RESUMEN
Microalgae and cyanobacteria are photosynthetic microorganisms' sources of renewable biomass that can be used for bioplastic production. These microorganisms have high growth rates, and contrary to other feedstocks, such as land crops, they do not require arable land. In addition, they can be used as feedstock for bioplastic production while not competing with food sources (e.g., corn, wheat, and soy protein). In this study, we review the macromolecules from microalgae and cyanobacteria that can serve for the production of bioplastics, including starch and glycogen, polyhydroxyalkanoates (PHAs), cellulose, polylactic acid (PLA), and triacylglycerols (TAGs). In addition, we focus on the cultivation of microalgae and cyanobacteria for wastewater treatment. This approach would allow reducing nutrient supply for biomass production while treating wastewater. Thus, the combination of wastewater treatment and the production of biomass that can serve as feedstock for bioplastic production is discussed. The comprehensive information provided in this communication would expand the scope of interdisciplinary and translational research.
Asunto(s)
Cianobacterias , Microalgas , Polihidroxialcanoatos , Microalgas/metabolismo , Biomasa , Aguas Residuales , Proteínas de Soja/metabolismo , Cianobacterias/metabolismo , Celulosa , Almidón/metabolismo , Triglicéridos/metabolismo , Glucógeno/metabolismo , BiocombustiblesRESUMEN
Bionanocomposites based on natural bioactive entities have gained importance due to their abundance; renewable and environmentally benign nature; and outstanding properties with applied perspective. Additionally, their formulation with biological molecules with antimicrobial, antioxidant, and anticancer activities has been produced nowadays. The present review details the state of the art and the importance of this pyrrolic compound produced by microorganisms, with interest towards Serratia marcescens, including production strategies at a laboratory level and scale-up to bioreactors. Promising results of its biological activity have been reported to date, and the advances and applications in bionanocomposites are the most recent strategy to potentiate and to obtain new carriers for the transport and controlled release of prodigiosin. Prodigiosin, a bioactive secondary metabolite, produced by Serratia marcescens, is an effective proapoptotic agent against bacterial and fungal strains as well as cancer cell lines. Furthermore, this molecule presents antioxidant activity, which makes it ideal for treating wounds and promoting the general improvement of the immune system. Likewise, some of the characteristics of prodigiosin, such as hydrophobicity, limit its use for medical and biotechnological applications; however, this can be overcome by using it as a component of a bionanocomposite. This review focuses on the chemistry and the structure of the bionanocomposites currently developed using biorenewable resources. Moreover, the work illuminates recent developments in pyrrole-based bionanocomposites, with special insight to its application in the medical area.
Asunto(s)
Nanocompuestos , Prodigiosina , Antibacterianos/química , Reactores Biológicos , Prodigiosina/química , Prodigiosina/farmacología , Serratia marcescens/químicaRESUMEN
Free Trade Agreements (FTA) are controversial for threatening essential aspects of health, especially access to affordable medicines. The US-Peru FTA required changes in the Peruvian pharmaceutical legislation that resulted in the implementation of the National Drug Policy (NDP) of 2009. The NDP included more robust technical requirements for registration, a Peruvian Good Manufacturing Practices certificate, a longer timeline for drug registration, and an increase in registration fees. This study evaluated the impact of the FTA on the number of registrations and competition in the Peruvian pharmaceutical market. Data for the period January 2005 to April 2014 were provided by the Peruvian drug regulatory authority (Dirección General de Medicamentos, Insumos y Drogas, DIGEMID). A total of 31,114 pharmaceutical products with unique registration numbers were evaluated. Brand drug new registrations decreased from 1789 in 2005 to 455 in 2013, and the number of generic registrations decreased from 621 in 2005 to 114 in 2013. Brand re-registrations also decreased from 714 in 2005 to 58 in 2013. There were 228 brand products awaiting registration in 2009 and 1,908 in 2013. The proportion of products awaiting registration was three times greater for brand than for generic products in 2009-2013. Registration of brand and generic medicines significantly declined after the implementation of the US-Peru FTA in 2009. The decline in the number of registrations was associated with more robust technical requirements, a longer DIGEMID registration timeline, and an increase in registration fees. The stronger registration requirements are expected to increase the quality of the drugs marketed in the country, but also less competition and a reduction in domestic registrations.
RESUMEN
Antidepressants are drugs with a direct action on the brain's biochemistry through their interaction with the neurotransmitters, such as dopamine, norepinephrine, and serotonin. The increasing worldwide contamination from these drugs may be witnessed through their increasing presence in the urban water cycle. Furthermore, their occurrence has been detected in non-urban water, such as rivers and oceans. Some endemic aquatic animals, such as certain fish and mollusks, have bioaccumulated different antidepressant drugs in their tissues. This problem will increase in the years to come because the present COVID-19 pandemic has increased the general worldwide occurrence of depression and anxiety, triggering the consumption of antidepressants and, consequently, their presence in the environment. This work provides information on the occurrence of the most administrated antidepressants in urban waters, wastewater treatment plants, rivers, and oceans. Furthermore, it provides an overview of the analytical approaches currently used to detect each antidepressant presented. Finally, the ecotoxicological effect of antidepressants on several in vivo models are listed. Considering the information provided in this review, there is an urgent need to test the presence of antidepressant members of the MAOI and TCA groups. Furthermore, incorporating new degradation/immobilization technologies in WWTPs will be useful to stop the increasing occurrence of these drugs in the environment.
Asunto(s)
COVID-19 , Contaminantes Químicos del Agua , Antidepresivos , Monitoreo del Ambiente , Humanos , Pandemias , Ríos , SARS-CoV-2 , Aguas Residuales/análisis , Contaminantes Químicos del Agua/análisisRESUMEN
BACKGROUND: Starting in August 2015, there was an increase in the number of cases of neonatal microcephaly in Northeast Brazil. These findings were identified as being an epidemic of microcephaly related to Zika virus (ZIKV) infection. The present study aims to analyse the spatial distribution of microcephaly cases in Recife (2015-2016), which is in Northeast Brazil, and its association with the living conditions in this city. METHODS: This was an ecological study that used data from reported cases of microcephaly from the State Health Department of Pernambuco (August 2015 to July 2016). The basic spatial unit of analysis was the 94 districts of Recife. The case definition of microcephaly was: neonates with a head circumference of less than the cut-off point of -2 standard deviations below the mean value from the established Fenton growth curve. As an indicator of the living conditions of the 94 districts, the percentage of heads of households with an income of less than twice the minimum wage was calculated. The districts were classified into four homogeneous strata using the K-means clustering algorithm. We plotted the locations of each microcephaly case over a layer of living conditions. RESULTS: During the study period, 347 microcephaly cases were reported, of which 142 (40.9%) fulfilled the definition of a microcephaly case. Stratification of the 94 districts resulted in the identification of four strata. The highest stratum in relation to the living conditions presented the lowest prevalence rate of microcephaly, and the overall difference between this rate and the rates of the other strata was statistically significant. The results of the Kruskal-Wallis test demonstrated that there was a strong association between a higher prevalence of microcephaly and poor living conditions. After the first 6 months of the study period, there were no microcephaly cases recorded within the population living in the richest socio-economic strata. CONCLUSION: This study showed that those residing in areas with precarious living conditions had a higher prevalence of microcephaly compared with populations with better living conditions.
Asunto(s)
Epidemias , Microcefalia/epidemiología , Microcefalia/virología , Complicaciones Infecciosas del Embarazo/epidemiología , Características de la Residencia/estadística & datos numéricos , Condiciones Sociales/estadística & datos numéricos , Infección por el Virus Zika/epidemiología , Brasil/epidemiología , Femenino , Humanos , Recién Nacido , Embarazo , Prevalencia , Factores SocioeconómicosRESUMEN
BACKGROUND: A Zika virus epidemic emerged in northeast Brazil in 2015 and was followed by a striking increase in congenital microcephaly cases, triggering a declaration of an international public health emergency. This is the final report of the first case-control study evaluating the potential causes of microcephaly: congenital Zika virus infection, vaccines, and larvicides. The published preliminary report suggested a strong association between microcephaly and congenital Zika virus infection. METHODS: We did a case-control study in eight public maternity hospitals in Recife, Brazil. Cases were neonates born with microcephaly, defined as a head circumference of 2 SD below the mean. Two controls without microcephaly were matched to each case by expected date of delivery and area of residence. We tested the serum of cases and controls and the CSF of cases for detection of Zika virus genomes with quantitative RT-PCR and for detection of IgM antibodies with capture-IgM ELISA. We also tested maternal serum with plaque reduction neutralisation assays for Zika and dengue viruses. We estimated matched crude and adjusted odds ratios with exact conditional logistic regression to determine the association between microcephaly and Zika virus infection. FINDINGS: We screened neonates born between Jan 15 and Nov 30, 2016, and prospectively recruited 91 cases and 173 controls. In 32 (35%) cases, congenital Zika virus infection was confirmed by laboratory tests and no controls had confirmed Zika virus infections. 69 (83%) of 83 cases with known birthweight were small for gestational age, compared with eight (5%) of 173 controls. The overall matched odds ratio was 73·1 (95% CI 13·0-∞) for microcephaly and Zika virus infection after adjustments. Neither vaccination during pregnancy or use of the larvicide pyriproxyfen was associated with microcephaly. Results of laboratory tests for Zika virus and brain imaging results were available for 79 (87%) cases; within these cases, ten were positive for Zika virus and had cerebral abnormalities, 13 were positive for Zika infection but had no cerebral abnormalities, and 11 were negative for Zika virus but had cerebral abnormalities. INTERPRETATION: The association between microcephaly and congenital Zika virus infection was confirmed. We provide evidence of the absence of an effect of other potential factors, such as exposure to pyriproxyfen or vaccines (tetanus, diphtheria, and acellular pertussis, measles and rubella, or measles, mumps, and rubella) during pregnancy, confirming the findings of an ecological study of pyriproxyfen in Pernambuco and previous studies on the safety of Tdap vaccine administration during pregnancy. FUNDING: Brazilian Ministry of Health, Pan American Health Organization, and Enhancing Research Activity in Epidemic Situations.
Asunto(s)
Infección por el Virus Zika/complicaciones , Infección por el Virus Zika/epidemiología , Adolescente , Adulto , Brasil/epidemiología , Estudios de Casos y Controles , Femenino , Humanos , Recién Nacido , Masculino , Microcefalia , Madres , Factores de Riesgo , Adulto JovenAsunto(s)
Síndrome de Guillain-Barré/epidemiología , Microcefalia/epidemiología , Complicaciones Infecciosas del Embarazo , Infección por el Virus Zika/epidemiología , Virus Zika , Brasil/epidemiología , Epidemias , Femenino , Síndrome de Guillain-Barré/etiología , Humanos , Incidencia , Microcefalia/etiología , Embarazo , Infección por el Virus Zika/complicacionesRESUMEN
BACKGROUND: The microcephaly epidemic, which started in Brazil in 2015, was declared a Public Health Emergency of International Concern by WHO in 2016. We report the preliminary results of a case-control study investigating the association between microcephaly and Zika virus infection during pregnancy. METHODS: We did this case-control study in eight public hospitals in Recife, Brazil. Cases were neonates with microcephaly. Two controls (neonates without microcephaly), matched by expected date of delivery and area of residence, were selected for each case. Serum samples of cases and controls and cerebrospinal fluid samples of cases were tested for Zika virus-specific IgM and by quantitative RT-PCR. Laboratory-confirmed Zika virus infection during pregnancy was defined as detection of Zika virus-specific IgM or a positive RT-PCR result in neonates. Maternal serum samples were tested by plaque reduction neutralisation assay for Zika virus and dengue virus. We estimated crude odds ratios (ORs) and 95% CIs using a median unbiased estimator for binary data in an unconditional logistic regression model. We estimated ORs separately for cases with and without radiological evidence of brain abnormalities. FINDINGS: Between Jan 15, 2016, and May 2, 2016, we prospectively recruited 32 cases and 62 controls. 24 (80%) of 30 mothers of cases had Zika virus infection compared with 39 (64%) of 61 mothers of controls (p=0·12). 13 (41%) of 32 cases and none of 62 controls had laboratory-confirmed Zika virus infection; crude overall OR 55·5 (95% CI 8·6-∞); OR 113·3 (95% CI 14·5-∞) for seven cases with brain abnormalities; and OR 24·7 (95% CI 2·9-∞) for four cases without brain abnormalities. INTERPRETATION: Our data suggest that the microcephaly epidemic is a result of congenital Zika virus infection. We await further data from this ongoing study to assess other potential risk factors and to confirm the strength of association in a larger sample size. FUNDING: Brazilian Ministry of Health, Pan American Health Organization, and Enhancing Research Activity in Epidemic Situations.
Asunto(s)
Microcefalia/epidemiología , Infección por el Virus Zika/diagnóstico , Virus Zika/aislamiento & purificación , Brasil/epidemiología , Estudios de Casos y Controles , Femenino , Edad Gestacional , Humanos , Microcefalia/patología , Microcefalia/virología , Neuroimagen , Embarazo , Complicaciones Infecciosas del Embarazo/epidemiología , Complicaciones Infecciosas del Embarazo/patología , Complicaciones Infecciosas del Embarazo/virología , Estudios Prospectivos , Factores de Riesgo , Infección por el Virus Zika/congénito , Infección por el Virus Zika/epidemiología , Infección por el Virus Zika/patologíaAsunto(s)
Humanos , Masculino , Femenino , Desarrollo Sostenible , Conservación de los Recursos Naturales , Desarrollo Económico , Salud Ambiental , Brasil , AtlasRESUMEN
OBJECTIVE: To explore the presence and magnitude of--and change in--socioeconomic and health inequalities between and within Brazil, the Russian Federation, India, China and South Africa--the countries known as BRICS--between 1990 and 2010. METHODS: Comparable data on socioeconomic and health indicators, at both country and primary subnational levels, were obtained from publicly available sources. Health inequalities between and within countries were identified and summarized by using standard gap and gradient metrics. FINDINGS: Four of the BRICS countries showed increases in both income level and income inequality between 1990 and 2010. The exception was Brazil, where income inequality decreased over the same period. Between-country inequalities in level of education and access to sanitation remained mostly unchanged but the largest between-country difference in mean life expectancy increased, from 9 years in 1990 to 20 years in 2010. Throughout the study period, there was disproportionality in the burden of disease between BRICS. However, the national infant mortality rate fell substantially over the study period in all five countries. In Brazil and China, the magnitude of subnational income-related inequalities in infant mortality, both absolute and relative, also decreased substantially. CONCLUSION: Despite the economic prosperity and general improvements in health seen since 1990, profound inequalities in health persist both within and between BRICS. However, the substantial reductions observed--within Brazil and China--in the inequalities in income-related levels of infant mortality are encouraging.
Asunto(s)
Disparidades en el Estado de Salud , Mortalidad Infantil/tendencias , Brasil/epidemiología , China/epidemiología , Indicadores de Salud , Disparidades en Atención de Salud , Humanos , Renta , India/epidemiología , Lactante , Mortalidad Materna/tendencias , Análisis de Regresión , Federación de Rusia/epidemiología , Factores Socioeconómicos , Sudáfrica/epidemiología , Naciones UnidasRESUMEN
AIM: To investigate the factors associated with hepatitis C virus (HCV) infection among non-injecting cocaine users (NICUs) and to compare practices associated with HCV and HIV infection. DESIGN: An intercountry cross-sectional study. Setting Buenos Aires and Montevideo metropolitan areas. PARTICIPANTS: A total of 871 NICUs. MEASUREMENTS: NICUs were interviewed and their blood was drawn and used for HCV, HIV, HBV surface antigen (HbsAg), HB-anticore and Venereal Disease Research Laboratory (VRDL) antibody assays. Bivariate and multivariate logistic regression analyses included comparisons of HCV and HIV mono-infected participants with HCV-HIV seronegatives. FINDINGS: Prevalence rates were 8.8 [95% confidence interval (CI): 6.9-10.8) for HCV and 7.9 (95% CI: 6.1-9.7) for HIV. HCV-infected NICUs were twice as likely as HCV-HIV seronegatives to have shared straws for cocaine snorting or sniffing, even when adjusted for other variables. HCV prevalence rates ranged from 3.6% among NICUs who denied sharing straws and having had an injection drug user (IDU) or an HIV-positive sexual partner to 12.6% among participants who reported ever having shared straws or having had either an IDU- or HIV-positive sexual partner (χ(2) (trend) = 6.56, P = 0.01). CONCLUSIONS: Non-injecting cocaine users from South America are vulnerable to multiple infections and HCV infection appears to occur through the sharing of straws. HCV infection is associated with intimate relationships with IDUs or HIV-seropositive partners, supporting the hypothesis that HCV risk may be due primarily to risk-taking behaviour associated with drugs in this population.
Asunto(s)
Trastornos Relacionados con Cocaína/epidemiología , Cocaína/administración & dosificación , Hepatitis C/epidemiología , Abuso de Sustancias por Vía Intravenosa/epidemiología , Adolescente , Adulto , Argentina/epidemiología , Trastornos Relacionados con Cocaína/complicaciones , Comorbilidad , Métodos Epidemiológicos , Femenino , Infecciones por VIH/epidemiología , Hepatitis B/epidemiología , Hepatitis C/transmisión , Humanos , Masculino , Asunción de Riesgos , Conducta Sexual , Parejas Sexuales , Abuso de Sustancias por Vía Intravenosa/complicaciones , Población Urbana/estadística & datos numéricos , Uruguay/epidemiologíaRESUMEN
The aim is to estimate HBV prevalence and the associated risks among noninjecting cocaine users (NICUs). In 2002-2003, a total of 824 NICUs from Buenos Aires (Argentina) and Montevideo (Uruguay) were interviewed using a structured questionnaire. Serologic tests were carried out for Human Immunodeficiency Virus (HIV), hepatitis B (HBV), syphilis, and others. The population was divided into two serologic groups: HBV-infected and seronegative group. Univariate and binary logistic model were developed. The results seem to indicate that, among NICUs, HBV is transmitted through sexual contact. Prevention measures, including vaccine, are needed in order to control and minimize risks. The study's limitations are noted.
Asunto(s)
Trastornos Relacionados con Cocaína/epidemiología , Hepatitis B/epidemiología , Conducta Sexual/psicología , Adulto , Argentina/epidemiología , Trastornos Relacionados con Cocaína/psicología , Trastornos Relacionados con Cocaína/virología , Estudios Transversales , Femenino , Infecciones por VIH/epidemiología , Infecciones por VIH/psicología , Infecciones por VIH/virología , Hepatitis B/psicología , Hepatitis B/virología , Humanos , Entrevistas como Asunto , Masculino , Oportunidad Relativa , Selección de Paciente , Prevalencia , Factores de Riesgo , Encuestas y Cuestionarios , Uruguay/epidemiologíaRESUMEN
Nonsteroidal anti-inflammatory drugs (NSAIDs) act upon peripheral tissues and upon the central nervous system to produce analgesia. A major central target of NSAIDs is the descending pain control system. The rostral structures of the descending pain control system send impulses towards the spinal cord and regulate the transmission of pain messages. Key structures of the descending pain control system are the periaqueductal gray matter (PAG) and the rostral ventromedial region of the medulla (RVM), both of which are critical targets for endogenous opioids and opiate pharmaceuticals. NSAIDs also act upon PAG and RVM to produce analgesia and, if repeatedly administered, induce tolerance to themselves and cross-tolerance to opioids. Experimental evidence shows that this is due to an interaction of NSAIDs with endogenous opioids along the descending pain control system. Analgesia by NSAIDs along the descending pain control system also requires an activation of the CB1 endocannabinoid receptor. Several experimental approaches suggest that opioids, NSAIDs and cannabinoids in PAG and RVM cooperate to decrease GABAergic inhibition and thus enhance the descending flow of impulses that inhibit pain.
RESUMEN
Guyana's pharmaceutical sector faces major challenges that limit access to essential drugs. This study analyzes Guyana's drug policy and regulation, public financing, and drug procurement and delivery. The study also identifies main barriers to drug access and proposes alternatives to strengthen the country's public health functions. Data were collected from the country's regulatory agencies, public procurement agency, pharmacies, wholesalers, and pharmaceutical companies. The information was supplemented with interviews with a convenient sample of Guyanese health authorities and stakeholders. Data were also compiled from scientific databases, and web pages of the country's Ministries of Health, Commerce and Finance, the Bureau of Statistics, and international organizations. Major barriers to drug access include: (1) lack of national drug policy and regulation, and limited role of the regulatory authority; (2) inefficient drug selection and irrational drug use; (3) insufficient financial resources and lack of drug pricing policy; (4) inefficient planning and managing public supply system; (5) deficient epidemiological and information systems; and (6) inadequate infrastructures and human resources shortage. Improving drug access in Guyana requires the strengthening of the country's public health functions and the implementation of a national drug policy and pricing policy, streamlining the drug financing, procurement, and planning and managing drug supply; and adequate infrastructures and human resources.
Asunto(s)
Medicamentos Esenciales/provisión & distribución , Accesibilidad a los Servicios de Salud , Formulación de Políticas , Salud Pública , Bases de Datos como Asunto , Costos de los Medicamentos , Control de Medicamentos y Narcóticos , Medicamentos Esenciales/economía , Guyana , HumanosRESUMEN
The Uruguay Round Agreements Act (URAA) was enacted by the United States Congress in 1994. The URAA provided substantial modifications to the framework for U.S. patent law that came into effect January 1, 1953. Changes in patent regulation are especially important in the pharmaceutical sector because the patent system determines, in large part, the reward that an inventor can derive from discovery of a new drug. Most pharmaceutical patents are classified as utility patents. Pharmaceutical patents may include claims for the active ingredient per se, for the formulation of the active ingredient for use as a pharmaceutical, for therapeutic indications and uses, and for methods of manufacturing the drug. The U.S. has a First-to-Invent system to establishing the right of priority of an invention, but most countries have a First-to-File priority system. The First-to-Invent system allows for public disclosure of inventions prior to patent filing. In contrast, the First-to-File system encourages early filing of patent applications. In both systems, filing an application for a patent as soon as the drug is discovered allows inventors to obtain an earlier date of invention relative to potential competitors and establish the right of priority over the invention.
Asunto(s)
Aprobación de Drogas/legislación & jurisprudencia , Legislación de Medicamentos , Patentes como Asunto/legislación & jurisprudencia , Humanos , Preparaciones Farmacéuticas , Factores de Tiempo , Estados UnidosRESUMEN
Metamizol (dipyrone) and other nonsteroidal anti-inflammatory drugs (NSAIDs) induce antinociception by acting upon peripheral tissues and upon central nervous system structures, notably the periaqueductal grey matter (PAG) and the spinal cord. Inflammation-induced hyperalgesia is prevented by spinal application of NSAIDs before the inflammation, but once central sensitization is established the spinal effect of NSAIDs is uncertain. The present study examines whether the action upon the PAG contributes to the attenuation of inflammation-induced spinal hyperalgesia by NSAIDs. In deeply anaesthetized rats, responses of spinal multireceptive neurons to mechanical stimulation of the ipsilateral paw and leg were recorded. An inflammation in the paw was induced with carrageenan. Fifty minutes later, neuronal responses to innocuous and noxious stimulation had, respectively, increased to 206 and 304% for paw, and 160 and 190% for leg. When metamizol (150 microg in 0.5 microL) was microinjected into PAG before the inflammation, neuronal hyperexcitability was delayed for approximately 60 min and was much reduced by 215 min. More interestingly, microinjection of metamizol into PAG when hyperexcitability was fully developed depressed neuronal responses down to baseline for approximately 1 h. The effect of PAG metamizol was reversed by microinjection of a GABA(A) agonist into the rostral ventromedial medulla (RVM), which indicates that RVM relays the metamizol effect from PAG onto the spinal cord. These results suggest that, upon clinical administration of NSAIDs, a joint action upon PAG and spinal cord contributes to preventing the development of hyperalgesia but it is mainly the action upon PAG which contributes to reducing fully established hyperalgesia.
Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Dipirona/uso terapéutico , Hiperalgesia/prevención & control , Bulbo Raquídeo/efectos de los fármacos , Sustancia Gris Periacueductal/efectos de los fármacos , Potenciales de Acción/efectos de los fármacos , Animales , Relación Dosis-Respuesta a Droga , Extremidades/inervación , Hiperalgesia/etiología , Inflamación/complicaciones , Inflamación/etiología , Laminectomía/métodos , Masculino , Bulbo Raquídeo/fisiopatología , Microinyecciones , Neuronas Aferentes/efectos de los fármacos , Dimensión del Dolor , Sustancia Gris Periacueductal/fisiopatología , Ratas , Ratas Sprague-Dawley , Médula Espinal/patologíaRESUMEN
OBJECTIVES: This study analyses the effect of the Andean countries' June 2003 negotiation of antiretroviral drug (ARV) prices. The objectives were to assess the problems faced during the negotiation process, to evaluate the impact of the negotiation on ARV prices, and to identify factors that could make it difficult for countries to implement the results of the negotiation. METHODS: Price information of ARVs purchased by public programmes during 2004 was collected from the ministries of health. A survey of the ministries of health was conducted using a questionnaire with information related to the countries' health care and drug regulations and policies. Interviews with a convenient sample of key Andean health authorities and other stakeholders were also conducted. RESULTS: Study results show that the negotiation did achieve lower prices and higher quality and bioequivalence standards for ARVs. However, in general, the public health care programmes of the six countries analysed did not purchase ARVs from the companies that participated in the negotiation, nor did they base purchases on the prices or quality and bioequivalence criteria established in the negotiation. Prices paid by the Andean countries' public programmes in 2004 were a weighted average of 65% higher than the negotiated prices; and this difference in negotiated prices vs. actual prices represented 39.5% of the programmes' ARV expenditures in 2004, or US$18 million in ARV expenditures. CONCLUSION: The successful development and implementation of multinational price negotiations requires that participant countries coordinate pharmaceutical regulations and policies, and pool procurement processes.