Vemurafenib in BRAF-mutant metastatic melanoma patients in real-world clinical practice: prognostic factors associated with clinical outcomes

BRAF/MEK inhibitor rechallenge in advanced melanoma patients

BACKGROUND

Effectivity of BRAF(/MEK) inhibitor rechallenge has been described in prior studies. However, structured data are largely lacking.

METHODS

Data from all advanced melanoma patients treated with BRAFi(/MEKi) rechallenge were retrieved from the Dutch Melanoma Treatment Registry. The authors analyzed objective response rate (ORR), progression-free survival (PFS), and overall survival (OS) for both first treatment and rechallenge. They performed a multivariable logistic regression and a multivariable Cox proportional hazards model to assess factors associated with response and survival.

RESULTS

The authors included 468 patients in the largest cohort to date who underwent at least two treatment episodes of BRAFi(/MEKi). Following rechallenge, ORR was 43%, median PFS was 4.6 months (95% confidence interval [CI], 4.1-5.2), and median OS was 8.2 months (95% CI, 7.2-9.4). Median PFS after rechallenge for patients who discontinued first BRAFi(/MEKi) treatment due to progression was 3.1 months (95% CI, 2.7-4.0) versus 5.2 months (95% CI, 4.5-5.9) for patients who discontinued treatment for other reasons. Discontinuing first treatment due to progression and lactate dehydrogenase (LDH) levels greater than two times the upper limit of normal were associated with lower odds of response and worse PFS and OS. Symptomatic brain metastases were associated with worse survival, whereas a longer treatment interval between first treatment and rechallenge was associated with better survival. Responding to the first BRAFi(/MEKi) treatment was not associated with response or survival.

CONCLUSIONS

This study confirms that patients benefit from rechallenge. Elevated LDH levels, symptomatic brain metastases, and discontinuing first BRAFi(/MEKi) treatment due to progression are associated with less benefit from rechallenge. A prolonged treatment interval is associated with more benefit from rechallenge.

Long-term survival of patients with advanced melanoma treated with BRAF-MEK inhibitors

Recent results of patients with advanced melanoma treated with first-line BRAF-MEK inhibitors in clinical trials showed 5-year survival in one-third of patients with a median overall survival (OS) of more than 2 years. This study aimed to investigate these patients' real-world survival and identify the characteristics of long-term survivors. The study population consisted of patients with advanced cutaneous melanoma with a BRAF-V600 mutated tumor who were treated with first-line BRAF-MEK inhibitors between 2013 and 2017. Long-term survival was defined as a minimum OS of 2 years from start therapy. The median progression-free survival (mPFS) and median OS (mOS) of real-world patients ( n  = 435) were respectively 8.0 (95% CI, 6.8-9.4) and 11.7 (95% CI, 10.3-13.5) months. Two-year survival was reached by 28% of the patients, 22% reached 3-year survival and 19% reached 4-year survival. Real-world patients often had brain metastases (41%), stage IV M1c disease (87%), ECOG PS ≥2 (21%), ≥3 organ sites (62%) and elevated LDH of ≥250 U/I (49%). Trial-eligible real-world patients had an mOS of 17.9 months. Patients surviving more than 2 years ( n  = 116) more often had an ECOG PS ≤1 (83%), normal LDH (60%), no brain metastases (60%), no liver metastases (63%) and <3 organ sites (60%). Long-term survival of real-world patients treated with first-line BRAF-MEK inhibitors is significantly lower than that of trial patients, which is probably explained by poorer baseline characteristics of patients treated in daily practice. Long-term survivors generally had more favorable characteristics with regard to age, LDH level and metastatic sites, compared to patients not reaching long-term survival.

Survival in adult patients with BRAFV600 mutation-positive advanced melanoma: a noninterventional ambispective study of patients with cobimetinib combined with vemurafenib during the French early access program: MELANIS study

Cobimetinib combined with vemurafenib was available in France in 2015 through a 'Temporary Authorization for Use' program (TAU, preapproval access pending its marketing on 2016) for patients with v-raf murine sarcoma viral oncogene homolog B1-mutant advanced melanoma. This study aimed to provide real-world outcomes in patients previously registered in this TAU. This noninterventional, ambispective, multicentre French study, conducted in patients previously registered in TAU, aimed to estimate overall survival (OS) and progression-free survival (PFS) and to describe the tolerability of the therapeutic combination. At first cobimetinib intake (in combination with vemurafenib), 88% of the 185 evaluable patients had disease stage IV (brain metastasis: 70% of them), 31% had elevated lactate dehydrogenases, and 10% had an Eastern Cooperative Oncology Group (ECOG) index ≥2. Median OS was 16.1 months (95% CI, 12.5-20.7). Brain metastasis ( P < 0.001), ECOG index ≥2 ( P = 0.007), and hepatic impairment ( P = 0.037) were found as independent factors significantly associated with shorter survival. Median PFS was 7.3 months (95% CI, 5.2-8.4). ECOG index ≥2 ( P = 0.006) was significantly associated with shorter PFS. Between cobimetinib start and inclusion, increased CPK (3% of patients), retinal serous detachment (3%), decreased left ventricular ejection fraction (3%), increased transaminases (3%), and rash (3%) were the most reported serious adverse events. This study provides real-world outcomes in France for the vemurafenib-cobimetinib combination available in patients with BRAF-mutant-advanced melanoma. Our data tend to confirm in the real-life setting that this combination therapy is effective in such patients, with a safety profile consistent with previous interventional studies.

Time to Next Treatment as a Meaningful Endpoint for Trials of Primary Cutaneous Lymphoma

Time to next treatment (TTNT) is an emerging endpoint in clinical studies of primary cutaneous T-cell lymphomas (CTCL), with utility as a surrogate marker for the “duration of clinical benefit”. TTNT provides a highly clinically meaningful endpoint that uniquely reflects not only the duration of treatment efficacy on disease and symptom control, but also incorporates the patient experience by accounting for patient compliance and tolerance to the studied therapy(s). Given the distinct challenges of pin-pointing the exact date of progression in patients with multi-compartmental CTCL, TTNT overcomes many of the shortcomings of conventional, disease-focused, clinical endpoints in primary CTCL research. Although widely accepted in clinical research for numerous other incurable malignancies, TTNT currently lacks a standardised definition. In this paper, we describe the value of TTNT as a clinical endpoint, review the applications of TTNT in primary CTCL research, and propose a standardised definition of TTNT to be applied in future clinical research of primary CTCL therapies.

Real-world treatment practice in patients with advanced melanoma

Introduction

The treatment outcomes of patients with advanced/metastatic melanoma were poor before the use of new therapeutic options.

Material and methods

A retrospective analysis was conducted among 287 patients with unresectable stage III and stage IV melanoma treated at the Maria Sklodowska-Curie National Research Institute of Oncology Cracow Branch, from 2013 to 2019. All enrolled patients were treated with immunotherapy (IT; consisting of pembrolizumab/nivolumab, or ipilimumab) or target therapy (TT; consisting of vemurafenib ±cobimetinib or dabrafenib ±trametinib) in at least one treatment line.

Results

mutation was detected in 152 (55%) patients. In general, the majority of patients (92%) were in very good or good condition (Eastern Cooperative Oncology Group [ECOG] 0 or 1). Brain metastasis was detected in 64 (22%) patients. Median OS and PFS in the experimental group from the beginning of the first-line treatment were 14.9 and 6.7 months, respectively. Across the study population, as a first-line treatment patients received IT, TT as well as CHT, and the median OS was 19.2, 12.6 and 15.9 months, respectively. Multivariate analysis confirmed that normal LDH levels, no brain metastases, ECOG 0, and objective response to the treatment were strong predictors of longer OS. For PFS, absence of brain metastases, ECOG 0, and treatment response were found to be predictive factors on multivariate analysis.

Conclusions

The administration of new therapies for the treatment of patients with advanced/disseminated melanoma significantly prolonged survival in this group of patients. Nevertheless, further studies should be conducted to assess the effectiveness of various sequences of treatment.

Emerging insights of tumor heterogeneity and drug resistance mechanisms in lung cancer targeted therapy

The biggest hurdle to targeted cancer therapy is the inevitable emergence of drug resistance. Tumor cells employ different mechanisms to resist the targeting agent. Most commonly in EGFR-mutant non-small cell lung cancer, secondary resistance mutations on the target kinase domain emerge to diminish the binding affinity of first- and second-generation inhibitors. Other alternative resistance mechanisms include activating complementary bypass pathways and phenotypic transformation. Sequential monotherapies promise to temporarily address the problem of acquired drug resistance, but evidently are limited by the tumor cells' ability to adapt and evolve new resistance mechanisms to persist in the drug environment. Recent studies have nominated a model of drug resistance and tumor progression under targeted therapy as a result of a small subpopulation of cells being able to endure the drug (minimal residual disease cells) and eventually develop further mutations that allow them to regrow and become the dominant population in the therapy-resistant tumor. This subpopulation of cells appears to have developed through a subclonal event, resulting in driver mutations different from the driver mutation that is tumor-initiating in the most common ancestor. As such, an understanding of intratumoral heterogeneity-the driving force behind minimal residual disease-is vital for the identification of resistance drivers that results from branching evolution. Currently available methods allow for a more comprehensive and holistic analysis of tumor heterogeneity in that issues associated with spatial and temporal heterogeneity can now be properly addressed. This review provides some background regarding intratumoral heterogeneity and how it leads to incomplete molecular response to targeted therapies, and proposes the use of single-cell methods, sequential liquid biopsy, and multiregion sequencing to discover the link between intratumoral heterogeneity and early adaptive drug resistance. In summary, minimal residual disease as a result of intratumoral heterogeneity is the earliest form of acquired drug resistance. Emerging technologies such as liquid biopsy and single-cell methods allow for studying targetable drivers of minimal residual disease and contribute to preemptive combinatorial targeting of both drivers of the tumor and its minimal residual disease cells.

Inpatient palliative chemotherapy is associated with high mortality and aggressive end-of-life care in patients with advanced solid tumors and poor performance status

Background

The benefit of palliative chemotherapy (PC) in patients with advanced solid tumors and poor performance status (ECOG-PS) has not been prospectively validated, which makes treatment decision challenging. We aimed to evaluate the overall survival, factors associated with early mortality, and adoption of additional procedures in hospitalized patients with advanced cancer and poor ECOG-PS treated with PC.

Methods

We analyzed a retrospective cohort of patients with advanced cancer treated with PC during hospitalization at an academic cancer center in Brazil from 2014 to 2016. Eligibility criteria included: ECOG-PS 3–4 and start of first-line PC; or ECOG-PS ≥ 2 and start of second or subsequent lines. Primary endpoint was 30-day survival from start of PC. Kaplan-Meier method was used for survival estimates and Cox regression for factors associated with 30-day mortality.

Results

Two hundred twenty-eight patients were eligible. 21.9, 66.7 and 11.4% of patients had ECOG-PS 2, 3 and 4, respectively. 49.6% had gastrointestinal tumors. Median follow-up was 49 days (range 1–507). 98.2% of patients had died, 32% during the index hospitalization. The 30-day and 60-day survival rates were 55.7 and 38.5%, respectively. 30% of patients were admitted to the intensive care unit. In a multivariable analysis, ECOG-PS 3/4 (HR 2.01; P = 0.016), hypercalcemia (HR 2.19; P = 0.005), and elevated bilirubin (HR 3.17; P <  0.001) were significantly associated with 30-day mortality.

Conclusions

Patients with advanced cancer and poor ECOG-PS had short survival after treatment with inpatient PC. Inpatient PC was associated with aggressive end-of-life care. Prognostic markers such as ECOG-PS, hypercalcemia and elevated bilirubin can contribute to the decision-making process for these patients.