A melanoma subtype with intrinsic resistance to BRAF inhibition identified by receptor tyrosine kinases gene-driven classification

Dysregulation of receptor tyrosine kinases (RTKs) contributes to several aspects of oncogenesis including drug resistance. In melanoma, distinct RTKs have been involved in BRAF inhibitors (BRAFi) resistance, yet the utility of RTKs expression pattern to identify intrinsically resistant tumors has not been assessed. Transcriptional profiling of RTKs and integration with a previous classification, reveals three robust subtypes in two independent datasets of melanoma cell lines and one cohort of melanoma samples. This classification was validated by Western blot in a panel of patient-derived melanoma cell lines. One of the subtypes identified here for the first time displayed the highest and lowest expression of EGFR and ERBB3, respectively, and included BRAF-mutant tumors all intrinsically resistant to BRAFi PLX4720, as assessed by analysis of the Cancer Cell Line Encyclopedia pharmacogenomic study and by in vitro growth inhibition assays. High levels of EGFR were detected, even before therapy, in tumor cells of one of three melanoma patients unresponsive to BRAFi. Use of different pharmacological inhibitors highlighted the relevance of PI3K/mTOR signaling for growth of this PLX4720-resistant subtype. Our results identify a specific molecular profile of melanomas intrinsically resistant to BRAFi and suggest the PI3K/mTOR pathway as a potential therapeutic target for these tumors.

Abstract A018: Onset of dysthyroidism during treatment with immune checkpoint inhibitors is increased in responder patients

Background: Immune checkpoints inhibitors (ICI) are characterized by a high therapeutic index; among toxicities, immune-related thyroiditis has been reported. The aim of this study is to evaluate either the grade and severity of thyroiditis or its frequency in responder patients.

Material and Methods: We retrospectively evaluated 104 metastatic solid tumor patients treated at our Institute with ICI from 2010. We defined thyroid toxicity according to CTCAE version 4.0 and the disease control rate (DCR: CR, PR, SD) as efficacy endpoint. Correlation between dysthyroidism and DCR was assessed by Fisher's exact test.

Results: Of 104 patients, 32 (30.8%) were treated by anti PD-1, 32 (30.8%) by anti PDL-1, 34 (32.7%) by anti CTLA-4 and 6 (5.7%) by combo (anti PD-1+anti CTLA-4). Population was heterogeneous, ranging from the first to the 8th line of therapy, and affected by the following cancers: 42 (40.4%) lung (38 NSCLC, 4 SCLC), 40 (38.5%) melanoma, 9 (8.6%) RCC, 7 (6.7%) gastric, 2 (1.9%) bladder and one each for colon, salivary glands, thyroid and uterine leiomiosarcoma. Best responses were: 3 CR, 14 PR, 33 SD and 54 PD; 50 (48%) of patients achieved DCR, 18 (37.5%) treated by anti PD-1, 16 (33.3%) by anti PDL-1, 12 (25%) by anti CTLA-2 (4.2%) by combo. Overall, 29 patients developed dysthyroidism (subclinic, G1, G2 hypo/hyperthyroidism): 2/34 (6%) in anti CTLA-4, 10/32 (31%) in anti PD-1, 13/32 (41%) in anti PDL-1, 4/6 (67%) in combo group, respectively; 19/29 (65.5%) of these patients achieved DCR. Of 75 patients who did not develop dysthyroidism, only 29 (38.6%) achieved DCR. The onset of dysthyroidism statistically significant correlated with DCR (65.5% vs 40.0%, p= 0.016); no correlation was detected between toxicity grade (subclinic and G1 from oneside, G2 from the other side) and DCR (p= 1.0).

Conclusions: In responding patients, we found a statistically significant increase of thyroiditis during treatment with ICI. Thyroid function evaluation should be recommended routinely during ICI therapy, in particular with anti PD-1 and anti PDL-1 agents. Finally, the role of thyroiditis in predicting response to ICI must be confirmed in a large and homogeneous series of patients.

Note:This abstract was not presented at the conference.

Citation Format: Diego Signorelli, Michele Del Vecchio, Marina Garassino, Alice Intini, Maria Silvia Cona, Michele Magni, Ettore Seregni, Massimo Di Nicola, Filippo De Braud. Onset of dysthyroidism during treatment with immune checkpoint inhibitors is increased in responder patients. [abstract]. In: Proceedings of the CRI-CIMT-EATI-AACR Inaugural International Cancer Immunotherapy Conference: Translating Science into Survival; September 16-19, 2015; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2016;4(1 Suppl):Abstract nr A018.

Vemurafenib in BRAFV600 mutated metastatic melanoma: a subanalysis of the Italian population of a global safety study

ABSTRACT 

Aim: We describe the ad interim analysis of the Italian cohort of the global safety study on vemurafenib in patients with metastatic melanoma. Patients & methods: A total of 385 patients received vemurafenib 960 mg twice daily. Results: In total, 330 patients (86%) reported adverse events; 16 serious adverse events were observed (three related to vemurafenib). The response rate was 30.4%. Median progression-free survival (PFS) and overall survival (OS) were 5.9 months and 16.3 months, respectively. In patients with brain metastasis (BM; n = 83), median PFS was 4.3 months and OS was 7.6 months. In patients without BM, PFS was 6.5 months and OS was not reached. Median PFS was 12.6 months in patients with M1a stage of disease, 9.6 months in those with M1b stage and 5.4 months in subjects with M1c stage. Conclusion: Vemurafenib appears safe and active in clinical practice, and seems particularly active in patients without BM and low tumor burden.

Clinical experience with ipilimumab 3 mg/kg: real-world efficacy and safety data from an expanded access programme cohort

BACKGROUND

Ipilimumab improves survival in patients with advanced melanoma. The activity and safety of ipilimumab outside of a clinical trial was assessed in an expanded access programme (EAP).

METHODS

Ipilimumab was available upon physician request for patients aged 16 or over with pretreated stage III (unresectable)/IV melanoma, for whom no other therapeutic option was available. Patients received ipilimumab 3 mg/kg every 3 weeks for four doses. Patients with stable disease or an objective response to ipilimumab were eligible for retreatment upon disease progression. Tumour assessments were conducted at baseline and week 12. Patients were monitored for adverse events (AEs) within 3 to 4 days of each scheduled visit.

RESULTS

Of 855 patients participating in the EAP in Italy, 833 were evaluable for response. Of these, 13% had an objective immune response, and the immune-related disease control rate was 34%. Median progression-free survival and overall survival were 3.7 and 7.2 months, respectively. Efficacy was independent of BRAF and NRAS mutational status. Overall, 33% of patients reported an immune-related AE (irAE). The frequency of irAEs was not associated with response to ipilimumab.

CONCLUSIONS

Outside of a clinical trial setting, ipilimumab is a feasible treatment option in patients with pretreated metastatic melanoma, regardless of BRAF and NRAS mutational status. Data from this large cohort of patients support clinical trial evidence that ipilimumab can induce durable disease control and long-term survival in patients who have failed to respond to prior treatment.

Efficacy and safety of ipilimumab in patients with advanced melanoma and brain metastases

Patients with melanoma brain metastases have a poor prognosis and historically have been excluded from clinical trials. The Expanded Access Program (EAP) provided an opportunity to evaluate the feasibility of ipilimumab (3 mg/kg every 3 weeks for four doses) in patients with stage 3 (unresectable) or 4 melanoma and asymptomatic brain metastases, who had failed or did not tolerate previous treatments and had no other therapeutic option available. Tumor assessments were conducted at baseline and week 12 using immune-related response criteria and patients were monitored for adverse events (AEs). Of 855 patients participating in the EAP in Italy, 146 had asymptomatic brain metastases. With a median follow-up of 4 months, the global disease control rate was 27%, including 4 patients with a complete response and 13 with a partial response. Median progression-free survival and overall survival were 2.8 and 4.3 months, respectively and approximately one-fifth of patients were alive 1 year after starting ipilimumab. In total, 29% of patients reported a treatment-related AE of any grade, which were grade 3/4 in 6% of patients. AEs were generally reversible with treatment as per protocol-specific guidelines. Ipilimumab shows durable benefits in some patients with advanced melanoma metastatic to the brain, with safety results consistent with those previously reported in clinical trials.

Vemurafenib in patients with BRAF(V600) mutated metastatic melanoma: an open-label, multicentre, safety study

BACKGROUND

The orally available BRAF kinase inhibitor vemurafenib, compared with dacarbazine, shows improved response rates, progression-free survival (PFS), and overall survival in patients with metastatic melanoma that has a BRAF(V600) mutation. We assessed vemurafenib in patients with advanced metastatic melanoma with BRAF(V600) mutations who had few treatment options.

METHODS

In an open-label, multicentre study, patients with untreated or previously treated melanoma and a BRAF(V600) mutation received oral vemurafenib 960 mg twice a day. The primary endpoint was safety. All analyses were done on the safety population, which included all patients who received at least one dose of vemurafenib. This report is the third interim analysis of this study. This study is registered with ClinicalTrials.gov, number NCT01307397.

FINDINGS

Between March 1, 2011, and Jan 31, 2013, 3226 patients were enrolled in 44 countries. 3222 patients received at least one dose of vemurafenib (safety population). At data cutoff, 868 (27%) patients were on study treatment and 2354 (73%) had withdrawn, mainly because of disease progression. Common adverse events of all grades included rash (1592 [49%]), arthralgia (1259 [39%]), fatigue (1093 [34%]), photosensitivity reaction (994 [31%]), alopecia (826 [26%]), and nausea (628 [19%]). 1480 (46%) patients reported grade 3 or 4 adverse events, including cutaneous squamous cell carcinoma (389 [12%]), rash (155 [5%]), liver function abnormalities (165 [5%]), arthralgia (106 [3%]), and fatigue (93 [3%]). Grade 3 and 4 adverse events were reported more frequently in patients aged 75 years and older (n=257; 152 [59%, 95% CI 53-65] and ten [4%, 2-7], respectively) than in those younger than 75 years (n=2965; 1286 [43%, 42-45] and 82 [3%, 2-3], respectively).

INTERPRETATION

Vemurafenib safety in this diverse population of patients with BRAF(V600) mutated metastatic melanoma, who are more representative of routine clinical practice, was consistent with the safety profile shown in the pivotal trials of this drug.

FUNDING

F Hoffmann-La Roche.

Sequential treatment with ipilimumab and BRAF inhibitors in patients with metastatic melanoma: data from the Italian cohort of the ipilimumab expanded access program

Of 93 patients with pretreated, BRAF(V600) mutation-positive advanced melanoma who received vemurafenib or dabrafenib before (n = 45) or after (n = 48) treatment with ipilimumab 3 mg/kg, median overall survival (mOS) from first treatment was 9.9 and 14.5 months, respectively. Among patients treated with a BRAF inhibitor first, mOS from the end of BRAF inhibition was 1.2 months for those who did not complete ipilimumab treatment as per protocol, compared with 12.7 months for those who did (p < .001). Prospective, randomized studies are required to determine the optimal sequencing of ipilimumab and BRAF inhibitors in patients with BRAF-mutated metastatic melanoma.

Interferon alpha for the adjuvant treatment of melanoma: review of international literature and practical recommendations from an expert panel on the use of interferon

The degree to which interferon (IFN) alpha-2b offers real clinical benefits in the adjuvant therapy of melanoma at high risk of recurrence is a subject of debate. This, together with questions over optimal treatment scheme and concerns over toxicity, has limited its clinical use. On the basis of a review of the literature, an Italian Expert Panel has made practical recommendations for a consistent approach in the use of IFN. Although it is clear that more research into predictive factors to identify patients most likely to benefit from adjuvant IFN therapy is required, IFN remains the only currently available adjuvant option for melanoma. Based on meta-analyses of clinical trials, there is clear evidence that treatment with IFN is beneficial with regard to overall and recurrence-free survival (RFS). As such, IFN should be offered to patients who are at high risk of recurrence. Specific recommendations with regard to disease stage are provided.

T lymphocytes redirected against the chondroitin sulfate proteoglycan-4 control the growth of multiple solid tumors both in vitro and in vivo

PURPOSE

Because of its high expression on various types of tumors and its restricted distribution in normal tissues, chondroitin sulfate proteoglycan-4 (CSPG4) represents an attractive target for the antibody-based therapy of several solid tumors. We tested whether T cells transduced with a CSPG4-specific chimeric antigen receptor (CAR) inhibited the growth of CSPG4-expressing tumor cells both in vitro and in vivo.

EXPERIMENTAL DESIGN

We first independently validated by immunohistochemistry (IHC) the expression of CSPG4 in an extensive panel of tumor arrays and normal tissues as well as queried public gene expression profiling datasets of human tumors. We constructed a second-generation CSPG4-specific CAR also encoding the CD28 costimulatory endodomain (CAR.CSPG4). We then evaluated human T lymphocytes expressing this CAR for their ex vivo and in vivo antitumor activity against a broad panel of solid tumors.

RESULTS

IHC showed that CSPG4 is highly expressed in melanoma, breast cancer, head and neck squamous cell carcinoma (HNSCC), and mesothelioma. In addition, in silico analysis of microarray expression data identified other important potential tumors expressing this target, including glioblastoma, clear cell renal carcinoma, and sarcomas. T lymphocytes genetically modified with a CSPG4-CAR controlled tumor growth in vitro and in vivo in NSG mice engrafted with human melanoma, HNSCC, and breast carcinoma cell lines.

CONCLUSIONS

CAR.CSPG4-redirected T cells should provide an effective treatment modality for a variety of solid tumors.

Abstract A89: Loss of HLA molecules as melanoma resistance mechanism in immune checkpoint blockade therapy

Melanoma immunotherapy based on immune checkpoint blockade, by targeting of CTLA-4 or PD-1, has markedly improved the treatment of advanced disease, as shown by several recent trials. Monotherapy with CTLA-4-specific antibody (Ipilimumab) prolongs overall survival, while PD-1-specific antibodies (Nivolumab and Lambrolizumab) induce durable tumor regression in a large fraction of patients. Moreover, a recent trial based on combination checkpoint blockade (Ipilimumab plus Nivolumab) has shown an objective response rate of 53%, with tumor reduction of 80% in responding patients, without escalation of toxic effects. In spite of these highly relevant results, clinical benefit by immunotherapy targeting CTLA-4 or PD-1 remains limited to a fraction of patients. This points to the existence of immune escape mechanisms, which, in some tumors, may prevent effective elimination of neoplastic cells, in spite of the reactivated T cell immunity. This hypothesis was tested in a melanoma patient, treated with Ipilimumab, and that we recently reported (J. Clin. Oncol. 29:e783-8, 2011) to have a strong T cell infiltrate and evidence of T cell maturation/activation only in a regressing right adrenal metastasis, but not in the progressing controlateral lesion. To this end, we carried out DASL whole genome gene expression analysis and extensive immunohistochemistry (IHC) on paraffin-embedded neoplastic tissues. The results indicated that, in comparison to the progressing metastasis, the regressing lesion had a distinct gene expression profile characterized by enhanced expression of several genes involved in T cell differentiation to cytolytic effector stage. Most importantly, the regressing lesion retained expression of HLA molecules on neoplastic cells. In contrast, the progressing lesion showed almost complete loss of HLA class I and Class II molecules by the tumor, as documented by IHC. Taken together, these results suggest that lack/loss of expression of HLA molecules, by tumor cells, may represent a highly effective tumor resistance mechanism to immune checkpoint blockade. Moreover, pre-therapy IHC on tumor samples may allow to test whether HLA antigen expression/loss is a predictive marker for response/resistance to therapy targeting CTLA-4 or PD-1.

Citation Information: Mol Cancer Ther 2013;12(11 Suppl):A89.

Citation Format: Andrea Anichini, Filippo G. de Braud, Roberta Montarini, Ilaria Bersani, Gabrina Tragni, Loris de Cecco, Silvana Canevari, Lorenza Di Guardo, Lorenzo Pilla, Michele Del Vecchio. Loss of HLA molecules as melanoma resistance mechanism in immune checkpoint blockade therapy. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr A89.

Future perspectives in melanoma research. Meeting report from the "Melanoma Bridge. Napoli, December 2nd-4th 2012"

Recent insights into the genetic and somatic aberrations have initiated a new era of rapidly evolving targeted and immune-based treatments for melanoma. After decades of unsuccessful attempts to finding a more effective cure in the treatment of melanoma now we have several drugs active in melanoma. The possibility to use these drugs in combination to improve responses to overcome the resistance, to potentiate the action of immune system with the new immunomodulating antibodies, and identification of biomarkers that can predict the response to a particular therapy represent new concepts and approaches in the clinical management of melanoma. The third "Melanoma Research: "A bridge from Naples to the World" meeting, shortened as "Bridge Melanoma Meeting" took place in Naples, December 2 to 4th, 2012. The four topics of discussion at this meeting were: advances in molecular profiling and novel biomarkers, combination therapies, novel concepts toward integrating biomarkers and therapies into contemporary clinical management of patients with melanoma across the entire spectrum of disease stage, and the knowledge gained from the biology of tumor microenvironment across different tumors as a bridge to impact on prognosis and response to therapy in melanoma. This international congress gathered more than 30 international faculty members who in an interactive atmosphere which stimulated discussion and exchange of their experience regarding the most recent advances in research and clinical management of melanoma patients.

Efficacy and safety data from elderly patients with pretreated advanced melanoma in the Italian cohort of ipilimumab expanded access programme (EAP)

9548

Background: Ipilimumab was the first agent approved for the treatment of unresectable or metastatic melanoma that showed an overall survival benefit in randomised phase III trials. Here we evaluate the safety and efficacy of ipilimumab treatment outside of clinical trials in elderly (>70 years old) patients (pts) enrolled in the EAP in Italy. Methods: Ipilimumab was available upon physician request for pts aged ≥16 years with unresectable stage III/IV melanoma who had either failed systemic therapy or were intolerant to ≥1 systemic treatment and for whom no other therapeutic option was available. Ipilimumab 3 mg/kg was administered intravenously every 3 weeks for 4 doses. Disease evaluation was performed at baseline and after completion of induction therapy using immune-related response criteria. Patients were monitored for adverse events (AEs), including immune-related AEs, using Common Terminology Criteria for Adverse Events v.3.0. Results: Out of 855 Italian pts participating in the EAP from June 2010 to January 2012 across 55 centres, 193 (22.6%) were over 70 years old (median 75; 70-88). Of these, 132 pts (68.4%) received all 4 doses of ipilimumab, 24 (12.4%) 3 doses, 17 (8.8%) 2 doses and 20 pts (10.4%) received 1 dose. With a median follow-up of 7.6 months (range 1-26), the disease control rate among 188 pts evaluable for response was 38.3%, including 4 pts (2.1%) with a complete response, 24 (12.8%) with a partial response and 44 (23.4%) with stable disease. As of December 2012, median progression-free survival and overall survival were 3.7 months and 8.9 months respectively, with 1-year survival rate of 38%. In total, 96 pts (49.7%) reported an AE of any grade, which were considered treatment-related in 69 pts (35.7%), with a safety profile comparable to the general population. Grade 3/4 AEs were reported by 19 pts (9.8%) and drug-related in 11 pts (5.7%). AEs were generally reversible with treatment as per protocol-specific guidelines with a median time to resolution of 2.0 weeks. Conclusions: Based on the data from EAP, ipilimumab is a feasible treatment in the elderly population; efficacy and safety results were similar to those observed in the general population.

Sequential treatment with ipilimumab and BRAF inhibitors in patients with metastatic melanoma: Data from the Italian cohort of ipilimumab expanded access programme (EAP)

9035

Background: Ipilimumab and vemurafenib have recently been approved as single agents for the treatment of unresectable or metastatic melanoma. Currently, limited data exist on the sequential treatment with these agents in patients (pts) with the BRAF mutation; here we evaluate the efficacy outcomes of pts enrolled in the EAP in Italy who sequentially received a BRAF-inhibitor and ipilimumab, or vice versa. Methods: Ipilimumab was available upon physician request for pts aged ≥16 years with unresectable stage III/stage IV melanoma who had either failed systemic therapy or were intolerant to ≥1 systemic treatment and for whom no other therapeutic option was available. Ipilimumab 3 mg/kg was administered intravenously every 3 weeks for 4 doses. Tumour assessments were conducted at baseline and after completion of induction therapy using immune-related response criteria. Patients were considered for this analysis if they tested positive for the BRAF mutation and had received a BRAF-inhibitor before or after ipilimumab treatment. Results: In total, 855 Italian pts participated in the EAP from June 2010 to January 2012 across 55 centres. Out of 173 BRAF positive pts, 93 (53.7%) were treated sequentially with both treatments: 48 pts received a BRAF inhibitor upon disease progression with ipilimumab and 45 pts received ipilimumab upon disease progression with a BRAF inhibitor. As of December 2012, median overall survival was 14.5 months (11.1-17.9) and 9.7 months (4.6-14.9) for the two groups, respectively (p=0.01). Among the 45 BRAF inhibitors pretreated pts, 18 (40%) had rapid disease progression (median overall survival: 5.8 months) and were unable to complete all four induction doses of ipilimumab, while the remaining 27 (60%) pts had slower disease progression (median overall survival: 19.3 months) and were able to complete the therapy with ipilimumab. Conclusions: These preliminary results suggest that, in BRAF-mutated pts, to start the sequential treatment with ipilimumab can provide a better survival than the reverse sequence. These findings deserve confirmation in a prospective study.

A phase III trial of nab-paclitaxel versus dacarbazine in chemotherapy-naive patients (pts) with metastatic melanoma: Analysis of peripheral neuropathy

e20025

Background: Peripheral neuropathy (PN) is a common side effect associated with taxane treatment. In a phase III trial, nab-paclitaxel vs dacarbazine demonstrated a significant improvement in progression-free survival (4.8 vs 2.5 months; P = 0.044) and at the interim survival analysis, a trend toward prolonged overall survival (12.8 vs 10.7 months; P = 0.094) for the treatment of chemotherapy-naive patients with metastatic melanoma. Here we report on the PN profile of nab-paclitaxel in this phase III trial. Methods: Pts (median age, 63 years) with chemotherapy-naive stage IV melanoma (M1c stage, 65%; elevated LDH, 28%) and an ECOG performance status 0-1 were randomized to nab-paclitaxel 150 mg/m2 on days 1, 8, and 15 of a 28-day cycle (n = 264) or dacarbazine 1000 mg/m2on day 1 of each 21-day cycle (n = 265). PN events were defined based on the Standardized MedDRA Query (V 12.1, broad scope). Results: As expected, a higher proportion of pts receiving nab-paclitaxel vs dacarbazine had ≥ 1 treatment-related PN event (68% vs 8%; P < 0.001). Treatment-related grade ≥ 3 PN was more frequent with nab-paclitaxel vs dacarbazine (25% vs 0%; P < 0.001); 2 grade 4 events were reported in the nab-paclitaxel arm. Treatment-related grade ≥ 3 PN was 15% in pts who received up to the median of 3 cycles of nab-paclitaxel. PN led to dose reduction in 13% or discontinuation in 15% of nab-paclitaxel–treated pts. The median time to onset of grade ≥ 3 PN was 101 days (95% CI, 85 - 113). Most early-onset PN events, occurring within the first 3 cycles, were grade 1. Grade ≥ 2 PN events peaked by cycle 4 and subsided by cycle 9. Forty-one of the 64 (64%) pts with a grade ≥ 3 PN event had an improvement of ≥ 1 grade, with a median time to improvement of 28 days (95% CI, 17 - 64), and 33 of 64 (52%) pts had improved to grade 1 or better by a median of 67 days from onset (95% CI, 22- upper limit not estimable); 30 of 64 (47%) pts resumed treatment with nab-paclitaxel. Conclusions: In this phase III trial, grade ≥ 3 PN was the main treatment-related toxicity with nab-paclitaxel as observed in other studies. However, PN was rapidly reversible; a majority of pts had improvement of PN symptoms within 1 month and resumed treatment. Clinical trial information: NCT00864253.

Correlation between efficacy and toxicity in pts with pretreated advanced melanoma treated within the Italian cohort of the ipilimumab expanded access programme (EAP)

9065

Background: Ipilimumab was the first agent approved for the treatment of unresectable or metastatic melanoma that showed an overall survival benefit in randomised phase III trials. Early clinical studies explored the potential relationship between immune-related adverse events (irAEs) associated with ipilimumab and antitumor activity but no definitive conclusion has been reached. Here, we evaluated the possible correlation between efficacy of ipilimumab treatment and irAEs in patients (pts) enrolled in the EAP in Italy. Methods: Ipilimumab was available upon physician request for pts aged ≥16 years with unresectable stage III/stage IV melanoma who had either failed systemic therapy or were intolerant to ≥1 systemic treatment and for whom no other therapeutic option was available. Ipilimumab 3 mg/kg was administered intravenously every 3 weeks for 4 doses. Tumour assessments were conducted at baseline and after completion of induction therapy using immune-related response criteria. Pts were monitored for adverse events (AEs), including immune-related AEs (irAEs), using Common Terminology Criteria for Adverse Events v.3.0. Results: In total, 855 Italian pts participated in the EAP from June 2010 to April 2012 across 55 centres. Among 833 evaluable pts, 278 pts (33.4%) reported an irAE and 555 (66.6%) did not. As of December 2012, the disease control rates among pts with or without irAEs were 35.3% and 33.9% respectively. We noted that there was a difference in the distribution of pts with or without irAEs among pts who experienced a fast progression, thus not being able to receive at least 3 cycles, and pts with slow progression. In fact, due to the mechanism of action of the drug and consequent delayed onset of irAEs, pts with irAEs among fast and slow progressors were 22% and 37% respectively. Therefore, median overall survival was evaluated by adjusting the 2 groups for this factor and results showed a comparable survival between pts who reported an irAE and pts who did not (10.0 vs 9.7 months respectively). Conclusions: This exploratory analysis of EAP data suggest that activity and efficacy of ipilimumab is not related with the occurrence of irAEs.

Open-label, multicenter safety study of vemurafenib in patients with BRAFV600 mutation–positive metastatic melanoma

9046

Background: Vemurafenib (VEM), a BRAF kinase inhibitor, has demonstrated high response rates and improved progression-free and overall survival in pts with BRAFV600mutation–positive metastatic melanoma (mM). We present interim results from predefined subgroups from a large multicenter, open-label safety study of VEM in pts with mM (NCT01307397). Methods: Pts with BRAFV600mutation–positive histologically confirmed mM received VEM (960 mg BID) as first-line therapy or subsequent to previous therapies. Assessments for safety and efficacy were made every 28 days. Results: As of Feb 29, 2012, 2,265 pts have received VEM. Pts had a median age of 54.0 (13-95) yrs and median time since diagnosis of mM of 6.2 (0-351.9) mos. 59% had received prior systemic therapy. Median time of exposure to VEM as of the cut-off date was 3 (0.03-11.24) mos for the overall population and majority of subgroups, and approximately 2.5 mos for pts with ECOG ≥2 and age ≥75 yrs. 1537 (68%) pts were still receiving VEM at the cut-off date. 728 (32%) pts discontinued, most frequently because of PD (538/728 pts; 74%). Adverse events (AEs) were reported for 87% of all patients, with arthralgia (32%) and rash (26%) the most frequent. The incidences of AEs in the subgroups are summarized (Table). Although efficacy analyses are limited by the short duration of follow-up, six-month OS rate was 76% (95% CI 72-79%) and median PFS was 4.1 mos (95% CI 3.9-4.5 mos). Postbaseline tumor assessments were available for 63% and 30% of pts at wk 8 and 16, respectively. At wk 8 CR: 2%, PR: 57%, SD: 30%, PD: 6%. At wk 16 CR: 3%, PR: 46%, SD: 31%, PD: 15%. Conclusions: Although the overall safety profile of VEM in this study was consistent with previous clinical data, interim analyses of subgroups suggest that very elderly pts may be at higher risk of G3 AEs. Clinical trial information: NCT01307397. [Table: see text]

A phase III trial of nab-paclitaxel versus dacarbazine in chemotherapy-naive patients with metastatic melanoma: A subanalysis based on BRAF status

9030

Background: Activating mutations of BRAF V600 can be found in 40%-50% of melanomas and are related to poor prognosis. In a phase 3 trial for the treatment of metastatic melanoma (MM) in chemotherapy-naive patients, nab-paclitaxel (nab-P) vs dacarbazine (DTIC) demonstrated a significant improvement in the primary endpoint of progression-free survival (PFS), assessed by independent radiological review (IRR), and a trend toward prolonged overall survival (OS) at the interim survival analysis. The study also explored the effect of BRAF status on the efficacy parameters. Methods: Chemotherapy-naive patients with stage IV melanoma (M1c stage 65%; elevated LDH 28%) and ECOG performance status 0-1 were randomized to nab-P 150 mg/m2 on days 1, 8, and 15 of a 28-day cycle (n = 264) or DTIC 1000 mg/m2 on day 1 of each 21-day cycle (n = 265) independent of BRAF status. Prespecified subgroup analyses of final PFS and interim OS in subgroups by BRAF status (V600E mutant, wild-type, or unknown) were performed. Results: BRAF mutation status was balanced between the treatment arms, with 36% and 38% of patients with known BRAF mutation status in the nab-P and DTIC arms, respectively. Patient characteristics were also balanced within BRAF subgroups. As shown in the Table, advantage in the nab-P arm vs DTIC arm was observed for both PFS and interim OS regardless of BRAFmutation status. Poststudy BRAF inhibitor treatment was also balanced. Conclusions: In this phase III trial, treatment effect was independent of BRAF mutation status, benefiting all patients who received nab-P vs DTIC. Therefore nab-P should be considered in the armamentarium for all chemotherapy-naive patients with MM. Clinical trial information: NCT00864253. [Table: see text]

Lenvatinib combined with dacarbazine versus dacarbazine alone as first-line treatment in patients with stage IV melanoma

9027

Background: Lenvatinib (E7080; LEN) is an oral, receptor tyrosine kinase inhibitor targeting VEGFR1-3, FGFR1-4, RET, KIT and PDGFRβ . In a phase I study qd dosing of >/= 20mg LEN demonstrated PRs and prolonged SD in patients (pts) with advanced melanoma. Dacarbazine (DTIC) upregulates the proangiogenic factor VEGF and has been shown to confer resistance in melanoma cell lines (Lev, JCO 2004; 22:2092-2100). Treatment of melanoma pts with LEN + DTIC may potentiate the therapeutic effects of DTIC. Methods: This was a phase II study in pts with metastatic melanoma randomized 1:1 to receive LEN (20 mg QD) + DTIC (1000 mg/m2 Q 21 d) or DTIC (1000 mg/m2Q 21 d). Pts were stratified by LDH level and stage IV subclass. Eligible pts were ECOG PS 0/1 and had no prior systemic therapies. BRAF status was determined from circulating tumor DNA. The primary endpoint was PFS by independent assessment. Results: In a modified ITT analysis,a total of 78 of 81 pts were evaluable for efficacy; 59% were male, 59% were Stage IV M1c, 22% had elevated LDH, 29% had prior adjuvant therapy and 49% BRAF wild-type (wt). Most common AEs in the LEN + DTIC arm were hypertension (48%), nausea (38%), constipation (33%), and diarrhea (31%). Most common Grade 3/4 AEs in LEN + DTIC were hypertension (26%) and neutropenia (10%). There were no deaths due to an AE. Median PFS increased in LEN + DTIC compared to DTIC alone (see Table). An improvement in median PFS was observed in BRAFwt pts on the combination. Conclusions: A 2.7-fold increase in the median PFS was observed in pts administered LEN + DTIC compared to single agent DTIC. A 2.5 fold increase in the median PFS was observed in the combination arm in pts with BRAFwt melanoma. The AE profile observed with the LEN + DTIC was consistent with observed LEN monotherapy studies. These data suggest further evaluation of LEN + DTIC in BRAFwt melanoma is warranted. Clinical trial information: NCT01133977. [Table: see text]

Italian cohort of ipilimumab expanded access programme (EAP): Efficacy, safety, and correlation with mutation status in metastatic melanoma patients

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Background: Ipilimumab was the first agent approved for the treatment of unresectable or metastatic melanoma to show a survival benefit in randomised phase III trials. Efficacy and safety of ipilimumab treatment outside of clinical trials and the correlation with BRAF and NRAS mutation status were evaluated. Methods: Ipilimumab was available upon physician request for patients (pts) aged ≥16 years with unresectable stage III/stage IV melanoma who had either failed systemic therapy or were intolerant to ≥1 systemic treatment and for whom no other therapeutic option was available. Ipilimumab 3 mg/kg was administered intravenously every 3 weeks for 4 doses. Tumour assessments were conducted at baseline and after completion of induction therapy using immune-related response criteria. BRAF and NRAS mutation status was retrospectively collected for all available pts. Patients were monitored for adverse events, including immune-related AEs, using Common Terminology Criteria for Adverse Events v.3.0. Results: In total, 855 Italian pts participated in the EAP from June 2010 to January 2012 across 55 centres. With a median follow-up of 6.5 months (range 0.5-30), the disease control rate among 833 pts evaluable for response was 34.3%: 28 pts (3.4%) with complete response, 83 (10.0%) with partial response and 175 (20.9%) with stable disease. As of December 2012, median progression-free survival and overall survival were 3.3 months and 7.2 months respectively, with 1-year survival rate of 36%. The Table shows mutation status for available patients. Disease control rates were comparable among pts with BRAF positive tumors and BRAF wild-type (37.5% vs 39.5%) and among pts with NRAS positive tumors and NRAS wild-type (57.1% vs 49.3%). Survival curves were also comparable between groups. 399 pts (46.7%) had a AEs of any grade, with 286 (33.5%) considered IrAEs. IrAEs were reversible with protocol specific guidelines. Conclusions: Based on EAP data, ipilimumab is an effective and safe treatment for pretreated pts with metastatic melanoma regardless BRAF and NRAS mutation status. [Table: see text]