The open-label, randomized, dose optimization phase 2 study aims to enroll participants in multiple countries to further clarify the optimal dosage, effectiveness, and safety of RC88 monotherapy in the treatment of patients with platinum-resistant recurrent epithelial ovarian, fallopian tube, and primary peritoneal cancers.

Independently developed by RemeGen, RC88 is a novel ADC drug targeting mesothelin (MSLN), it consists of a recombinant humanized anti-MSLN monoclonal antibody linked to the microtubule inhibitor monomethyl auristatin E (MMAE), which acts as a microtubule inhibitor. RC88 has high affinity for MSLN and can specifically bind to overexpressing MSLN tissues and has clearly displayed a terminating effect on tumor cells with various expression levels of MSLN.

As the Company advances RC88's clinical development, Dr. Jianmin Fang, CEO of RemeGen, shares his insights: "The approval of RC88's IND application by the FDA marks a pivotal moment in our commitment to addressing the challenges of platinum-resistant recurrent ovarian cancer. Our focus remains on developing innovative treatments that can significantly improve patient outcomes in areas with critical unmet needs. RC88, with its unique targeting mechanism, exemplifies our dedication to pioneering advancements in cancer therapy."

RC88's unique strategy to address Platinum-Resistant Recurrent Ovarian Cancer (PROC)

Epithelial ovarian cancer (EOC) remains a significant cause of cancer deaths among women, with no effective screening methods. When diagnosed, over 70 percent of patients have already reached an advanced stage, with most patients relapsing within two years. As the interval between relapses gradually shortens, these patients eventually progress from platinum-sensitive to platinum-resistant relapses.

Treatment of EOC relies on satisfactory cytoreduction and platinum-based chemotherapy and although most advanced ovarian cancers are initially platinum-sensitive, almost all patients eventually develop platinum resistance, resulting in limited overall survival and extremely limited treatment options and poor prognosis for patients with platinum-resistant recurrent ovarian cancer (PROC). Moreover, chemotherapy drugs are highly toxic with patients unable to tolerate multiple lines which has created a dilemma and challenge in the treatment of recurrent ovarian cancer meaning more effective treatment options are necessary to improve the quality of life of patients.

The later the stage and the more aggressive the ovarian cancer, the higher the expression rate of mesothelin which is what makes RC88 unique in that it specifically targets mesothelin. In EOC, the expression rate of MSLN can be higher, up to 97 percent. The differential expression of MSLN in tissue tissues and normal tissues makes it a natural and highly potential drug target. There are currently no other ADC drugs targeting mesothelin on the market bolstering RemeGen's commitment to providing solutions for the great unmet clinical need of patients suffering from life-threatening illnesses globally.

Furthermore, this year marked a significant advancement with the approval of the Phase I/II clinical study of RC88 combined with Sintilimab in treating advanced malignant solid tumors.