Tislelizumab is a humanized IgG4 anti-PD-1 monoclonal antibody specifically designed to minimize binding to FcγR on macrophages.
Frontline tislelizumab plus chemotherapy significantly improved progression-free survival compared with chemotherapy alone in patients with non-squamous non-small cell lung cancer (NSCLC), according to phase III data.
Patients with previously untreated stage IIIB or stage IV non-squamous NSCLC without EGFR or ALK translocations.
Patients were randomized 2:1 to receive tislelizumab 200 mg every three weeks combined with pemetrexed 500 mg/m2 and investigator’s choice of platinum chemotherapy or pemetrexed and platinum chemotherapy alone.
Tislelizumab-jsgr (Tevimbra) is approved for single-agent use in adult patients with unresectable or metastatic esophageal squamous cell carcinoma following prior systemic chemotherapy that did not include a PD-1/PD-L1 inhibitor.
Data from the phase 3 RATIONALE 302 study in which tislelizumab significantly improved overall survival (OS) vs chemotherapy at a median of 8.6 months vs 6.3 months, respectively.
The 6-month OS rate with tislelizumab was 62.3% vs 51.8% with chemotherapy; the respective 12-month OS rates were 37.4% and 23.7%.
Patients with advanced or metastatic ESCC who experienced disease progression during or after first-line systemic treatment were enrolled in the phase 3 study.
Participants (n = 512) were were randomly assigned in a 1:1 fashion to intravenous (IV) tislelizumab at 200 mg every 3 weeks or investigator’s choice of chemotherapy.
Those in the chemotherapy arm received one of the following regimens: 135 mg/m2 to 175 mg/m2 of IV paclitaxel given every 3 weeks or 80 mg/m2 to 100 mg/m2 given weekly; 75 mg/m2 of IV docetaxel given every 3 weeks; or IV irinotecan given at 125 mg/m2 on days 1 and 8 every 3 weeks.
In the subset of patients with a PD-L1 CPS of at least 10%, the median OS with tislelizumab was 10.3 months vs 6.8 months with chemotherapy.
Here, the 6-month OS rates in the tislelizumab and chemotherapy arms were 67.4% and 50.8%, respectively; the 12-month rates were 44.0% and 27.0%, respectively.
The median PFS reported with tislelizumab was 1.6 months vs 2.1 months with chemotherapy.
The 6-month PFS rates in these respective arms were 21.7% and 14.9%, and the respective 12-month PFS rates were 12.7% and 1.9%.
Tislelizumab also elicited a higher ORR than that experienced with chemotherapy, at 20.3% and 9.8%, respectively.
Moreover, the median DOR was longer with tislelizumab vs chemotherapy, at 7.1 months and 4.0 months, respectively.
The most common toxicities occurred in at least 20% of patients included increased glucose, decreased hemoglobin, decreased lymphocytes, decreased sodium, decreased albumin, increased alkaline phosphatase, anemia, fatigue, increased aspartate aminotransferase, musculoskeletal pain, decreased weight, increased alanine aminotransferase, and cough.
The addition of tislelizumab to chemotherapy led to a median overall survival (OS) of 17.2 months vs 10.6 months with placebo plus chemotherapy.
A phase 3 RATIONALE 305 study the median OS with tislelizumab plus chemotherapy was 15.0 months vs 12.9 months with placebo.