Pulai Pharmaceuticals Submits IPO Prospectus: China's First Clinical-Stage Antimicrobial Peptide Developer Focused on High-Efficiency, Low-Toxicity Therapies

The growing resistance of pathogenic microorganisms to conventional antibiotics has become an increasingly serious problem, making the development of novel agents capable of inhibiting or killing these pathogens an ever more urgent task.

Antimicrobial peptides offer advantages such as rapid bactericidal action, a broad antimicrobial spectrum, minimal toxic side effects, and lack of immunogenicity. Furthermore, due to their unique mechanism of action, pathogenic microorganisms inhibited or killed by these peptides do not develop resistant strains, ensuring that their bactericidal efficacy is not compromised by drug resistance. Consequently, antimicrobial peptide-based therapeutics have emerged as ideal alternatives to antibiotics, garnering significant attention within the medical community.

Currently, peptide-based antimicrobial drugs available on the market include gramicidin and polymyxin. Chen Yuxin, Chairman of Pulai Pharmaceutical, stated, “The bactericidal efficacy of currently available antimicrobial peptide drugs is insufficient, and their use is significantly limited by high gastrointestinal and renal toxicity as well as substantial side effects.”

Pulai Medicine is dedicated to the research and development of next-generation antimicrobial peptide drugs. By leveraging the "cell membrane differentiation mechanism" of antimicrobial peptides and solid-phase peptide synthesis technology, the company redesigns antimicrobial peptide sequences to enhance bactericidal efficacy while reducing toxic side effects. Currently, the company has four antimicrobial peptide drugs in clinical stages. Among them,PL-5 is China’s first innovative antimicrobial peptide drug to enter clinical research; it has progressed to Phase II clinical trials and is indicated for refractory infections in open wounds caused by drug-resistant and susceptible bacteria.

Chen Yuxin stated, “Since the 1970s, no antibiotics with novel structures or mechanisms have been successfully developed, while bacterial resistance has continued to intensify, plunging the world into a ‘shortage’ of anti-infective drugs.”

It is reported that over 700,000 people worldwide die annually from antibiotic-resistant infections, a figure projected to reach 10 million per year by 2050. The World Health Organization (WHO) has identified antimicrobial resistance as “one of the greatest threats to global health, food security, and development today.” China has also released the National Action Plan for Containing Antimicrobial Resistance (2016–2020).

The threat of antibiotic resistance is becoming increasingly severe, making the development of novel anti-infective drugs one of the most urgent medical challenges.

Antimicrobial peptides exhibit broad-spectrum antibacterial activity, are less prone to inducing resistance mutations in target strains, and demonstrate potent bactericidal effects against bacteria, including certain drug-resistant pathogens. Consequently, they are considered promising ideal alternatives to antibiotics.

Chen Yuxin has many years of extensive experience in the research and development of antimicrobial peptide drugs. He studied abroad in Canada, where he earned a Ph.D. in Biochemistry, and subsequently completed his postdoctoral training at the University of Colorado School of Medicine in the United States.In the United States, Chen Yuxin first proposed the “cell membrane discrimination mechanism” of antimicrobial peptides and developed his first patented product, PL-5.

In 2007, Chen Yuxin returned to China with his patents. In 2009, he founded Jiangsu Pulei Pharmaceutical.

In China, approximately 75% of outpatients with colds are prescribed antibiotics, and the rate reaches as high as 95% among surgical patients. A World Health Organization survey indicates that the antibiotic usage rate among hospitalized patients in China is as high as 80%, with 58% receiving combination therapy involving two or more antibiotics—significantly exceeding the international benchmark of 30%. According to incomplete statistics, 10 of the top 15 drugs by consumption and sales volume in China are currently antibiotics.

It is precisely because China is a country with widespread antibiotic misuse that Chen Yuxin chose to return home to start a business, aiming to benefit more patients in China.

In 2014, Plai Pharma began submitting its application for clinical trial approval of PL-5 and entered the queue for review. Fortunately, by the end of 2015, the Chinese government had introduced multiple policies to encourage pharmaceutical innovation, significantly accelerating the drug approval process. As a result, Plai Pharma obtained approvals for Phase I, II, and III clinical trials in one go in 2016, saving considerable time.

Chen Yuxin stated bluntly, “Pulai Pharma has ridden the wave of a golden era for innovative drug development.”

Furthermore, the “National Action Plan to Contain Antimicrobial Resistance (2016–2020)” explicitly calls for intensified research and development efforts related to antimicrobial agents and supports the development of novel anti-infective drugs. Pulei Pharma’s antimicrobial peptide project has received support from government authorities at all levels.It has been included in the “Innovation Fund for Technology-based SMEs” projects of the Ministry of Science and Technology and the National Health and Family Planning Commission, as well as in the major new drug development projects under the 12th and 13th Five-Year Plans.

According to Chen Yuxin, Pulai Medicine has mastered effective antimicrobial peptide design methods,The company’s antimicrobial peptide drugs are all novel antimicrobial peptide molecules developed using de novo peptide design technology. By modifying the hydrophobicity, amphipathicity, and helicity of these peptides, their toxicity to the human body has been reduced.

Pulai Pharmaceutical has established a robust R&D team led by Dr. Michel, a Nobel Laureate, and Dr. Hawkins, a Fellow of the Royal Society of Canada. The company operates the Michel Biomedical (Jiangyin) Research Institute and the Robert (Jiangyin) Foreign Academician Workstation. It has developed multiple novel antimicrobial peptide candidates and secured relevant patent protections. Currently, the company maintains several R&D pipelines, including the antimicrobial peptides PL-5, PL-18, and PL-33, as well as the anticancer peptide PL-AC.

PL-5 Spray isNational Class I Innovative Anti-Infective Drug, isThe First Innovative Antimicrobial Peptide Drug to Enter Clinical Trials in China, suitable for infectious diseases of the skin and wounds, particularly for stubborn infections caused by drug-resistant bacteria. It demonstrates significant bactericidal advantages against "superbugs" with strong resistance to traditional antibiotics, including Pseudomonas aeruginosa, methicillin-resistant Staphylococcus aureus (MRSA), and NDM-1 gene-carrying multidrug-resistant Acinetobacter baumannii.

Phase I and Phase IIa clinical studies of PL-5 spray have been completed, and Phase IIb clinical trials are currently underway. Chen Yuxin stated, “Phase III clinical trials are expected to commence in 2020.”

PL-18 suppositories demonstrate excellent bactericidal and fungicidal efficacy. The related patent sequence has been granted PCT, U.S., European Union, and Chinese invention patents. It is understood that this candidate is being developed as a vaginal suppository for the treatment of gynecological infections caused by bacteria and fungi, particularly for refractory infectious diseases caused by drug-resistant strains. Preclinical studies are currently underway.

PL-33 eye drops exhibit good stability and are proposed for development as an ophthalmic formulation, indicated for ocular infectious diseases caused by various bacteria, Mycoplasma, and Chlamydia. Project initiation studies are currently underway.

PL-AC Injection, under Pulei Pharmaceutical, is a National Class I innovative anti-tumor new drug for which a Chinese invention patent has been applied.This agent demonstrates robust broad-spectrum antitumor activity, exhibiting potent anticancer effects against more than ten commonly encountered clinical tumor types evaluated in screening assays., intended for development as an injectable formulation. The design and synthesis of the compound, along with in vitro activity screening, have been completed, and preclinical studies are currently underway.

Antimicrobial peptide drugs can be administered via three routes: topical, oral, and injection. Currently, the main antimicrobial peptide products of Pulei Pharmaceutical are all for topical use. Chen Yuxin stated, “In our experiments, we found that antimicrobial peptides bind strongly to plasma albumin and do not dissociate after binding. Therefore, a certain concentration of antimicrobial peptides at the local lesion site is required to achieve therapeutic efficacy.” To address this issue, Pulei Pharmaceutical is currently engaged in peptide sequence modification to enhance the prospects for in vivo application of these peptides, with the aim of rapidly developing new varieties of antimicrobial peptides suitable for injection and oral administration.

Research on antimicrobial peptide drugs has been ongoing for approximately 40 years, yet no blockbuster drug has emerged to date. Chen Yuxin stated, “The development cycle and technical challenges associated with antimicrobial peptide drugs are unimaginable. We hope that more people will recognize the importance of these therapeutics and provide support or investment to the field of antimicrobial peptide drug development.”

Having cultivated the field of antimicrobial peptide therapeutics for over a decade, Pulay Pharma has emerged as a leader in this sector. Since its inception, the company has secured more than 10 patents, including PCT international invention patents and national invention patents from China, the United States, and the European Union. Additionally, it has undertaken more than 30 scientific and technological projects, such as those under the National Major New Drug Development programs during the 12th and 13th Five-Year Plan periods. In 2009, the company was recognized by the Overseas Chinese Affairs Office of the State Council as one of the first “Key Overseas Chinese Enterprise Teams.” In 2014, it was named a “China’s Most Promising Seed Enterprise” by Ernst & Young, one of the world’s largest accounting firms.

Meanwhile, Pulei Pharmaceutical has also attracted interest from multiple investment firms. Data from Tianyancha shows that the company has completed three rounds of financing, with investors including SDIC Venture Capital, Ginkgo Valley Capital, and Jincai Investment.

Given the lengthy development cycle and substantial capital investment required for new drug development, the company has developed a range of single-molecule antimicrobial peptide disinfection products. These products have been launched and are sold across China, generating annual sales revenue in the tens of millions, thereby providing financial support for the company’s new drug R&D projects.

Pulei Pharma firmly believes that antimicrobial peptides are an effective means of combating drug-resistant bacteria. In the future, building on its portfolio of antimicrobial peptide products, Pulei Pharma will maintain its balanced strength in both R&D and manufacturing, expand market presence with high-quality innovative products, and strive to become a global leader in the antimicrobial peptide pharmaceutical industry.

On September 20, 2019, Phase I of the Pulai Pharmaceutical Industrial Base was officially put into operation. Chen Yuxin revealed that the company would establish a new R&D center in Nanjing in 2020. Upon completion, the company’s R&D capabilities will be further strengthened, and its R&D pipeline will advance rapidly. Chen Yuxin expressed hope that PL-5 would be launched on the market within two to three years.