Abstract

Background

Ponatinib is a potent oral pan–BCR-ABL tyrosine kinase inhibitor (TKI) with activity against native and mutant BCR-ABL. The efficacy and safety of ponatinib (45 mg once daily) in pts with CP-CML were evaluated in the phase 2 PACE trial.

Objectives

To review the management of treatment-related AEs (TRAEs) that emerged during therapy with ponatinib in the PACE trial.

Methods

A total of 270 CP-CML pts (267 in efficacy population) resistant or intolerant to dasatinib or nilotinib or with the T315I mutation were enrolled in this ongoing, phase 2, international, open-label clinical trial. The primary endpoint was major cytogenetic response (MCyR) at any time within 12 mos. Safety monitoring included collection of AEs, and the following variables were evaluated: incidence, severity, time to onset, duration, and management. Select TRAEs are discussed. Data as of 01 Apr 2013 are reported, with a median follow-up of 20 (0.1–28) mos. Minimum follow-up for pts remaining on study was 18 mos.

Results

Median age was 60 (18-94) yrs; median time from diagnosis to first dose was 7 (0.5-27) yrs; 93% had ≥2 prior TKIs, 60% ≥3. Ponatinib demonstrated significant activity in CP-CML pts: 56% MCyR, 46% CCyR, and 36% MMR. At the time of analysis, 60% of pts remained on study. The most frequent reasons for discontinuation were AEs (14%) and progression (8%).

The most common hematologic TRAE was thrombocytopenia (41% any grade, 32% grade 3/4). The incidence by time to initial onset is shown below (Figure). Pts experienced thrombocytopenia for a median total duration of 166 days (64% of whom had >1 event) and typically required dose modification: 13% drug withdrawn, 40% dose reduced, 29% dose interrupted only, 17% no dose modification. Among pts with thrombocytopenia, 27% required a platelet transfusion. Thirteen percent of CP-CML pts experienced treatment-related neutropenia and thrombocytopenia.

Figure.

Incidencea of Select TRAEs by Time to Initial Onset in CP-CML

Figure.

Incidencea of Select TRAEs by Time to Initial Onset in CP-CML

The most common nonhematologic TRAE was rash (39% any grade, 4% grade 3/4), which includes erythematous, macular, and papular rash. Pts experienced rash for a median total duration of 65 days (46% of whom had >1 event) and most did not require dose modification: 0% drug withdrawn, 15% dose reduced, 11% dose interrupted only, 73% no dose modification. One additional pt discontinued due to grade 2 treatment-related exfoliative rash.

Pancreatitis was observed (7% any grade, 6% grade 3/4). Median duration was 5 days. Pts were typically managed with dose modification: 5% drug withdrawn, 58% dose reduced, 32% dose interrupted only, 5% no dose modification.

Treatment-emergent cardiovascular events were observed in 8% of pts and treatment-emergent cerebrovascular or peripheral vascular events in 11%. Cardiovascular events were considered treatment-related in 4%; cerebrovascular or peripheral vascular events were also considered treatment-related in 4%. The median time to initial onset was 9 mos for cardiovascular and 11 mos for cerebrovascular or peripheral vascular events. The median duration was 6 and 97 days, respectively. Management of pts with cardiovascular AEs: 20% drug withdrawn, 10% dose reduced, 40% dose interrupted only, 30% no dose modification. Management of pts with cerebrovascular or peripheral vascular AEs: 8% drug withdrawn; 8% dose reduced; 17% dose interrupted only; 67% no dose modification.

Conclusions

Ponatinib has robust antileukemic activity in heavily pretreated CP-CML pts (93% of whom received ≥2 prior TKIs). Treatment-related thrombocytopenia and pancreatitis generally occurred early in therapy and were manageable with dose modification. Treatment-related rash generally occurred early in therapy, was mild-to-moderate in severity, managed without the need for dose modification, and rarely led to discontinuation. Management of treatment-related arterial thrombotic events varied; pts with predisposing cardiovascular risk factors should be monitored closely and managed accordingly. ClinicalTrials.gov ID: NCT01207440

aIncidence = (number of pts with initial onset during time interval) / (number of pts dosed during time interval [N] excluding those who previously experienced the event) X 100

Disclosures:

Le Coutre:Novartis: Research Funding; Novartis, BMS, Pfizer: Honoraria. Kim:BMS, Novartis, IL-Yang: Consultancy; BMS, Novartis, Pfizer, ARIAD, IL-Yang: Research Funding; BMS, Novartis, Pfizer, IL-Yang: Honoraria; BMS, Novartis, Pfizer: Speakers Bureau; BMS, Pfizer: Membership on an entity’s Board of Directors or advisory committees. Pinilla-Ibarz:Novartis, Ariad: Research Funding; Novartis, Ariad, BMS and Pfizer: Speakers Bureau. Paquette:Ariad, BMS, Novartis: Consultancy; Ariad, BMS, Novartis: Honoraria; Ariad, BMS, Novartis: Speakers Bureau. Chuah:Novartis, BMS: Honoraria. Nicolini:Novartis, ARIAD, Teva: Consultancy; Novartis, BMS: Research Funding; Novartis, BMS, Teva, Pfizer, ARIAD: Honoraria; Novartis, BMS, TEva: Speakers Bureau; Novartis, ARIAD, Teva, Pfizer: Membership on an entity’s Board of Directors or advisory committees. Apperley:Novartis: Research Funding; Ariad, Bristol Myers Squibb, Novartis, Pfizer, Teva: Honoraria. Talpaz:Ariad, BMS, Sanofi, INCYTE: Research Funding; Ariad, Novartis: Speakers Bureau; Ariad, Sanofi, Novartis: Membership on an entity’s Board of Directors or advisory committees. DeAngelo:Ariad, Novartis, BMS: Consultancy. Abruzzese:BMS, Novartis: Consultancy. Rea:BMS, Novartis, Pfizer, Ariad, Teva: Honoraria. Baccarani:ARIAD, Novartis, BMS: Consultancy; ARIAD, Novartis, BMS, Pfizer, Teva: Honoraria; ARIAD, Novartis, BMS, Pfizer, Teva: Speakers Bureau. Muller:Novartis, BMS, ARIAD: Consultancy; Novartis, BMS: Research Funding; Novartis, BMS, ARIAD: Honoraria. Gambacorti-Passerini:Pfizer: Research Funding; Pfizer, BMS: Honoraria. Lustgarten:ARIAD: employees of and own stock/stock options in ARIAD Pharmaceuticals, Inc Other, Employment. Yanase:ARIAD: employees of and own stock/stock options in ARIAD Pharmaceuticals, Inc. Other, Employment. Turner:ARIAD: Employment. Haluska:ARIAD: employees of and own stock/stock options in ARIAD Pharmaceuticals, Inc Other, Employment. Deininger:BMS, ARIAD, NOVARTIS: Consultancy; BMS, NOVARTIS, CELGENE, GILEAD: Research Funding; ARIAD, NOVARTIS: Advisory Boards, Advisory Boards Other. Hochhaus:Ariad, Novartis, BMS, MSD, Pfizer: Research Funding; Novartis, BMS, Pfizer: Honoraria. Hughes:Novartis, BMS, ARIAD: Honoraria, Research Funding. Goldman:ARIAD: Honoraria. Shah:Ariad, Bristol-Myers Squibb: Consultancy, Research Funding. Kantarjian:ARIAD, Novartis, BMS, Phizer: Research Funding. Cortes:Ariad, Pfizer, Teva: Consultancy; Ariad, BMS, Novartis, Pfizer, Teva: Research Funding.

Author notes

*

Asterisk with author names denotes non-ASH members.