When given as a second- or third-line therapy, BeiGene’s tislelizumab is superior to docetaxel at prolonging the survival of people with locally advanced or metastatic non-small cell lung cancer (NSCLC), whose disease progressed while receiving platinum-based chemotherapy.
Additionally, tislelizumab had a favorable safety profile that was consistent with that of previous studies, and its use did not cause any new unexpected side effects.
These are the main findings of a planned interim analysis recommended by the independent data monitoring committee overseeing the company’s RATIONALE 303 Phase 3 trial (NCT03358875), which is ongoing at 123 clinical sites across 10 countries worldwide.
“The RATIONALE 303 trial is the third Phase 3 trial of tislelizumab in NSCLC that has achieved a positive outcome at interim analysis, and more importantly, marks the first global pivotal trial with a positive outcome in the tislelizumab clinical program,” Yong Ben, MD, chief medical officer at BeiGene, said in a press release.
“We look forward to sharing the full results at an upcoming medical conference and providing additional updates on our lung cancer program in the future,” he added.
Formerly known as BGB-A317, tislelizumab is an investigational checkpoint blockade antibody that binds to PD-1, a protein receptor found on the surface of immune T-cells that is often exploited by cancer cells to evade immune attacks.
Unlike other anti-PD-1 antibodies, tislelizumab has also been designed to minimize binding to the Fc-gamma receptor found on the surface of macrophages, thereby preventing macrophages from wrongly engulfing cancer-killing T-cells. Of note, macrophages are immune cells responsible for removing dead cells and debris from tissues.
In China, tislelizumab has been approved to treat patients with classical Hodgkin’s lymphoma, and those with advanced urothelial carcinoma. The medication is under review in the country for other indications, including as a first-line therapy for squamous and non-squamous NSCLC, in combination with chemotherapy. So far, the therapy has not been approved for any indication outside China.
“As we continue to advance tislelizumab in its broad clinical program, which targets a wide range of prevalent cancer types, we expect to see a growing body of clinical evidence that we believe will help further evaluate this potentially differentiated checkpoint inhibitor and support potential regulatory filings in China and globally,” Ben said.
RATIONALE 303 is one of 12 ongoing Phase 3 trials of tislelizumab in China and worldwide. The trial enrolled a total of 805 adults with NSCLC, who were randomly assigned to receive intravenous injections of tislelizumab, or docetaxel, every three weeks.
The study’s main goal is to assess whether tislelizumab is superior to docetaxel at extending overall survival in the overall population of trial participants, as well as in those whose tumors contained high levels of the PD-L1 protein.
Interim data from RATIONALE 303 now announced by BeiGene revealed this goal was attained in the overall population.
Secondary study goals include assessing the proportion of patients responding to treatment, the duration of their responses, the time patients live without signs of disease worsening, and the therapy’s safety.
RATIONALE 303 is expected to conclude by June 2021.
