Vismodegib: a review

Dynamic optical coherence tomography evaluation in locally advanced basal cell carcinoma during sonidegib treatment

BACKGROUND

Basal cell carcinoma (BCC) is the most common cancer in the Caucasian population. It has a multifactorial pathogenesis, in which constitutive activation of the Sonic Hedgehog signalling (SHH) pathway (via mutations in PTCH1 or SMO genes) represents by far the most common genetic aberration. The introduction of vismodegib and sonidegib, two SHH pathway inhibitors, changed the therapeutic approach of locally advanced and metastatic BCCs. EADO's (European Association of Dermato-Oncology) new staging system refers to these as 'difficult-to-treat' BCCs.

OBJECTIVE

The aim was to evaluate sonidegib's effectiveness in patients affected by difficult-to-treat BCCs by using non-invasive diagnostic techniques.

METHODS

We retrospectively evaluated 14 patients (4 females, 10 males; mean age 77 ± 11 years) affected by difficult-to-treat BCCs treated with oral sonidegib 200 mg/day that were followed with total body videodermoscopy (V-Track, Vidix 4.0) and dynamic optical coherence tomography (D-OCT, VivoSight Dx) since May 2022. Considering the risk of rhabdomyolysis routine blood tests, especially for creatine kinase concentrations, were performed. All treated patients were inserted in the BasoCare database, which aims to offer support to patients taking sonidegib. Complete and partial responses were evaluated by the overall reduction of the number of lesions and their individual sizes. Safety was evaluated by assessing the occurrence and severity of adverse reactions.

RESULTS

Eighty per cent achieved complete clearance and 75% reduction of diameter. D-OCT scans performed at every follow-up showed concordance with clinical appearance and demonstrated reduction of hyporeflective structures, that is, islets of tumour cells and overall improvement of morphology.

CONCLUSION

Sonidegib can be considered an effective treatment option in cases where surgery or radiotherapy would be unfeasible or has previously failed, although pigmented lesions did not show complete clearance, suggesting that there are factors other than the SHH pathway involved in tumour growth. Videodermoscopy and D-OCT were useful in the quick and seamless follow-up of lesions and added valuable information in assessing efficacy.

An update on the current and emerging pharmacotherapies for basal cell carcinomas

INTRODUCTION

Despite surgical approach is still the mainstay for basal cell carcinoma (BCC) management, several issues may limit the use of this technique, leading to the need for new treatments to offer patients a personalized approach.

AREAS COVERED

A comprehensive review of the available and emerging pharmacologic strategies for BCC management, including mechanisms of action, and potential adverse effects, has been performed to provide with an up-to-date manuscript on the current treatment scenario of BCC. Globally, targeting the Sonic-Hedgehog pathway is one of the main mechanisms of action of currently investigated drugs. Other alternatives are based on the concept of an enhancement of the immune response such as immune checkpoint inhibitors, or intra-tumor treatments.

EXPERT OPINION

Although low-risk BCCs are often treated with destructive methods or topical treatments, surgery is the mainstay of treatment for the majority of BCCs. However, several factors may limit the use of surgery in BCC management. Recently, major knowledge on BCCs pathogenesis has led to the development of effective and selective drugs. In our opinion, soon many drugs will be licensed, allowing clinicians to offer patients with BCC the right treatment at the right moment. Certainly, further studies are needed.

Glasdegib in combination with cytarabine and daunorubicin in patients with AML or high-risk MDS: Phase 2 study results

Glasdegib is a Hedgehog pathway inhibitor. This ongoing, open‐label, phase 2 study (NCT01546038) evaluated glasdegib plus cytarabine/daunorubicin in patients with untreated acute myeloid leukemia (AML) or high‐risk myelodysplastic syndromes (MDS). Patients received glasdegib 100 mg orally, once daily in continuous 28‐day cycles from day −3, with intravenous cytarabine 100 mg/m² on days 1‐7 and daunorubicin 60 mg/m² on days 1‐3. Patients in remission then received consolidation therapy (2‐4 cycles of cytarabine 1 g/m² twice daily on days 1, 3, 5 of each cycle), followed by maintenance glasdegib (maximum 6 cycles). Primary endpoint was complete remission (CR) in patients aged ≥55 years. Secondary endpoints included overall survival (OS), safety and outcome by mutational status. Patients had a median (range) age of 64.0 (27‐75) years, 60.0% were male, and 84.5% were white. In 69 evaluable patients, 46.4% (80% confidence interval [CI]: 38.7‐54.1) achieved investigator‐reported CR. Among patients ≥55 years old (n = 60), 40.0% (80% CI 31.9‐48.1) achieved CR. Among all 69 patients, median OS was 14.9 (80% CI 13.4‐19.3) months, with 12‐month survival probability 66.6% (80% CI 58.5‐73.4). The most common treatment‐related adverse events (≥50% patients) were diarrhea and nausea. There were no significant associations between mutational status (12 genes) and clinical response, suggesting potential benefit across diverse molecular profiles. Glasdegib plus cytarabine/daunorubicin was well tolerated and associated with clinical activity in patients with untreated AML or high‐risk MDS. A randomized phase 3 trial of glasdegib in combination with chemotherapy (7 + 3 schedule) is ongoing.

Experience With Vismodegib in the Treatment of Advanced Basal Cell Carcinoma at a Cancer Center

INTRODUCTION AND OBJECTIVES

Vismodegib is the first selective Hedgehog inhibitor approved for the treatment of locally advanced and metastatic basal cell carcinoma (BCC). In this article, we describe our experience with the use of this drug to treat advanced and/or multiple BCCs at a cancer center over 5 years.

MATERIAL AND METHODS

We analyzed the following variables: patient age and sex; tumor location, size, type, and characteristics; time since onset; primary or recurrent status; duration of treatment; response to treatment (complete, partial, stabilization, or absence of response); adverse effects; and recurrences.

RESULTS

We treated 22 patients, of whom 20 had locally advanced BCCs and 2 had metastatic BCCs with lymph node involvement. The treatment was administered over a mean of 11.8 months. Nine patients (41%) achieved complete response and 10 (45%) partial response. The disease was stabilized in 3 (14%). Two patients relapsed after a median of 21 months. The main adverse effects were dysgeusia, alopecia, and muscle cramps, all of which were mild. None of the patients developed squamous cell carcinoma in an area treated with vismodegib, although metatypical changes were observed after treatment.

CONCLUSIONS

With a response rate of 96%, vismodegib is a safe and effective treatment for locally advanced BCC. Adverse effects are generally mild but they need to be taken into account owing to their high frequency.

Merkel Cell Carcinoma with a Suppressor of Fused (SUFU) Mutation: Case Report and Potential Therapeutic Implications

Introduction

Merkel cell carcinoma is a neuroendocrine malignancy. Suppressor of fused (SUFU) is a tumor suppressor oncogene that participates in the Hedgehog (Hh) signaling pathway. The aim of the study was to describe a patient whose Merkel cell carcinoma demonstrated a SUFU genomic alteration.

Case Study

The Hh signaling pathway is involved in the pathogenesis of several tumors, including nevoid basal cell carcinoma syndrome that is associated with an alteration of the patched-1 (PTCH1) gene. Targeted molecular therapy against smoothened (SMO) with vismodegib has been shown to be an effective therapeutic intervention for patients with PTCH-1 mutation. The reported patient was presented with metastatic Merkel cell carcinoma. Analysis of his tumor, using a next-generation sequencing-based assay, demonstrated a genomic aberration of SUFU protein, a component of the Hh signaling pathway that acts downstream to SMO and, therefore, is unlikely to be responsive to vismodegib. Of interest, arsenic trioxide or bromo and extra C-terminal inhibitors impact signals downstream to SUFU, making this aberration conceivably druggable. His tumor has initially been managed with chemotherapy (carboplatin and etoposide) and subsequent radiation therapy is planned.

Conclusion

The pathogenesis of Merkel cell carcinoma is multifactorial, and related to ultraviolet radiation exposure, immunosuppression, and Merkel cell polyomavirus. We report a patient with a mutation in SUFU, a potentially actionable component of the Hh signaling pathway.

Electronic supplementary material

The online version of this article (doi:10.1007/s13555-015-0074-5) contains supplementary material, which is available to authorized users.