RESUMO
Sucrose and trehalose pharmaceutical excipients are employed to stabilize protein therapeutics in a dried state. The mechanism of therapeutic protein stabilization is dependent on the sugars being present in an amorphous solid-state. Colyophilization of sugars with high glass transition polymers, polyvinylpyrrolidone (PVP), and poly(vinylpyrrolidone vinyl acetate) (PVPVA), enhances amorphous sugar stability. This study investigates the stability of colyophilized sugar-polymer systems in the frozen solution state, dried state postlyophilization, and upon exposure to elevated humidity. Binary systems of sucrose or trehalose with PVP or PVPVA were lyophilized with sugar/polymer ratios ranging from 2:8 to 8:2. Frozen sugar-PVPVA solutions exhibited a higher glass transition temperature of the maximally freeze-concentrated amorphous phase (Tg') compared to sugar-PVP solutions, despite the glass transition temperature (Tg) of PVPVA being lower than PVP. Tg values of all colyophilized systems were in a similar temperature range irrespective of polymer type. Greater hydrogen bonding between sugars and PVP and the lower hygroscopicity of PVPVA influenced polymer antiplasticization effects and the plasticization effects of residual water. Plasticization due to water sorption was investigated in a dynamic vapor sorption humidity ramping experiment. Lyophilized sucrose systems exhibited increased amorphous stability compared to trehalose upon exposure to the humidity. Recrystallization of trehalose was observed and stabilized by polymer addition. Lower concentrations of PVP inhibited trehalose recrystallization compared to PVPVA. These stabilizing effects were attributed to the increased hydrogen bonding between trehalose and PVP compared to trehalose and PVPVA. Overall, the study demonstrated how differences in polymer hygroscopicity and hydrogen bonding with sugars influence the stability of colyophilized amorphous dispersions. These insights into excipient solid-state stability are relevant to the development of stabilized biopharmaceutical solid-state formulations.
Assuntos
Estabilidade de Medicamentos , Excipientes , Liofilização , Polímeros , Povidona , Temperatura de Transição , Trealose , Liofilização/métodos , Povidona/química , Trealose/química , Excipientes/química , Polímeros/química , Sacarose/química , Açúcares/química , Ligação de Hidrogênio , Armazenamento de Medicamentos , Química Farmacêutica/métodos , Varredura Diferencial de Calorimetria , Umidade , Pirrolidinas/química , Compostos de Vinila/químicaRESUMO
INTRODUCTION: Career opportunities for pharmacists beyond those commonly associated with the degree continue to emerge. A paucity of literature regarding evaluation of pharmacy graduate career paths over extended periods is apparent. Considering international pharmacy workforce capacity pressures, the primary study aim was to evaluate trends in career paths of pharmacy graduates. METHODS: This study utilised a multimethod approach to access graduate career data using publicly accessible information from LinkedIn® profiles and an online survey. The survey was distributed to all pharmacy graduates of a university (2007-2022). Data from both methods was combined, cross-checked, coded and analysed quantitatively using descriptive and inferential statistics. RESULTS: Data from 69.7% of the university's pharmacy graduates was collected. Community pharmacy was the most prevalent employment sector (47.7%), followed by industry (21.5%) and hospital (17.7%). A higher proportion of more recent graduates (≤5 years post-graduation) work in a community or hospital pharmacy role versus those who graduated greater than five years ago (χ2 = 8.44, df = 2, p < 0.05). Post-graduate education was undertaken by 41.3% of graduates. Career satisfaction was high (88.2%) but was lower (χ2 = 11.31, df = 1, p < 0.05) for those in community and hospital (82%) versus other sectors (97.5%). CONCLUSION: This study provides the first analysis of graduate career paths over an extended period, highlighting a novel approach to track pharmacist workforce. While almost two thirds of pharmacy graduates occupy community or hospital roles, a trend of leaving these settings five years post-graduation was evident. Accordingly, this work represents a springboard for additional research to inform future pharmacist workforce planning worldwide.
Assuntos
Farmácias , Farmácia , Humanos , Escolha da Profissão , Estudos Transversais , FarmacêuticosRESUMO
Dissolvable microneedle (DMN) patches are novel dosage forms for the percutaneous delivery of vaccines. DMN are routinely fabricated by dispensing liquid formulations into microneedle-shaped moulds. The liquid formulation within the mould is then dried to create dissolvable vaccine-loaded microneedles. The precision of the dispensing process is critical to the control of formulation volume loaded into each dissolvable microneedle structure. The dispensing process employed must maintain vaccine integrity. Wetting of mould surfaces by the dispensed formulation is also an important consideration for the fabrication of sharp-tipped DMN. Sharp-tipped DMN are essential for ease of percutaneous administration. In this paper, we demonstrate the ability of a piezoelectric dispensing system to dispense picolitre formulation volumes into PDMS moulds enabling the fabrication of bilayer DMN. The influence of formulation components (trehalose and polyvinyl alcohol (PVA) content) and piezoelectric actuation parameters (voltage, frequency and back pressure) on drop formation is described. The biological integrity of a seasonal influenza vaccine following dispensing was investigated and maintained voltage settings of 30 V but undermined at higher settings, 50 and 80 V. The results demonstrate the capability of piezoelectric dispensing technology to precisely fabricate bilayer DMN. They also highlight the importance of identifying formulation and actuation parameters to ensure controlled droplet formulation and vaccine stabilisation.
Assuntos
Agulhas , Sistemas de Liberação de Medicamentos , Desenho de Equipamento , Vacinas contra Influenza , Solubilidade , Tecnologia FarmacêuticaRESUMO
Dissolvable microneedle (DMN) patches for immunization have multiple benefits, including vaccine stability and ease-of-use. However, conventional DMN fabrication methods have several drawbacks. Here we describe a novel, microfluidic, drop dispensing-based dissolvable microneedle production method that overcomes these issues. Uniquely, heterogeneous arrays, consisting of microneedles of diverse composition, can be easily produced on the same patch. Robustness of the process was demonstrated by incorporating and stabilizing adenovirus and MVA vaccines. Clinically-available trivalent inactivated influenza vaccine (TIV) in DMN patches is fully stable for greater than 6months at 40°C. Immunization using low dose TIV-loaded DMN patches induced significantly higher antibody responses compared to intramuscular-based immunization in mice. TIV-loaded patches also induced a broader, heterosubtypic neutralizing antibody response. By addressing issues that will be faced in large-scale fill-finish DMN fabrication processes and demonstrating superior thermostable characteristics and immunogenicity, this study progresses the translation of this microneedle platform to eventual clinical deployment.