Sonidegib in the Treatment of Locally Advanced Basal Cell Carcinoma: a Retrospective Study

Multicenter Retrospective Andalusian Study of the Use of Sonidegib for the Treatment of Local Advanced Basal Cell Carcinoma in Real Clinical Practice

INTRODUCTION

Locally advanced basal cell carcinoma (LA-BCC) is defined as that BCC in which there is radiological confirmation of invasion of certain neighboring structures in depth and also, usually, a BCC that is of a sufficient size and invasion (although there is no radiological demonstration of deep invasion) in which surgery and radiotherapy are not adequate, are insufficient or are contraindicated to achieve the cure of the tumor, either due to characteristics of the tumor itself or of the patient. Sonidegib is indicated for the treatment of adult patients with locally advanced basal cell carcinoma that is not amenable to curative surgery or radiotherapy.

MATERIAL AND METHODS

This is a retrospective, multicenter and descriptive study in nine centers in Andalusia, Spain. Patients treated with sonidegib for >3 months for locally advanced BCC were included from 1 January 2021 to 1 January 2023. Epidemiological, efficacy and safety data were collected.

RESULTS

In the present study, a total of 38 patients were included, with a median age of 76.23 years (range 40-101). Prior treatment was surgery (31.57%; n = 25), radiotherapy (15.78%; n = 6), vismodegib (31.57%; n = 12). Eleven patients had not received prior treatment. LA-BCC were located in the cephalic pole, face or scalp. There was a total response in 9/38 patients (23.7%), partial response in 25/38 patients (65.8%) and no response in 4 patients (10.52%). In 6/34 patients, the dose was reduced to 200 mg every other day until it was discontinued due to adverse effects. The main adverse effects reported were dysgeusia (n = 8), asthenia (n = 8), = 6), muscle spasms (n = 6), alopecia (n = 4) and gastrointestinal intolerance (n = 4).

DISCUSSION

Sonidegib is the second iHh authorized for the treatment of adult patients with locally advanced BCC who are not amenable to curative surgery or radiotherapy, based on the results of the phase II clinical trial, BOLT. Sonidegib shows good effectiveness and an acceptable safety profile in routine clinical practice in the sample presented.

Efficacy and safety of sonidegib for the management of basal cell carcinoma: a drug safety evaluation

INTRODUCTION

Surgery is the standard management for most of basal cell carcinomas (BBCs). In some cases, also radiotherapy may be a valuable weapon as well as ablative and topical treatments. However, all these approaches may be limited by some tumor features. In this scenario, locally advanced BCCs (laBCC) and metastatic BCC, also defined as 'difficult-to-treat' BCC, remain the real treatment challenge. New knowledge on BCC pathogenesis, particularly the Hedgehog (HH) pathway, led to the development of new selective therapies such as vismodegib and sonidegib. In particular, sonidegib is an orally administered small molecules, which inhibits the HH signaling pathway through the binding to SMO receptor, recently approved for the management of adult patients with laBCC who are not amenable to curative surgery or radiation therapy.

AREAS COVERED

The purpose of this review is to analyze and discuss the efficacy and safety of sonidegib for the management of BCC, to provide a broad perspective on the currently available data.

EXPERT OPINION

Sonidegib is a valuable weapon for the management of difficult-to-treat BCC. Current data showed promising results in terms of effectiveness and safety. However, more studies are needed to underline its role in BCC management, also considering the presence of vismodegib, and to investigate its use in a long-term period.

Clinical Characteristics of an Italian Patient Population with Advanced BCC and Real-Life Evaluation of Hedgehog Pathway Inhibitor Safety and Effectiveness

BACKGROUND

Advanced basal cell carcinoma (aBCC) represents a complex and clinically heterogeneous group of lesions for which curative surgery and/or radiotherapy is unlikely. Systemic therapy with hedgehog pathway inhibitors (HHIs) changed the treatment landscape for this complex patient population.

OBJECTIVES

The aims of the present study are to describe the clinical characteristics of a real-life Italian cohort diagnosed with aBCC and to investigate effectiveness and safety of HHI.

METHODS

A multicenter observational study was performed by twelve Italian centers in the period January 1, 2016 - October 15, 2022. Patients aged ≥18 years and diagnosed with aBCC (locally advanced [laBCC] and metastatic BCC [mBCC]) were eligible for the study. Methods for investigating tumor response to HHI included clinical and dermatoscopic evaluation, radiological imaging, and histopathology. For HHI safety assessment, therapy-related adverse events (AEs) were reported and graded according to the Common Terminology Criteria for Adverse Events (CTCAE) version 5.0.

RESULTS

We enrolled 178 patients under treatment with HHI: 126 (70.8%) and 52 patients (29.2%) received sonidegib and vismodegib, respectively. Comprehensive data on HHI effectiveness and disease outcome were available for 132 (74.1%) of 178 patients: 129 patients had a diagnosis of laBCC (n = 84, sonidegib; n = 45, vismodegib) and 3 patients of mBCC (n = 2, vismodegib; n = 1, sonidegib, off-label). Objective response rate was 76.7% (95% confidence interval [CI]: 82.3-68.7) and 33.3% (95% CI: 88.2-1.7) for laBCC (complete response [CR]: 43/129; PR: 56/129) and mBCC (CR: 0/3; PR: 1/3), respectively. High-risk aBCC histopathological subtypes and occurrence of >2 therapy-related AEs were significantly associated with nonresponse to HHI therapy ([OR: 2.61; 95% CI: 1.09-6.05; p: 0.03] and [OR: 2.74; 95% CI: 1.03-7.9; p: 0.04]), respectively. Majority of our cohort (54.5%) developed at least 1 therapy-related AE, most of which were mild-moderate in severity.

CONCLUSIONS

Our results demonstrate the effectiveness and safety profile of HHI and confirm the reproducibility of pivotal trial results in real-life clinical setting.

The role of Hedgehog and Notch signaling pathway in cancer

Notch and Hedgehog signaling are involved in cancer biology and pathology, including the maintenance of tumor cell proliferation, cancer stem-like cells, and the tumor microenvironment. Given the complexity of Notch signaling in tumors, its role as both a tumor promoter and suppressor, and the crosstalk between pathways, the goal of developing clinically safe, effective, tumor-specific Notch-targeted drugs has remained intractable. Drugs developed against the Hedgehog signaling pathway have affirmed definitive therapeutic effects in basal cell carcinoma; however, in some contexts, the challenges of tumor resistance and recurrence leap to the forefront. The efficacy is very limited for other tumor types. In recent years, we have witnessed an exponential increase in the investigation and recognition of the critical roles of the Notch and Hedgehog signaling pathways in cancers, and the crosstalk between these pathways has vast space and value to explore. A series of clinical trials targeting signaling have been launched continually. In this review, we introduce current advances in the understanding of Notch and Hedgehog signaling and the crosstalk between pathways in specific tumor cell populations and microenvironments. Moreover, we also discuss the potential of targeting Notch and Hedgehog for cancer therapy, intending to promote the leap from bench to bedside.