First-in-human dose-finding study of the ALK/EGFR inhibitor AP26113 in patients with advanced malignancies: Updated results.

Abstract

8031 Background: AP26113 is a novel tyrosine kinase inhibitor (TKI) that potently inhibits mutant activated forms of anaplastic lymphoma kinase (ALK+) and epidermal growth factor receptor (EGFRm), and TKI-resistant forms including L1196M (ALK) and T790M (EGFR). AP26113 does not inhibit native EGFR. Methods: The dose finding phase (3+3 design) of this phase I/II open-label, multicenter study is ongoing in pts with advanced malignancies (except leukemia) refractory to available therapies or for whom no standard treatment exists. Initial dosing is orally once daily. Results: As of 14 Jan 2013, 44 pts were enrolled: 30 mg n=3, 60 mg n=3, 90 mg n=8, 120 mg n=8, 180 mg n=11, 240 mg n=9, 300 mg n=2; 64% female, median age 60 yrs; diagnoses: non-small cell lung cancer (NSCLC, n=37), other (n=7). 26 pts discontinued: 18 disease progression, 6 adverse event (AE), 2 deaths (sudden death, hypoxia; both possibly related). Most common AEs: nausea (45%), fatigue (39%), diarrhea (27%); most common grade 3/4 treatment-related AE: diarrhea (5%). 2 dose limiting toxicities observed: grade 3 ALT increase, 240 mg; grade 4 dyspnea, 300 mg. Doses <300 mg are being explored further. 21 pts had ALK+ history (18 NSCLC, 3 other). Among 18 evaluable ALK+ pts, 10 responded. 15 ALK+ pts had 0 (n=3) or 1 (n=12) prior ALK TKI (crizotinib); of these, 2/3 and 8/12 pts (67%) responded, including 2 complete responses. The longest response is 40 wks (ongoing). 4 of 5 ALK+ pts with untreated or progressing CNS lesions at baseline and with follow-up scans had evidence of radiographic improvement in CNS, including 1 pt resistant to crizotinib and LDK378 (overall response = stable disease). 16 pts had EGFRm history (15 NSCLC, 1 SCLC); 14 pts had ≥1 prior EGFR TKI. Of 12 EGFRm pts with a follow-up scan, 1 pt (prior erlotinib) responded at 120 mg (duration 21 wks, ongoing), 6 pts had stable disease (2 ongoing, duration 7-31 wks). Conclusions: AP26113 has promising anti-tumor activity in ALK+ pts, with initial evidence of activity in EGFRm pts, and is generally well tolerated. Phase II will begin after the recommended phase II dose is determined, with 4 cohorts: crizotinib-naïve NSCLC; crizotinib-resistant NSCLC; EGFR TKI-resistant NSCLC; other tumors. NCT01449461. Clinical trial information: NCT01449461.