• Clinical and immunological responses in metastatic melanoma patients vaccinated with a high-dose poly-epitope vaccine.

      Dangoor, A; Lorigan, Paul C; Keilholz, U; Schadendorf, D; Harris, A; Ottensmeier, C; Smyth, J; Hoffmann, K; Anderson, R; Cripps, M; et al. (2010-06)
      BACKGROUND: Safety and cellular immunogenicity of rising doses and varying regimens of a poly-epitope vaccine were evaluated in advanced metastatic melanoma. The vaccine comprised plasmid DNA and recombinant modified vaccinia virus Ankara (MVA) both expressing a string (Mel3) of seven HLA.A2/A1 epitopes from five melanoma antigens. METHODS: Forty-one HLA-A2 positive patients with stage III/IV melanoma were enrolled. Patient groups received one or two doses of DNA.Mel3 followed by escalating doses of MVA.Mel3. Immunisations then continued eight weekly in the absence of disease progression. Epitope-specific CD8+ T cell responses were evaluated using ex-vivo tetramer and IFN-gamma ELISPOT assays. Safety and clinical responses were monitored. RESULTS: Prime-boost DNA/MVA induced Melan-A-specific CD8+ T cell responses in 22/31 (71%) patients detected by tetramer assay. ELISPOT detected a response to at least one epitope in 10/31 (32%) patients. T cell responder rates were <50% with low-dose DNA/MVA, or MVA alone, rising to 91% with high-dose DNA/MVA. Among eight patients showing evidence of clinical benefit-one PR (24 months+), five SD (5 months+) and two mixed responses-seven had associated immune responses. Melan-A-tetramer+ immunity was associated with a median 8-week increase in time-to-progression (P = 0.037) and 71 week increase in survival (P = 0.0002) compared to non-immunity. High-dose vaccine was well tolerated. The only significant toxicities were flu-like symptoms and injection-site reactions. CONCLUSIONS: DNA.Mel3 and MVA.Mel3 in a prime-boost protocol generated high rates of immune response to melanoma antigen epitopes. The treatment was well tolerated and the correlation of immune responses with patient outcomes encourages further investigation.
    • Detection of BRAF mutations in the tumour and serum of patients enrolled in the AZD6244 (ARRY-142886) advanced melanoma phase II study.

      Board, Ruth E; Ellison, G; Orr, M C M; Kemsley, K R; McWalter, G; Blockley, L Y; Dearden, S P; Morris, C; Ranson, Malcolm R; Cantarini, M V; et al. (2009-11-17)
      BACKGROUND: This study investigated the potential clinical utility of circulating free DNA (cfDNA) as a source of BRAF mutation detection in patients enrolled into a phase II study of AZD6244, a specific MEK1/2 inhibitor, in patients with advanced melanoma. METHODS: BRAF mutations were detected using Amplification Refractory Mutation System allele-specific PCR. BRAF mutation status was assessed in serum-derived cfDNA from 126 patients enrolled into the study and from 94 matched tumour samples. RESULTS: Of 94 tumour samples, 45 (47.9%) were found to be BRAF mutation positive (BRAF+). Serum-derived cfDNA was BRAF+ in 33 of 126 (26.2%) samples, including in five samples for which tumour data were unavailable. Of BRAF+ tumours, 25 of 45 (55.6%) were BRAF+ in cfDNA. In three cases in which the tumour was negative, cfDNA was BRAF+. Progression-free survival (PFS) of patients with BRAF+ tumour and cfDNA was not significantly different compared with tumour BRAF+ but cfDNA BRAF-negative patients, indicating that cfDNA BRAF detection is not associated with poorer prognosis on PFS in stage III/IV advanced melanoma. CONCLUSIONS: These data demonstrate the feasibility of BRAF mutation detection in cfDNA of patients with advanced melanoma. Future studies should aim to incorporate BRAF mutation testing in cfDNA to further validate this biomarker for patient selection.
    • Multiplexed assays for detection of mutations in PIK3CA.

      Board, Ruth E; Thelwell, Nicola J; Ravetto, Paul F; Little, Stephen; Ranson, Malcolm R; Dive, Caroline; Hughes, Andrew; Whitcombe, David; Discovery Medicine, AstraZeneca Pharmaceuticals, Macclesfield, UK. ruth.board@astrazeneca.com (2008-04)
      BACKGROUND: Mutations in the PIK3CA gene (phosphoinositide-3-kinase, catalytic, alpha polypeptide) have recently been described in a number of cancers, and their detection is currently limited because of the low sensitivity of conventional sequencing techniques. METHODS: We combined Amplification Refractory Mutation System (ARMS; AstraZeneca) allele-specific PCR and Scorpions (DxS) to develop assays for tumor-borne PIK3CA mutations and used real-time PCR to develop high-throughput multiplexed assays for the most commonly reported PIK3CA mutants (H1047L, H1047R, E542K, E545K). RESULTS: These assays were more sensitive than sequencing and could detect 5 copies of mutant DNA in proportions as low as 0.1% of the total DNA. We assayed DNA extracted from human tumors and detected PIK3CA mutation frequencies of 10.2% in colorectal cancer, 38.7% in breast cancer, 1.9% in lung cancer, and 2.9% in melanoma. In contrast, sequencing detected only 53% of the mutations detected by our assay. CONCLUSIONS: Multiplexed assays, which can easily be applied to clinical samples, have been developed for the detection of PIK3CA mutations.
    • O(6)-methylguanine-DNA methyltransferase depletion and DNA damage in patients with melanoma treated with temozolomide alone or with lomeguatrib.

      Watson, Amanda J; Middleton, Mark R; McGown, Gail; Thorncroft, Mary R; Ranson, Malcolm R; Hersey, Peter; McArthur, Grant A; Davis, Ian D; Thomson, D; Beith, Jane; et al. (2009-04-21)
      We evaluated the pharmacodynamic effects of the O(6)-methylguanine-DNA methyltransferase (MGMT) inactivator lomeguatrib (LM) on patients with melanoma in two clinical trials. Patients received temozolomide (TMZ) for 5 days either alone or with LM for 5, 10 or 14 days. Peripheral blood mononuclear cells (PBMCs) were isolated before treatment and during cycle 1. Where available, tumour biopsies were obtained after the last drug dose in cycle 1. Samples were assayed for MGMT activity, total MGMT protein, and O(6)-methylguanine (O(6)-meG) and N7-methylguanine levels in DNA. MGMT was completely inactivated in PBMC from patients receiving LM, but detectable in those on TMZ alone. Tumours biopsied on the last day of treatment showed complete inactivation of MGMT but there was recovery of activity in tumours sampled later. Significantly more O(6)-meG was present in the PBMC DNA of LM/TMZ patients than those on TMZ alone. LM/TMZ leads to greater MGMT inactivation, and higher levels of O(6)-meG than TMZ alone. Early recovery of MGMT activity in tumours suggested that more protracted dosing with LM is required. Extended dosing of LM completely inactivated PBMC MGMT, and resulted in persistent levels of O(6)-meG in PBMC DNA during treatment.
    • A phase I study of the safety and tolerability of olaparib (AZD2281, KU0059436) and dacarbazine in patients with advanced solid tumours.

      Khan, O A; Gore, M; Lorigan, Paul C; Stone, J; Greystoke, Alastair; Burke, W; Carmichael, J; Watson, Amanda J; McGown, Gail; Thorncroft, Mary R; et al. (2011-03-01)
      Poly adenosine diphosphate (ADP)-ribose polymerase (PARP) is essential in cellular processing of DNA damage via the base excision repair pathway (BER). The PARP inhibition can be directly cytotoxic to tumour cells and augments the anti-tumour effects of DNA-damaging agents. This study evaluated the optimally tolerated dose of olaparib (4-(3--4-fluorophenyl) methyl-1(2H)-one; AZD2281, KU0059436), a potent PARP inhibitor, with dacarbazine and assessed safety, toxicity, clinical pharmacokinetics and efficacy of combination treatment.
    • Phase II trial of tremelimumab (CP-675,206) in patients with advanced refractory or relapsed melanoma.

      Kirkwood, John M; Lorigan, Paul C; Hersey, Peter; Hauschild, Axel; Robert, Caroline; McDermott, David F; Marshall, Margaret A; Gomez-Navarro, Jesus; Liang, Jane Q; Bulanhagui, Cecile A; et al. (2010-02-01)
      PURPOSE: This phase II study assessed the antitumor activity of tremelimumab, a fully human, anti-CTL-associated antigen 4 monoclonal antibody, in patients with melanoma. EXPERIMENTAL DESIGN: Patients with refractory/relapsed melanoma received 15 mg/kg tremelimumab every 90 days. After 4 doses, patients with tumor response or stable disease were eligible to receive < or =4 additional doses. Primary endpoint was best overall tumor response assessed by an independent endpoint review committee, and secondary endpoints included duration of response, overall survival, progression-free survival, and safety. RESULTS: Of 251 patients enrolled, 246 (241 response-evaluable) received tremelimumab. Objective response rate was 6.6% (16 partial responses); duration of response was 8.9 to 29.8 months. Eight (50%) objective responses occurred in patients with stage IV M(1c) disease, and 11 (69%) were ongoing at last tumor assessment. Eight (3.3%) patients achieved responses in target lesions (Response Evaluation Criteria in Solid Tumors) despite progressive disease within the first cycle. All 8 survived for >20 months; 5 (63%) remained alive. Clinical benefit rate (overall response + stable disease) was 21% (16 partial responses and 35 stable disease), and median overall survival was 10.0 months. Progression-free survival at 6 months was 15%, and survival was 40.3% at 12 months and 22% at 24 months. Common treatment-related adverse events were generally mild to moderate, and grade 3/4 adverse events included diarrhea (n = 28, 11%), fatigue (n = 6, 2%), and colitis (n = 9, 4%). There were 2 (0.8%) treatment-related deaths. CONCLUSIONS: Tremelimumab showed an objective response rate of 6.6%, with all responses being durable > or =170 days since enrollment, suggesting a potential role for tremelimumab in melanoma.
    • Predicting the myelotoxicity of chemotherapy: the use of pretreatment O6-methylguanine-DNA methyltransferase determination in peripheral blood mononuclear cells.

      Sabharwal, A; Waters, R; Danson, Sarah; Clamp, Andrew R; Lorigan, Paul C; Thatcher, Nick; Margison, Geoffrey P; Middleton, Mark R; Department of Medical Oncology, University of Oxford, Oxford, UK. (2011-12-21)
      To assess the value of pretreatment O-methylguanine-DNA methyltransferase (MGMT) expression in peripheral blood mononuclear cells (PBMCs) in predicting haematological toxicity with O-alkylating agent chemotherapy, we explored this relationship retrospectively in melanoma patients. Ninety-three patients treated with temozolomide or dacarbazine in four clinical trials were assessed, and a model of the interaction between MGMT expression and haematological toxicity was constructed. Nadir white-cell and platelet counts were related to, and hence could be predicted from, pretreatment MGMT. Leucopenia and thrombocytopenia were more prevalent amongst patients with low pretreatment MGMT, according to the highest grades of toxicity experienced and/or the dose intensity patients could sustain. Addition of interferon to chemotherapy or compression of the temozolomide schedule increased the toxicity. The model also predicts significant myelotoxicity where PBMC MGMT is inactivated, consistent with the experience in the clinic with lomeguatrib and O-benzylguanine. Determination of MGMT in PBMC can identify patients at greatest risk of toxicity or who are suitable for dose intensification.
    • Revised UK guidelines for the management of cutaneous melanoma 2010.

      Marsden, J R; Newton-Bishop, J; Burrows, L; Cook, M; Corrie, P G; Cox, N H; Gore, M E; Lorigan, Paul C; Mackie, R; Nathan, P; et al. (2010-09)
      These guidelines for the management of cutaneous melanoma present an evidence-based guidance for treatment, with identification of the strength of evidence available at the time of preparation of the guidelines, and a brief overview of epidemiology, diagnosis, investigation, and follow-up.
    • Sorafenib and dacarbazine as first-line therapy for advanced melanoma: phase I and open-label phase II studies.

      Eisen, T; Marais, R; Affolter, A; Lorigan, Paul C; Robert, C; Corrie, P; Ottensmeier, C; Chevreau, C; Chao, D; Nathan, P D; et al. (2011-07-26)
      The safety of oral sorafenib up to a maximum protocol-specified dose combined with dacarbazine in patients with metastatic, histologically confirmed melanoma was investigated in a phase I dose-escalation study and the activity of the combination was explored in an open-label phase II study.
    • Sorafenib and dacarbazine as first-line therapy for advanced melanoma: phase I and open-label phase II studies.

      Eisen, T; Marais, R; Affolter, A; Lorigan, Paul C; Robert, C; Corrie, P; Ottensmeier, C; Chevreau, C; Chao, D; Nathan, P D; et al. (2011-07-26)
      The safety of oral sorafenib up to a maximum protocol-specified dose combined with dacarbazine in patients with metastatic, histologically confirmed melanoma was investigated in a phase I dose-escalation study and the activity of the combination was explored in an open-label phase II study.
    • Systemic therapy for metastatic malignant melanoma--from deeply disappointing to bright future?

      Lorigan, Paul C; Eisen, Tim; Hauschild, Axel; CRUK Department of Medical Oncology, Christie Hospital NHS Trust, Wilmslow Road, Manchester, UK. paul.lorigan@manchester.ac.uk (2008-05)
      The last decade has seen a considerable improvement in the understanding of the biology of melanoma. Advances have come in the understanding of the importance of critical oncogenes and tumour suppressor genes, epigenetic phenomena, signalling pathways, drug resistance mechanisms, the pivotal role of the local immune system, and the importance of cell-cell and cell-matrix interactions. Many of these pathways and interactions include potentially 'drugable' targets. These developments have allowed the identification and/or design of a range of new, targeted therapies. Evaluation of these new drugs has brought a whole new series of challenges. These include identification of appropriate pre-clinical models, overcoming the redundancy in-built in complex biological systems, identification of appropriate molecular and clinical endpoints to show that the drug is hitting the target, how to combine treatments, and new toxicities. For the first time, there is the possibility of personalized treatment for melanoma patients, based on individual host and tumour characteristics. This paper discusses the range of new drugs and targets have been identified, the outcome of clinical trials, and the directions for future advances.