Shanghai Yingli Pharmaceutical Co., Ltd. (Yingli Pharma) announced topline results of a Phase II registration study of linperlisib, a PI3Kδ inhibitor, for the treatment of relapsed/refractory follicular lymphoma (FL). Linperlisib is a potent and highly selective oral PI3Kδ inhibitor that was developed for potentially more efficacious with a potentially more manageable and differentiated safety profile  from other PI3Kδ class agents. The topline results of this single-arm Phase II study (NCT04370405) showed that linperlisib treatment led to significant clinical improvement  for the patients with relapsed/refractory FL.

The results of the study indicated an 80.9% overall response rate (95% confidence interval, 71.2-88.5%) for 89 evaluable relapsed/refractory FL patients, as a primary outcome measure assessed by an Independent Review Committee (IRC). In addition, a disease control rate (DCR) of 96.6% was observed. Safety data demonstrated that linperlisib 80mg QD dosing regimen was well tolerable and manageable with a differentiated and favorable safety profile.

Responding to the topline data of this Phase II registration study, Dr. Qiu Lugui of Institute of Hematology & Blood Diseases Hospital, Tianjin, China, and the leading Investigator on the clinical study, stated: "The Phase II clinical trial of linperlisib for the treatment of relapsed/refractory follicular lymphoma has demonstrated striking clinically meaningful results, suggesting that this new PI3Kδ selective inhibitor may be very well differentiated from marketed PI3Kδ inhibitors available outside of China. It is encouraging that infrequent and manageable adverse events were observed for linperlisib, indicative of the agent being safe and well-tolerated for relapsed/refractory FL patients. We are hopeful that linperlisib may soon be made available as a valuable treatment option for this serious disease, bringing hope to these patients and their families."

"We are very excited that linperlisib has demonstrated such outstanding therapeutic benefit in relapsed/refractory follicular lymphoma. These findings give us confidence in the performance of linperlisib for our other ongoing clinical studies for different types of tumors," said Dr. Xu Zusheng, President, Research and Development of Yingli Pharma. "We look forward to bringing this PI3Kδ inhibitor that has been premiered in China, into global development for patients around the world."

Full analysis of the data from the study will be forthcoming through medical conferences and publications and can be followed on the Yingli Pharma website. Yingli Pharma is planning to submit an NDA application to NMPA based on the results of this registration study.

About Linperlisib

Linperlisib (YY-20394) is a highly selective PI3Kδ inhibitor that has shown superior efficacy, PK, and good pharmaceutical properties in preclinical research as an oral once-a-day agent. Linperlisib received FDA Orphan Drug Designations for FL and CLL/SLL and has an IND for a Phase II study in r/r FL in the United States. Linperlisib  was awarded NMPA Breakthrough Therapy status in China. Additional linperlisib clinical trials are ongoing in PTCL, other lymphomas, solid tumors, and in combination with gemcitabine/oxaliplatin in r/r DLBCL.

About follicular lymphoma

Follicular lymphoma (FL) is the second most common type of NHL worldwide and accounts for 10-20% of NHL in China. Although FL is generally an indolent disease on diagnosis, the relapsed and refractory forms of FL are more aggressive and require innovative therapies. Dr. Qui reflected on the status of FL treatments, "In recent years, immunochemotherapy has gradually replaced chemotherapy and radiotherapy for the initial treatment of FL and other lymphomas. However, because patients progress on frontline therapies, safe and efficacious agents are needed to prolong treatment benefit for these lymphoma patients."

About Yingli Pharma

Yingli Pharma, a clinical stage innovative biopharmaceutical company, is developing best-in-class and first-in-class oral investigational agents for the treatment of cancer, metabolic and autoimmune diseases. In addition to linperlisib, Yingli Pharma currently has two other investigational agents in clinical development. More investigational agents are in IND-enabling and preclinical stages of development.