Lao, Christopher D.

CRA9003 The full, final text of this abstract will be available at abstract.asco.org at 7:30 AM (EDT) on Saturday, June, 1, 2013, and in the Annual Meeting Proceedings online supplement to the June 20, 2013, issue of Journal of Clinical Oncology. Onsite at the Meeting, this abstract will be printed in the Saturday edition of ASCO Daily News.

9037 Background: Therapies for aBCC, which includes metastatic (m) and locally advanced (la) BCC, are limited. Abnormal Hedgehog pathway signaling is a key driver in BCC pathogenesis. Primary analysis of the pivotal ERIVANCE BCC trial of vismodegib, an oral hedgehog pathway inhibitor (HPI), demonstrated an objective response rate (ORR) of 30% and 43%, in mBCC and laBCC patients, respectively, with a median duration of response (DOR) of 7.6 months. We present safety and investigator (INV) assessed efficacy results 18 months (29 May 2012) after primary analysis (26 Nov 2010). Methods: Multicenter, international, nonrandomized study in patients (N=104) with radiographically measurable mBCC or laBCC (surgery inappropriate due to multiple recurrence, or substantial morbidity or deformity anticipated) receiving 150 mg oral vismodegib daily until disease progression or intolerable toxicity. Key secondary endpoints included INV-assessed ORR, progression-free survival (PFS), DOR, overall survival (OS), and safety. Results: At data cutoff, 21 patients continued to undergo protocol-specified assessments and 56 patients were in survival follow-up. The median dose intensity was comparable with primary analysis. ORR was 48.5%, mBCC; 60.3%, laBCC, comparable with primary analysis. However, median DOR improved (mBCC=14.7; laBCC=20.3 months). The median OS for mBCC was 30.9 months but not estimable in laBCC. Adverse events remained consistent, with muscle spasm, alopecia, dysgeusia, weight decrease, and fatigue most frequently reported. Eleven more deaths were reported in the update period after primary analysis; these occurred in survival follow-up and were not drug-related. Conclusions: Vismodegib is the first FDA-approved HPI; thus, long-term efficacy and safety data are particularly relevant. 18-month update data confirmed prolonged responses and consistent safety in vismodegib-treated aBCC patients. Clinical trial information: NCT00833417.

CRA9003 Background: Gq/11 mutations are early oncogenic events in UM resulting in MAPK pathway activation. We demonstrated decreased viability in UM cell lines harboring Gq/11 mut with sel, a small molecule inhibitor of MEK1/2 (Ambrosini, CCR 2012). Methods: We conducted a 16 center randomized phase II study of hyd-sulfate sel 75 mg BID vs TMZ 150 mg/m2 daily for 5 days in 28-day cycles (or DTIC 1000 mg/m2 q21 days) for patients (pts) with metastatic UM with a Q209 Gq/11 mut who have not received prior TMZ/DTIC. The primary endpoint was progression free survival (PFS). Secondary endpoints included overall survival (OS) and response rate (RR). Select pts underwent tumor biopsies at baseline and after 14 (+/- 3 days) of sel. Our statistical plan required ≥80 pts randomized and ≥68 events to detect a PFS hazard ratio of 0.6 (p=0.1). Randomization was stratified by mut (Gq vs G11), M stage and number of prior therapies (tx). Tumor assessment occurred every 4 weeks (wks) for 8 wks and then every 8 wks using RECIST 1.1. Pts receiving TMZ who progressed could receive sel (TMZ→sel). Results: 80 pts were randomized. Sel (n=39): median age 66 (range 32-86), 54% male, 54% G11 mut, median ECOG PS 0 (range 0-1), 97% M1c, median prior tx 0 (range 0-2). TMZ (n=41): median age 60 (range 34-81), 63% male, 58% G11 mut, median ECOG PS 0 (range 0-1), 93% M1c, median prior tx 0 (range 0-2). 11/39 (28%) pts on sel experienced grade (gr) 3 toxicity (tox) manageable with dose modification (5 CPK elevation, 3 LFT elevation, 1 rash, 1 lymphopenia, 1 edema). 1/41 (2%) pt on TMZ experienced gr 3 tox (neutropenia). No gr 4/5 tox occurred. 28 pts on sel underwent paired tumor biopsies with inhibition of pERK and cyclinD1 observed by Western blot at day 14. At interim analysis (9/25/12), 55 pts were evaluable with 45 progression events and 16 deaths. Sel (n=27): median PFS 16 wks (95% CI 8-30.9), RR 11%, median OS 11.8 months (95% CI 4.8-not reached). TMZ (n=28): median PFS 4 wks (95% CI 3.7-15), RR 0%, median OS 4.7 months (95% CI 4.3-14.3). TMZ→sel (n=25): median PFS 8.1 wks (95% CI 7-15), RR 0%. Conclusions: Sel is the first drug to ever show improved clinical activity in UM relative to TMZ. Sustained target inhibition is observed with sel. Final results will be presented. Clinical trial information: NCT01143402.