Patterns and Management of Selected Adverse Events of Adult Patients with Imatinib-Resistant or -Intolerant Chronic Myeloid Leukemia (CML) From the ENACT (Expanding Nilotinib Access in Clinical Trials) Study.

Nilotinib, a potent and highly selective BCR-ABL kinase inhibitor, is approved for the treatment of patients (pts) with Philadelphia chromosome-positive chronic myelogeneous leukemia (Ph+ CML) in chronic phase (CML-CP) or accelerated phase (CML-AP) who are resistant or intolerant to prior therapy, including imatinib. The ENACT study is a Phase IIIb, open-label, multicenter study that evaluated the efficacy and safety of nilotinib in adult pts with imatinib-resistant or intolerant CML in a clinical practice setting outside of a registration program. It is the largest single source of efficacy and safety information of any available tyrosine kinase inhibitor (TKI) in CML. Data from ENACT are used to characterize the patterns and management of adverse events (AEs) in nilotinib pts with imatinib-resistant or -intolerant CML-CP or -AP.

Pts received nilotinib 400 mg twice daily. Safety assessments included monitoring for all AEs and cardiac procedures. The first occurrence of the following AEs were selected on the basis of the following criteria: 1) the most frequently reported hematologic or biochemical laboratory abnormalities; or 2) identified by participating investigators as AEs of interest that may lead to study drug discontinuation: thrombocytopenia, neutropenia, hyperglycaemia, elevated lipase, elevated amylase, hyperbilirubinaemia, elevated alanine transaminase (ALT), and elevated aspartate transaminase (AST). There were no differences observed between the pattern of management between AEs suspected and regardless of study drug relationship as well as all grades vs. grade 3/4. For this reason this analysis covers management of grade 3/4 AEs suspected of study-drug relationship including duration and subsequent management. The following actions taken were reported by the treating physicians: study drug dose adjusted or temporarily interrupted, non-drug therapy given, no action taken, study drug permanently discontinued, concomitant medication taken or hospitalization/ prolonged hospitalization. More than one action was allowed to be selected.

The AEs experienced by 1,603 pts (1,422 CP and 181 AP) were generally identified during nilotinib treatment and lasted for short durations. The number of the grade 3 and 4 AEs in CP and AP, median time from start of treatment and median duration are reported in Table. For all included AEs, the overall most common action taken for the first occurrence was dose adjustment or temporary interruption with the exception of hyperglycaemia which was most often managed by treatment with concomitant medications (8/11 of hyperglycaemia AEs in CP and 1/2 in AP). In the majority of the biochemical abnormalities other than hyperglycaemia there was no additional action taken. 49/308 (16%) events of thrombocytopenia in CP pts (9 in AP) were managed by non-drug therapy. 31/204 (15%) events of neutropenia in CP pts were managed by concomitant medication (6/33 events in AP). Permanent discontinuation of study drug was infrequently observed (number of pts in CP; AP): thrombocytopenia (25; 7), neutropenia (15; 2), hyperglycaemia (1; 0), elevated lipase (3; 0), elevated amylase (0; no pts), hyperbilirubinaemia (2; 0), elevated ALT (3; 0), and elevated AST (1; 0).

Based on a large cohort of 1,603 nilotinib pts with CML-CP and CML-AP, nilotinib is well-tolerated. Most study drug-related grade 3/4 AEs could be managed by temporary treatment interruption or dose adjustment, such that permanent discontinuation of study drug due to AEs was infrequent. The only events requiring concomitant medication administration or non-drug therapy were thrombocytopenia, neutropenia, hyperglycaemia and hyperbilirubinaemia. The AE profile observed was predictable and similar to that seen in registration trial.

le Coutre:Novartis: Honoraria, Research Funding; BMS: Honoraria. Ceglarek:Novartis Pharmaceuticals: Honoraria. Turkina:Novartis Pharmaceuticals: Honoraria. Kim:Bristol Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis Pharma: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Wyeth: Research Funding. Shen:Novartis Pharmaceuticals: Honoraria. Smith:Novartis Pharmaceuticals: Honoraria. Rizzieri:Novartis Pharma: Honoraria, Research Funding, Speakers Bureau. Szczudlo:Novartis: Employment. Berton:Novartis Pharmaceuticals: Employment. Wang:Novartis Pharmaceuticals: Employment. Dial:Novartis Pharmaceuticals: Research Funding. Nicolini:Novartis Pharma: Consultancy, Honoraria, Research Funding, Speakers Bureau; Bristol Myers Squibb: Consultancy, Honoraria, Research Funding, Speakers Bureau; Chemgenex: Honoraria, Speakers Bureau.