Combination of pembrolizumab plus temozolomide therapy in unresectable and advanced melanoma: a multicenter retrospective analysis in China

A Phase Ib Study of Selinexor in Combination with Pembrolizumab in Patients with Metastatic Melanoma

Immune checkpoint inhibitors (ICIs) have substantially advanced the treatment of patients with malignant melanoma. However, improving therapeutic efficacy requires identifying drug combinations that elicit durable responses without inducing intolerable toxicity. Within that context, selinexor emerges as a possible combination option that has been shown in preclinical studies to enhance the efficacy of ICI therapy. Methods: In this phase 1b study, we investigated selinexor in combination with pembrolizumab in 25 patients with advanced non-uveal melanoma. Patients received selinexor at a dosage of 60 mg taken orally twice weekly, and pembrolizumab intravenously at a dosage of 200 mg every 3 weeks. Results: Despite the high incidence of adverse events (96%), most treatment-related toxicities were manageable with supportive care and dose reductions. The most common adverse events of any grade were nausea (n = 20; 80%), decreased white blood cell count (n = 15; 60%), vomiting (n = 14; 56%), anemia (n = 12; 48%), fatigue (n = 12; 48%), and decreased platelet count (n = 12; 48%). The 10 patients with treatment-naïve evaluable disease had an objective response rate (ORR) of 70% (n = 7, including three patients with complete response), which was significantly higher than that of the 14 patients with prior anti-programmed cell death protein 1 (anti-PD-1) therapy, whose ORR was 7% (n = 1; p = 0.002). Stable disease was observed in two patients (20%) with treatment-naïve disease and seven patients (50%) with prior anti-PD-1 therapy. Conclusion: Selinexor combined with pembrolizumab showed promising antitumor activity in patients with treatment-naïve metastatic melanoma. The toxicity profile of the combination was consistent with that reported for individual agents, with no additional safety concerns.

Efficacy and safety of PD-1 monoclonal antibody combined with interferon-alpha 1b and anlotinib hydrochloride as the second-line therapy in patients with unresectable advanced melanoma: A retrospective study

BACKGROUND

Immune-checkpoint inhibitors are now used more commonly in combination than monotherapy as the first-line choice in patients with unresectable advanced melanoma. Nevertheless, for cases that progressed after the initial combination therapy, the subsequent regimen option can be very difficult. Herein, we reported the efficacy and safety of a triple combination regimen in Chinese unresectable advanced melanoma patients who had poor responses to the first-line immune therapy.

METHODS

We reviewed the clinical profiles of patients diagnosed with stage IIIC-IV melanoma between June 1, 2020, and September 30, 2023. The patients who failed the prior immune therapies and received anti-PD-1 mono antibody plus interferon(IFN)-alpha 1b and anlotinib hydrochloride as the second-line therapy were enrolled in the retrospective analysis. Additionally, we examined the exhaustion of T-cells using mIHC staining in available tumor samples.

RESULTS

Fifty-five patients were included in this study. The median follow-up period was 13.6 months. The objective response rate evaluated by the investigators was 9.1%(1CR, 4PR). The disease control rate was 47.3%. The median overall survival was 17.6 months, and the median progression-free survival was 2.8 months. The adverse events rate of any grade was 100%. Grade 3 or 4 irAEs were observed in 29.1% of cases. Multiplex immunohistochemical staining revealed an increased trend of TIM3 expression on tumor-infiltrating T cells in patients without objective response.

CONCLUSION

PD-1 monoclonal antibody plus interferon-alpha 1b plus anlotinib showed acceptable tolerability and anticancer benefits in Chinese metastatic melanoma patients as a second-line therapy.

Clinical Characteristics and Special Considerations in the Management of Rare Melanoma Subtypes

Rare histologic subtypes of melanoma, including acral, mucosal, uveal, and desmoplastic melanomas, only make up 5% of all diagnosed melanomas and are often underrepresented in large, randomized trials. Recent advancements in systemic therapy have shown marked improvement in pathologic response rates, improving progression-free and overall survival among cutaneous melanoma patients, but there are limited data to demonstrate improved survival among rarer subtypes of melanoma. Acral melanoma has a poor response to immunotherapy and is associated with worse survival. Mucosal melanoma has a large variability in its presentation, a poor prognosis, and a low mutational burden. Uveal melanoma is associated with a high rate of liver metastasis; recent adoption of infusion and perfusion therapies has demonstrated improved survival among these patients. Desmoplastic melanoma, a high-risk cutaneous melanoma, is associated with high locoregional recurrence rates and mutational burden, suggesting this melanoma may have enhanced response to immunotherapy. While these variants of melanoma represent distinct disease entities, this review highlights the clinicopathologic characteristics and treatment recommendations for each of these rare melanomas and highlights the utility of modern therapies for each of them.

The role of dacarbazine and temozolomide therapy after treatment with immune checkpoint inhibitors in malignant melanoma patients: A case series and meta-analysis

Dacarbazine (DTIC) and its oral counterpart temozolomide (TMZ) have been the most used agents in advanced malignant melanoma (MM) patients and they are still used routinely. The preferred first line treatment, immune checkpoint inhibitors (CPIs) might shape the tumor and the tumor microenvironment, possibly affecting the response to subsequent therapies. The aim of this study was to investigate the treatment effect of DTIC/TMZ in MM patients after CPI therapy in a consecutive patient cohort and through systematic literature review and meta-analysis. Thirty-five patients with advanced MM treated with DTIC/TMZ after previous CPI therapy in three Swedish regions between 2017 and 2021 were recognized and seven case series studies were identified through systematic database review. Pooled data from all 345 patients showed a median real-world progression-free survival (rwPFS) of 1.9 months and overall survival (OS) of 6.0 months. Three of these studies were included in a meta-analysis comparing DTIC/TMZ after CPI treatment, versus no previous immunotherapy, showing no statistically significant differences in rwPFS or OS but higher real-world response rate to chemotherapy for the prior-CPI treated group (Odds Ratio: 2.24; 95% Confidence Interval: 1.04-4.86). The current study supports consideration of DTIC/TMZ in later line of treatment in the immunotherapy era.

Effects of temozolomide on tumor mutation burden and microsatellite instability in melanoma cells

The efficacy of combination therapy with an immune checkpoint inhibitor (ICI) and cytotoxic chemotherapeutic agents has been investigated in cancer, including melanoma. Before ICIs were introduced, dacarbazine or temozolomide (TMZ) were used to treat melanoma. Several studies using glioma or colorectal cancer cells showed that TMZ can increase the tumor mutation burden (TMB) and induce mismatch repair (MMR) deficiency associated with microsatellite instability (MSI). These could increase immunoreactivity to an ICI, but this has not been evaluated in melanoma cells. We investigated the effects of TMZ on MSI status and TMB in melanoma cells. To evaluate the TMB, we performed whole-exome sequencing using genomic DNA from the human melanoma cell lines Mel18, A375, WM266-4, G361, and TXM18 before and after TMZ treatment. Polymerase chain reaction amplification of five mononucleotide repeat markers, BAT25, BAT26, NR21, NR24, and MONO27, was performed, and we analyzed changes in the MSI status. In all cell lines, the TMB was increased after TMZ treatment (the change amount of TMB with ≤ 5% variant allele frequency [VAF] was 18.0-38.3 mutations per megabase) even in the condition without obvious cytological damage. MSI after TMZ treatment was not observed in any cells. TMZ increased TMB but did not change MSI status in melanoma cells.

Therapeutic Responses to Combination Nivolumab and Temozolomide as Salvage Therapy for Metastatic Melanoma: A Case Series

The management of metastatic melanoma patients that fail multiple lines of systemic therapy remains a significant challenge. There is limited literature regarding combination of anti-PD-1 and temozolomide, or of other chemotherapy agents, in melanoma. Here, we present a series of 3 patients with metastatic melanoma and their responses to nivolumab and temozolomide combination therapy after progression on several local/regional therapies, combination immune checkpoint inhibitors, and/or targeted therapies. The novel combinatory strategy led to remarkable responses in all 3 patients shortly after initiating treatment with tumor remission and symptomatic improvement. The first patient has had ongoing response 15 months after initiating treatment, although he has since discontinued temozolomide due to intolerance. The remaining 2 patients show ongoing response after 4 months, with good tolerability. This case series suggests that nivolumab and temozolomide may be a promising option in the setting of advanced melanoma refractory to standard treatments, and warrants further investigation in larger series.

Efficacy of salvage therapies after failure of adjuvant anti-PD-1 monotherapy for melanoma in the Chinese population: a multi-institutional cohort study

The majority of melanoma patients experience relapse during adjuvant therapy or after the end of therapy. Sixty-one patients from 3 melanoma centres who experienced recurrence and received adjuvant pembrolizumab for resected stage III/IV melanoma were enrolled. Disease characteristics, recurrence characteristics, subsequent management and outcomes were retrospectively analysed. Sixty-one patients were enrolled in this study. The median time to first relapse from the commencement of adjuvant pembrolizumab was 8 months (1-22 months). The first recurrences were locoregional alone in 25 patients (41%), distant alone in 29 (47.5%) and concurrent locoregional and distant relapse in 7 (11.5%). At the first recurrence, 4 patients (80%) who underwent resection alone experienced further relapse of disease. Three (60%) patients who were treated with adjuvant pembrolizumab following surgery, 2 (100%) patients who were treated with adjuvant chemotherapy, 2 (66.7%) patients who were treated with adjuvant chemotherapy and pembrolizumab combined and 3 (100%) patients who were treated with adjuvant radiotherapy and pembrolizumab combined had further recurrence. Of the three patients treated with adjuvant BRAF/MEKi following the first relapse, none had yet recurred. Of the 8 patients treated with pembrolizumab alone, only one patient (12.5%) who recurred after ceasing adjuvant PD1 had a partial response. The overall response rate to BRAF/MEKi was 75%, 3/4; to pembrolizumab in combination with an oral multitargeted receptor tyrosine kinase inhibitor, it was 22.2%, 2/9; to chemotherapeutic agents alone, it was 33.3%, 1/3; and to chemotherapeutic agents combined with pembrolizumab, it was 37.5%, 3/8. The patient treated with imatinib had progressive disease after 3 months of treatment. Of the 6 patients who received temozolomide combined with pembrolizumab, 3 (3/6, 50%) had a partial response. The median OS of the patients who relapsed locoregionally only was longer than that of the patients who relapsed distally at the first recurrence (35 months and 14 months, respectively; P < 0.01). The outcomes of the patients with disease recurrence during or after the completion of 1 year of adjuvant anti-PD1 therapy were poor despite multimodality treatment.

Efficacy and safety of interferon-alpha 1b combined with PD-1 monoclonal antibody in patients with unresectable stage IV melanoma: a retrospective study

PURPOSE

The low objective response of immune checkpoint inhibitors (ICIs) remains a great challenge in advanced melanoma therapy. Interferon-alpha has been proven to be a promising combination regimen with ICI in a phase Ib/II trial. Herein, we evaluated the efficacy and safety of interferon-alpha 1b plus PD-1 monoantibody in a real-world Chinese metastatic melanoma cohort.

METHODS

Profiles of patients diagnosed with unresectable stage IV (AJCC 8th Edition) between December 1st, 2018 and February 28th, 2022 from the Department of Dermatology, Xijing Hospital were reviewed. All of them received the combination treatment of interferon-alpha 1b (600 μg every other day) plus PD-1 monoantibody (Pembrolizumab 2 mg/kg or Toripalimab 240 mg or Sintilimab 200 mg, every 3 weeks) for at least 12 weeks. The efficacy was assessed by Response Evaluation Criteria in Solid Tumors (RECIST V1.1). The safety data were identified according to Common Terminology Criteria for Adverse Events (CTC AE) V.5.0.

RESULTS

In total, 70 patients were included. 50% were females. 52.9% were with ECOG performance status ≥ 1. The fraction of patients receiving Pembrolizumab, Toripalimab, and Sintilimab was 28.6%, 67.1%, and 4.3%, respectively. Acral and mucosal subtypes accounted for 48.6% and 20%. The median follow-up period is 15.1 months. The objective response rate was 32.8%. The median time of overall survival was 18 months (95% CI 14.2-21.8 months), and the median time of PFS was 5.2 months (95% CI 4.2-6.2 months). The incidence of adverse events (any grade) was 98.6%, but only 8.6% of cases experienced grade 3 or 4 adverse reactions.

CONCLUSION

The combination of interferon-alpha 1b and PD-1 monoantibody demonstrated promising anti-tumor effects and acceptable toxicity in Chinese metastatic melanoma patients with cutaneous, acral, and mucosal subtypes.

Advanced Acral Melanoma Therapies: Current Status and Future Directions

Melanoma is one of the deadliest malignancies. Its incidence has been significantly increasing in most countries in recent decades. Acral melanoma (AM), a peculiar subgroup of melanoma occurring on the palms, soles, and nails, is the main subtype of melanoma in people of color and is extremely rare in Caucasians. Although great progress has been made in melanoma treatment in recent years, patients with AM have shown limited benefit from current therapies and thus consequently have worse overall survival rates. Achieving durable therapeutic responses in this high-risk melanoma subtype represents one of the greatest challenges in the field. The frequency of BRAF mutations in AM is much lower than that in cutaneous melanoma, which prevents most AM patients from receiving treatment with BRAF inhibitors. However, AM has more frequent mutations such as KIT and CDK4/6, so targeted therapy may still improve the survival of some AM patients in the future. AM may be less susceptible to immune checkpoint inhibitors because of the poor immunogenicity. Therefore, how to enhance the immune response to the tumor cells may be the key to the application of immune checkpoint inhibitors in advanced AM. Anti-angiogenic drugs, albumin paclitaxel, or interferons are thought to enhance the effectiveness of immune checkpoint inhibitors. Combination therapies based on the backbone of PD-1 are more likely to provide greater clinical benefits. Understanding the molecular landscapes and immune microenvironment of AM will help optimize our combinatory strategies.

The pharmacotherapeutic management of nail unit and acral melanomas

INTRODUCTION

Acral and nail unit melanomas are rare subtypes of melanoma, which have poor prognoses. Current guidelines for optimal treatment are lacking. Recent clinical trials have evaluated new pharmacotherapeutic agents for melanoma treatment, with dramatically improved survival rates; however, studies on acral and nail unit melanomas are limited in comparison to trials on cutaneous melanoma.

AREAS COVERED

This is a comprehensive review of the literature regarding the available treatment options for acral and nail unit melanomas, with consideration of safety and tolerability.

EXPERT OPINION

Programmed cell death protein 1 inhibitors are more efficacious than cytotoxic T lymphocyte-associated antigen-4 blockers in acral and nail unit melanomas, although both are well-tolerated. Tyrosine kinase inhibitors have good clinical activity, however, data on safety is relatively limited. There is minimal data on high dose interferon α-2b and cyclin-dependent kinase 4 and 6 inhibitors, and efficacy and safety must be evaluated in future trials before they can be recommended for use in this patient population. Prospective clinical trials on acral and nail unit melanomas are lacking, and must be performed in large patient populations, with international collaboration likely necessary in order to enroll adequate participants.