Efficacy and safety of bosutinib in patients treated with prior imatinib and/or dasatinib and/or nilotinib: Subgroup analyses from the phase 4 BYOND study.

The BYOND study evaluated the efficacy and safety of bosutinib 500 mg once daily in patients with chronic myeloid leukemia (CML) resistant/intolerant to prior tyrosine kinase inhibitors (TKIs). These post-hoc analyses assessed the efficacy and safety of bosutinib by resistance or intolerance to prior TKIs (imatinib-resistant vs dasatinib/nilotinib-resistant vs TKI-intolerant), and cross-intolerance between bosutinib and prior TKIs (imatinib, dasatinib, nilotinib), in patients with Philadelphia chromosome-positive chronic phase CML. Data are reported after ≥3 years' follow-up. Of 156 patients with Philadelphia chromosome-positive chronic phase CML, 53 were imatinib-resistant, 29 dasatinib/nilotinib-resistant, and 74 intolerant to all prior TKIs; cumulative complete cytogenetic response rates at any time were 83.7%, 61.5%, and 86.8%, and cumulative major molecular response rates at any time were 72.9%, 40.7%, and 82.4%, respectively. Of 141, 95, and 79 patients who received prior imatinib, dasatinib, and nilotinib, 64 (45.4%), 71 (74.7%), and 60 (75.9%) discontinued the respective TKI due to intolerance; of these, 2 (3.1%), 5 (7.0%), and 0 had cross-intolerance with bosutinib. The response rates observed in TKI-resistant and TKI-intolerant patients, and low cross-intolerance between bosutinib and prior TKIs, further support bosutinib use for patients with Philadelphia chromosome-positive chronic phase CML resistant/intolerant to prior TKIs. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02228382.

A Survey of Patient Experience in CML: American and Canadian Perspectives.

Purpose: With treatment, chronic myeloid leukemia (CML) has a favorable prognosis, however, individuals with CML experience impairment to their quality of life (QoL). The aim of this study was to examine the perspectives and experiences of individuals with CML and to understand their challenges communicating with their CML physician. Patients and Methods: An online survey in adults with CML (n=100) in the US and Canada assessed QoL, patient-provider relationships, treatment satisfaction, and understanding of CML and treatment goals via the MD Anderson Symptom Inventory, the Cancer Therapy Satisfaction Questionnaire and de novo survey questions. Participants were recruited via an external patient recruiter and CML Patient Groups. Results: Many participants reported hardships due to CML and its treatment. The main impacts were on the ability to work (21%), engage in personal activities (e.g., hobbies, 28%), and to enjoy sexual relations (median=2.00, IQR=8.50). A substantial proportion (21-39%) wished to discuss additional topics with their providers (e.g., management of CML and/or its impacts). While participants reported satisfaction with therapy overall (median=85.71, IQR=17.86), they indicated low to moderate treatment satisfaction with specific components, including concerns regarding side effects (median=43.75, IQR=43.75). Participants generally had a good understanding of CML (97%) and its treatment goals (92%). Conclusion: These findings advance our understanding of issues that need improvement to support QoL for individuals living with CML. Future work is needed to improve patient-provider relationships, address treatment-related side effects, and provide clinical information that is easier for patients to understand.

Negative control of apoptosis signal-regulating kinase 1 through phosphorylation of Ser-1034.

Apoptosis signal-regulating kinase 1 (ASK1) is a serine/threonine kinase that mediates cell stress signaling initiated by diverse stimuli, such as H(2)O(2) and TNF alpha. Owing to its critical role in promoting apoptosis, ASK1 activity is highly controlled in cells. Phosphorylation of ASK1 at Thr-845 has been correlated with its activation, while phosphorylation at Ser-967 negatively controls its death promoting activity. Here, we report the identification of a novel phosphorylation site at Ser-1034 in the C-terminal regulatory domain of ASK1. Mutating Ser-1034 to an unphosphorylatable Ala led to increased catalytic activity of ASK1 and enhanced proapoptotic function of ASK1. Thus, the proapoptotic function of ASK1 is suppressed in part by phosphorylation at its C-terminal regulatory domain, which may couple upstream survival kinases to the death regulatory machinery.