Irinotecan Hydrochloride Lioposome (Heng Rui)

This phase 1b study aimed to evaluate the dose-limiting toxicity (DLT), maximum tolerated dose (MTD), pharmacokinetics, and preliminary efficacy of HR070803, a novel nanoliposomal formulation of irinotecan, in combination with 5-fluorouracil and leucovorin in patients with pretreated advanced solid tumors. This study consisted of dose-escalation and expansion stages. Dose escalation was performed with a traditional 3 + 3 design; patients received intravenous infusion of HR070803 from 60 to 80 mg/m2, followed by leucovorin (200 mg/m2) and 5-fluorouracil (2000 mg/m2) every 2 weeks. In the expansion stage, patients received treatments at selected tolerable dose. Fifteen patients received treatments at 60 mg/m2 (n = 12) and 80 mg/m2 (n = 3). DLTs occurred in 2 patients at 80 mg/m2 (grade 2 neutropenia that resulted in a dose delay of ≥ 7 days, n = 1; grade 3 febrile neutropenia, n = 1). The MTD was determined to be 60 mg/m2. The most frequent HR070803related adverse events included anorexia, leukopenia, neutropenia, nausea, fatigue, and diarrhea. SN-38, the active metabolite of irinotecan, exhibited lower maximum plasma concentrations and a prolonged terminal half-life when irinotecan was administered via nanoliposome compared to conventional injection. Overall, 4 patients achieved a partial response (confirmed, n = 2), and 9 had stable disease. The MTD of HR070803 was 60 mg/m2 when infused with 5-fluorouracil and leucovorin. Nanoliposomal encapsulation modified the pharmacokinetics of irinotecan and SN-38. HR070803 with 5-fluorouracil and leucovorin demonstrated a manageable safety profile and promising antitumor efficacy in advanced solid tumors.

Clinicaltrials.gov, NCT05086848. Retrospectively registered on Oct. 12, 2021.

Liposomal irinotecan has shown promising antitumor activity in patients with advanced or metastatic pancreatic ductal adenocarcinoma (PDAC) who have undergone prior gemcitabine-based therapies. This randomized, double-blind, parallel-controlled, multicenter phase 3 study (NCT05074589) assessed the efficacy and safety of liposomal irinotecan HR070803 combined with 5-fluorouracil (5-FU) and leucovorin (LV) in this patient population. Patients with unresectable, locally advanced, or metastatic PDAC who had previously received gemcitabine-based therapies were randomized 1:1 to receive either HR070803 (60 mg/m2 anhydrous irinotecan hydrochloride, equal to 56.5 mg/m2 free base) or placebo, both in combination with 5-FU (2000 mg/m2) and LV (200 mg/m2), all given intravenously every two weeks. The primary endpoint of the study was overall survival (OS). A total of 298 patients were enrolled and received HR070803 plus 5-FU/LV (HR070803 group, n = 149) or placebo plus 5-FU/LV (placebo group, n = 149). Median OS was significantly improved in the HR070803 group compared to the placebo group (7.4 months [95% CI 6.1–8.4] versus 5.0 months [95% CI 4.3–6.0]; HR 0.63 [95% CI 0.48–0.84]; two-sided p = 0.0019). The most common grade ≥ 3 adverse events in the HR070803 group were increased gamma-glutamyltransferase (19.0% versus 11.6% in placebo group) and decreased neutrophil count (12.9% versus 0 in placebo group). No treatment-related deaths occurred in the HR070803 group, while the placebo group reported one treatment-related death (abdominal infection). HR070803 in combination with 5-FU/LV has shown promising efficacy and manageable safety in advanced or metastatic PDAC in the second-line setting, representing a potential option in this patient population.