Frontline Tislelizumab/Chemo Approved in China for Advanced Squamous NSCLC

The China National Medical Products Administration (NMPA) has approved tislelizumab (BGB-A317) for use in combination with 2 chemotherapy regimens in the frontline treatment of patients with advanced squamous non–small cell lung cancer (NSCLC).¹

The regulatory decision was based on data from the phase 3 BGB-A317-307 trial (NCT03594747) that were presented during the 2020 ASCO Virtual Scientific Program and showed that combining the anti–PD-1 inhibitor with chemotherapy in the frontline setting improved progression-free survival (PFS) versus chemotherapy alone in Chinese patients with advanced squamous NSCLC.²

Among participants with a PD-L1 expression of less than 1%, the median PFS with tislelizumab plus paclitaxel/carboplatin (arm A) was 7.6 months versus 5.5 months with paclitaxel/carboplatin alone (control arm; arm C; HR, 0.636; 95% CI, 0.368-1.101). In those who received tislelizumab plus nab-paclitaxel (Abraxane) plus carboplatin (arm B), the median PFS was 7.4 months (HR vs control, 0.692; 95% CI, 0.406-1.178).

In patient who had a PD-L1 expression between 1% and 49%, the median PFS was 7.6 months versus 4.2 months in arm A and arm C, respectively (HR, 0.439; 95% CI, 0.221-0.870). In arm B, the median PFS was not evaluable (HR vs control, 0.311; 95% CI, 0.145-0.664).

In those who had a PD-L1 expression of greater than 50%, the median PFS in arm A and arm C were 7.6 months versus 5.5 months, respectively (HR, 0.501; 95% CI, 0.282-0.891). In arm B, the median PFS was also 7.6 months (HR vs control, 0.425; 95% CI, 0.232-0.776).

“Lung cancer is the leading cause of cancer-related death in China, and with NSCLC comprising the most common form of the disease, there is significant patient need. We are grateful to have a new treatment available in the front-line setting for patients with advanced squamous NSCLC,” Jie Wang, MD, PhD, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, stated in a press release. “In its phase 3 trial in this indication, tislelizumab combined with standard chemotherapy demonstrated a clinically meaningful benefit as assessed by PFS and response rates.”

The open-label, randomized, phase 3 trial enrolled a total of 360 patients from mainland China who had untreated stage IIIB/IV squamous NSCLC, irrespective of PD-L1 expression. The majority of patients, or 66.1%, had stage IV disease, while 33.9% had stage IIIB disease. The most frequently confirmed distant metastatic sites comprised the bone (16.9%), liver (12.2%), and brain (1.7%). With regard to PD-L1 expression, 40% had an expression of less than 1%, 25.3% had an expression between 1% and 49%, and 34.7% had an expression of greater than 50%.

Participants were randomized 1:1:1 to 1 of 3 treatment arms. Patients in arm A were given tislelizumab at a dose of 200 mg every 3 weeks in combination with paclitaxel/carboplatin. Those in arm B received tislelizumab at the same dose/schedule plus nab-paclitaxel/carboplatin, while those in arm C just received paclitaxel/carboplatin alone. Paclitaxel, nab-paclitaxel, and carboplatin were given for 4 to 6 cycles. Tislelizumab was administered until either progressive disease, unacceptable toxicity, or discontinuation.

Notably, crossover was allowed if patients progressed on the control arm. The primary objective of the research was PFS, while secondary end points comprised objective response rate (ORR), duration of response, OS, and safety.

Additional data revealed an ORR of 73% in arm A, versus 75% and 50% in arm B and arm C, respectively. In arm A, the ORR consisted of a 4% complete response (CR) rate and a partial response (PR) rate of 68%; 15% of patients achieved stable disease with this regimen, while 10% experienced disease progression. In arm B, the ORR consisted of a CR rate of 3% and a PR rate of 72%, with 16% of patients experienced disease stability and 4% experiencing disease progression.

Regarding safety, 86.7% of patients in arm A experienced adverse effects (AEs) associated with tislelizumab; these effects were reported in 88.1% of those on arm B. Grade 3 or greater toxicities associated with the anti–PD-1 inhibitor occurred in 36.7% of those on arm A and 40.7% of those on arm B. Moreover, serious treatment-related toxicities were reported in 27 patients on arm A, 28 on arm B, and 17 on arm C. Treatment-related AEs that resulted in death in arms A, B, and C, occurred in 1 patient, 2 patients, and 3 patients, respectively.

The regulatory decision also follows recently reported findings from the phase 3 RATIONALE-303 trial (NCT03358875) in which tislelizumab improved OS over docetaxel when used in the second- or third-line treatment of patients with locally advanced or metastatic NSCLC who had progressed on prior platinum-based chemotherapy, meeting the primary end point of the research.³ Notably, the agent was also found to be safe in this population.

References

1. China National Medical Products Administration approves tislelizumab in combination with chemotherapy in first-line advanced squamous non-small cell lung cancer. News release. BeiGene, Ltd. January 13, 2021. Accessed January 14, 2021. http://bwnews.pr/3qpPOBF.

2. Wang J, Yu X, Lu S, et al. Phase III study of tislelizumab plus chemotherapy vs chemotherapy alone as first-line (1L) treatment for advanced squamous non-small cell lung cancer (sq NSCLC). J Clin Oncol. 2020;28(suppl 15):9554. doi:10.1200/JCO.2020.38.15_suppl.9554

3. BeiGene announces that RATIONALE 303 trial of tislelizumab in non-small cell lung cancer met the primary endpoint of overall survival at interim analysis. News release. BeiGene, Ltd. November 17, 2020. Accessed January 14, 2021. https://bit.ly/3lGDLOb.