Vismodegib in the treatment of basal cell carcinoma: indications for clinical practice

Development of a molecularly imprinted polymer-based electrochemical sensor with metal-organic frameworks for monitoring the antineoplastic drug vismodegib

A novel and robust electrochemical sensing tool for the determination of vismodegib (VIS), an anticancer drug, has been developed by integrating the selective recognition capabilities of molecularly imprinted polymer (MIP) and the sensitivity enhancement capability of metal-organic framework (MOF). Prior to this step, the electrochemical behavior of VIS was investigated using a bare glassy carbon electrode (GCE). It was observed that in 0.5 M H2SO4 solution as electrolyte, VIS has an oxidation peak around 1.3 V and the oxidation mechanism is diffusion controlled. The determination of VIS in a standard solution using a bare GCE showed a linear response in the concentration range from 2.5 μM to 100 μM, with a limit of detection (LOD) of 0.75 μM. Since sufficient sensitivity and selectivity could not be achieved with bare GCE, a MIP sensor was developed in the next step of the study. For this purpose, the GCE surface was first modified by drop casting with as-synthesized Co-MOF. Subsequently, a MIP network was synthesized via a thermal polymerization approach using 2-acrylamido-2-methylpropanesulfonic acid (AMPS) as monomer and VIS as template. MOFs are ideal electrode materials due to their controllable and diverse morphologies and modifiable surface properties. These characteristics enable the development of MIPs with more homogeneous binding sites and high affinity for target molecules. Integrating MOFs could help the performance of sensors with the desired stability and reproducibility. Electrochemical analysis revealed an observable enhancement of the output signal by the incorporation of MOF molecules, which is consistent with the sensitivity-enhancing role of MOF by providing more anchoring sites for the attachment of the polymer texture to the electrode surface. This MOF-MIP sensor exhibited impressive linear dynamic ranges ranging from 0.1 to 1.0 pM for VIS, with detection limits in the low picomolar range. In addition, the MOF-MIP sensor offers high accuracy, selectivity and precision for the determination of VIS, with no interference observed from complex media of serum samples. Additionally, in this study, Analytical GREEnness metric (AGREE), Analytical GREEnness preparation (AGREEprep) and Blue Applicability Grade Index (BAGI) were used to calculate the green profile score.

Hedgehog signaling in tissue homeostasis, cancers, and targeted therapies

The past decade has seen significant advances in our understanding of Hedgehog (HH) signaling pathway in various biological events. HH signaling pathway exerts its biological effects through a complex signaling cascade involved with primary cilium. HH signaling pathway has important functions in embryonic development and tissue homeostasis. It plays a central role in the regulation of the proliferation and differentiation of adult stem cells. Importantly, it has become increasingly clear that HH signaling pathway is associated with increased cancer prevalence, malignant progression, poor prognosis and even increased mortality. Understanding the integrative nature of HH signaling pathway has opened up the potential for new therapeutic targets for cancer. A variety of drugs have been developed, including small molecule inhibitors, natural compounds, and long non-coding RNA (LncRNA), some of which are approved for clinical use. This review outlines recent discoveries of HH signaling in tissue homeostasis and cancer and discusses how these advances are paving the way for the development of new biologically based therapies for cancer. Furthermore, we address status quo and limitations of targeted therapies of HH signaling pathway. Insights from this review will help readers understand the function of HH signaling in homeostasis and cancer, as well as opportunities and challenges of therapeutic targets for cancer.

Long-Term Management of Advanced Basal Cell Carcinoma: Current Challenges and Future Perspectives

Simple Summary

Local therapies are no longer an option for locally advanced basal cell carcinoma. Abnormal activation of the hedgehog signaling pathway leads to uncontrolled tumor growth. Hedgehog pathway inhibitors are an effective treatment option for this kind of tumor. However, treatment-related toxicity under long-term treatment may lead to limitations in quality of life, and thus to therapy interruption or even discontinuation. This review summarizes pertinent treatment adjustments and novel therapeutic strategies for effective treatment of locally advanced basal cell carcinoma.

Abstract

The first-line therapy for locally advanced basal cell carcinoma (laBCC) is Hedgehog pathway inhibitors (HHIs), as they achieve good efficacy and duration of response. However, toxicity in the course of long-term treatment may lead to a decrease in the quality of life, and consequently to interruption or even discontinuation of therapy. As HHI therapy is a balancing act between effectiveness, adverse events, quality of life, and adherence, numerous successful treatment strategies have evolved, such as dose reduction and dose interruptions with on-off treatment schedules or interruptions with re-challenge after progression. As a small percentage of patients show primary or acquired resistance to HHIs, the inhibition of programmed cell death protein 1 (PD-1) has been approved as a second-line therapy, which may also be accompanied by immune-related toxicities and non-response. Thus, optimization of current treatment schedules, novel agents, and combination strategies are urgently needed for laBCC. Here, we narratively model the treatment sequence for patients with laBCC and summarize the current state of approved treatment regimens and therapeutic strategies to optimize the long-term management of laBCC.

Basal Cell Carcinoma: Pathology, Current Clinical Treatment, and Potential Use of Lipid Nanoparticles

Skin cancer is the most common type of carcinoma diagnosed worldwide, with significant morbidity and mortality rates among Caucasians, in particular basal cell carcinoma (BCC). The main risk factors of BCC are well-identified, and there are many chemotherapeutic drugs available for its treatment. The effectiveness of therapeutic options is governed by several factors, including the location of the tumor, its size, and the presence of metastases (although rare for BCC). However, available treatments are based on non-targeted approaches, which encounter a significant risk of systemic toxicity in several organs. Site-specific chemotherapy for BCC has been proposed via the loading of anticancer drugs into nanoparticles. Among various types of nanoparticles, in this review, we focus on potential new regimens for the treatment of BCC using classical anticancer drugs loaded into novel lipid nanoparticles. To meet patient aesthetic expectations and enhance the effectiveness of basal cell carcinoma treatment, new therapeutic topical strategies are discussed, despite a limited number of reports available in the literature.

Tailored Toxicity-Driven Administration of Vismodegib in Patients With Multiple or Locally Advanced Basal Cell Carcinoma: A Pilot Analysis

In this pilot study, we describe our experience with vismodegib in the treatment of basal cell carcinoma (BCC) and evaluate the feasibility of a tailored toxicity-driven administration of vismodegib in patients with multiple or locally advanced BCC. We retrospectively analyzed the clinical charts of 17 consecutive patients with BCC who were treated with vismodegib. Therapy was started at the usual dosage of 150 mg per day per person, continuously; a rescheduled dosage of 150 mg per day for 4 weeks with a subsequent stop of 2 weeks was allowed during the treatment according to the standard practice of our institution. During treatment, 14 patients with responsive disease presented an adverse event (100% cramps and 20% dysgeusia), therefore, requiring a change in the treatment plan. Overall, in eight out of 17 patients (47% of the overall population), it was possible to re-schedule the treatment by postponing therapy for 2 weeks every 4 weeks. These patients were all still alive at the time of the present analysis and were showing complete response. Adverse events resolved during the first interruption of therapy. The intermittent vismodegib schedule assessed in this pilot series could be beneficial in improving duration of treatment, allowing to maintain a long-term treatment response, even in an elderly and fragile population. Based on these preliminary findings, dedicated studies may be planned to further evaluate an intermittent schedule of vismodegib administration.

A Practical Guide for the Follow-Up of Patients with Advanced Basal Cell Carcinoma During Treatment with Hedgehog Pathway Inhibitors

The Hedgehog pathway inhibitors (HPIs), vismodegib and sonidegib, are increasingly employed in the treatment of patients with advanced basal cell carcinoma (BCC). The aim of this review is to create a synthesis of available information in the literature regarding the follow-up of patients with advanced BCC treated with HPIs and to provide the treating physician with a structured practical guide to standardize clinical practice. Several challenges during treatment are addressed: to optimally evaluate tumor responses, to differentiate between resistance (HPI rechallenge not possible) and recurrence (HPI rechallenge may be possible) in case of BCC regrowth, to readily assess for toxicity and tolerability issues, to provide patients with practical ways and behaviors to effectively cope with adverse events, and to improve patient adherence and quality of life. IMPLICATIONS FOR PRACTICE: This is a practical guide for clinical practice regarding the monitoring and follow-up of patients with advanced basal cell carcinoma (BCC) during treatment with the Hedgehog pathway inhibitors (HPIs) vismodegib and sonidegib. This review aims to bridge the gap in knowledge of assessing tumor response for BCC with both an externally visible component and an infiltrating component measurable with imaging. Furthermore, it addresses the follow-up for adverse events as a challenging multistep process involving practices aiming to readily assess new-onset symptoms of HPI toxicity, perform total-body skin examination, and improve patient adherence and quality of life.

Managing adverse events associated with vismodegib in the treatment of basal cell carcinoma

Basal cell carcinomas are the most common form of skin cancer. Some develop into advanced cases not suitable for standard therapy. Vismodegib is the first-in-class oral hedgehog pathway inhibitor (which is dysregulated in 90% of basal cell carcinomas), and has demonstrated efficacy for advanced disease in clinical trials. An UK expert panel met to discuss management strategies for adverse events associated with vismodegib (most commonly taste disturbances, muscle cramps and alopecia). Managing patient expectations and implementing treatment breaks were considered important strategies. Quinine was useful to alleviate muscle cramps. For taste disturbances, food swaps alongside dietician referral were suggested. The experts concluded that these common adverse events can be successfully managed to allow optimum treatment duration of vismodegib.

Phase I, multicenter, open-label, dose-escalation study of sonidegib in Asian patients with advanced solid tumors

Sonidegib is a selective inhibitor of Smoothened receptor, which is a key regulator of the Hedgehog signaling pathway. The purpose of this study was to determine the maximum tolerated dose based on dose‐limiting toxicity (DLT) and the recommended dose (RD) of sonidegib in Asian patients with advanced solid tumors. This was an open‐label, single‐arm, multicenter, two‐group, parallel, dose‐escalation, phase I study undertaken in Asian patients; group 1 included patients from Japan and group 2 included patients from Hong Kong and Taiwan. Dose escalation was guided by a Bayesian logistic regression model dependent on DLTs in cycle 1 and other safety findings. A total of 45 adult Asian patients with confirmed advanced solid tumors were enrolled. Group 1 included 21 patients (12 treated with 400 mg q.d. [once daily] and 9 treated with 600 mg q.d.) and group 2 included 24 patients (12 treated with 400 mg q.d., 8 treated with 600 mg q.d., and 4 treated with 800 mg q.d.). Elevation in creatine kinase was the DLT in both groups. The most common adverse events suspected to be related to sonidegib in both patient groups were increase in creatine kinase levels, myalgia, fatigue, and abnormal hepatic function. The RD of 400 mg q.d. was defined in both groups. Difference in tolerability was noted between the East Asian patients and Western population. The RD in East Asian patients (400 mg q.d.) was lower than in patients from Europe and the USA (800 mg q.d. and 250 mg twice daily). (Registered with Clinicaltrials.gov: NCT01208831.)

Sonidegib showed a similar safety profile in East Asian patients as that of Western population. No new AEs were reported in the Asian population. The recommended dose of sonidegib in East Asian patients (400 mg) was lower than Western MTD (800 mg daily or 250 mg twice daily) suggesting a difference in tolerability between the 2 populations.