In the conventionally used and thoroughly investigated emulsification method, stability of peptides and proteins is still a challenge. Emerging methods like solvent displacement, layer-by-layer polymer deposition, electrospraying and supercritical fluid technologies have the potential to improve stability of the protein and peptide. Nonetheless, these methods are still under development and they need critical evaluation to improve production efficiency before proceeding to in vivo efficacy studies. Improvement should be achieved by strengthening cooperation between academic research groups, pharmaceutical companies and regulatory authorities.

Incorporation of therapeutic proteins in a matrix of sugar glass is known to enhance protein stability, yet protection is often lost when exposed to high relative humidity (RH). We hypothesized that especially in these conditions the use of binary glasses of a polysaccharide and disaccharide might yield advantages for protein stability. Therefore, different amounts of the polysaccharide pullulan were introduced in freeze-dried trehalose glasses. In these homogeneous blends, the presence of pullulan above 50 weight % prevented crystallization of trehalose when exposed to high RH. Storage stability testing up to 4 weeks of the model protein β-galactosidase incorporated in pullulan/trehalose blends showed superior behavior of pure trehalose at 30°C/0% RH, while pullulan/trehalose blends yielded the best stability at 30°C/56% RH. In conclusion, binary glasses of pullulan and trehalose may provide excellent stability of proteins under storage conditions that may occur in practice, namely high temperature and high RH.

Injectable sustained release drug delivery systems are an attractive alternative for the intravenous delivery of therapeutic proteins. In particular, for chronic diseases such as fibrosis, this approach could improve therapy by reducing the administration frequency while avoiding large variations in plasma levels. In fibrotic tissues the platelet-derived growth factor receptor beta (PDGFβR) is highly upregulated, which provides a target for site-specific delivery of drugs. Our aim was to develop an injectable sustained release formulation for the subcutaneous delivery of the PDGFβR-targeted drug carrier protein pPB-HSA, which is composed of multiple PDGFβR-recognizing moieties (pPB) attached to human serum albumin (HSA). We used blends of biodegradable multi-block copolymers with different swelling degree to optimize the release rate using the model protein HSA from microspheres produced via a water-in-oil-in-water double emulsion evaporation process. The optimized formulation containing pPB-HSA, showed complete release in vitro within 14days. After subcutaneous administration to mice suffering from renal fibrosis pPB-HSA was released from the microspheres and distributed into plasma for at least 7days after administration. Furthermore, we demonstrated an enhanced accumulation of pPB-HSA in the fibrotic kidney. Altogether, we show that subcutaneously administered polymeric microspheres present a suitable sustained release drug delivery system for the controlled systemic delivery for proteins such as pPB-HSA.

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In this time of crisis due to the global COVID-19 pandemic, most people are staying at home to slow down the spread of the virus and the resulting pressure on their healthcare systems. This is either because of a governmentordered lockdown or self-imposed quarantine. The extent of the measures differ country-to-country and state-tostate. Where companies are allowed to stay operational or where bioanalytical laboratories are regarded part of the essential healthcare infrastructure, bioanalytical studies can still continue. Most laboratories have reduced the presence of office staff in their facilities to the absolute minimum. This includes management, project managers, study directors and supporting staff. In order to ensure continuation of the bioanalytical work, especially those which directly impact the safety of volunteers and patients in clinical studies and those which are done as part of the fight against the COVID-19 pandemic, the laboratory analysts and essential facility staff are allowed to come into the laboratory.In this editorial, we would like to give some attention to the measures taken to minimize the chance to spread the COVID-19 virus and the impact this has on the analysts working in our laboratory and the study managers.The following roles of the study manager apply: study director (SD) or principal investigator (PI) in studies with a GLP claim or the project manager (PM) in a study where samples from a clinical trial are analyzed good clinical laboratory practice (GCLP) as single point of control. General measuresNext to general preventive measures such as disinfection of the hands upon arrival in the building, we have done everything possible to ensure the recommended social distancing of at least 1.5 m in our laboratory in Assen, The Netherlands. As samples are always considered potentially hazardous and are handled as such, no additional preventive measures have been implemented for handling samples from volunteers that are not suspected to be infected with COVID-19. However, samples from volunteers suspected to be infected with COVID-19 are analyzed in our BSL-2 biohazard laboratory. Impact on the laboratory analystsDuring the critical steps of the sample preparation process at the bench in a laboratory, it can become crowded at times, so work shifts have been initiated by the analysts to decrease the number of colleagues working at the bench at the same time. The number of work places at each bench has been limited and plexiglass plates are placed between the work spaces for protection. Contact between the departments is minimized by the use of separate entrances and staircases. Now that most office staff are working from home, the analysts are spread out over the building. This includes not just the normal administration rooms of the analysts, but also in meeting rooms and offices that are currently not in use, to perform data processing. This allows us to keep a safe distance. Awkward situations may arise in the corridors, which are 1.5 m wide. Colleagues stand on the look out until th...

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