- Email: [email protected]
6 inhibitor) in combination with binimetinib (MEK162; MEK inhibitor) in patients with NRAS-mutant melanoma
Abstracts and refractory MM patients a significant humoral immune response against proteins related with these three conditions. Materials and Methods: We studied repository serum with clinical data included in MGUS, na¨ıve and refractory MM. We performed a systematic multivariate analysis of proteins overexpressed in monoclonal gammopathy as representative of a potential start to create preventive vaccines for MM and in refractory cancer patients who progress despite treatment. We found four potential oncogenic drivers such as HIF-1 alpha, RAD51, Sox2 and Mcl-1. Afterwards we performed an antigen–specific indirect ELISA for both IgG and IgA using recombinant proteins to interrogate human MGUS na¨ıve and refractory MM serum and demonstrated if they were immunogenic. Results: Using indirect ELISA both antigen specific IgG and IgA using recombinant proteins with the four proteins we only found a statistical difference for anti-Mcl-1 specific IgG in MGUS (p = 0.01), na¨ıve MM (p = 0.005) and relapsed MM (p = 0.05). For anti-Mcl-1 IgA we found in MGUS (p=0001), na¨ıve MM (p = 0.002) and relapsed MM (p = 0.01). Here, we showed that even in refractory MM the antigenspecific humoral immune response was detected and it was clear that patients with the highest immune responses had better clinical outcomes in terms of OS. Discussion: MM is a challenging hematological malignancy and immune therapy is a good possibility for treatment either to prevent recurrence or in combination to improve the outcomes of the current standard of care treatment. We showed that one out of the four proteins had biological and clinical relevance in MGUS, na¨ıve and relapsed MM is immunogenic both for IgG and IgA. We will move forward to prepare a peptide vaccine and test animal immunogenicity for Mcl-1. Also it could be a good approach in combination with standard of care treatment in progressive or active disease to improve clinical outcomes. No conflict of interest.
Proffered Paper Session (Monday, 28 September) Melanoma and Skin Cancer 3300 ORAL A phase 1b/2 study of ribociclib (LEE011; CDK4/6 inhibitor) in combination with binimetinib (MEK162; MEK inhibitor) in patients with NRAS-mutant melanoma C. Van Herpen1 , M.A. Postow2 , M.S. Carlino3 , H. Kalkavan4 , A. Weise5 , R.N. Amaria6 , F. De Vos7 , R.D. Carvajal8 , A. Matano9 , S. Bhansali10 , L. Lam11 , P. Yerramilli-Rao11 , J.A. Sosman12 . 1 Radboud University Nijmegen Medical Center, Oncology, Nijmegen, Netherlands; 2 Weill Cornell Medical College, Memorial Sloan Kettering Cancer Center, Medical Oncology, New York, NY, USA; 3 Westmead and Blacktown Hospitals and Melanoma Institute Australia, Medical Oncology, Sydney, New South Wales, Australia; 4 University Duisburg-Essen, Oncology, Essen, Germany; 5 Karmanos Cancer Institute, Oncology, Detroit, MI, USA; 6 University of Texas MD Anderson Cancer Center, Melanoma Medical Oncology, Houston, TX, USA; 7 University Medical Center Utrecht, Oncology, Utrecht, Netherlands; 8 Columbia University Medical Center, Oncology, New York, NY, USA; 9 Novartis Pharma AG, Oncology, Basel, Switzerland; 10 Novartis Pharmaceuticals Corporation, Oncology, East Hanover, NJ, USA; 11 Novartis Institutes for BioMedical Research, Oncology, Cambridge, MA, USA; 12 Vanderbilt University Medical Center, Oncology, Nashville, TN, USA Background: NRAS-mutant cutaneous melanoma (15−20% of cases) has been responsive to the MEK inhibitor binimetinib (MEK162). Enhanced MAPK pathway signaling and cell cycle check point dysregulation are frequent in NRAS-mutant melanoma; thus, simultaneous inhibition of MEK and CDK4/6 may suppress pathway activation. Combined ribociclib (LEE011; CDK4/6 inhibitor) and binimetinib has shown promising preliminary antitumor activity in advanced NRAS-mutant melanoma (Sosman et al. ASCO 2014; NCT01781572). Updated efficacy and safety data for this study are reported here. Materials and Methods: This is a phase 1b/2, open-label study of ribociclib + binimetinib in patients with NRAS-mutant melanoma. The primary objective of the phase 1b part is to estimate the maximum-tolerated dose (MTD)/recommended phase 2 dose (RP2D) of the combination, using a Bayesian Logistic Regression Model (BLRM) with overdose control principle. Secondary objectives include safety, pharmacokinetics, and preliminary efficacy. Two dosing schedules are being explored: 28-day cycle, ribociclib once daily (QD) for 21 days + binimetinib twice daily (BID) continuously; or 21-day cycle, ribociclib QD + binimetinib BID, both for 14 days each cycle. Results: As of 15 August 2014, 22 patients (ECOG PS 0/1/2, 41%/50%/9%) were treated at 4 different ribociclib/binimetinib combination
S663 dose levels (DLs) on the 28-day cycle: DL1, 200/45 mg (n = 9); DL2, 250/45 mg (n = 3); DL3, 300/30 mg (n = 4); and DL4, 300/45 mg (n = 6). Dose limiting toxicities included grade (gr) 3 acute renal injury (DL1, n = 1), fatal intracranial bleed (DL3, n = 1), gr 4 anemia (DL4, n = 1), gr 4 asymptomatic creatinine phosphokinase (CPK) elevation (DL4, n = 1), and gr 3 edema + gr 4 atrial fibrillation (DL4, n = 1). The MTD for the 28day cycle was determined to be DL1. Common treatment-related toxicities included elevated CPK, anemia, rash, nausea, edema, diarrhea, elevated creatinine, elevated phosphate, neutropenia, and vomiting. Exposure of both drugs in this combination was consistent with respective single-agent data. Partial response (PR) was achieved by 5 patients (23%), unconfirmed PR by 4 patients (18%), and 9 (41%) had stable disease. Several patients experienced early tumor shrinkage with major symptomatic improvement. Preliminary median progression-free survival was estimated to be 6.2 mo (95% CI, 3.7-not estimable). No patients currently remain on 28-day cycle treatment. Exploration of the 21-day cycle is ongoing with an MTD not yet determined (n = 22). To date, ribociclib/binimetinib doses up to 300/45 mg have been assessed and 450/45 mg is currently being tested. Conclusions: Combined ribociclib + binimetinib continues to show promising preliminary antitumor activity in patients with NRAS-mutant melanoma. Determination of RP2D and schedule is ongoing. Conflict of interest: Corporate-sponsored Research: Novartis.
3301 ORAL Two year estimate of overall survival in COMBI-v, a randomized, open-label, phase III study comparing the combination of dabrafenib (D) and trametinib (T) with vemurafenib (Vem) as first-line therapy in patients (pts) with unresectable or metastatic BRAF V600E/K mutation-positive cutaneous melanoma C. Robert1 , B. Karaszewska2 , J. Schachter3 , P. Rutkowski4 , A. Mackiewicz5 , D. Stroyakovskiy6 , M. Lichinitser7 , R. Dummer8 , F. Grange9 , L. Mortier10 , V. Chiarion-Sileni11 , K. Drucis12 , I. Krajsova13 , A. Hauschild14 , B. Mookerjee15 , J. Legos15 , D. Schadendorf16 . 1 Gustave-Roussy, Villejuif Paris, France; 2 Przychodnia Lekarska “Komed”, Konin, Poland; 3 Sheba Medical Center, Tel-Hashomer, Ramat-Gan, Israel; 4 Maria Sklodowska-Curie Memorial Cancer Center and Institute of Oncology, Warsaw, Poland; 5 Poznan University of Medical Sciences, Poznan, Poland; 6 Moscow City Oncology Hospital #62, Moscow, Russia; 7 N.N. Blokhin Russian Cancer Research Center, Moscow, Russia; 8 University Hospital Zurich, Zurich, Switzerland; 9 Centre ´ Reims, France; 10 CHRU Lille, Hospitalier Universitaire Robert Debre, University Lille II, Lille, France; 11 Veneto Oncology Institute, Padua, Italye; 12 Swissmed Centrum Zdrowia SA, Medical University, Gdansk, Poland; 13 VFN a 1LF UK Praha, Prague, Czech Republic; 14 University Hospital Schleswig-Holstein, Kiel, Germany; 15 GlaxoSmithKline, Collegeville, PA, USA; 16 University Hospital Essen, Essen, Germany Background: This Phase III study (NCT01597908) of dabrafenib (D) + trametinib (T) compared with vemurafenib (Vem) demonstrated a 31% reduction in the risk of death for D+T compared with Vem (HR = 0.69; 95% CI: 0.53–0.89; p = 0.005) in pts with BRAF V600E/K mutant, metastatic melanoma at the interim analysis (N Engl J Med 2015; 372: 30−9). The adjusted stopping boundary for efficacy (p < 0.0214) was crossed at the interim analysis and the study was stopped for efficacy by the Independent Data Monitoring Committee (IDMC). Rates of adverse events (AEs) were similar for both arms. There was a higher incidence of pyrexia and ejection fraction decrease with D+T, and a lower incidence of cutaneous malignancies, hyperproliferative events, and photosensitivity with D+T compared to Vem. Methods: Pts were randomized 1:1 to receive D (150 mg twice daily) + T (2 mg once daily) or Vem (960 mg twice daily) as first-line therapy. Eligible pts were 18 years, ECOG performance status 1, and had histologically confirmed unresectable stage IIIC or IV, BRAF V600E/K mutant cutaneous melanoma. The primary endpoint was OS; secondary endpoints were PFS, overall response rate (ORR), duration of response (DoR), and safety. Results: From June 2012 to October 2013, 1,645 pts were registered and 704 were randomized 1:1 to one of two treatment arms (352 to D+T, 352 to Vem). The updated (March 13th 2015) OS analysis demonstrated a statistically significant improvement in OS for D+T over Vem (HR = 0.66 [95% CI: 0.53–0.81; p < 0.001]) and median OS of 25.6 vs 18 months. The updated analysis reported a statistically significant improvement in PFS for D+T over Vem (HR = 0.61 [95% CI: 0.51–0.73], p < 0.001) and median PFS of 12.6 and 7.3 months, respectively. The 2-year estimate of OS and updated efficacy and safety results will be presented.
S664 Conclusions: Updated OS analysis confirmed improvement in OS favoring D+T over Vem with medians of 25.6 versus 18 months. Two-year OS rates and additional efficacy and safety analysis will be presented. Conflict of interest: Ownership: J Legos reported equity ownership with GSK. B Mookerjee reported equity ownership with GSK, Incyte Corporation, and AstraZeneca. Advisory Board: P Rutkowski participated in an Advisory Committee for Novartis, Roche, BMS, and MSD. R Dummer participated in an Ad Board with Roche, BMS, GSK, MSD, Novartis. V Chiarion-Sileni participated in an Advisory Committee for BMS, GSK, Roche, and Merck. I Krajsova´ participated in an Advisory Committee for BMS. Board of Directors: P Rutkowski was a member of the board of directors for Novartis, Roche, BMS, and MSD. V Chiarion-Sileni was a member of the board of directors for BMS, GSK, Roche, and Merck. I was a member of the board of directors for BMS. Corporatesponsored Research: M Lichinitser received research funding from GSK. R Dummer received research funding from Roche, BMS, GSK, MSD, Novartis. K Drucis received research funding from GSK. A Hauschild received research funding from Amgen, BMS, Celgene, Eisai, GSK, MelaSciences, Merck Serono, MSD/Merck, Novartis, Oncosec, Roche Pharma. Other Substantive Relationships: C Robert acted as a consultant for GSK, Novartis, Merck, BMS, Amgen, and Roche. P Rutkowski received honoraria from Novartis, GSK, Roche, Amgen, Pfizer, BMS, MSD, and Bayer and participated in a speakers bureau for Novartis and Pfizer. L Mortier reports personal fees from GSK, during the conduct of the study. A Hauschild acted as a consultant for Amgen, BMS, Celgene, Eisai, GSK, MedImmune, MelaSciences, Merck Serono, MSD/Merck, Novartis, Oncosec, and Roche and received honoraria from Amgen, BMS, Celgene, Eisai, GSK, MedImmune, MelaSciences, Merck Serono, MSD/Merck, Novartis, Oncosec, and Roche. B Mookerjee and J Legos are employees of GSK. D Schadendorf acted as a consultant and received honoraria from, and participated in a speakers bureau for GSK, Novartis, Roche, Amgen, BMS, Boehringer Ingelheim, and Merck/MSD. 3302 ORAL Safety and Activity of Combined Radiotherapy (RT) and Anti-PD-1 Antibodies (PD-1) in Patients (pts) with Metastatic Melanoma E. Liniker1 , B. Kong2 , A.M. Menzies1 , A. Cooper2 , S. Ramanujam1 , S. Lo3 , R.F. Kefford2 , G.B. Fogarty4 , A. Guminski1 , T.W. Wang5 , M.S. Carlino2 , A. Hong4 , G.V. Long1 . 1 Melanoma Institute Australia, Medical Oncology, Sydney, Australia; 2 Crown Princess Mary Cancer Centre, Westmead, Medical Oncology, Sydney, Australia; 3 Melanoma Institute Australia, Statistics, Sydney, Australia; 4 Melanoma Institute Australia, Radiation Oncology, Sydney, Australia; 5 Crown Princess Mary Cancer Centre, Westmead, Radiation Oncology, Sydney, Australia Background: Prior studies suggest that RT can induce an abscopal immune response that may be enhanced with the addition of immunotherapy such as ipilimumab (ipi). This effect is thought to be driven via the release of tumour antigens and subsequent immune recognition. We sought to review the clinical outcomes of pts receiving RT immediately prior to or during PD1 therapy. Materials and Methods: All pts receiving pembrolizumab or nivolumab for unresectable stage III/IV melanoma who had sequential (4 weeks prior to PD1 commencement) or concurrent RT were identified. RT and systemic treatment, clinical outcome and toxicity data was collected. Results: Of all pts treated with PD1 at Melanoma Institute Australia and Westmead Hospital, 39 had either sequential RT (n = 10, 26%), concurrent RT (n = 26, 67%), or both (n = 3, 8%). Median time to RT was 8.5 days after commencing PD1 (range −28 to 185). 34 (89%) pts received prior ipi (median 3 doses, mean interval last ipi to PD1 72 days). 16 pts had brain metastases (BM) at start of PD1 (median no. of BM 4), 21 (54%) had an elevated LDH, and 29 (74%) had M1c disease. 27 (69%) had RT to extracranial sites, 4 (10%) had stereotactic RT (SRS) to BM and 4 (10%) had whole brain RT (WBRT). 4 (10%) had a combination of these. Of 32 evaluable pts at data cut, 9 (28%) had overall RECIST partial response (PR), none had complete response (CR). 5 (16%) had stable disease (SD). A total of 82 metastases were irradiated; 25 were clinically or radiologically progressing on PD1 at RT start and could be assessed for lesional response by RECIST criteria. 7 of 25 (28%) had subsequent PR, 3 (12%) had CR, and 5 (20%) continued to progress. In pts with BM, median progression free survival (PFS) and overall survival (OS) were 2.5 months and 6.8 months respectively, while in pts without BM PFS was 4.1 months and OS 16.4 months. No excess RT toxicity was observed except: cerebral radionecrosis in one pt 3 months after SRS that responded to bevacizumab and steroids; potential delayed neurotoxicity in a single pt with multiple small asymptomatic BMs treated with a single dose of ipi closely followed by PD1 and concurrent WBRT (20Gy/5#); disproportionate cerebral oedema in a pt with rapidly
Abstracts progressive BMs treated with concurrent ipi, PD1 and WBRT. Irradiated and non-irradiated lesion-specific and site-specific (intracranial and extracranial) response rates will be examined, and updated survival analyses will be performed. Conclusions: These results suggest that RT and PD1 can be safely coadministered with no excess acute extracranial toxicity. The potential for neurotoxicity with cerebral RT requires further investigation. RT can be effective for local control of lesions progressing on PD1. Conflict of interest: Advisory Board: Richard F Kefford − Educational funds to institution BMS, Merck. Honoraria for Educational Symposia: Merck, BMS. Advisory Boards: Merck, BMS, Novartis, GSK, Roche, Amgen. Matteo S Carlino − Merck Advisory Board, BMS Advisory Board. Georgina V. Long − Amgen Advisory Board, BMS Advisory Board, GSK Advisory Board, Merck Advisory Board, Novartis Advisory Board, Provectus Advisory Board, Roche Advisory Board. Other Substantive Relationships: Adam Cooper − sponsorship (partial scholarship) for PhD research from Novogen. Sangeetha Ramanujam − travel and accommodation grants from AMGEN for San Antonio Breast Symposium in 2013.
3303 ORAL Efficacy and safety in key patient subgroups of nivolumab (NIVO) alone or combined with ipilimumab (IPI) versus IPI alone in treatment-na¨ıve patients with advanced melanoma (MEL) (CheckMate 067) J. Larkin1 , V. Chiarion-Sileni2 , R. Gonzalez3 , J.J. Grob4 , C.L. Cowey5 , C.D. Lao6 , J. Wagstaff7 , D. Hogg8 , A. Hill9 , M.S. Carlino10 , P. Wolter11 , C. Lebbe´ 12 , J. Schachter13 , L. Thomas14 , J.C. Hassel15 , P. Lorigan16 , D. Walker17 , J. Jiang18 , F.S. Hodi19 , J.D. Wolchok20 . 1 Royal Marsden Hospital, Medical Oncologist, London, United Kingdom; 2 IOV-IRCCS-Melanoma Oncology Unit, Melanoma Cancer Unit, Padova, Italy; 3 University of Colorado Cancer Center, Division of ˆ Medical Oncology, Aurora CO, USA; 4 Aix-Marseille University-Hopital de La Timone APHM, Department of Dermatology and Skin Cancers, 5 Marseille, France; Baylor Charles A. Sammons Cancer Center, Hematology/Medical Oncology, Dallas TX, USA; 6 University of Michigan, Medical Oncology, Ann Arbor MI, USA; 7 South West Wales Cancer Institute-Singleton Hospital, Oncology Clinical Trials Unit, Swansea, United Kingdom; 8 Princess Margaret Hospital-University of Toronto, Clinical Studies Resource Center, Toronto ON, Canada; 9 Tasman Oncology Research, Department of Health, South Gold Coast QLD, Australia; 10 Melanoma Institute Australia and the University of Sydney, Medical Oncology, Sydney NSW, Australia; 11 UZ Leuven, Medical ˆ Oncology, Leuven, Belgium; 12 Hopital Saint-Louis University Paris Diderot, Department of Dermatology, Paris, France; 13 Oncology Institute, Ella Institute for the Treatment and Research of Melanoma and Skin Cancer at the Sheba Medical Center, Tel Hashomer, Israel; 14 Centre Hospitalier ´ Lyon Sud, Department of Dermatology, Pierre-Benite, France; 15 German Cancer Research Centre University Hospital, Department of Dermatology and National Center for Tumor Diseases, Heidelberg, Germany; 16 The Christie NHS Foundation Trust, Medical Oncology, Manchester, United Kingdom; 17 Bristol-Myers Squibb, Global Clinical Research, Princeton NJ, USA; 18 Bristol-Myers Squibb, Global Biometric Sciences, Hopewell NJ, USA; 19 Dana-Farber Cancer Institute, Department of Medicine-Harvard Medical School, Boston MA, USA; 20 Memorial Sloan Kettering Cancer Center and Weill Cornell Medical College, Melanoma and Immunotherapeutics Services, New York NY, USA Background: The CheckMate 067 phase III study compared NIVO (a PD-1 checkpoint inhibitor) or NIVO combined with IPI (a CTLA-4 checkpoint inhibitor) to IPI alone in patients (pts) with MEL. The combination of NIVO and IPI significantly improved progression-free survival (PFS) and objective response rate (ORR) versus IPI alone. Here, we report the results of subgroup analyses across the 3 treatment groups in this trial, including pts with poor prognostic factors. Material and Methods: Treatment-na¨ıve pts with MEL (N = 945) were randomized 1:1:1 to receive NIVO (3 mg/kg Q2W) + placebo (PBO), or NIVO + IPI (1 mg/kg + 3 mg/kg Q3W X 4) followed by NIVO 3 mg/kg Q2W, or to IPI (3 mg/kg Q3W X 4) + PBO until disease progression or unacceptable toxicity. PFS, a co-primary endpoint, was evaluated in predefined subgroups, including M stage of disease, serum lactate dehydrogenase (LDH) levels and BRAF mutation status. Results: Baseline characteristics of the pts were balanced across the 3 treatment arms, with 58% having M1c stage of disease, 36% having elevated LDH levels and 32% a BRAF V600 mutation. In the total population, median PFS was 11.5 months for NIVO + IPI versus 2.9 months for IPI alone (hazard ratio [HR] vs IPI, 0.42; P < 0.00001), and was 6.9 months for NIVO alone (HR vs IPI, 0.57; P < 0.00001). Numerically longer
Abstracts
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PFS was observed in the combination group versus NIVO or IPI alone in all predefined subgroups of pts (Table). The incidence of drug-related grade 3−4 adverse events was 55.0%, 16.3% and 27.3% in the NIVO + IPI, NIVO and IPI groups, respectively. Across pt subgroups, the safety profile was consistent with that observed in the overall safety population (eg, in pts 75 yr, 48%, 21% and 36% in the NIVO + IPI, NIVO and IPI groups, respectively, experienced drug-related grade 3−4 adverse events). Conclusions: In pts with treatment-na¨ıve MEL, NIVO + IPI and NIVO alone significantly improved PFS across predefined subgroups, including pts with poor prognostic factors. The safety profile of the combination was manageable across subgroups of pts.
Total population BRAF Wild-type Mutant M stage M0/M1a/M1b M1c Baseline LDH ULN >ULN Age (yr) <65 65 and <75 75
N N
Median PFS (95% CI) NIVO NIVO + IPI
IPI
945
6.9 (4.3−9.5)
11.5 (8.9–16.7)
2.9 (2.8−3.4)
645 300
7.9 (4.9–12.7) 5.6 (2.8−9.5)
11.2 (8.3−NR) 11.7 (8.0−NR)
2.8 (2.8−3.1) 4.0 (2.8−5.5)
386 559
9.3 (5.6−NR) 5.4 (2.8−8.9)
15.5 (11.2−NR) 8.5 (5.5–12.4)
4.2 (3.0−5.5) 2.8 (2.7−2.8)
589 341
10.2 (6.9–14.3) 2.8 (2.6−4.0)
14.0 (11.3−NR) 4.2 (2.8−9.3)
4.0 (3.0−5.2) 2.6 (2.6−2.8)
565 262 118
5.5 (3.0−8.3) 12.7 (6.7−NR) 5.3 (2.6−NR)
11.7 (7.0−NR) 11.1 (8.3–14.0) NR (4.4−NR)
2.8 (2.8−3.1) 2.9 (2.7−3.9) 4.0 (2.8−6.9)
NR, not reached; ULN, upper limit of normal.
Conflict of interest: Advisory Board: V. Chiarion-Sileni has had an advisory board/consulting role for Roche, Bristol-Myers Squibb, GlaxoSmithKline, and MSD. R. Gonzalez has had an advisory board/ consulting role with Roche and Piramal. J.J. Grob has had an advisory board/consulting role for Bristol-Myers Squibb, GlaxoSmithKline, Novartis, Amgen, Merck, and Roche. M.S. Carlino has had an advisory board/ consulting role for Bristol-Myers Squibb. P. Wolter has had an advisory board/consulting role for GlaxoSmithKline and Bristol-Myers Squibb. C. Lebbe´ has had an advisory board/consulting role for Bristol-Myers Squibb, MSD, Roche, GlaxoSmithKline, and Novartis. J.C. Hassel has had an advisory board/consulting role for Amgen and GlaxoSmithKline. P. Lorigan has had an advisory board/consulting role for Merck and Bristol-Myers Squibb. Corporate-sponsored Research: J. Larkin’s institution has received research funding from Pfizer, Bristol-Myers Squibb, Novartis, and MSD. R. Gonzalez’s institution has received research funding from GlaxoSmithKline, Roche, Genentech, Bristol-Myers Squibb, Merck, and Castle. J.J. Grob has received research funding from Roche and Bristol-Myers Squibb. C.L. Cowey has received research funding from Bristol-Myers Squibb, Merck, Genentech, Roche, and EMD Serono. P. Wolter has received research funding from GlaxoSmithKline, Pfizer, and Novartis. F.S. Hodi’s institution has received clinical trial support from Bristol-Myers Squibb, Merck, and Genentech. and he has received personal fees from Merck and Novartis. Other Substantive Relationships: V. Chiarion-Sileni has participated in speakers’ bureau for Roche, Bristol-Myers Squibb, and GlaxoSmithKline. and has received travel reimbursement from Roche, Bristol-Myers Squibb, GlaxoSmithKline, and MSD. R. Gonzalez has received honoraria from Bristol-Myers Squibb, Roche/Genentech, GlaxoSmithKline, Castle, and Amgen. J.J. Grob has participated in speakers’ bureau for GlaxoSmithKline, Roche, and Bristol-Myers Squibb. and has received travel reimbursement from Roche. C.L Cowey has employment and stock ownership with Texas Oncology, PA. has leadership with US Oncology-McKesson Specialty Health. has received honoraria from Novartis, Castle Biosciences, Celgene, Bristol-Myers Squibb, and Merck. has participated in speakers’ bureau for Bristol-Myers Squibb, and Merck. C.D. Lao has nothing to disclose. J. Wagstaff’s institution has received consulting fees from Bristol-Myers Squibb. A. Hill has employment from Tasman Oncology/Tasman Oncology Research. and has received travel reimbursement from Bristol-Myers Squibb. M.S. Carlino has received honoraria from Bristol-Myers Squibb. L. Thomas’ institution has received honoraria while he was PI at my center for the clinical trial reported herein. J.C. Hassel has received honoraria from Bristol-Myers Squibb, GlaxoSmithKline, MSD, and Amgen. has participated in speakers’ bureau for Bristol-Myers Squibb, GlaxoSmithKline, Roche, MSD, and Amgen. and has received travel reimbursement from Amgen and Bristol-Myers Squibb. P. Lorigan has received travel reimbursement from Merck and Bristol-Myers Squibb. F.S. Hodi has a patent Methods for treating MICA-related disorders with royalties paid, a patent Therapeutic Peptides pending, and a patent Tumor Antigens and Uses Thereof pending. D. Hogg, J. Schachter, D. Walker and J. Jiang have nothing to disclose.
3304 ORAL Metabolic activity in metastatic melanoma after long-term treatment with anti-PD-1 antibodies B. Kong1 , C. Saunders2,3,4 , E. Liniker5 , S. Ramanujam5 , A. Guminski4,5,6,7 , R. Scolyer4,5,8 , R. Kefford3,5 , A. Menzies4,5,6,7 , G. Long4,5,7 , M. Carlino1,4,5 . 1 Crown Princess Mary Cancer Centre, Medical Oncology, Sydney, Australia; 2 Westmead Hospital, Nuclear Medicine, Sydney, Australia; 3 Macquarie University, School of Advanced Medicine, Sydney, Australia; 4 University of Sydney, Medicine, Sydney, Australia; 5 Melanoma Institute Australia, Medical Oncology, Sydney, Australia; 6 Royal North Shore Hospital, Medical Oncology, Sydney, Australia; 7 Mater Hospital, Medical Oncology, Sydney, Australia; 8 Royal Prince Alfred Hospital, Anatomical Pathology, Sydney, Australia Background: Patients who receive anti-PD-1 antibodies for metastatic melanoma often have durable responses associated with radiological CR/PR/SD, however the metabolic activity and tumour viability of long term responders remains unknown. Materials and Methods: 18-F Fluorodeoxyglucose positron emission tomography CT (FDG-PET) scans were performed on patients treated with nivolumab or pembrolizumab for greater than twelve months on phase I-III clinical trials. Best overall radiological response (ORR) and response at time of PET scanning was determined using standard immune related response criteria (irRC). The presence of FDG-PET metabolic activity was classified by the visual inspection method. The metabolic activity of individual lesions identified on CT scans was subsequently characterised as PET positive or negative. Unexpected PET positive foci were included in the lesion-specific analysis even if not visible on prior CT. Biopsy or surgery was performed where clinically indicated to investigate the cause of unexpected or atypical lesions. Results: 27 patients underwent PET scans at a median of 15.2 months after starting treatment (Range 9.5–35.0 months). Best ORR was CR in 9 patients (33%), PR in 11 (41%), SD in 6 (22%) and PD in 1 (4%). At the time of PET scanning, 8 (29.6%) patients were in complete CT response (CR), 8 (29.6%) partial response (PR), 4 (14.8%) stable disease (SD) and 7 (25.9%) progressive disease (PD). A total of 62 individual lesions were identified on the CT scans prior to PET scanning, of which 34 (55%) were PET positive and 28 (45%) were PET negative. A further five PET positive lesions were identified which were not noted on CT. In patients who had not progressed via irRC (CR/PR/SD), 63% of their lesions were negative by PET. In contrast, in patients with disease progression (PD), 14% of their lesions negative by PET. Overall irRC response at time of PET
PET negative patients
PET positive patients
Biopsy of unexpected PET positive lesions
CR PR SD PD
6 4 2 0
2 4 2 7
2 1 1 1
lymphocytic infiltrate; 1 granuloma. melanoma melanoma granuloma; 3 melanoma
Six of eight (75%) CR patients had negative PET scans. Two of eight (25%) CR patients had PET positive scans, however biopsies excluded melanoma in both cases (lymphocytic infiltrate, granuloma). Four of 8 (50%) PR patients had no PET positive lesions. Conclusions: In patients with prolonged response to anti-PD1 therapy and residual disease on CT the majority of disease is metabolically inactive. In patients with a radiological CR, PET may be no more sensitive than CT in detecting recurrence. False positive results on PET may be due to treatment related granulomatous reactions, and biopsies of unexpected or atypical lesions should be considered to confirm or exclude disease progression. Conflict of interest: Ownership: Nil. Advisory Board: Amgen, BMS, GSK, Merck, Novartis, Provectus, Roche. Board of Directors: Nil. Corporatesponsored Research: Nil. Other Substantive Relationships: Honoraria paid by BMS, GSK, Merck, Provectus, Roche.
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Abstracts
3305 ORAL PD1 inhibition-induced changes in melanoma and its associated immune infiltrate R.E. Vilain1,2,3 , H. Kakavand1,2 , A.M. Menzies1,2 , J. Madore1,2 , J. Wilmott1,2 , R. Dobney1,2 , V. Jakrot1,2 , A.J. Cooper4 , B. Kong5 , S. Lo1,2 , E. Liniker1 , R.P. Saw1,2 , J.F. Thompson1,2 , R. Kefford1,2,5 , M.S. Carlino1,5,2 , G.V. Long1,2 , R.A. Scolyer1,2,3 . 1 Melanoma Institute Australia, Sydney, NSW, Australia; 2 The Sydney University, Sydney Medical School, Sydney, NSW, Australia; 3 Royal Prince Alfred Hospital, Tissue Pathology and Diagnostic Oncology, Sydney, Australia; 4 Liverpool Hospital, Department of Medical Oncology, Liverpool, Australia; 5 Westmead Hospital, Department of Medical Oncology, Westmead, Australia Background: The immune checkpoint inhibitors pembroluzimab and nivolumab disrupt PD-L1/cytotoxic T-cell PD1 signalling and improve survival in metastatic melanoma patients. To date, little is known about changes in tumoral PD-L1 expression and tumor-associated immune cell flux in melanoma patients undergoing these treatments. Materials and Methods: 49 tumor biopsies from 24 unresectable AJCC Stage III/IV metastatic melanoma patients receiving pembrolizumab/ nivolumab were analyzed. Tumor biopsies were collected prior to (PRE, n = 21) and within two months of commencing treatment (EDT, n = 21) and again on disease progression (PROG, n = 7). Patients exhibiting stable disease (n = 9), partial (n = 6) or complete (n = 1) regression on their best response on RECIST or iRC criteria were deemed responders. Response status was correlated with a histomorphological and immunohistochemical analysis. Results: PRE intra-tumoral and peri-tumoral density of PD1+ T-cells was 8.1-fold higher (p = 0.0142) and 6.8-fold higher (p = 0.0098) in responders and directly correlated with the degree of tumor shrinkage on radiology (r=-0.356, p = 0.0090 and r=-0.442, p = 0.0035, respectively). EDT biopsies revealed a significant influx of intra-tumoral CD3+, CD8+ and CD68+ macrophages in the responders, but not in non-responders. At EDT, the distribution of tumoral and macrophage PD-L1 expression was higher in responders (p = 0.0554 and p = 0.0379, respectively). PD-L1 expression was universally present in the tumor and macrophage cell components at PROG. A trend for an increase in intra-tumoral and peri-tumoral macrophage density at PROG was observed. Conclusions: The higher numbers of PD1+ T-cells in the PRE biopsies of responders suggests the active suppression of an engaged immune system, which is disinhibited by anti-PD1 therapies. Furthermore, it may also serve as a biomarker of treatment response. The increased PD-L1 expression in EDT biopsies of responders likely reflects disengagement of the PD-L1/PD1 axis, reactivation of PD1+ T-cells and increased interferong production. On the acquisition of resistance to PD1 inhibition, the lack of changes in PD-L1 expression or T-cell infiltrates suggests other mechanisms are involved in immune escape. Conflict of interest: Advisory Board: RK is a consultant advisor to Merck, BMS, GSK, Novartis and Roche as well as Honoraria from Merck, BMS, Roche and GSK and an unrestricted Educational Grant from BMS. MC is a consultant advisor to Merck and BMS. GL is a consultant advisor to Amgen, BMS, GSK, Novartis, Roche, and has received Honoraria.
Poster Session (Sunday, 27 September) Melanoma and Skin Cancer 3306 Immunological microenvironment of basal cell carcinoma
POSTER
Y. Przhedetsky1 , E. Zlatnik2 , N. Zakharova1 , E. Sharay1 , G. Zakora2 , A. Bakhtin2 . 1 Rostov Research Institute of Oncology, Department of Reconstructive and Plastic Surgery, Rostov-Don, Russian Federation; 2 Rostov Research Institute of Oncology, Department of Immunology, Rostov-Don, Russian Federation Background: Though basal cell carcinoma (BCC) is not metastatic, its tumor growth has become more aggressive in recent years. As it commonly appears on the face, surgical and radiotherapy options are limited. Local immunity in different types of BCC is of special scientific and clinical interest. The purpose of the study was to analyze the local immunity factors in BCC microenvironment in different tumor spread and patients’ parameters. Material and Methods: Tumor removal with subsequent plastic reconstruction for the postoperative defect was performed in 43 patients (24 women and 19 men aged 21−86) with primary (29) and recurrent (14) BCC from T1N0M0 to T4N0M0. Tumor fragments were homogenized,
lymphocyte populations and subpopulations were determined using BD FACSCanto II Flow Cytometer and a panel of antibodies to T-, B- and NKcells (CD45+, CD3, CD4, CD8, CD19, CD16/56) and levels of cytokines IL-1b, IL-6, IL-8 and TNF-a were defined by ELISA. Healthy skin tissue removed during plastic surgery served as the control. Results: Content of anti-inflammatory cytokines in BCC tissue exceeded the levels in healthy skin which was statistically significantly for IL-1b (50.0±6.5 against 17.2±7.5 pg/g of protein) and IL-8 (48.8±8.5 against 15.7±6.3 pg/g of protein). NK-cell level in tumor was lower (2.1±0.6 against 8.85±2.7%) and level of B-lymphocytes − higher (5.1±1.5 against 0.8±0.4% respectively) (p < 0.05 for all cases). Levels of IL-1b, IL-8 and NK-cells were higher in tumors of patients under 50 years old in comparison with the older patients. Content of CD3+CD4+ lymphocytes and IL-1b was higher in solid tumors than in infiltrative and superficial ones, and recurrent tumors differed from infiltrative ones in the lower TNF-a level (1.44±0.3 and 2.9±0.7 pg/g of protein respectively, p < 0.05) which was at the same time higher than in healthy tissue. The minimal level of TNF-a was observed in T4N0M0 tumors in comparison with T1-T3 ones. Conclusions: A number of immunological characteristics varying in different stages and variants of tumor and patients’ age were observed in BCC microenvironment; the common feature of all tumor variants was the high content of IL-1b and IL-8 cytokines in tissue of tumor which can assist its growth. No conflict of interest. 3307 POSTER An immunoglobulin VH CDR-3-derived peptide attenuates Hsp90 activity, binds to an adhesion GPCR and promotes hyperadherence, motility arrest and anti-melanoma metastatic activity N. Girola1 , A.L. Matsuo1 , C.R. Figueiredo1 , M.H. Massaoka1 , D.C. Arruda1 , C.F. Farias1 , R.A. Azevedo2 , L.R. Travassos1,3 . 1 Federal ˜ Paulo, Experimental Oncology Unit UNONEX, Sao ˜ Paulo, University of Sao Brazil; 2 Butantan Institute, Department of Biochemistry and Biophysics 3 ˜ Paulo, Brazil; Recepta Biopharma, Sao ˜ Paulo, SP, Brazil Laboratory, Sao Background: Malignant melanoma is a lethal skin cancer largely resistant to current therapies. Synthetic peptides are promising candidates for tumor therapy and currently, small peptides corresponding to complementaritydetermining regions (CDRs) from different immunoglobulins have been shown to induce anti-infective and antitumor activities regardless of the specificity of the original monoclonal antibody (mAb). The present work focused on the antitumor effects of a peptide (Rb9) derived from VH CDR 3 (H3) of an anti-NaPi3b mAb, using as target cells the B16F10-Nex2 murine melanoma lineage. The peptide effects on tumor cell adhesion, migration, invasion and metastasis in a syngeneic model and the cell signaling pathways were investigated. Materials and Methods: Tumor cell migration/invasion was assessed by the wound-healing and Matrigel® assays. Rb9 cell signaling in B16F10Nex2 cells was assessed by Western blotting, cAMP and calcium release assays. Rb9 binding to Hsp90 and the inhibition of its activity were determined by ELISA, using recombinant Hsp90 protein, and by the citrate synthase aggregation assay, respectively. The peptide also bound to the melanoma cell surface, as seen by confocal microscopy. Hsp90 and GPR124 internal peptides were used as Rb9 binding substrates. In vivo assays were performed with 6−8 weeks-old C57Bl/6 mice by intravenous challenge with B16F10-Nex2 melanoma cells. Results: Hsp90 and GPR124 are expressed on melanoma cells and Rb9, but not the Cys-less Rb10A1 control, bound to Hsp90, two Hsp-90 C-terminal peptides, and to a GPR124-GAIN domain peptide. Effects were: 1) inhibition of HSP90 chaperoning activity, down-activation of FAK, Src and Rac1 affecting cell migration; 2) GPR124-G-protein activation, induction of cAMP and Ca++, and PKA/VASP signaling; 3) Inhibition of murine melanoma lung metastasis in syngeneic mice. Altogether, the peptide caused tumor cell hyperadherence, motility arrest, invasion inhibition and anti-metastatic effects. Conclusion: The VH CDR-3-derived peptide (Rb9) binds to melanoma cell surface components modulating signaling pathways that lead to antitumor activity involving hyperadherence and inhibition of migration/ invasion. These effects warrant further development of a drug-peptide against malignant melanoma. Supported by FAPESP 2010–51423−0 No conflict of interest.
Proffered Paper Session (Monday, 28 September) Melanoma and Skin Cancer 3300 ORAL A phase 1b/2 study of ribociclib (LEE011; CDK4/6 inhibitor) in combination with binimetinib (MEK162; MEK inhibitor) in patients with NRAS-mutant melanoma C. Van Herpen1 , M.A. Postow2 , M.S. Carlino3 , H. Kalkavan4 , A. Weise5 , R.N. Amaria6 , F. De Vos7 , R.D. Carvajal8 , A. Matano9 , S. Bhansali10 , L. Lam11 , P. Yerramilli-Rao11 , J.A. Sosman12 . 1 Radboud University Nijmegen Medical Center, Oncology, Nijmegen, Netherlands; 2 Weill Cornell Medical College, Memorial Sloan Kettering Cancer Center, Medical Oncology, New York, NY, USA; 3 Westmead and Blacktown Hospitals and Melanoma Institute Australia, Medical Oncology, Sydney, New South Wales, Australia; 4 University Duisburg-Essen, Oncology, Essen, Germany; 5 Karmanos Cancer Institute, Oncology, Detroit, MI, USA; 6 University of Texas MD Anderson Cancer Center, Melanoma Medical Oncology, Houston, TX, USA; 7 University Medical Center Utrecht, Oncology, Utrecht, Netherlands; 8 Columbia University Medical Center, Oncology, New York, NY, USA; 9 Novartis Pharma AG, Oncology, Basel, Switzerland; 10 Novartis Pharmaceuticals Corporation, Oncology, East Hanover, NJ, USA; 11 Novartis Institutes for BioMedical Research, Oncology, Cambridge, MA, USA; 12 Vanderbilt University Medical Center, Oncology, Nashville, TN, USA Background: NRAS-mutant cutaneous melanoma (15−20% of cases) has been responsive to the MEK inhibitor binimetinib (MEK162). Enhanced MAPK pathway signaling and cell cycle check point dysregulation are frequent in NRAS-mutant melanoma; thus, simultaneous inhibition of MEK and CDK4/6 may suppress pathway activation. Combined ribociclib (LEE011; CDK4/6 inhibitor) and binimetinib has shown promising preliminary antitumor activity in advanced NRAS-mutant melanoma (Sosman et al. ASCO 2014; NCT01781572). Updated efficacy and safety data for this study are reported here. Materials and Methods: This is a phase 1b/2, open-label study of ribociclib + binimetinib in patients with NRAS-mutant melanoma. The primary objective of the phase 1b part is to estimate the maximum-tolerated dose (MTD)/recommended phase 2 dose (RP2D) of the combination, using a Bayesian Logistic Regression Model (BLRM) with overdose control principle. Secondary objectives include safety, pharmacokinetics, and preliminary efficacy. Two dosing schedules are being explored: 28-day cycle, ribociclib once daily (QD) for 21 days + binimetinib twice daily (BID) continuously; or 21-day cycle, ribociclib QD + binimetinib BID, both for 14 days each cycle. Results: As of 15 August 2014, 22 patients (ECOG PS 0/1/2, 41%/50%/9%) were treated at 4 different ribociclib/binimetinib combination
S663 dose levels (DLs) on the 28-day cycle: DL1, 200/45 mg (n = 9); DL2, 250/45 mg (n = 3); DL3, 300/30 mg (n = 4); and DL4, 300/45 mg (n = 6). Dose limiting toxicities included grade (gr) 3 acute renal injury (DL1, n = 1), fatal intracranial bleed (DL3, n = 1), gr 4 anemia (DL4, n = 1), gr 4 asymptomatic creatinine phosphokinase (CPK) elevation (DL4, n = 1), and gr 3 edema + gr 4 atrial fibrillation (DL4, n = 1). The MTD for the 28day cycle was determined to be DL1. Common treatment-related toxicities included elevated CPK, anemia, rash, nausea, edema, diarrhea, elevated creatinine, elevated phosphate, neutropenia, and vomiting. Exposure of both drugs in this combination was consistent with respective single-agent data. Partial response (PR) was achieved by 5 patients (23%), unconfirmed PR by 4 patients (18%), and 9 (41%) had stable disease. Several patients experienced early tumor shrinkage with major symptomatic improvement. Preliminary median progression-free survival was estimated to be 6.2 mo (95% CI, 3.7-not estimable). No patients currently remain on 28-day cycle treatment. Exploration of the 21-day cycle is ongoing with an MTD not yet determined (n = 22). To date, ribociclib/binimetinib doses up to 300/45 mg have been assessed and 450/45 mg is currently being tested. Conclusions: Combined ribociclib + binimetinib continues to show promising preliminary antitumor activity in patients with NRAS-mutant melanoma. Determination of RP2D and schedule is ongoing. Conflict of interest: Corporate-sponsored Research: Novartis.
3301 ORAL Two year estimate of overall survival in COMBI-v, a randomized, open-label, phase III study comparing the combination of dabrafenib (D) and trametinib (T) with vemurafenib (Vem) as first-line therapy in patients (pts) with unresectable or metastatic BRAF V600E/K mutation-positive cutaneous melanoma C. Robert1 , B. Karaszewska2 , J. Schachter3 , P. Rutkowski4 , A. Mackiewicz5 , D. Stroyakovskiy6 , M. Lichinitser7 , R. Dummer8 , F. Grange9 , L. Mortier10 , V. Chiarion-Sileni11 , K. Drucis12 , I. Krajsova13 , A. Hauschild14 , B. Mookerjee15 , J. Legos15 , D. Schadendorf16 . 1 Gustave-Roussy, Villejuif Paris, France; 2 Przychodnia Lekarska “Komed”, Konin, Poland; 3 Sheba Medical Center, Tel-Hashomer, Ramat-Gan, Israel; 4 Maria Sklodowska-Curie Memorial Cancer Center and Institute of Oncology, Warsaw, Poland; 5 Poznan University of Medical Sciences, Poznan, Poland; 6 Moscow City Oncology Hospital #62, Moscow, Russia; 7 N.N. Blokhin Russian Cancer Research Center, Moscow, Russia; 8 University Hospital Zurich, Zurich, Switzerland; 9 Centre ´ Reims, France; 10 CHRU Lille, Hospitalier Universitaire Robert Debre, University Lille II, Lille, France; 11 Veneto Oncology Institute, Padua, Italye; 12 Swissmed Centrum Zdrowia SA, Medical University, Gdansk, Poland; 13 VFN a 1LF UK Praha, Prague, Czech Republic; 14 University Hospital Schleswig-Holstein, Kiel, Germany; 15 GlaxoSmithKline, Collegeville, PA, USA; 16 University Hospital Essen, Essen, Germany Background: This Phase III study (NCT01597908) of dabrafenib (D) + trametinib (T) compared with vemurafenib (Vem) demonstrated a 31% reduction in the risk of death for D+T compared with Vem (HR = 0.69; 95% CI: 0.53–0.89; p = 0.005) in pts with BRAF V600E/K mutant, metastatic melanoma at the interim analysis (N Engl J Med 2015; 372: 30−9). The adjusted stopping boundary for efficacy (p < 0.0214) was crossed at the interim analysis and the study was stopped for efficacy by the Independent Data Monitoring Committee (IDMC). Rates of adverse events (AEs) were similar for both arms. There was a higher incidence of pyrexia and ejection fraction decrease with D+T, and a lower incidence of cutaneous malignancies, hyperproliferative events, and photosensitivity with D+T compared to Vem. Methods: Pts were randomized 1:1 to receive D (150 mg twice daily) + T (2 mg once daily) or Vem (960 mg twice daily) as first-line therapy. Eligible pts were 18 years, ECOG performance status 1, and had histologically confirmed unresectable stage IIIC or IV, BRAF V600E/K mutant cutaneous melanoma. The primary endpoint was OS; secondary endpoints were PFS, overall response rate (ORR), duration of response (DoR), and safety. Results: From June 2012 to October 2013, 1,645 pts were registered and 704 were randomized 1:1 to one of two treatment arms (352 to D+T, 352 to Vem). The updated (March 13th 2015) OS analysis demonstrated a statistically significant improvement in OS for D+T over Vem (HR = 0.66 [95% CI: 0.53–0.81; p < 0.001]) and median OS of 25.6 vs 18 months. The updated analysis reported a statistically significant improvement in PFS for D+T over Vem (HR = 0.61 [95% CI: 0.51–0.73], p < 0.001) and median PFS of 12.6 and 7.3 months, respectively. The 2-year estimate of OS and updated efficacy and safety results will be presented.
S664 Conclusions: Updated OS analysis confirmed improvement in OS favoring D+T over Vem with medians of 25.6 versus 18 months. Two-year OS rates and additional efficacy and safety analysis will be presented. Conflict of interest: Ownership: J Legos reported equity ownership with GSK. B Mookerjee reported equity ownership with GSK, Incyte Corporation, and AstraZeneca. Advisory Board: P Rutkowski participated in an Advisory Committee for Novartis, Roche, BMS, and MSD. R Dummer participated in an Ad Board with Roche, BMS, GSK, MSD, Novartis. V Chiarion-Sileni participated in an Advisory Committee for BMS, GSK, Roche, and Merck. I Krajsova´ participated in an Advisory Committee for BMS. Board of Directors: P Rutkowski was a member of the board of directors for Novartis, Roche, BMS, and MSD. V Chiarion-Sileni was a member of the board of directors for BMS, GSK, Roche, and Merck. I was a member of the board of directors for BMS. Corporatesponsored Research: M Lichinitser received research funding from GSK. R Dummer received research funding from Roche, BMS, GSK, MSD, Novartis. K Drucis received research funding from GSK. A Hauschild received research funding from Amgen, BMS, Celgene, Eisai, GSK, MelaSciences, Merck Serono, MSD/Merck, Novartis, Oncosec, Roche Pharma. Other Substantive Relationships: C Robert acted as a consultant for GSK, Novartis, Merck, BMS, Amgen, and Roche. P Rutkowski received honoraria from Novartis, GSK, Roche, Amgen, Pfizer, BMS, MSD, and Bayer and participated in a speakers bureau for Novartis and Pfizer. L Mortier reports personal fees from GSK, during the conduct of the study. A Hauschild acted as a consultant for Amgen, BMS, Celgene, Eisai, GSK, MedImmune, MelaSciences, Merck Serono, MSD/Merck, Novartis, Oncosec, and Roche and received honoraria from Amgen, BMS, Celgene, Eisai, GSK, MedImmune, MelaSciences, Merck Serono, MSD/Merck, Novartis, Oncosec, and Roche. B Mookerjee and J Legos are employees of GSK. D Schadendorf acted as a consultant and received honoraria from, and participated in a speakers bureau for GSK, Novartis, Roche, Amgen, BMS, Boehringer Ingelheim, and Merck/MSD. 3302 ORAL Safety and Activity of Combined Radiotherapy (RT) and Anti-PD-1 Antibodies (PD-1) in Patients (pts) with Metastatic Melanoma E. Liniker1 , B. Kong2 , A.M. Menzies1 , A. Cooper2 , S. Ramanujam1 , S. Lo3 , R.F. Kefford2 , G.B. Fogarty4 , A. Guminski1 , T.W. Wang5 , M.S. Carlino2 , A. Hong4 , G.V. Long1 . 1 Melanoma Institute Australia, Medical Oncology, Sydney, Australia; 2 Crown Princess Mary Cancer Centre, Westmead, Medical Oncology, Sydney, Australia; 3 Melanoma Institute Australia, Statistics, Sydney, Australia; 4 Melanoma Institute Australia, Radiation Oncology, Sydney, Australia; 5 Crown Princess Mary Cancer Centre, Westmead, Radiation Oncology, Sydney, Australia Background: Prior studies suggest that RT can induce an abscopal immune response that may be enhanced with the addition of immunotherapy such as ipilimumab (ipi). This effect is thought to be driven via the release of tumour antigens and subsequent immune recognition. We sought to review the clinical outcomes of pts receiving RT immediately prior to or during PD1 therapy. Materials and Methods: All pts receiving pembrolizumab or nivolumab for unresectable stage III/IV melanoma who had sequential (4 weeks prior to PD1 commencement) or concurrent RT were identified. RT and systemic treatment, clinical outcome and toxicity data was collected. Results: Of all pts treated with PD1 at Melanoma Institute Australia and Westmead Hospital, 39 had either sequential RT (n = 10, 26%), concurrent RT (n = 26, 67%), or both (n = 3, 8%). Median time to RT was 8.5 days after commencing PD1 (range −28 to 185). 34 (89%) pts received prior ipi (median 3 doses, mean interval last ipi to PD1 72 days). 16 pts had brain metastases (BM) at start of PD1 (median no. of BM 4), 21 (54%) had an elevated LDH, and 29 (74%) had M1c disease. 27 (69%) had RT to extracranial sites, 4 (10%) had stereotactic RT (SRS) to BM and 4 (10%) had whole brain RT (WBRT). 4 (10%) had a combination of these. Of 32 evaluable pts at data cut, 9 (28%) had overall RECIST partial response (PR), none had complete response (CR). 5 (16%) had stable disease (SD). A total of 82 metastases were irradiated; 25 were clinically or radiologically progressing on PD1 at RT start and could be assessed for lesional response by RECIST criteria. 7 of 25 (28%) had subsequent PR, 3 (12%) had CR, and 5 (20%) continued to progress. In pts with BM, median progression free survival (PFS) and overall survival (OS) were 2.5 months and 6.8 months respectively, while in pts without BM PFS was 4.1 months and OS 16.4 months. No excess RT toxicity was observed except: cerebral radionecrosis in one pt 3 months after SRS that responded to bevacizumab and steroids; potential delayed neurotoxicity in a single pt with multiple small asymptomatic BMs treated with a single dose of ipi closely followed by PD1 and concurrent WBRT (20Gy/5#); disproportionate cerebral oedema in a pt with rapidly
Abstracts progressive BMs treated with concurrent ipi, PD1 and WBRT. Irradiated and non-irradiated lesion-specific and site-specific (intracranial and extracranial) response rates will be examined, and updated survival analyses will be performed. Conclusions: These results suggest that RT and PD1 can be safely coadministered with no excess acute extracranial toxicity. The potential for neurotoxicity with cerebral RT requires further investigation. RT can be effective for local control of lesions progressing on PD1. Conflict of interest: Advisory Board: Richard F Kefford − Educational funds to institution BMS, Merck. Honoraria for Educational Symposia: Merck, BMS. Advisory Boards: Merck, BMS, Novartis, GSK, Roche, Amgen. Matteo S Carlino − Merck Advisory Board, BMS Advisory Board. Georgina V. Long − Amgen Advisory Board, BMS Advisory Board, GSK Advisory Board, Merck Advisory Board, Novartis Advisory Board, Provectus Advisory Board, Roche Advisory Board. Other Substantive Relationships: Adam Cooper − sponsorship (partial scholarship) for PhD research from Novogen. Sangeetha Ramanujam − travel and accommodation grants from AMGEN for San Antonio Breast Symposium in 2013.
3303 ORAL Efficacy and safety in key patient subgroups of nivolumab (NIVO) alone or combined with ipilimumab (IPI) versus IPI alone in treatment-na¨ıve patients with advanced melanoma (MEL) (CheckMate 067) J. Larkin1 , V. Chiarion-Sileni2 , R. Gonzalez3 , J.J. Grob4 , C.L. Cowey5 , C.D. Lao6 , J. Wagstaff7 , D. Hogg8 , A. Hill9 , M.S. Carlino10 , P. Wolter11 , C. Lebbe´ 12 , J. Schachter13 , L. Thomas14 , J.C. Hassel15 , P. Lorigan16 , D. Walker17 , J. Jiang18 , F.S. Hodi19 , J.D. Wolchok20 . 1 Royal Marsden Hospital, Medical Oncologist, London, United Kingdom; 2 IOV-IRCCS-Melanoma Oncology Unit, Melanoma Cancer Unit, Padova, Italy; 3 University of Colorado Cancer Center, Division of ˆ Medical Oncology, Aurora CO, USA; 4 Aix-Marseille University-Hopital de La Timone APHM, Department of Dermatology and Skin Cancers, 5 Marseille, France; Baylor Charles A. Sammons Cancer Center, Hematology/Medical Oncology, Dallas TX, USA; 6 University of Michigan, Medical Oncology, Ann Arbor MI, USA; 7 South West Wales Cancer Institute-Singleton Hospital, Oncology Clinical Trials Unit, Swansea, United Kingdom; 8 Princess Margaret Hospital-University of Toronto, Clinical Studies Resource Center, Toronto ON, Canada; 9 Tasman Oncology Research, Department of Health, South Gold Coast QLD, Australia; 10 Melanoma Institute Australia and the University of Sydney, Medical Oncology, Sydney NSW, Australia; 11 UZ Leuven, Medical ˆ Oncology, Leuven, Belgium; 12 Hopital Saint-Louis University Paris Diderot, Department of Dermatology, Paris, France; 13 Oncology Institute, Ella Institute for the Treatment and Research of Melanoma and Skin Cancer at the Sheba Medical Center, Tel Hashomer, Israel; 14 Centre Hospitalier ´ Lyon Sud, Department of Dermatology, Pierre-Benite, France; 15 German Cancer Research Centre University Hospital, Department of Dermatology and National Center for Tumor Diseases, Heidelberg, Germany; 16 The Christie NHS Foundation Trust, Medical Oncology, Manchester, United Kingdom; 17 Bristol-Myers Squibb, Global Clinical Research, Princeton NJ, USA; 18 Bristol-Myers Squibb, Global Biometric Sciences, Hopewell NJ, USA; 19 Dana-Farber Cancer Institute, Department of Medicine-Harvard Medical School, Boston MA, USA; 20 Memorial Sloan Kettering Cancer Center and Weill Cornell Medical College, Melanoma and Immunotherapeutics Services, New York NY, USA Background: The CheckMate 067 phase III study compared NIVO (a PD-1 checkpoint inhibitor) or NIVO combined with IPI (a CTLA-4 checkpoint inhibitor) to IPI alone in patients (pts) with MEL. The combination of NIVO and IPI significantly improved progression-free survival (PFS) and objective response rate (ORR) versus IPI alone. Here, we report the results of subgroup analyses across the 3 treatment groups in this trial, including pts with poor prognostic factors. Material and Methods: Treatment-na¨ıve pts with MEL (N = 945) were randomized 1:1:1 to receive NIVO (3 mg/kg Q2W) + placebo (PBO), or NIVO + IPI (1 mg/kg + 3 mg/kg Q3W X 4) followed by NIVO 3 mg/kg Q2W, or to IPI (3 mg/kg Q3W X 4) + PBO until disease progression or unacceptable toxicity. PFS, a co-primary endpoint, was evaluated in predefined subgroups, including M stage of disease, serum lactate dehydrogenase (LDH) levels and BRAF mutation status. Results: Baseline characteristics of the pts were balanced across the 3 treatment arms, with 58% having M1c stage of disease, 36% having elevated LDH levels and 32% a BRAF V600 mutation. In the total population, median PFS was 11.5 months for NIVO + IPI versus 2.9 months for IPI alone (hazard ratio [HR] vs IPI, 0.42; P < 0.00001), and was 6.9 months for NIVO alone (HR vs IPI, 0.57; P < 0.00001). Numerically longer
Abstracts
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PFS was observed in the combination group versus NIVO or IPI alone in all predefined subgroups of pts (Table). The incidence of drug-related grade 3−4 adverse events was 55.0%, 16.3% and 27.3% in the NIVO + IPI, NIVO and IPI groups, respectively. Across pt subgroups, the safety profile was consistent with that observed in the overall safety population (eg, in pts 75 yr, 48%, 21% and 36% in the NIVO + IPI, NIVO and IPI groups, respectively, experienced drug-related grade 3−4 adverse events). Conclusions: In pts with treatment-na¨ıve MEL, NIVO + IPI and NIVO alone significantly improved PFS across predefined subgroups, including pts with poor prognostic factors. The safety profile of the combination was manageable across subgroups of pts.
Total population BRAF Wild-type Mutant M stage M0/M1a/M1b M1c Baseline LDH ULN >ULN Age (yr) <65 65 and <75 75
N N
Median PFS (95% CI) NIVO NIVO + IPI
IPI
945
6.9 (4.3−9.5)
11.5 (8.9–16.7)
2.9 (2.8−3.4)
645 300
7.9 (4.9–12.7) 5.6 (2.8−9.5)
11.2 (8.3−NR) 11.7 (8.0−NR)
2.8 (2.8−3.1) 4.0 (2.8−5.5)
386 559
9.3 (5.6−NR) 5.4 (2.8−8.9)
15.5 (11.2−NR) 8.5 (5.5–12.4)
4.2 (3.0−5.5) 2.8 (2.7−2.8)
589 341
10.2 (6.9–14.3) 2.8 (2.6−4.0)
14.0 (11.3−NR) 4.2 (2.8−9.3)
4.0 (3.0−5.2) 2.6 (2.6−2.8)
565 262 118
5.5 (3.0−8.3) 12.7 (6.7−NR) 5.3 (2.6−NR)
11.7 (7.0−NR) 11.1 (8.3–14.0) NR (4.4−NR)
2.8 (2.8−3.1) 2.9 (2.7−3.9) 4.0 (2.8−6.9)
NR, not reached; ULN, upper limit of normal.
Conflict of interest: Advisory Board: V. Chiarion-Sileni has had an advisory board/consulting role for Roche, Bristol-Myers Squibb, GlaxoSmithKline, and MSD. R. Gonzalez has had an advisory board/ consulting role with Roche and Piramal. J.J. Grob has had an advisory board/consulting role for Bristol-Myers Squibb, GlaxoSmithKline, Novartis, Amgen, Merck, and Roche. M.S. Carlino has had an advisory board/ consulting role for Bristol-Myers Squibb. P. Wolter has had an advisory board/consulting role for GlaxoSmithKline and Bristol-Myers Squibb. C. Lebbe´ has had an advisory board/consulting role for Bristol-Myers Squibb, MSD, Roche, GlaxoSmithKline, and Novartis. J.C. Hassel has had an advisory board/consulting role for Amgen and GlaxoSmithKline. P. Lorigan has had an advisory board/consulting role for Merck and Bristol-Myers Squibb. Corporate-sponsored Research: J. Larkin’s institution has received research funding from Pfizer, Bristol-Myers Squibb, Novartis, and MSD. R. Gonzalez’s institution has received research funding from GlaxoSmithKline, Roche, Genentech, Bristol-Myers Squibb, Merck, and Castle. J.J. Grob has received research funding from Roche and Bristol-Myers Squibb. C.L. Cowey has received research funding from Bristol-Myers Squibb, Merck, Genentech, Roche, and EMD Serono. P. Wolter has received research funding from GlaxoSmithKline, Pfizer, and Novartis. F.S. Hodi’s institution has received clinical trial support from Bristol-Myers Squibb, Merck, and Genentech. and he has received personal fees from Merck and Novartis. Other Substantive Relationships: V. Chiarion-Sileni has participated in speakers’ bureau for Roche, Bristol-Myers Squibb, and GlaxoSmithKline. and has received travel reimbursement from Roche, Bristol-Myers Squibb, GlaxoSmithKline, and MSD. R. Gonzalez has received honoraria from Bristol-Myers Squibb, Roche/Genentech, GlaxoSmithKline, Castle, and Amgen. J.J. Grob has participated in speakers’ bureau for GlaxoSmithKline, Roche, and Bristol-Myers Squibb. and has received travel reimbursement from Roche. C.L Cowey has employment and stock ownership with Texas Oncology, PA. has leadership with US Oncology-McKesson Specialty Health. has received honoraria from Novartis, Castle Biosciences, Celgene, Bristol-Myers Squibb, and Merck. has participated in speakers’ bureau for Bristol-Myers Squibb, and Merck. C.D. Lao has nothing to disclose. J. Wagstaff’s institution has received consulting fees from Bristol-Myers Squibb. A. Hill has employment from Tasman Oncology/Tasman Oncology Research. and has received travel reimbursement from Bristol-Myers Squibb. M.S. Carlino has received honoraria from Bristol-Myers Squibb. L. Thomas’ institution has received honoraria while he was PI at my center for the clinical trial reported herein. J.C. Hassel has received honoraria from Bristol-Myers Squibb, GlaxoSmithKline, MSD, and Amgen. has participated in speakers’ bureau for Bristol-Myers Squibb, GlaxoSmithKline, Roche, MSD, and Amgen. and has received travel reimbursement from Amgen and Bristol-Myers Squibb. P. Lorigan has received travel reimbursement from Merck and Bristol-Myers Squibb. F.S. Hodi has a patent Methods for treating MICA-related disorders with royalties paid, a patent Therapeutic Peptides pending, and a patent Tumor Antigens and Uses Thereof pending. D. Hogg, J. Schachter, D. Walker and J. Jiang have nothing to disclose.
3304 ORAL Metabolic activity in metastatic melanoma after long-term treatment with anti-PD-1 antibodies B. Kong1 , C. Saunders2,3,4 , E. Liniker5 , S. Ramanujam5 , A. Guminski4,5,6,7 , R. Scolyer4,5,8 , R. Kefford3,5 , A. Menzies4,5,6,7 , G. Long4,5,7 , M. Carlino1,4,5 . 1 Crown Princess Mary Cancer Centre, Medical Oncology, Sydney, Australia; 2 Westmead Hospital, Nuclear Medicine, Sydney, Australia; 3 Macquarie University, School of Advanced Medicine, Sydney, Australia; 4 University of Sydney, Medicine, Sydney, Australia; 5 Melanoma Institute Australia, Medical Oncology, Sydney, Australia; 6 Royal North Shore Hospital, Medical Oncology, Sydney, Australia; 7 Mater Hospital, Medical Oncology, Sydney, Australia; 8 Royal Prince Alfred Hospital, Anatomical Pathology, Sydney, Australia Background: Patients who receive anti-PD-1 antibodies for metastatic melanoma often have durable responses associated with radiological CR/PR/SD, however the metabolic activity and tumour viability of long term responders remains unknown. Materials and Methods: 18-F Fluorodeoxyglucose positron emission tomography CT (FDG-PET) scans were performed on patients treated with nivolumab or pembrolizumab for greater than twelve months on phase I-III clinical trials. Best overall radiological response (ORR) and response at time of PET scanning was determined using standard immune related response criteria (irRC). The presence of FDG-PET metabolic activity was classified by the visual inspection method. The metabolic activity of individual lesions identified on CT scans was subsequently characterised as PET positive or negative. Unexpected PET positive foci were included in the lesion-specific analysis even if not visible on prior CT. Biopsy or surgery was performed where clinically indicated to investigate the cause of unexpected or atypical lesions. Results: 27 patients underwent PET scans at a median of 15.2 months after starting treatment (Range 9.5–35.0 months). Best ORR was CR in 9 patients (33%), PR in 11 (41%), SD in 6 (22%) and PD in 1 (4%). At the time of PET scanning, 8 (29.6%) patients were in complete CT response (CR), 8 (29.6%) partial response (PR), 4 (14.8%) stable disease (SD) and 7 (25.9%) progressive disease (PD). A total of 62 individual lesions were identified on the CT scans prior to PET scanning, of which 34 (55%) were PET positive and 28 (45%) were PET negative. A further five PET positive lesions were identified which were not noted on CT. In patients who had not progressed via irRC (CR/PR/SD), 63% of their lesions were negative by PET. In contrast, in patients with disease progression (PD), 14% of their lesions negative by PET. Overall irRC response at time of PET
PET negative patients
PET positive patients
Biopsy of unexpected PET positive lesions
CR PR SD PD
6 4 2 0
2 4 2 7
2 1 1 1
lymphocytic infiltrate; 1 granuloma. melanoma melanoma granuloma; 3 melanoma
Six of eight (75%) CR patients had negative PET scans. Two of eight (25%) CR patients had PET positive scans, however biopsies excluded melanoma in both cases (lymphocytic infiltrate, granuloma). Four of 8 (50%) PR patients had no PET positive lesions. Conclusions: In patients with prolonged response to anti-PD1 therapy and residual disease on CT the majority of disease is metabolically inactive. In patients with a radiological CR, PET may be no more sensitive than CT in detecting recurrence. False positive results on PET may be due to treatment related granulomatous reactions, and biopsies of unexpected or atypical lesions should be considered to confirm or exclude disease progression. Conflict of interest: Ownership: Nil. Advisory Board: Amgen, BMS, GSK, Merck, Novartis, Provectus, Roche. Board of Directors: Nil. Corporatesponsored Research: Nil. Other Substantive Relationships: Honoraria paid by BMS, GSK, Merck, Provectus, Roche.
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Abstracts
3305 ORAL PD1 inhibition-induced changes in melanoma and its associated immune infiltrate R.E. Vilain1,2,3 , H. Kakavand1,2 , A.M. Menzies1,2 , J. Madore1,2 , J. Wilmott1,2 , R. Dobney1,2 , V. Jakrot1,2 , A.J. Cooper4 , B. Kong5 , S. Lo1,2 , E. Liniker1 , R.P. Saw1,2 , J.F. Thompson1,2 , R. Kefford1,2,5 , M.S. Carlino1,5,2 , G.V. Long1,2 , R.A. Scolyer1,2,3 . 1 Melanoma Institute Australia, Sydney, NSW, Australia; 2 The Sydney University, Sydney Medical School, Sydney, NSW, Australia; 3 Royal Prince Alfred Hospital, Tissue Pathology and Diagnostic Oncology, Sydney, Australia; 4 Liverpool Hospital, Department of Medical Oncology, Liverpool, Australia; 5 Westmead Hospital, Department of Medical Oncology, Westmead, Australia Background: The immune checkpoint inhibitors pembroluzimab and nivolumab disrupt PD-L1/cytotoxic T-cell PD1 signalling and improve survival in metastatic melanoma patients. To date, little is known about changes in tumoral PD-L1 expression and tumor-associated immune cell flux in melanoma patients undergoing these treatments. Materials and Methods: 49 tumor biopsies from 24 unresectable AJCC Stage III/IV metastatic melanoma patients receiving pembrolizumab/ nivolumab were analyzed. Tumor biopsies were collected prior to (PRE, n = 21) and within two months of commencing treatment (EDT, n = 21) and again on disease progression (PROG, n = 7). Patients exhibiting stable disease (n = 9), partial (n = 6) or complete (n = 1) regression on their best response on RECIST or iRC criteria were deemed responders. Response status was correlated with a histomorphological and immunohistochemical analysis. Results: PRE intra-tumoral and peri-tumoral density of PD1+ T-cells was 8.1-fold higher (p = 0.0142) and 6.8-fold higher (p = 0.0098) in responders and directly correlated with the degree of tumor shrinkage on radiology (r=-0.356, p = 0.0090 and r=-0.442, p = 0.0035, respectively). EDT biopsies revealed a significant influx of intra-tumoral CD3+, CD8+ and CD68+ macrophages in the responders, but not in non-responders. At EDT, the distribution of tumoral and macrophage PD-L1 expression was higher in responders (p = 0.0554 and p = 0.0379, respectively). PD-L1 expression was universally present in the tumor and macrophage cell components at PROG. A trend for an increase in intra-tumoral and peri-tumoral macrophage density at PROG was observed. Conclusions: The higher numbers of PD1+ T-cells in the PRE biopsies of responders suggests the active suppression of an engaged immune system, which is disinhibited by anti-PD1 therapies. Furthermore, it may also serve as a biomarker of treatment response. The increased PD-L1 expression in EDT biopsies of responders likely reflects disengagement of the PD-L1/PD1 axis, reactivation of PD1+ T-cells and increased interferong production. On the acquisition of resistance to PD1 inhibition, the lack of changes in PD-L1 expression or T-cell infiltrates suggests other mechanisms are involved in immune escape. Conflict of interest: Advisory Board: RK is a consultant advisor to Merck, BMS, GSK, Novartis and Roche as well as Honoraria from Merck, BMS, Roche and GSK and an unrestricted Educational Grant from BMS. MC is a consultant advisor to Merck and BMS. GL is a consultant advisor to Amgen, BMS, GSK, Novartis, Roche, and has received Honoraria.
Poster Session (Sunday, 27 September) Melanoma and Skin Cancer 3306 Immunological microenvironment of basal cell carcinoma
POSTER
Y. Przhedetsky1 , E. Zlatnik2 , N. Zakharova1 , E. Sharay1 , G. Zakora2 , A. Bakhtin2 . 1 Rostov Research Institute of Oncology, Department of Reconstructive and Plastic Surgery, Rostov-Don, Russian Federation; 2 Rostov Research Institute of Oncology, Department of Immunology, Rostov-Don, Russian Federation Background: Though basal cell carcinoma (BCC) is not metastatic, its tumor growth has become more aggressive in recent years. As it commonly appears on the face, surgical and radiotherapy options are limited. Local immunity in different types of BCC is of special scientific and clinical interest. The purpose of the study was to analyze the local immunity factors in BCC microenvironment in different tumor spread and patients’ parameters. Material and Methods: Tumor removal with subsequent plastic reconstruction for the postoperative defect was performed in 43 patients (24 women and 19 men aged 21−86) with primary (29) and recurrent (14) BCC from T1N0M0 to T4N0M0. Tumor fragments were homogenized,
lymphocyte populations and subpopulations were determined using BD FACSCanto II Flow Cytometer and a panel of antibodies to T-, B- and NKcells (CD45+, CD3, CD4, CD8, CD19, CD16/56) and levels of cytokines IL-1b, IL-6, IL-8 and TNF-a were defined by ELISA. Healthy skin tissue removed during plastic surgery served as the control. Results: Content of anti-inflammatory cytokines in BCC tissue exceeded the levels in healthy skin which was statistically significantly for IL-1b (50.0±6.5 against 17.2±7.5 pg/g of protein) and IL-8 (48.8±8.5 against 15.7±6.3 pg/g of protein). NK-cell level in tumor was lower (2.1±0.6 against 8.85±2.7%) and level of B-lymphocytes − higher (5.1±1.5 against 0.8±0.4% respectively) (p < 0.05 for all cases). Levels of IL-1b, IL-8 and NK-cells were higher in tumors of patients under 50 years old in comparison with the older patients. Content of CD3+CD4+ lymphocytes and IL-1b was higher in solid tumors than in infiltrative and superficial ones, and recurrent tumors differed from infiltrative ones in the lower TNF-a level (1.44±0.3 and 2.9±0.7 pg/g of protein respectively, p < 0.05) which was at the same time higher than in healthy tissue. The minimal level of TNF-a was observed in T4N0M0 tumors in comparison with T1-T3 ones. Conclusions: A number of immunological characteristics varying in different stages and variants of tumor and patients’ age were observed in BCC microenvironment; the common feature of all tumor variants was the high content of IL-1b and IL-8 cytokines in tissue of tumor which can assist its growth. No conflict of interest. 3307 POSTER An immunoglobulin VH CDR-3-derived peptide attenuates Hsp90 activity, binds to an adhesion GPCR and promotes hyperadherence, motility arrest and anti-melanoma metastatic activity N. Girola1 , A.L. Matsuo1 , C.R. Figueiredo1 , M.H. Massaoka1 , D.C. Arruda1 , C.F. Farias1 , R.A. Azevedo2 , L.R. Travassos1,3 . 1 Federal ˜ Paulo, Experimental Oncology Unit UNONEX, Sao ˜ Paulo, University of Sao Brazil; 2 Butantan Institute, Department of Biochemistry and Biophysics 3 ˜ Paulo, Brazil; Recepta Biopharma, Sao ˜ Paulo, SP, Brazil Laboratory, Sao Background: Malignant melanoma is a lethal skin cancer largely resistant to current therapies. Synthetic peptides are promising candidates for tumor therapy and currently, small peptides corresponding to complementaritydetermining regions (CDRs) from different immunoglobulins have been shown to induce anti-infective and antitumor activities regardless of the specificity of the original monoclonal antibody (mAb). The present work focused on the antitumor effects of a peptide (Rb9) derived from VH CDR 3 (H3) of an anti-NaPi3b mAb, using as target cells the B16F10-Nex2 murine melanoma lineage. The peptide effects on tumor cell adhesion, migration, invasion and metastasis in a syngeneic model and the cell signaling pathways were investigated. Materials and Methods: Tumor cell migration/invasion was assessed by the wound-healing and Matrigel® assays. Rb9 cell signaling in B16F10Nex2 cells was assessed by Western blotting, cAMP and calcium release assays. Rb9 binding to Hsp90 and the inhibition of its activity were determined by ELISA, using recombinant Hsp90 protein, and by the citrate synthase aggregation assay, respectively. The peptide also bound to the melanoma cell surface, as seen by confocal microscopy. Hsp90 and GPR124 internal peptides were used as Rb9 binding substrates. In vivo assays were performed with 6−8 weeks-old C57Bl/6 mice by intravenous challenge with B16F10-Nex2 melanoma cells. Results: Hsp90 and GPR124 are expressed on melanoma cells and Rb9, but not the Cys-less Rb10A1 control, bound to Hsp90, two Hsp-90 C-terminal peptides, and to a GPR124-GAIN domain peptide. Effects were: 1) inhibition of HSP90 chaperoning activity, down-activation of FAK, Src and Rac1 affecting cell migration; 2) GPR124-G-protein activation, induction of cAMP and Ca++, and PKA/VASP signaling; 3) Inhibition of murine melanoma lung metastasis in syngeneic mice. Altogether, the peptide caused tumor cell hyperadherence, motility arrest, invasion inhibition and anti-metastatic effects. Conclusion: The VH CDR-3-derived peptide (Rb9) binds to melanoma cell surface components modulating signaling pathways that lead to antitumor activity involving hyperadherence and inhibition of migration/ invasion. These effects warrant further development of a drug-peptide against malignant melanoma. Supported by FAPESP 2010–51423−0 No conflict of interest.