Clinical and direct immunofluorescence characteristics of cutaneous toxicity associated with enfortumab vedotin

Brigatinib can inhibit proliferation and induce apoptosis of human immortalized keratinocyte cells

Background

Brigatinib is approved in multiple countries for the treatment of patients with anaplastic lymphoma kinase (ALK)-positive non-small cell lung cancer (NSCLC). Despite its superior efficacy, the dermal toxicities caused by brigatinib cannot be overlooked. However, its underlying mechanism remains unknown.

Methods

The effects of brigatinib on the proliferation ability of human immortalized keratinocyte (HaCaT) cells were evaluated using Cell Counting Kit-8 (CCK-8) proliferation, colony formation, and 5-ethynyl-2'-deoxyuridine (EdU) incorporation assays. The effects of brigatinib on apoptosis were detected using Annexin FITC/PI and Acridine Orange (AO) staining assays. Cell cycle was assessed with flow cytometry. An analysis of transcriptome by RNA sequencing procedures (RNA-seq) was performed to reveal the key regulatory genes. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) were used to find out the biological function and related signal pathways. The expressions of amphiregulin, epiregulin and transforming growth factor alpha (TGFA) and the protein levels of Phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) and Cleaved-Caspase three were measured by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blot assay.

Results

Brigatinib inhibits cell proliferation with an IC50 value of 2.9 μmol/L and significantly increases apoptosis rates. Transcriptome sequencing (RNA-seq) indicates that brigatinib could significantly downregulate the expression of amphiregulin, epiregulin and TGFA. In addition, we demonstrated that brigatinib reduced the protein expression of amphiregulin, epiregulin, TGFA, PI3K, AKT and phosphorylated AKT (p-AKT).

Conclusion

This study confirms the inhibition of HaCaT cells growth and progression by brigatinib and highlights the potential value of the PI3K/AKT pathway as a therapeutic target for brigatinib-induced dermal toxicities.

Dermatologic toxicities of antibody-drug conjugates

Antibody-drug conjugates (ADCs) are a new and emerging category of oncologic treatments that combine the target specificity of a monoclonal antibody with a cytotoxic payload. These drugs are associated with unique cutaneous toxicities that vary across agents. Currently, there are eleven ADCs with regulatory approval for solid and liquid tumors and over 80 ADCs currently in clinical development, it is critical for dermatologists to recognize and appropriately mitigate the cutaneous toxicities associated with these therapies. This clinical review will summarize the novel mechanisms and indications of approved ADCs, discuss dermatologic toxicities demonstrated in clinical trials and postmarketing studies, and impart recognition and management guidance when encountering these reactions to help maintain patients safely and comfortably on their medications.

Enfortumab vedotin-induced cutaneous eruption: Ring mitotic figures as a distinctive histopathologic feature

Enfortumab vedotin (EV), a nectin-4-binding agent that affects microtubules, has become standard therapy for advanced urothelial carcinoma. The agent, now given in combination with pembrolizumab, frequently induces cutaneous reactions. Here, we report a severe EV-induced cutaneous eruption. A 58-year-old woman with metastatic urothelial carcinoma developed a rash after receiving simultaneous first doses of EV and pembrolizumab. The eruption began on the flank and spread to involve her trunk and extremities with prominent involvement of folds, including the axillae and medial thighs. Skin biopsy revealed extensive vacuolar alteration of the basal epidermis and numerous epidermal keratinocytic mitotic figures, often suprabasilar, including ring and "starburst" forms. The findings supported a diagnosis of EV-induced eruption. With EV cessation and systemic corticosteroids, the rash resolved over a few weeks. Pembrolizumab was restarted as monotherapy, and the patient's cancer showed a significant radiographic treatment response at 3 months. An emerging literature of small series and case reports, largely from oncologic literature, presents the histopathology of EV-induced cutaneous eruption as a vacuolar interface dermatitis with the inconsistently reported feature of arrested mitotic figures. This case study demonstrates distinctive clinical and histopathologic features of EV-induced eruption, which may inform dermatologic and oncologic management.

Nectin-4-directed antibody-drug conjugates (ADCs): Spotlight on preclinical and clinical evidence

Nectin-4 (Nectin cell adhesion molecule 4), a type I transmembrane cell adhesion protein, was demonstrated to be overexpressed in a variety of tumors, making it an attractive antigen for targeted therapies such as antibody-drug conjugates (ADCs). Of great note, the US Food and Drug Administration (FDA)-approval of the first Nectin-4-directed ADC, enfortumab vedotin (EV), in urothelial cancer (UC) not only introduced Nectin-4 as a clinically validated and reliable target antigen but also confirmed the evolving role of Nectin-4-directed ADCs as novel and promising cancer therapeutics. In addition to EV, there have been or are currently being seven and eleven Nectin-4-directed ADCs, respectively, in various stages of clinical trials and preclinical development, offering a promising future for the treatment of Nectin-4-positive cancer patients. This study reviewed clinical- and preclinical-stage Nectin-4-directed ADCs.

Enfortumab Vedotin Drug Eruption: Cutaneous Adverse Events and Histopathologic Findings

ABSTRACT

Enfortumab is a monoclonal antibody directed against nectin-4 and, when combined with vedotin, is an antibody-drug conjugate approved for the treatment of locally advanced or metastatic urothelial cancers. A 75-year-old woman with stage IV papillary urothelial carcinoma of the bladder who completed cycle 2 of enfortumab vedotin (EV) infusions presented to our dermatology department for new-onset symmetric and painful dusky erythematous patches on the extremities and trunk without mucosal involvement. Two biopsies were obtained, which revealed an interface dermatitis with notable ring mitoses within the basal and suprabasal layers of the epidermis without epidermal necrosis. The patient was diagnosed with toxic erythema of chemotherapy and improved with application of triamcinolone 0.1% ointment twice daily without discontinuation of her EV infusions. Although a targeted therapy, EV commonly exhibits cutaneous side effects due to the expression of nectin-4 in the skin. Most cutaneous side effects are mild and can be managed symptomatically. However, severe drug-induced eruptions, such as toxic epidermal necrolysis, have been described. The histologic findings of EV associated skin eruptions can aid in correctly identifying the culprit drug and assist in management. This case provides insights for dermatologists by highlighting the common cutaneous side effects of EV and the associated histologic findings as this targeted therapy becomes increasingly utilized in the treatment of refractory neoplasms.

A Review of Bullous Dermatologic Adverse Events Associated with Anti-Cancer Therapy

The rapid evolution of anti-cancer therapy (including chemotherapy, targeted therapy, and immunotherapy) in recent years has led to a more favorable efficacy and safety profile for a growing cancer population, and the improvement of overall survival and reduction of morbidity for many cancers. Anti-cancer therapy improves outcomes for cancer patients; however, many classes of anti-cancer therapy have been implicated in the induction of bullous dermatologic adverse events (DAE), leading to reduced patient quality of life and in some cases discontinuation of life-prolonging or palliative therapy. Timely and effective management of adverse events is critical for reducing treatment interruptions and preserving an anti-tumor effect. Bullous DAE may be limited to the skin or have systemic involvement with greater risk of morbidity and mortality. We present the epidemiology, diagnosis, pathogenesis, and management of bullous DAE secondary to anti-cancer therapies to enable clinicians to optimize management for these patients.

Enfortumab vedotin in the treatment of urothelial cancers and beyond

Enfortumab vedotin (EV) is the first antibody-drug conjugate approved for locally advanced or metastatic urothelial cancers (la/mUCs), a disease group historically associated with limited prognosis and therapeutic options. EV consists of monomethyl auristatin E, a microtubule-disrupting agent linked to an antibody targeting Nectin-4. In clinical trials, EV demonstrated high response rates and superior survival in the third-line setting for la/mUC compared with chemotherapy. Peripheral neuropathy and rash were among the most common serious adverse events. EV is currently approved in multiple countries for the treatment of la/mUC in the later-line setting. Ongoing trials seek to expand the indication for EV and to study therapeutic combinations with other agents.