Next-generation COVID-19 vaccines are critical due to the ongoing evolution of SARS-CoV-2 virus and rapid waning duration of the neutralizing antibody response against current vaccines. The mRNA vaccines mRNA-1273 and BNT162b2 were developed using linear transcripts encoding the prefusion-stabilized trimers (S-2P) of the wildtype spike, which have shown a reduced neutralizing activity against the variants of concern B.1.617.2 and B.1.1.529. Recently, a new version of spike trimer, termed VFLIP (five (V) prolines, Flexibly-Linked, Inter-Protomer disulfide) was developed. Based on the original amino acid sequence of the wildtype spike, VFLIP was genetically engineered by using five proline substitutions, a flexible cleavage site amino acid linker, and an interprotomer disulfide bond. It has been suggested to possess native-like glycosylation, and greater pre-fusion trimeric stability as opposed to S-2P. Here, we report that the spike protein VFLIP-X, containing six rationally substituted amino acids to reflect emerging variants (K417N, L452R, T478K, E484K, N501Y and D614G), offers a promising candidate for a next-generation SARS-CoV-2 vaccine. Mice immunized by a circular mRNA (circRNA) vaccine prototype producing VFLIP-X had detectable neutralizing antibody titers for up to 7 weeks post-boost against SARS-CoV-2 variants of concern (VOCs) and variants of interest (VOIs). In addition, a balance in TH1 and TH2 responses was achieved by immunization with VFLIP-X. The researchers's results indicate that the VFLIP-X delivered by circRNA induces humoral and cellular immune responses, as well as broad neutralizing activity against SARSCoV-2 variants. The study used the following products from SINOPEG: ionizable lipidoid SM-102 (Sinopeg), 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC, Sinopeg), cholesterol (Sinopeg), 1,2-dimyristoyl-rac-glycero-3-methoxypolyethylene glycol-2000 (DMG-PEG 2000, Sinopeg) A circular mRNA vaccine prototype producing VFLIP-X spike confers a broad neutralization of SARS-CoV-2 variants by mouse sera, Antiviral Research, Volume 204, 2022, 105370, ISSN 0166-3542, https://doi.org/10.1016/j.antiviral.2022.105370. (https://www.sciencedirect.com/science/article/pii/S0166354222001395)

L-Arginine (L-Arg) depletion has attracted great attention in cancer therapy. Although two types of arginine-depleting enzymes, arginine deiminase (ADI) and human arginase I, are undergoing clinical trials, random site of PEGylation, low efficacy of heavy metal as co-factor, and immunogenicity limit the performance of these drugs and cause difficulty in a homogeneous production. Here we screened ten catalytic metal ions and have successfully produced a site-specific mono-PEGylated human arginase I mutant by conjugating the Cys45 residue to PEG-maleimide to minimize the decrease in activity and produce a homogeneous product. The catalytic efficiency trend of metal ion–enriched human arginase I mutant (HAI) was Co2+ > Ni2+ ≫ Mn2+. The overall kcat/KM values of Co-HAI and Ni-HAI were higher than Mn-HAI by ~ 8.7- and ~ 5.2-folds, respectively. Moreover, the results of enzyme kinetics and circular dichroism spectrometry demonstrated that the 20 or 40 kDa linear and branched PEG attached on the HAI surface did not affect the enzyme activity and the protein secondary structures. In vitro studies showed that both Co-HAI-PEG20L and Ni-HAI-PEG20L inhibited the growth of eight types of cancer cell lines. The pharmacodynamic study in mice demonstrated that the i.p. administration of Co-HAI-PEG20L at 13 mg/kg and Ni-HAI-PEG20L at 15 mg/kg was able to maintain a L-Arg level below its detection limit for over 120 h after one injection. The body weights of mice could return to normal levels within 5 days after injection, showing that the doses were well-tolerated. Therefore, both the Ni-HAI-PEG20L and Co-HAI-PEG20L are promising candidates for cancer therapy. SINOPEG can supply linear PEG-maleimide: Chung S F ,  Kim C F ,  Tam S Y , et al. A bioengineered arginine-depleting enzyme as a long-lasting therapeutic agent against cancer[J]. Applied Microbiology and Biotechnology, 2020, 104(6). https://doi.org/10.1007/s00253-020-10484-4

Plant-derived cholesterol is the most important raw material component in mRNA vaccine production and gene therapy. As one of the key functional excipients of lipid nanoparticles (LNPs), cholesterol plays a role in mediating LNP endocytosis as well as stabilizing the LNP structure (cholesterol helps increase the fluidity or stiffness of cell membranes and the addition of cholesterol improves the stability of nanoparticles). Meanwhile, with the rapid development of related research, lipid-based drug delivery systems are becoming increasingly important in a wider range of therapeutic areas, including vaccines for infectious diseases, cancer immunotherapy, etc. SINOPEG supplies to the market plant-derived cholesterol products of non-animal origin without genetic risk, eliminating concerns about the risk of animal-derived cholesterol carrying animal viruses, and can be used in high-end formulation excipients: small molecule liposomal drugs, nucleic acid drugs, mRNA vaccines and non-animal-derived cell culture media for protein-based drugs.

Welcome to visit us at SINOPEG's Booth #2351 at BIO International Convention 2022, San Diego, USA from 13th to 16th June. SINOPEG is mainly engaged in drug delivery system (DDS) and new medical materials business. SINOPEG has a high-level team with strong technical reserve to research, develop and produce high-quality polyethylene glycol, polyethylene glycol derivatives, block copolymers, anti-diabetic drug side chains, lipid excipients (ingredients for mRNA delivery system), ADC and ProTAC Linker, etc. Please contact us at sales@sinopeg.com #BIO

Welcome to visit us at SINOPEG's Booth #137 at Tides USA 2022, Boston, USA from 9th to 12th May. SINOPEG has a high-level team with strong technical reserve to research, develop and produce high-quality polyethylene glycol, polyethylene glycol derivatives, block copolymers, anti-diabetic drug side chains, lipid excipients (ingredients for mRNA delivery system), ADC and ProTAC Linker, etc. Please coutact us at sales@sinopeg.com

Welcome to visit us at SINOPEG's Booth #137 at Tides USA 2022, Boston, USA from 9th to 12th May.

Welcome to visit us at SINOPEG's Booth #2351 at 2022 BIO International Convention, San Diego, CA, the USA from 13th to 16th June. SINOPEG is a dynamic science company with professional R&D, Manufacturing and Sales capability. The company is mainly engaged in drug delivery system (DDS) and new medical materials business. Founded in 2011, SINOPEG has a high-level team with strong technical reserve to research, develop and produce high-quality polyethylene glycol, polyethylene glycol derivatives, block copolymers, anti-diabetic drug side chains, lipid excipients (ingredients for mRNA delivery system), ADC and ProTAC Linker, etc. SINOPEG has a technical team led by overseas returned doctors and foreign experts, established good cooperation relations with well-known universities and research institutes in China, such as Xiamen University, Fudan University and the Institute of Chemistry of Chinese Academy of Sciences. The company has the first-class technology development strength, provides services including the reaction, purification, separation and end product analysis and others according to customer needs. SINOPEG holds 24 IP, 19 pending IP, and 6 DMFs that meet FDA requirements. The company has ISO13485 certification. The laboratory and production workshop are designed and built in accordance with the cGMP standard of FDA. We follow the requirements of ICH-Q7A to organize production at scale, to provide high quality polyethylene glycol derivatives products and services to customers globally.

As COVID-19 continuing in 2021, it is necessary to take preventive measures, to accelerate the speed of research and development of COVID-19 vaccines and drugs, to advocate the innovation of new vaccines technologies, and to build the strength to win this epidemic. VacCon 2022, focus on technical breakthrough of the novel vaccines in post COVID-19 era. It will invite 60+ government regulatory experts, scientists and leading entrepreneurs who specialize in vaccine/ neutralizing antibody/ small molecule novel coronavirus drugs. The theme is "Focusing on technical breakthrough of the novel vaccines in post COVID-19 era", which will discuss the latest clinical development, before project approval and R&D in COVID-19 vaccine and drugs, and the leading practice of innovation and process development of mRNA/recombinant protein/adenovirus vector vaccine under different technical paths. SINOPEG, as one of the few companies in China to achieve the commercial production of lipid nanoparticles delivery materials, also attracted a lot of friends to communicate with us at the booth.