Pegfilgrastim biosimilar (Cinfa Biotech SL)

Polyethylene glycol (PEG) is a polymer covalently attached to proteins to improve their half‐life and efficacy. We previously reported that the PEGylated granulocyte colony‐stimulating factor (PEG‐G‐CSF) is immunogenic, which could adversely impact drug efficacy and safety in animal models. Here, we analyzed the relationship between anti‐PEG antibody titers and the clinical impact of PEG‐G‐CSF in 19 hematological patients. A gradual decrease of anti‐PEG antibody titers from baseline was observed after PEG‐G‐CSF administration. Of the 19 participants, 10 were assessed for noninfectious fever after the first administration of PEG‐G‐CSF and three experienced this reaction. The receiver operating characteristic curve revealed that the cut‐off values of pretreated anti‐PEG IgM and IgG titers for noninfectious fever were set at 5.0 and 96.6 U/mL, respectively. All patients who experienced noninfectious fever had anti‐PEG antibody titers above this cut‐off value (P = .033). An enzyme‐linked immunosorbent assay revealed that some anti‐PEG antibodies in patients with anti‐PEG antibody titers above the cut‐off value reacted with the PEGylated liposome. These results indicate the reactivity of the anti‐PEG antibodies to PEGylated therapeutics observed in hematologic patients and the possibility of the relationship between high titers of anti‐PEG antibodies and the development of adverse events after PEG‐G‐CSF administration.

In this open‐label, Phase 1 study, we explore the safety and efficacy of E7389‐LF (liposomal formulation of eribulin) in Japanese patients with advanced solid tumors.

This open‐label, Phase 1 study enrolled Japanese adult patients to receive E7389‐LF for the treatment of advanced solid tumors. Treatment with E7389‐LF 2.0 mg/m2 every 3 weeks (previously determined maximum tolerated dose) was tested for the treatment of adenoid cystic carcinoma, gastric cancer, esophageal cancer, or small lung cell cancer in the expansion part of this study. Secondary endpoints included safety, objective response rate, best overall response, and progression‐free survival.

As of October 16, 2020, 43 patients were enrolled (adenoid cystic carcinoma, n = 12; gastric cancer, n = 10; esophageal cancer, n = 11; small cell lung cancer, n = 10). Thirty‐three patients experienced a Grade ≥3 treatment‐related treatment‐emergent adverse event, most commonly neutropenia (53.5%). Additionally, the incidence of hypersensitivity did not appear to change with a reduced number of infusion steps (2 vs. 4) and patients who were administered prophylactic pegylated granulocyte‐colony stimulating factor had a noticeably lower incidence of Grade 3–4 neutropenia (although this did not have a proper control). The overall objective response rate was 11.6% (95% confidence interval: 3.9–25.1), corresponding to two partial responses in patients with adenoid cystic carcinoma, two partial responses in gastric cancer, and one partial response in esophageal cancer. Median progression‐free survival was longer in the adenoid cystic carcinoma population (16.6 months) than in others.

E7389‐LF 2.0 mg/m2 every 3 weeks was well tolerated for the treatment of several different tumor types, and larger studies in these populations are warranted.