China’s water‑based adjuvant bivalent inactivated vaccine against Porcine Circovirus Type 2 and Mycoplasma hyopneumoniae has been officially launched.

On November 6, 2018, a grand launch event was held in Luoyang for the water-adjuvanted bivalent inactivated vaccine against Porcine Circovirus Type 2 and Mycoplasma hyopneumoniae, which was the result of eight years of research and development. This vaccine was meticulously developed by Luoyang Huizhong Biotechnology Co., Ltd., leveraging the expertise of the National Engineering Research Center for Veterinary Drugs.

Luoyang Huizhong Biotechnology Co., Ltd. is a wholly owned subsidiary of Placor Bioengineering Co., Ltd., a leading domestic innovator in animal health technology. Established in 2011, the company was founded on the successful 20-year legacy of Luoyang Huizhong Veterinary Medicine and the 10-year track record of Placor Bio. In May 2015, it passed the GMP inspection conducted by the Ministry of Agriculture. The company is primarily engaged in the research, development, production, and marketing of veterinary biological products and pharmaceuticals, and is recognized as a high-tech enterprise whose innovation capabilities and overall strength rank among the industry’s top. Adhering to the corporate philosophy of “Innovation Shapes the Future, Integrity Drives Steady Growth,” Huizhong Biotechnology leverages the research platform of the National Engineering Research Center for Veterinary Pharmaceuticals to translate scientific and technological advances into practical applications.

HuiZhong Bio has successively obtained eight national-level new veterinary drug certificates and been granted more than six national invention patents. The company has also successfully developed the “One-Day-Old Immunization Expert”—a novel trivalent inactivated vaccine—and a domestically produced water‑adjuvanted bivalent inactivated vaccine for porcine circovirus type 2 and mycoplasma pneumonia, providing robust technological and product support for advancing China’s veterinary pharmaceutical industry, controlling animal diseases, and ensuring the safety of livestock products.

The “Bivalent Inactivated Vaccine against Porcine Circovirus Type 2 and Mycoplasma hyopneumoniae” now being launched is a major scientific and technological achievement attained by Huizhong Biotechnology Co., Ltd. in line with its business philosophy of “upright and prudent management” and its development strategy of “innovation shapes the future.” Leveraging the National Engineering Research Center for Veterinary Drugs as its technological platform, the product boasts independent intellectual property rights and has been granted a national registration certificate for new veterinary medicines. This breakthrough represents another significant milestone, following Huizhong’s adjuvanted inactivated vaccine against Porcine Circovirus Type 2 (SH strain II), and is the result of sustained innovation and practical application.

Huizhong Bio’s water‑adjuvanted inactivated vaccine against Porcine Circovirus Type 2 (SH strain II) has pioneered the domestic market for water‑adjuvanted whole‑virus inactivated vaccines. Since its successful launch, the product has played a pivotal role in the prevention and control of porcine circovirus disease in China, delivering significant economic and social benefits. Leveraging the National Veterinary Drug Engineering Technology Research Center, the company continues to advance research and development and to upgrade its manufacturing processes, striving to create even more innovative and safer vaccines.

The project team leveraged a proprietary water-based adjuvant in conjunction with advanced vaccine‑production processes to effectively mitigate risks associated with incompatibility between the adjuvant and antigens, as well as issues related to stability and uniformity, following the mixing of individual components. They successfully isolated, evaluated, and screened mycoplasma strains exhibiting favorable immunogenicity and growth characteristics, and developed a safe, highly effective aqueous adjuvant suitable for both antigens. This approach resolved three major technical challenges concerning the compatibility of PCV2 and mycoplasma antigens, culminating in the successful development of China’s first bivalent inactivated vaccine based on an aqueous adjuvant, targeting porcine circovirus type 2 and Mycoplasma hyopneumoniae. The successful R&D and commercialization of this product hold significant practical importance for advancing industry‑wide technological progress and product upgrades, thereby enhancing disease prevention and control capabilities.

Project Background:

Porcine circovirus type 2 (PCV2) can cause a range of diseases, including post-weaning multisystemic wasting syndrome (PMWS), porcine dermatitis and nephropathy syndrome (PDNS), porcine respiratory disease complex (PRDC), reproductive failure in sows (PRF), and congenital tremor in piglets (CT). Moreover, PCV2 readily co‑infects with other pathogens or leads to secondary infections, further complicating clinical presentations and resulting in substantial economic losses for pig farms, thereby imposing a severe impact on the global swine industry.

Mycoplasma pneumonia in pigs is a chronic respiratory disease caused by infection with Mycoplasma hyopneumoniae, also known as “swine asthma” or “enzootic pneumonia.” After entering the porcine respiratory tract, Mycoplasma hyopneumoniae gradually establishes an infection, leading to severe inflammatory damage. In some lung regions, this manifests as consolidation, fibrosis, and necrosis, resulting in impaired pulmonary function, respiratory distress, and reduced feed conversion efficiency. Piglets are particularly susceptible, and the disease is characterized by high incidence and high transmissibility, inflicting substantial economic losses on the global swine industry.

In recent years, as China’s agricultural and pastoral industrialization reforms have deepened, the sustainable development of the country’s livestock sector has been strongly promoted, leading to substantial increases in both the diversity and numbers of livestock and poultry. At the same time, the variety and incidence of animal diseases have risen markedly. In clinical practice, mixed infections are common, with co-infection by porcine circovirus type 2 and Mycoplasma hyopneumoniae being particularly prevalent. Consequently, combination vaccines capable of preventing multiple diseases have become a major trend in the development of veterinary biologics and an urgently needed product for livestock producers. Although well‑established monovalent vaccines are available for each of these pathogens, their numerous formulations and complex vaccination schedules pose challenges. A combined vaccine targeting porcine circovirus type 2 and Mycoplasma hyopneumoniae can address many of the limitations associated with using separate vaccines, delivering dual protection in a single dose while saving time and effort.

Product Advantages:

The bivalent inactivated vaccine against Porcine Circovirus Type 2 and Mycoplasma hyopneumoniae, developed with fully independent intellectual property rights, was the first to complete product development and obtain a new veterinary drug registration certificate. A proprietary water-based adjuvant, combined with advanced vaccine‑production technology, ensures the quality of this combination vaccine, effectively mitigating risks such as adjuvant–antigen incompatibility and poor stability and uniformity that can arise when single‑component vaccines are mixed.

1. Domestically isolated strains are better suited to Chinese pig farms: For Mycoplasma hyopneumoniae, the domestically isolated epidemic strain HN0613 is used. Nucleotide sequence analysis of the R1 region of the P97 gene reveals that this strain exhibits a much higher degree of homology with domestic isolates than with foreign strains. Both laboratory challenge studies and field use have demonstrated its excellent immunogenicity and protective efficacy, providing more comprehensive protection and greater suitability for Chinese pig farms.

2. Antigen purification without interference, resolving compatibility challenges: By optimizing the culture medium formulation and fermentation parameters, we overcame the technical hurdles of high‑density mycoplasma fermentation, achieving a stable cell density of 5.0 × 10^9 CCU/mL. Employing tangential flow ultrafiltration and other purification processes, we completely removed porcine circovirus type 2 antibodies from the porcine serum used in mycoplasma cultivation, attaining a contaminant protein removal rate of 99% and thereby avoiding any interference with the immune response against circovirus, thus addressing the compatibility issue between the two antigens. For the circovirus antigen, we utilized PK15‑B1 susceptible clone cells, yielding a titers ≥ 1.0 × 10^7.0 TCID50 per dose. Through tangential flow ultrafiltration and other purification steps, the contaminant protein removal rate exceeded 99%, and the antibody titers in post‑vaccination pig sera were comparable to those of imported vaccines.

3. A specially formulated adjuvant is优选, enabling simultaneous use with two antigens: The adjuvant in this product (Freemix™‑Gel Adjuvant) is prepared as nanospheres using a colloidal high‑molecular‑weight crosslinked copolymer, with a positively charged surface. Through electrostatic adsorption, it effectively binds the negatively charged PCV2 and mycoplasma antigens, forming an adjuvant–antigen complex that is readily recognized and processed by immune cells. Over 90% of the nanoparticles have diameters below 1,000 nm, facilitating rapid recognition by antigen‑presenting cells, thereby initiating and activating a robust immune response and ensuring swift protective immunity following vaccination. Moreover, the nanoparticles feature a porous, network‑like internal structure that encapsulates both antigens, enabling sustained, slow release and providing an immunity duration exceeding four months.

Economic and social benefits:

The approval of a novel bivalent inactivated vaccine against Porcine Circovirus Type 2 and Mycoplasma hyopneumoniae marks the culmination of Huizhong Bio’s unwavering commitment to technological innovation and its sustained increase in R&D investment. This achievement not only underscores the company’s robust innovative capabilities but also drives the upgrading and replacement of swine vaccines in the industry, expands the company’s product portfolio, reinforces its pioneering position in porcine circovirus vaccines, and significantly enhances its overall competitiveness within the sector—thereby creating new growth drivers for the company.

The bivalent inactivated vaccine against Porcine Circovirus Type 2 and Mycoplasma hyopneumoniae is a cutting-edge product that leverages a proprietary adjuvant and advanced vaccine‑production technologies to prevent diseases caused by these pathogens. Upon its market launch, it will accelerate the swine vaccine industry’s transition into the era of combination vaccines, further strengthening Huizhong Bio’s competitive edge in the swine vaccine market while driving technological advancement in China’s animal vaccine sector, thereby providing robust technical and product support for national livestock disease prevention and control and the production of safe animal‑derived food products.

Technical Supporting Unit: Overview of the National Veterinary Drug Engineering Technology Research Center

The National Engineering Research Center for Veterinary Pharmaceuticals is an industry‑wide public R&D platform established with the approval of the Ministry of Science and Technology and based at Placor Co., Ltd. The center boasts over 18,000 square meters of R&D laboratories and a supporting animal facility, and comprises multiple research institutes specializing in animal vaccines, diagnostic reagents, bioengineering, process technology, and veterinary pharmaceuticals. It is home to a national-level enterprise technology center, a national–local joint engineering laboratory for the development of diagnostic reagents and vaccines for animal infectious diseases, a postdoctoral workstation, an academician workstation, and world‑class R&D and ancillary facilities. Led by Dr. Tian Kegong, Director of the World Organisation for Animal Health’s Reference Laboratory for Highly Pathogenic Porcine Reproductive and Respiratory Syndrome, the center has assembled a distinguished R&D team of more than 200 experts, possessing the capability to conduct systematic, integrated, and engineering‑oriented research and development on critical, foundational, and cross‑cutting industrial technologies.

Over the past three years, the center’s R&D investment has accounted for more than 10% of the company’s sales revenue, and it has achieved a leading domestic position—and an internationally advanced level—in gene‑engineering vaccine technology, multivalent and combination vaccine technology, high‑throughput diagnostic reagent technology, and chemical API synthesis technology.