2-year trial of a single Nestorone (NES) rod implant was conducted at three Latin American centers, each enrolling 100 women. We studied the safety, effectiveness and acceptability of this progestin-releasing contraceptive implant. Three pregnancies occurred, the last at 18 months of use. Because no pregnancies were expected in the first 18 months, the trial was halted. At that time, 224 women had completed at least 18 months of use, and 99 women had used the implant for more than 24 months. Few participants used adjunctive contraception between the time the study was halted and the time they had their implant removed. No additional pregnancies occurred before the removal of the last implant. The 2-year cumulative pregnancy rate was 1.7 per 100 with a Pearl index of 0.6 per 100 for the 2-year period. The 1-year and 2-year continuation rates were 80.5 and 66.7 per 100, respectively. Menstrual and medical disturbances were the principal reasons for discontinuation, followed by planned pregnancy. Headache and weight gain frequently led to discontinuation. The NES implant had little important effect on most clinical chemistry and lipid parameters. Over the study course, the mean change in hemoglobin was <1%. Slight modification of the design of this single 2-year implant, restoring features previously examined in clinical trials, is likely to improve its effectiveness. A single NES implant appears to provide acceptable contraception for women.


Assuntos
Anticoncepcionais Femininos/uso terapêutico , Norprogesteronas/uso terapêutico , Adolescente , Adulto , Análise de Variância , Brasil , Distribuição de Qui-Quadrado , Anticoncepcionais Femininos/administração & dosagem , Anticoncepcionais Femininos/efeitos adversos , Implantes de Medicamento , Feminino , Seguimentos , Humanos , Distúrbios Menstruais/induzido quimicamente , Norprogesteronas/administração & dosagem , Norprogesteronas/efeitos adversos , Pacientes Desistentes do Tratamento/estatística & dados numéricos , Gravidez , Gravidez não Desejada/estatística & dados numéricos , Resultado do Tratamento
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