YouhuiKang Biopharma Files for IPO: Pioneering Recombinant Protein Therapeutics from Assisted Reproduction to Stroke

Youhuikang Biotech, founded in 2016, is a company with extensive experience in the research and development of innovative protein-based therapeutics. It is dedicated to developing recombinant protein drugs that address critical unmet medical needs. The company has established advanced R&D and pilot-scale production platforms encompassing molecular biology, cell culture and manufacturing, recombinant protein purification, and quality control, thereby possessing full-chain industrialization capabilities from R&D and pilot-scale production to Investigational New Drug (IND) application.

Dr. Hou Yongmin, founder of Youhuikang Bio, holds a Ph.D. from the University of Toronto and completed his postdoctoral training at the University of Washington. He has over 25 years of experience in the research, development, and industrialization of biologics both domestically and internationally. Dr. Hou spent more than 13 years engaged in R&D at Yale University, UC Berkeley, and Schering-Plough Pharmaceuticals (USA), with research focusing on novel target discovery and the construction and production of recombinant proteins. Upon returning to China, Dr. Hou served as Chief Scientific Officer at Tianpu Pharmaceutical, where he led the development of multiple innovative protein therapeutics, including Kailikang, a Class 1 new drug for stroke treatment.

Under the leadership of Dr. Hou Yongmin, UHikang Bio has overcome various challenges in protein engineering, breaking through technical bottlenecks that hindered the commercialization of complex glycosylated and low-yield proteins. The company has established a high-yield recombinant protein drug production platform based on mammalian cells, with core technologies including the UZyme high-efficiency expression system and γBloc Fc long-acting technology. Specifically, the UZyme high-efficiency expression system targets difficult-to-express proteins, particularly glycosylated hydrolases with low expression levels, achieving over a hundred-fold increase in yield and significantly reducing commercial production costs. The γBloc Fc long-acting technology is designed for complex glycosylated proteins to extend half-life while avoiding potential ADCC/CDC side effects. This long-acting technology can also be applied to antibody development, achieving gram-level protein expression and reaching an internationally leading standard.

Leveraging this technology platform, Youhuikang Biotech has currently established its pipeline primarily in the fields of assisted reproduction and infertility, stroke, and other areas. The company has independently developed multiple recombinant protein drugs, including three first-in-class (FIC) innovative drugs.

Ovulation-inducing agents are primarily indicated in clinical practice for women with ovarian dysfunction and those requiring the development of multiple follicles in a single cycle. The former group typically includes women with menstrual irregularities (oligo-ovulation) or amenorrhea (absence of menstruation or cessation of ovulation), who use short-acting ovulation-inducing medications to induce or restore normal ovarian ovulation. The latter group generally consists of female partners in infertile couples undergoing assisted reproductive technology (ART); they receive ovulation-inducing stimulation to achieve controlled ovarian hyperstimulation, aiming to ensure that at least one oocyte is fertilized and results in a successful pregnancy.

However, in the second category of indications, a single administration of short-acting ovulation-inducing agents typically stimulates the patient’s ovaries for only 1–2 days. Since normal follicular development from initiation to maturity requires a 10-day cycle, female patients undergoing assisted reproductive technology (ART) must receive consecutive daily injections of ovulation-inducing agents over this 10-day period to successfully achieve controlled ovarian hyperstimulation, thereby improving fertilization and pregnancy success rates. This continuous dosing regimen necessitates frequent hospital visits, which not only increases the comprehensive costs associated with transportation, accommodation, and family caregiving during the ART cycle but may also lead to adverse reactions due to the high frequency of administration, significantly reducing patient compliance.

Thus, it is evident that there has been a persistent clinical demand for long-acting ovulation-inducing agents in assisted reproductive technology; however, no such long-acting agents have yet been approved for marketing in China. Follicle-stimulating hormone (FSH) represents the largest category of ovulation-inducing drugs. Elonva (FSH-CTP), the first long-acting FSH product independently developed by Merck, was successfully launched in the European Union in 2010 but has not yet entered the Chinese market.

Why Has No Long-Acting FSH Been Launched in China? The Underlying Challenge Lies in the Technical Barriers of Recombinant Protein Development Processes for Long-Acting FSHHou Yongmin, founder of Youhuikang Biotech, told VCBeat that each protein possesses a unique glycosylation structure, and the Fc fusion strategy varies from one protein to another. Unlike antibody platforms, which can leverage validated universal sites to enable platform-based antibody drug development, long-acting FSH cannot be developed through such a standardized approach.

Furthermore, how should recombinant proteins be modified? At which site should the recombinant fusion be incorporated? What is the protein expression density? Each of these steps requires extensive and meticulous validation, consuming significant time and effort. Youhuikang Biotech dedicated ten years to this phase, ultimately developing “UN008,” a long-half-life, high-activity drug that holds promise as China’s first long-acting FSH formulation to meet clinical needs.

UN008, a first-in-class (FIC) novel drug in the field of assisted reproduction, is Youhuikang Biotech’s most advanced recombinant protein pipeline candidate. It has already received Investigational New Drug (IND) approval and is actively undergoing clinical trials.

UN008, an Fc variant fusion protein, is expected to extend the half-life of follicle-stimulating hormone (FSH) to approximately seven days, aligning with the follicular development cycle. This enables it to replace frequent administrations of short-acting ovulation-inducing drugs while avoiding the side effect of ovarian hyperstimulation syndrome (OHSS). Youhuikang Bio’s γBloc Fc long-acting technology ensures FSH activity while mitigating potential adverse effects associated with antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC), achieving expression levels at the gram scale.

In addition to UN008, Youhuikang Biopharma has also established a pipeline of assisted reproductive and infertility drugs targeting ovulation induction, ovarian stimulation, and male infertility, which is currently in the preclinical research stage.

In addition to its strategic layout in the field of assisted reproduction, the company has another core pipeline product, UN006, targeting the stroke market. Developed based on Youhuikang Bio’s UZyme high-efficiency expression system, UN006 is the first recombinant protein drug in China that targets KN. Its primary mechanism of action involves improving patient blood circulation by activating nitric oxide (NO) and prostacyclin pathways. Youhuikang Bio has optimized the route of administration and dosage form: intravenous injection of UN006 during the acute phase, and subcutaneous injection during the recovery phase. This approach facilitates self-administration by patients after discharge during the recovery period, reduces the frequency of dosing, and significantly improves medication adherence.

For stroke, current standard guideline-recommended treatments include thrombolysis or endovascular mechanical thrombectomy (MT). Intravenous thrombolytic agent tPA is indicated within 4.5 hours of symptom onset, while endovascular mechanical thrombectomy (MT) is only suitable for large vessel occlusions. These approaches are applicable to approximately 20% of stroke patients, leaving 80% without effective treatment options. In contrast, UN006 has a therapeutic window exceeding 24 hours, is suitable for more than 80% of patients, and significantly reduces the recurrence rate by 86%. Comparable investigational products in the United States have entered Phase II/III clinical trials (under the FDA’s Fast Track designation).

Meanwhile, Youhuikang Biotech has also deployed recombinant tPA, a thrombolytic agent, in the stroke sector, aiming to meet the needs of stroke patients across various therapeutic windows.

It is reported that Youhuikang Biotech is currently collaborating with Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School, to conduct clinical trials evaluating the safety and efficacy of UN008, a novel Class 1 drug for assisted reproduction. Meanwhile, the company is actively preparing an Investigational New Drug (IND) application for its stroke therapeutic candidate, UN006. In parallel, Youhuikang has launched a new round of financing to advance the clinical development of UN008, complete the IND filing for UN006, and expand into additional targets based on its proprietary technology platform.