Fapon Biopharma has achieved a significant milestone in immuno-oncology by enrolling the first patient in China for its Phase I clinical trial of FP008, a first-in-class anti-PD-1 × IL-10M fusion protein designed for advanced solid tumors. The enrollment took place at Zhejiang Cancer Hospital, with the patient completing the Dose Limiting Toxicity (DLT) observation period and demonstrating a favorable safety profile.
Novel Mechanism Addresses Treatment Resistance
FP008 represents the latest generation of immuno-oncology approaches, engineered as a novel anti-PD-1 × IL-10M fusion protein designed to overcome the limitations of current PD-1 inhibitors. The therapy utilizes a proprietary IL-10 mutant that eliminates the toxicity associated with the wild-type protein, potentially offering a new therapeutic option for patients who are refractory to or relapsed from anti-PD-1/PD-L1 therapies.
The unique mechanism of action involves IL-10 monomer (IL-10M) engineering that significantly reduces hematologic toxicity, while the anti-PD-1 antibody enhances IL-10M activity through PD-1 targeted enrichment and cis-activation. This breakthrough design could potentially transform the treatment paradigm for solid tumors by providing new options for patients with limited therapeutic choices.
Promising Preclinical Results
Preclinical studies have demonstrated that FP008 significantly reduces PD-1 antibody-mediated CD8⁺ T-cell exhaustion and exhibits potent anti-tumor efficacy. Key findings from these studies include enhanced infiltration of CD8⁺ T-cells into tumors, reduced terminal exhaustion differentiation of CD8⁺ T-cells, and increased secretion of IFN-γ and GZMB in terminally exhausted CD8⁺ T-cells.
The therapy also showed favorable safety and pharmacokinetic profiles in cynomolgus monkey studies, supporting its clinical potential. These positive preclinical results have contributed to FP008 receiving Investigational New Drug (IND) approval from both the U.S. FDA and China's NMPA.
Multi-Center Trial Design
The multi-center Phase I trial in China is being led by Zhejiang Cancer Hospital, with two additional sites participating. The trial aims to evaluate the safety and tolerability of FP008 in patients with advanced solid tumors. Professor Zhengbo Song, Principal Investigator at Zhejiang Cancer Hospital, expressed optimism about the therapy's potential, stating: "FP008 offers a promising therapeutic strategy for solid tumor patients resistant to anti-PD-1 antibodies. Its unique mechanism could address a critical unmet clinical need in immuno-oncology. We look forward to further evaluating its safety and efficacy in the clinic."
Strategic Development Approach
Fapon Biopharma is actively seeking strategic partnerships with biopharmaceutical companies worldwide to co-develop FP008 through clinical trials or further commercialization. The company specializes in discovering and developing biologics for cancer treatment, autoimmune diseases, and other conditions with unmet medical needs.
The company has built advanced drug discovery platforms, including an antibody discovery platform based on mammalian cell display technology, a platform for generating IL-10M fusion proteins, and a TCE platform based on cross-species CD3 nanobody technology. These capabilities cover the entire drug development process from discovery through early clinical development, positioning the company to deliver safer, more efficacious, and accessible biologics.
