Sonidegib, a novel smoothened inhibitor for the treatment of advanced basal cell carcinoma

Hung Q Doan,1 Sirunya Silapunt,1 Michael R Migden2,3 1Department of Dermatology, University of Texas, McGovern Medical School, 2Mohs Surgery Unit, Department of Dermatology, 3Department of Head and Neck Surgery, The University of Texas MD Anderson Cancer Center, Houston, TX, USA Abstract: Basal cell carcinoma (BCC) is the most common nonmelanoma skin cancer. If left untreated, BCCs can become locally aggressive or even metastasize. Currently available treatments include local destruction, surgery, and radiation. Systemic options for advanced disease are limited. The Hedgehog (Hh) pathway is aberrantly activated in a majority of BCCs and in other cancers. Hh pathway inhibitors are targeted agents that inhibit the aberrant activation of the Hh pathway, with smoothened being a targeted component. Sonidegib is a novel smoothened inhibitor that was recently approved by the US Food and Drug Administration. This review focuses on BCC pathogenesis and the clinical efficacy of sonidegib for the treatment of advanced BCC. Keywords: nonmelanoma skin cancer, Hedgehog pathway, clinical trial

Safety and efficacy of vismodegib in patients with basal cell carcinoma nevus syndrome: pooled analysis of two trials

BACKGROUND: Aberrant activation of the Hedgehog (Hh) pathway is a key driver in the pathogenesis of basal cell carcinomas (BCCs), including patients with BCC nevus syndrome (BCCNS). It is unclear whether BCCs arising in patients with BCCNS respond differently to vismodegib than in patients without BCCNS. We examined the best overall response rate (BORR) and adverse events (AEs) of vismodegib in patients with advanced BCC (aBCC) with and without BCCNS. METHODS: Patients were treated with vismodegib 150 mg/day in the ERIVANCE BCC trial (ClinicalTrials.gov number, NCT00833417) and the expanded access study (EAS; ClinicalTrials.gov number, NCT01160250). BCCNS diagnosis was based on medical history at the time of enrollment. Metastatic BCC response was evaluated using Response Evaluation Criteria In Solid Tumors, version 1.0 (RECIST v1.0) in both studies. Locally advanced BCC was evaluated by a novel composite end point in ERIVANCE BCC and by RECIST v1.0 in the EAS. Response assessments were performed every 8 weeks in ERIVANCE BCC and every 8–16 weeks in the EAS. Safety assessments (National Cancer Institute Common Terminology Criteria for Adverse Events, version 3.0) were performed monthly in both trials. Because of described differences in response assessment/schedule, patients with BCCNS were not pooled across trials. Analytic cohorts for BCCNS and sporadic aBCC were created within each trial for comparison using descriptive statistical methods. RESULTS: Forty-one patients with BCCNS were included in the study: 22 from ERIVANCE BCC and 19 from the EAS. Investigator-assessed BORR in BCCNS groups ranged from 31 to 81 % in patients with locally advanced BCC (n = 33) and was 50 % in patients with metastatic BCC (n = 6). These results were comparable with the non-BCCNS groups. Incidence and severity of AEs were also comparable between the BCCNS and non-BCCNS groups. Amenorrhea was observed in both patient cohorts and was reversible in two patients who discontinued treatment. CONCLUSION: Vismodegib demonstrated comparable efficacy and safety against aBCC in patients with and without BCCNS

Sonidegib and vismodegib in the treatment of patients with locally advanced basal cell carcinoma: a joint expert opinion

Sonidegib and vismodegib are hedgehog pathway inhibitors (HhIs) approved for the treatment of advanced basal cell carcinoma (BCC). Until recently, vismodegib was the only targeted treatment available for patients with locally advanced BCC (laBCC) in cases where surgery and radiotherapy are inappropriate. Sonidegib has recently been approved and now presents an alternative treatment option. The clinical differences between the two HhIs in patients with laBCC are unclear, as no head-to-head randomized controlled trials are or will be initiated. Moreover, there were important differences in the designs of their pivotal studies, BOLT (sonidegib) and ERIVANCE (vismodegib), and these differences complicate evidence-based analysis of their relative efficacy and safety profiles. In this paper, a group of clinical experts in the management of laBCC summarizes the clinical and pharmacological profiles of sonidegib and vismodegib based on published data and their own clinical experience. One key difference between the two pivotal studies was the criteria used to assess BCC severity. ERIVANCE (a single-arm phase II trial) used the conventional Response Evaluation Criteria in Solid Tumors (RECIST), while the more recent double-blind randomized BOLT trial used the stringent modified RECIST (mRECIST). A pre-planned analysis adjusted the outcomes from BOLT with RECIST-like criteria and this enabled the experts to discuss relative efficacy outcomes for the two treatments. Centrally reviewed objective response rate (ORR) for vismodegib was 47.6% (95% CI 35.5-60.6) at 21-month follow-up using RECIST. After adjusting with RECIST-like criteria, the ORR for sonidegib according to central review at 18-month follow-up was 60.6% (95% CI 47.8-72.4). Both treatments were associated with similar patterns of adverse events. Sonidegib and vismodegib share the same efficacy and tolerability profiles, but their pharmacokinetic profiles show several differences, such as volume of distribution and half-life. Further studies are needed to understand how these differences may impact clinical practice

Long-term safety and efficacy of vismodegib in patients with advanced basal cell carcinoma: Final update of the pivotal ERIVANCE BCC study

© 2017 The Author(s). Background: In the primary analysis of the ERIVANCE BCC trial, vismodegib, the first US Food and Drug Administration-approved Hedgehog pathway inhibitor, showed objective response rates (ORRs) by independent review facility (IRF) of 30% and 43% in metastatic basal cell carcinoma (mBCC) and locally advanced BCC (laBCC), respectively. ORRs by investigator review were 45% (mBCC) and 60% (laBCC). Herein, we present long-term safety and final investigator-assessed efficacy results in patients with mBCC or laBCC. Methods: One hundred four patients with measurable advanced BCC received oral vismodegib 150 mg once daily until disease progression or intolerable toxicity. The primary end point was IRF-assessed ORR. Secondary end points included ORR, duration of response (DOR), progression-free survival, overall survival (OS), and safety. Results: At data cutoff (39 months after completion of accrual), 8 patients were receiving the study drug (69 patients in survival follow-up). Investigator-assessed ORR was 48.5% in the mBCC group (all partial responses) and 60.3% in the laBCC group (20 patients had complete response and 18 patients had partial response). ORRs were comparable across patient subgroups, including aggressive histologic subtypes (eg, infiltrative BCC). Median DOR was 14.8 months (mBCC) and 26.2 months (laBCC). Median OS was 33.4 months in the mBCC cohort and not estimable in the laBCC cohort. Adverse events remained consistent with clinical experience. Thirty-three deaths (31.7%) were reported; none were related to vismodegib. Conclusions: This long-term update of the ERIVANCE BCC trial demonstrated durability of response, efficacy across patient subgroups, and manageable long-term safety of vismodegib in patients with advanced BCC. Trial registration: This study was registered prospectively with Clinicaltrials.gov , number NCT00833417on January 30, 2009