Paijin Biologics Files Prospectus Highlighting TE-PEP Platform for GLP-1 and GLP-2 Peptide Drug Development

Currently, peptide drugs have become one of the hotspots in global drug research and development. According to the Cortellis database, there are 1,176 clinical trials of peptide drugs worldwide, with 71 drugs already on the market, demonstrating the high level of activity in peptide drug development. Peptide drugs have emerged as the three key drivers propelling the markets for rare diseases, oncology, and diabetes treatment, with particularly unprecedented enthusiasm for R&D in the field of diabetes therapy.

Recently, held in NanjingChina Pharmaceutical Full Industry Chain New Resources ConferenceAt the Peptide Industry Innovation and Development Conference, a special session brought together numerous industry representatives to jointly discuss the latest advancements in peptide therapeutics, from research and development to manufacturing. Among them,Dr. Wen Jun, Executive Deputy General Manager of Chongqing Paijin Biotechnology, delivered a presentation titled “Synthesis and R&D of GLP-1 and GLP-2 Therapeutics Based on the TE-PEP Technology Platform,” providing a detailed introduction to the company’s highly competitive technology platform and product pipeline.

Paijin Biotech, established in 2013, is a national high-tech enterprise specializing in the research and development of recombinant protein drugs and peptide drugs. The company possesses independently owned intellectual property rights for its innovative MAS-PEG and TE-PEP core technology platforms, with product pipelines covering multiple categories such as long-acting therapeutic enzymes, peptides, and insulin. Its wholly-owned subsidiary, Chongqing Aimeidi Biotech, focuses on the R&D, production, and sales of industrial recombinant proteases, whose products are widely used in the biosynthesis of insulin and its analogs, as well as peptide drugs such as GLP-1 and GLP-2.

Dr. Wen Jun, Executive Deputy General Manager of Paijin Biotechnology, previously worked at the Medical Research Council Laboratory of Molecular Biology (LMB) in Cambridge, UK, where he focused on solid-phase synthesis research of bioactive peptides. He served as a Senior Scientist for many years at a US Pharmacopeia-affiliated drug development company, participating in multiple innovative small-molecule drug R&D projects. Upon returning to China, he founded several biotechnology companies, including Shanghai Cosun Pharmaceutical, Sunco Bio, and Changche Bio, accumulating extensive R&D and management experience in fields such as CRO and drug development.

Below is a summary of the key points from Dr. Wen Jun’s speech:

The explosive growth of GLP-1 drugs has fueled the continued and steady expansion of the global market for peptide therapeutics. However, challenges persist in the manufacturing of peptide drugs, including high production costs, stringent purity control requirements, and technical difficulties associated with large-scale production.

Currently, the industrial-scale production of peptides primarily relies on two approaches: chemical synthesis and biosynthesis. Chemical synthesis offers a short development cycle and high customizability; however, for peptides comprising more than 30 amino acids, both synthetic complexity and product purification challenges increase significantly. Meanwhile, the industrial manufacturing of long-chain peptides faces capacity and technical bottlenecks, resulting in low overall yields and high costs. Biosynthesis utilizes yeast and Escherichia coli fermentation to produce peptide drugs, enabling targeted expression with safety and environmental benefits. Nevertheless, this approach encounters difficulties such as low efficiency in high-level peptide expression, susceptibility to proteolytic degradation, low productivity, and challenges in downstream purification.

To address these challenges, Paijin Biotech invented the TE-PEP tandem peptide expression technology.TE-PEP, an acronym for Tandem Expression of Peptides, is a technology that begins with peptide sequence design and utilizes high-level expression in Escherichia coli to produce recombinant proteins. These proteins are then extracted, solubilized, and enzymatically digested to yield the crude peptide drug product.According to Dr. Wen Jun, the purity of crude peptide drugs prepared using the TE-PEP technology platform is generally above 90%; after purification, the resulting peptide drugs achieve a purity greater than 99%.

TE-PEP offers multiple advantages and has a broad range of applications. It can be used to synthesize peptide drugs containing up to 100 amino acids, with high preparation yields. Each liter of fermentation broth can yield 5–10 grams of purified peptide drug with purity exceeding 99%, and the industrial production cost is significantly lower than that of chemical synthesis. Leveraging the TE-PEP technology platform, GMP-compliant peptide candidate drugs can be rapidly and efficiently prepared to meet IND filing requirements and subsequent clinical trial needs, thereby accelerating the drug approval and market launch process.

Leveraging the cost and technical advantages of its TE-PEP manufacturing platform, Paijin Biologics has strategically planned an annual production capacity of over 300 kilograms for semaglutide intermediate P29 peptide. The product boasts a purity level exceeding 98% and has obtained a US FDA Drug Master File (DMF) number (039617).

Based on the TE-PEP technology platform, Paijin Biopharma has established a portfolio of multiple peptide product pipelines targeting GLP-1 and GLP-2.

In the GLP-1 peptide drug project, Paijin primarily focuses on two major products: liraglutide and semaglutide.Currently, the semaglutide injection developed in collaboration with Huadong Medicine has completed enrollment of Phase III clinical trial participants and is progressing steadily. In addition to the injectable formulation, the company is also conducting R&D on oral GLP-1 preparations, including generic versions of semaglutide tablets and innovative formulations. The goal of the innovative formulation is to achieve a breakthrough in bioavailability, increasing it from the 0.5–1% range of Novo Nordisk’s original oral drug, Rybelsus, to approximately 5%. This improvement would significantly reduce the amount of semaglutide active pharmaceutical ingredient (API) required in the oral formulation, thereby lowering costs and enhancing drug accessibility for the benefit of patients with diabetes and obesity.

In its GLP-2 peptide drug project, Paijin Biopharma has adopted a dual strategy encompassing both generic and innovative drugs. Among these,GLP-2 Drug Teduglutide (PJ009) is a Biosimilar (Class 3.3) for the Treatment of SBS (Short Bowel Syndrome).

Short bowel syndrome (SBS) is a rare disease with an extremely low prevalence. Foreign literature reports an incidence of approximately 24.5 per 100,000 live births. In China, data from centers participating in the Chinese Short Bowel Syndrome Treatment Collaborative Group indicate a year-on-year increase in incidence; however, there are no precise nationwide incidence statistics. The overall incidence is estimated to be comparable to that reported abroad. In September 2023, short bowel syndrome was officially included in China’s “Second Batch of Rare Diseases Catalog.”

There remains a significant gap in the field of intestinal rehabilitation therapy in China. In February 2024, Takeda’s original teduglutide (brand name: Revestive) was officially approved by China’s National Medical Products Administration (NMPA) for adult and pediatric patients aged 1 year and older with short bowel syndrome (SBS). Although the original drug has been approved in China, the three-month treatment cost amounts to nearly RMB 400,000, making it prohibitively expensive and unaffordable for many families.

Paijin Biologics’ PJ009 demonstrates consistency with the originator drug in terms of structure, formulation, and preclinical characterization. The completed Phase I dose-escalation safety and tolerability study showed that PJ009 has a safety profile consistent with the originator drug and pharmacokinetic parameters similar to those of the originator.

In April 2024, Paijin registered and initiated the Phase III clinical trial of PJ009 (Recombinant Tirzepatide for Injection) on the CDE Clinical Trial Registration and Information Publicity Platform., and is expected to receive marketing approval in 2026. At that time, Paijin will provide a more affordable and highly effective treatment option for patients with short bowel syndrome (SBS) in China.

FT-1, a long-acting polypeptide drug developed by Paijin Biopharma as an innovative GLP-2 therapeutic agent for the treatment of SBS and the prevention of CID (chemotherapy-induced severe diarrhea), has been registered for clinical trial application.It is expected to receive approval and initiate Phase I clinical trials in humans in June.

Currently, Takeda’s tirzepatide requires once-daily subcutaneous injection for administration,Paijin Bio’s FT-1 is dedicated to the development of long-acting formulations, enabling once-weekly dosing to enhance drug accessibility and patient adherence.; Meanwhile, FT-1 has expanded its indication scope to include chemotherapy-induced diarrhea (CID). Severe diarrhea caused by chemotherapy is a common gastrointestinal adverse reaction in cancer patients undergoing chemotherapy. It not only reduces patients' quality of life but may also lead to electrolyte imbalances, dehydration, and infection, potentially resulting in shock and death in severe cases. Although there are currently some treatment options available, the efficacy of existing drugs remains limited. FT-1 has demonstrated excellent intestinal protective effects in animal models, holding promise as a new preventive option for CID.

In addition to its GLP-1 and GLP-2 programs, Paijin Biopharma has adopted a strategy combining imitation and innovation, building a robust product pipeline in therapeutic areas such as oncology, gout, and chemotherapy-induced thrombocytopenia.

2024 marks the 11th year since the establishment of Paijin Biopharma. Over the past decade, Paijin Biopharma has focused on the research, development, and manufacturing of innovative genetic engineering drugs, gradually building a comprehensive drug R&D and production system that encompasses drug discovery (R&D), drug manufacturing (GMP), chemistry, manufacturing, and controls (CMC), investigational new drug applications (IND), and expanding into new drug applications (NDA).

Dr. Wen Jun introduced that Paijin Bio has established core technology platforms leading the biopharmaceutical industry, including MAS-PEG, TE-PEP, and high-efficiency secretory expression in Pichia pastoris. The company holds a leading position in China in the fields of recombinant protein tool enzymes, diabetes therapeutics, PEGylation of therapeutic macromolecular proteases, and the industrialized production of peptide drugs. This dual capability in both R&D and manufacturing enables Paijin Bio to meet its own needs while leveraging years of technical accumulation and product development experience to provide comprehensive technical services and support to clients. These offerings include CRO/CDMO services spanning from preclinical research to commercial-scale production.

Currently, Paijin Bio’s CDMO facility spans nearly 4,000 square meters, with equipment capable of producing 10 grams to 1 kilogram of bulk drug substances and active pharmaceutical ingredients (APIs) for biologics, as well as filling 5,000 units for small- to medium-scale pilot formulation studies. The company offers comprehensive CRO/CDMO services that meet client needs across various drug development stages, including R&D, CMC, IND, and NDA.

In the future, Paijin Biotech will continue to innovate by accelerating drug development to benefit patients, while also advancing technology transfer to support the industrialization and growth of the peptide therapeutics industry.