Bosutinib in Japanese patients with newly diagnosed chronic-phase chronic myeloid leukemia: final 3-year follow-up results of a phase 2 study.

Bosutinib has been evaluated for treatment of chronic-phase chronic myeloid leukemia (CP-CML) in several clinical studies, including in Japan. This open-label, single-arm, phase 2 study evaluated the efficacy and safety of bosutinib at a starting dose of 400 mg once daily in Japanese patients (n = 60) with newly diagnosed CP-CML. The minimum follow-up period was 3 years and median duration of treatment was 35.9 months. At study completion, 60% of patients were still on treatment. Cumulative rates of major molecular response (MMR), molecular response4 (MR4), and MR4.5 at any time were 70.0%, 53.3%, and 48.3%, respectively. No patient who achieved MMR or MR4 had a confirmed loss of response. No patient experienced on-treatment transformation to accelerated/blast phase or died within 28 days of the last bosutinib dose. Any-grade treatment-emergent adverse events (TEAEs) occurred in 100% (grade ≥ 3: 81.7%) of patients. The most common TEAEs were diarrhea (86.7%), increased alanine aminotransferase (55.0%), and increased aspartate aminotransferase (46.7%). No new safety signals emerged during the follow-up period. Bosutinib continues to demonstrate a favorable benefit/risk profile and is an important treatment option for Japanese patients with newly diagnosed CP-CML. Optimal management of TEAEs during initial treatment with bosutinib should be prioritized.Trial Registration: ClinicalTrials.gov ID: NCT03128411.

Safety profile of bosutinib in Japanese versus non-Japanese patients with chronic myeloid leukemia: a pooled analysis.

Bosutinib has been investigated in multiple clinical trials globally, including Japan, for treatment of chronic myeloid leukemia (CML). A pooled analysis of seven Pfizer-sponsored clinical trials evaluated the safety of bosutinib in Japanese (n = 138) vs non-Japanese (n = 1210) patients with CML. First-line bosutinib was administered in 54.3% vs 41.4% of patients, and second-line or later bosutinib in the remainder. Median treatment duration was 1.4 vs 2.3 years, and median relative dose intensity 78.1% vs 90.0%. Any-grade treatment-emergent adverse events (TEAEs) occurred in 100.0% vs 98.9% (grade ≥ 3: 81.9% vs 75.2%). In both groups, the most common TEAEs relevant to bosutinib were gastrointestinal (92.8% vs 84.7%), liver function (72.5% vs 34.8%), rash (63.8% vs 37.4%), and myelosuppression (55.1% vs 50.7%). TEAEs led to dose reduction in 65.2% vs 50.6%, dose interruption in 78.3% vs 68.8%, and permanent treatment discontinuation in 30.4% vs 25.4% of patients. The safety profile of bosutinib in Japanese patients was generally consistent with that in non-Japanese patients, despite a higher incidence of gastrointestinal, liver function, and rash events. TEAEs were largely manageable with dose modifications and supportive care in both groups. These data may help optimize TEAE management and outcomes in Japanese patients receiving bosutinib for CML. Trial registration ClinicalTrials.gov: NCT02130557, NCT03128411, NCT00574873, NCT00261846, NCT01903733, NCT00811070, NCT02228382.

Phase 2 study of bosutinib in Japanese patients with newly diagnosed chronic phase chronic myeloid leukemia.

This open-label, single-arm, phase 2 study (ClinicalTrials.gov, NCT03128411) evaluated the efficacy, safety, and pharmacokinetics of bosutinib at a starting dose of 400 mg once daily (QD) in Japanese patients with newly diagnosed chronic phase chronic myeloid leukemia (CP CML). The primary endpoint was major molecular response (MMR) at Month 12 in the modified as-treated population (Philadelphia chromosome-positive [Ph+] patients with e13a2/e14a2 transcripts). Sixty Japanese patients with CP CML were treated with bosutinib; median age was 55 years (range 20-83), 60.0% were males, and all were Ph+ and had e13a2/e14a2 transcripts. After median follow-up of 16.6 months (range 11.1-21.9), 41 (68.3%) patients remained on bosutinib. The MMR rate at Month 12 was 55.0% (2-sided 90% confidence interval: 44.4-65.6). There were no on-treatment transformations to accelerated/blast phase, and no patient died on treatment or within 28 days of the last bosutinib dose. The most common treatment-emergent adverse events were diarrhea (86.7%), increased alanine aminotransferase (55.0%), and increased aspartate aminotransferase (46.7%). The primary objective of this phase 2 study was met, and there were no new safety signals for bosutinib. These data suggest bosutinib is an effective first-line treatment option for Japanese patients with newly diagnosed CP CML.

Development of a Sustainable Release System for a Ranibizumab Biosimilar Using Poly(lactic-co-glycolic acid) Biodegradable Polymer-Based Microparticles as a Platform.

Ranibizumab is a humanized monoclonal antibody fragment against vascular endothelial growth factor (VEGF)-A and is widely used to treat age-related macular degeneration (AMD) caused by angiogenesis. Ranibizumab has a short half-life in the eye due to its low molecular weight and susceptibility to proteolysis. Monthly intravitreal injection of a large amount of ranibizumab formulation is a burden for both patients and medical staff. We therefore sought to develop a sustainable release system for treating the eye with ranibizumab using a drug carrier. A ranibizumab biosimilar (RB) was incorporated into microparticles of poly(lactic-co-glycolic acid) (PLGA) biodegradable polymer. Ranibizumab was sustainably released from PLGA microparticles (80+% after 3 weeks). Assay of tube formation by endothelial cells indicated that RB released from PLGA microparticles inhibited VEGF-induced tube formation and this tendency was confirmed by a cell proliferation assay. These results indicate that RB-loaded PLGA microparticles are useful for sustainable RB release and suggest the utility of intraocular sustainable release systems for delivering RB site-specifically to AMD patients.