Monday, March 18, 2019

Manuscript “Complex Sameness” From Akina, Inc.-FDA Research Highlights Q1/Q2 Assay Methodologies


In addition to providing polymer products through the PolySciTech product line, Akina, Inc. also provides analytical and research services through the Akinalytics division (http://www.akinalytics.com/). A recent publication relates the development work performed with the Food and Drug Administration to deconstruct microparticle formulations which are constructed of more than one type of PLGA (varying lactide ratio) by applying a series of semi-solvents which dissolve higher-lactide content PLGA sequentially so each fraction can be assayed. Trelstar ® 22.5 mg dose was deconstructed by this method and each fraction was assayed. This research holds promise to develop assays which enable determination of sameness between Reference-Listed Drug (RLD) and a proposed generic. Read more: Skidmore, Sarah, Justin Hadar, John Garner, Haesun Park, Kinam Park, Yan Wang, and Xiaohui Jiang. “Complex sameness: Separation of mixed poly (lactide-co-glycolide) s based on the lactide: glycolide ratio.” Journal of Controlled Release (2019). https://doi.org/10.1016/j.jconrel.2019.03.002 [Link for 50-Days of Free access (May 5, 2019): https://authors.elsevier.com/c/1YjxgcI2~p~xz]

“Abstract: Poly (lactide-co-glycolide) (PLGA) has been used for making injectable, long-acting depot formulations for the last three decades. An in depth understanding of PLGA polymers is critical for development of depot formulations as their properties control drug release kinetics. To date, about 20 PLGA-based formulations have been approved by the U.S. Food and Drug Administration (FDA) through new drug applications, and none of them have generic counterparts on the market yet. The lack of generic PLGA products is partly due to difficulties in reverse engineering. A generic injectable PLGA product is required to establish qualitative and quantitative (Q1/Q2) sameness of PLGA to that of a reference listed drug (RLD) to obtain an approval from the FDA. Conventional characterizations of PLGA used in a formulation rely on measuring the molecular weight by gel permeation chromatography (GPC) based on polystyrene molecular weight standards, and determining the lactide:glycolide (L: G) ratio by 1H NMR and the end-group by 13C NMR. These approaches, however, may not be suitable or sufficient, if a formulation has more than one type of PLGA, especially when they have similar molecular weights, but different L:G ratios. Accordingly, there is a need to develop new assay methods for separating PLGAs possessing different L:G ratios when used in a drug product and characterizing individual PLGAs. The current work identifies a series of semi-solvents which exhibit varying degrees of PLGA solubility depending on the L:G ratio of the polymer. A good solvent dissolves PLGAs with all L:G ratios ranging from 50:50 to 100:0. A semi-solvent dissolves PLGAs with only certain L:G ratios. Almost all semi-solvents identified in this study increase their PLGA solubility as the L:G ratio increases, i.e., the lactide content increases. This lacto-selectivity, favoring higher L:G ratios, has been applied for separating individual PLGAs in a given depot formulation, leading to analysis of each type of PLGA. This semi-solvent method allows a simple, practical bench-top separation of PLGAs of varying L:G ratios. This method enables isolation and identification of individual PLGAs from a complex mixture that is critical for the quality control of PLGA formulations, as well as reverse engineering for generic products to establish the Q1/Q2 sameness. Keywords: PLGA separation L:G ratio Trelstar Q1/Q2 sameness Long-acting depot”

PLGA-Rhodamine/PLGA from PolySciTech used in development of peptide-targeted nanoparticles to macrophages for cancer therapy


Cancer is not a homogenous mass of cells, rather it is a complex mixture of microenvironment and tissue. Several factors of the microenvironment act to promote the growth of the cancer tumor. One of these is the presence of tumor-associated macrophages (immune cells) which promote the growth of cancer cells by suppressing the local immune system as well as by other mechanisms. One target for cancer therapy is to prevent the mechanisms of these support cells thereby leaving cancer more vulnerable and reducing its growth and survival. Recently, researchers at Purdue University and Soochow University (China) used PLGA (AP031) and fluorescent PLGA-Rhodamine (AV011) from PolySciTech (www.polyscitec.com) to develop peptide-bound nanoparticles with selective uptake towards these macrophages. The fluorescent PLGA enables tracking the location of the nanoparticles as a means to confirm uptake. This research holds promise for the development of powerful and selective therapies against cancer. Read more: Pang, Liang, Yihua Pei, Gozde Uzunalli, Hyesun Hyun, L. Tiffany Lyle, and Yoon Yeo. "Surface Modification of Polymeric Nanoparticles with M2pep Peptide for Drug Delivery to Tumor-Associated Macrophages." Pharmaceutical Research 36, no. 4 (2019): 65. https://link.springer.com/article/10.1007/s11095-019-2596-5

“Purpose: Tumor-associated macrophages (TAMs) with immune-suppressive M2-like phenotype constitute a significant part of tumor and support its growth, thus making an attractive therapeutic target for cancer therapy. To improve the delivery of drugs that control the survival and/or functions of TAMs, we developed nanoparticulate drug carriers with high affinity for TAMs. Methods: Poly(lactic-co-glycolic acid) nanoparticles were coated with M2pep, a peptide ligand selectively binding to M2-polarized macrophages, via a simple surface modification method based on tannic acid-iron complex. The interactions of M2pep-coated nanoparticles with macrophages of different phenotypes were tested in vitro and in vivo. PLX3397, an inhibitor of the colony stimulating factor-1 (CSF-1)/CSF-1 receptor (CSF-1R) pathway and macrophage survival, was delivered to B16F10 tumors via M2pep-modified PLGA nanoparticles. Results: In bone marrow-derived macrophages polarized to M2 phenotype, M2pep-coated nanoparticles showed greater cellular uptake than those without M2pep. Consistently, M2pep-coated nanoparticles showed relatively high localization of CD206+ macrophages in B16F10 tumors. PLX3397 encapsulated in M2pep-coated nanoparticles attenuated tumor growth better than the free drug counterpart. Conclusion: These results support that M2pep-coating can help nanoparticles to interact with M2-like TAMs and facilitate the delivery of drugs that control the tumor-supportive functions of TAMs. KEY WORDS: Drug delivery M2pep PLGA nanoparticles PLX3397 tumor-associated macrophages”

-Biotech, Pharma, Cancer, Research (BPCR) is a free, 1-day scientific networking conference hosted by Akina, Inc. on Aug 28, 2019. See more and register to attend at www.bpcrconference.com

Friday, March 15, 2019

Thermogelling PLGA-PEG-PLGA from PolySciTech used in research of healing/scar-formation of cardiovascular tissue

The formation of scar tissue, or fibrosis, is a common response to injury and is part of the healing process of most tissues. Superficial scarring is benign however when it occurs in critical areas (such as cardiovascular tissue post balloon angioplasty) it can be lethal. Recently, researchers at The Ohio State University and University of Wisconsin used thermogelling PLGA-PEG-PLGA (AK012) from PolySciTech (www.polyscitech.com) to deliver centrinone-B (a PLK4 inhibitor) as part of modeling the effect that blocking PLK4 had on healing and scar formation. This research holds promise to aid in developing therapeutics to improve cardiovascular healing as part of treatment of atherosclerosis and hypertension. Read more: Jing Li, Go Urabe, Mengxue Zhang, Yitao Huang, Bowen Wang, Lynn Marcho, Hongtao Shen, K. Craig Kent, Lian-Wang Guo “A non-canonical role of polo-like kinase-4 in adventitial fibroblast cell type transition” bioRxiv (2019) 570267; doi: https://doi.org/10.1101/570267

“Abstract: Fibroblast-to-myofibroblast transition (FMT) is central to fibrosis. A divergent member of the polo-like kinase family, PLK4 is known for its canonical role in centriole duplication. Whether this mitotic factor regulates cell type transitions was underexplored. Here we investigated PLK4’s activation and expression and regulations thereof in platelet-derived growth factor (PDGF)- induced FMT of rat aortic adventitial fibroblasts. PLK4 inhibition (with centrinone-B or siRNA) diminished not only PDGF AA-induced proliferation/migration, but also smooth muscle a-actin and its transcription factor serum response factor’s activity. While PDGFR inhibition abrogated AA-stimulated PLK4 activation (phosphorylation) and mRNA/protein expression, inhibition of p38 downstream of PDGFR had a similar effect. Further, the transcription of PLK4 (and PDGFRa) was blocked by pan-inhibition of the bromo/extraterminal-domains chromatin-bookmark readers (BRD2, BRD3, BRD4), an effect herein determined via siRNAs as mainly mediated by BRD4. In vivo, periadventitial administration of centrinone-B reduced collagen content and thickness of the adventitia in a rat model of carotid artery injury. Thus, we identified a non-canonical role for PLK4 in FMT and its regulation by a BRD4/PDGFRa-dominated pathway. This study implicates a potential PLK4-targeted antifibrotic intervention. Keywords: PLK4, PDGF receptor-a, BRD4, fibroblast-to-myofibroblast transition, fibrosis”

- Biotech, Pharma, Cancer, Research (BPCR) is a free, 1-day scientific networking conference happening in Purdue Research Park Aug 28, 2019. See more and register to attend at www.bpcrconference.com

Wednesday, March 13, 2019

PLGA from PolySciTech used in development of new, large-scale nanoparticle manufacturing technique for drug-delivery applications

Nanoparticles are generated by carefully controlling the precipitation of polymers from a dissolved state to a solid state under reproducible conditions. Conventional methods to accomplish this, such as emulsion and dialysis, do not provide for highly uniform formation conditions. As such, these create a broad dispersity of nanoparticle sizes. Recent advances in microfluidics have enabled the generation of nanoparticles of uniform size however scalability remains a challenge. Recently, researchers at San Jose State University used PLGA (PolyVivo AP030) from PolySciTech (www.polyscitech.com) to develop a novel nanoparticle manufacturing technique based on a 3D-printed Multi-inlet vortex mixers with a specific herringbone design. This research holds promise to enable larger-scale manufacturing of nanoparticles. Read more: Bokare, Anuja, Ashley Takami, Jung Han Kim, Alexis Dong, Alan Chen, Ronald Valerio, Steven Gunn, and Folarin Erogbogbo. "Herringbone-Patterned 3D-Printed Devices as Alternatives to Microfluidics for Reproducible Production of Lipid Polymer Hybrid Nanoparticles." ACS Omega 4, no. 3 (2019): 4650-4657. https://pubs.acs.org/doi/abs/10.1021/acsomega.9b00128

“Major barriers to the implementation of nanotechnology include reproducible synthesis and scalability. Batch solution phase methods do not appear to have the potential to overcome these barriers. Microfluidic methods have been investigated as a means to enable controllable and reproducible synthesis; however, the most popular constituent of microfluidics, polydimethylsiloxane, is ill-suited for mass production. Multi-inlet vortex mixers (MIVMs) have been proposed as a method for scalable nanoparticle production; however, the control and reproducibility of the nanoparticle is wanting. Here, we investigate the ability to improve the control and reproducibility of nanoparticles produced by using 3D printed MIVMs with herringbone patterns in the flow channels. We compare three methods, viz., microfluidic, MIVM, and herringbone-patterned MIVM methods, for the synthesis of lipid–polymer hybrid nanoparticles (LPHNPs). The 3D printed herringbone-patterned MIVM method resulted in the smallest LPHNPs with the most uniform size distribution and shows more reproducible results as compared to the other two methods. To elucidate the mechanism underlying these results, concentration slices and vorticity streamlines of mixing chambers have been analyzed for 3D printed herringbone-patterned MIVM devices. The results bode well for LPHNPs, a formulation widely investigated for its improved therapeutic efficacy and biocompatibility. The herringbone-patterned device also has the potential to be broadly applied to many solution phase processes that take advantage of efficient mixing. The methods discussed here have broad implications for reproducible production of nanoparticles with constituents such as siRNA, proteins, quantum dots, and inorganic materials.”

- Biotech, Pharma, Cancer, Research (BPCR) is a free, 1-day scientific networking conference happening in Purdue Research Park Aug 28, 2019. See more and register to attend at www.bpcrconference.com

- Check out PolySciTech’s new “Getting Started” guide to find initial product suggestions based on your application. You can see this here http://polyscitech.com/_start/

Tuesday, March 12, 2019

Recent Patent describes use of PolySciTech thermogels for treatment of ocular fungal infection

Fungal keratitis is a common and debilitating corneal disease in horses, with the reported incidence in North America of approximately 25% in 2013. This disease can be treated with antifungal agents such as voriconazole, however efficacy from conventional drops is low due to rapid clearance of the drug from the eye by tear formation and other processes. Recently, researchers at University of Auburn filed a patent on the use of PLGA-PEG-PLGA thermogels (Polyvivo AK012, AK024, AK019) from PolySciTech (www.polyscitech.com) for a thermogel to aid in the delivery of voriconazole as part of ocular treatment of fungal diseases. This research holds promise to prevent this potentially blinding disease. Read more: Duran, Sue H., Allison Stewart, William R. Ravis, Eva Abarca-piedrafita, Rosemary Cuming, and Mariono MORA PEREIRA. "Sustained-release voriconazole-containing thermogel and uses thereof." U.S. Patent Application 16/117,443, filed February 28, 2019. https://patents.google.com/patent/US20190060312A1/en

“Abstract: The present disclosure provides veterinary formulations comprising a therapeutically effective amount of a voriconazole and a polymer. The disclosure also provides methods, and kits for the treatment of disease, such as for treating a fungal infection in an animal utilizing the veterinary formulations. The invention relates to veterinary formulations comprising a therapeutically effective amount of a voriconazole and a polymer. First, a sustained-release veterinary formulation comprising voriconazole has great potential to improve comfort and ultimate outcome for animals suffering from keratomycosis, especially horses. Second, such a formulation can provide a treatment which would be available to all affected animals, regardless of budget, as it could be administered in the field. Third, the formulation, given via subconjunctival injection, would negate the need for frequent topical application of voriconazole to animals. This would result in minimizing stress in patients and improving compliance by decreasing the volume, frequency, and cost of medication required for treatment. Fourth, utilization of thermogel polymers (e.g., thermosensitive biodegradable hydrogels or ‘thermogels’) can advantageously be administered as a liquid, followed by conversion to a gel deposit upon reaching the appropriate temperature. As a result, the thermogel polymers can maintain a sustained release of drug at the site of administration in the animal, for example over weeks to months. The sustained release of voriconazole to an animal suffering from keratomycosis would increase the local bioavailability of the medication, decrease systemic side effects, and improve client compliance.”

- Biotech, Pharma, Cancer, Research (BPCR) is a free, 1-day scientific networking conference happening in Purdue Research Park Aug 28, 2019. See more and register to attend at www.bpcrconference.com

- Check out PolySciTech’s new “Getting Started” guide to find initial product suggestions based on your application. You can see this here http://polyscitech.com/_start/

Thursday, March 7, 2019

NEW: Product Application Starting Guide For PolySciTech Polymers


In 2007 the PolyVivo product line started with eight simple block copolymers. Since that time, the catalog has grown to encompass over six-hundred products. From its inception, PolySciTech has put our customers in the driver’s seat of innovation. The majority of PolySciTech products are results from the multitude of customer requests we’ve received for new products over the years. The benefit from this is that the catalog is comprised of polymers which are in stock, rather than a listing of theoretical items which could be made by PolySciTech under request. The drawback is that the catalog listings are not organized along any particular pattern which makes navigating it challenging.

To assist customers with finding a polymer suggestion based on their application, we have created a ‘Getting Started Guide’ with helpful information and recommendations. This can be seen on our website here https://akinainc.com/polyscitech/_start/

Tuesday, March 5, 2019

PLGA-PEG-Mal from PolySciTech used in development of Saporin-loaded Nanoparticle for HER2+ Breast Cancer Therapy



Human epidermal growth factor receptor 2 (HER2) is a specific marker which is over-expressed on certain types of breast cancer and provides an opportunity for targeting nanoparticles towards the tumor cells. Similar to ricin toxin, saporin inactivates a cells ability to synthesize proteins which ultimately leads to the cells death. Unlike ricin, however, saporin has no inherent mechanism to actually enter a cell and as such presents no toxicity unless a specific mechanism is provided for it to enter the cell. Recently, researchers at Utrecht University (Netherlands) used PLGA-PEG-Mal (AI020) from PolySciTech (www.polyscitech.com) in research to create targeted nanoparticles which bind to HER2 marker on breast cancer and used photochemical delivery to introduce saporin into these cells leading to tumor death. This research holds promise to enable the treatment of highly metastatic and treatment-resistant forms of breast cancer. Read more: Martinez Jothar, Lucia, Nataliia Beztsinna, Cornelus F. van Nostrum, Wim E. Hennink, and Sabrina Oliveira. "Selective Cytotoxicity to HER2 Positive Breast Cancer Cells by Saporin-Loaded Nanobody-Targeted Polymeric Nanoparticles in Combination With Photochemical Internalization." Molecular Pharmaceutics. https://pubs.acs.org/doi/abs/10.1021/acs.molpharmaceut.8b01318

“In cancer treatment, polymeric nanoparticles (NPs) can serve as a vehicle for the delivery of cytotoxic proteins that have intracellular targets but that lack well-defined mechanisms for cellular internalization, such as saporin. In this work we have prepared PEGylated poly(lactic acid-co-glycolic acid-co-hydroxymethyl glycolic acid) (PLGHMGA) NPs for the selective delivery of saporin in the cytosol of HER2 positive cancer cells. This selective uptake was achieved by decorating the surface of the NPs with the 11A4 nanobody that is specific for the HER2 receptor. Confocal microscopy observations showed rapid and extensive uptake of the targeted NPs (11A4-NPs) by HER2 positive cells (SkBr3), but not by HER2 negative cells (MDA-MB-231). This selective uptake was blocked upon pre-incubation of the cells with an excess of nanobody. Non-targeted NPs (Cys-NPs) were not taken up by either type of cells. Importantly, a dose-dependent cytotoxic effect was only observed on SkBr3 cells when these were treated with saporin-loaded 11A4-NPs in combination with photochemical internalization (PCI), a technique that uses a photosensitizer and local light exposure to facilitate endosomal escape of entrapped nanocarriers and biomolecules. The combined use of saporin-loaded 11A4-NPs and PCI strongly inhibited cell proliferation and decreased cell viability through induction of apoptosis. Also the cytotoxic effect could be reduced by an excess of nanobody, reinforcing the selectivity of this system. These results suggest that the combination of the targeting nanobody on the NPs with PCI are effective means to achieve selective uptake and cytotoxicity of saporin-loaded NPs.”

- Interested in using polymers for drug-delivery, but looking for advice on which one to start with? Check out PolySciTech’s new “Getting Started” guide to narrow down some initial suggestions based on your application. You can see this here http://polyscitech.com/_start/

- Biotech, Pharma, Cancer, Research (BPCR) is a free, 1-day scientific networking conference happening in Purdue Research Park Aug 28, 2019. See more and register to attend at www.bpcrconference.com