Phase II clinical trial with a second generation, GM-CSF encoding, oncolytic herpesvirus in unresectable metastatic melanoma

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Background: OncoVEXGM-CSF is a an oncolytic HSV, encoding GM-CSF . We recently completed a phase II trial involving 50 advanced melanoma patients (stage IIIc and IV) with at least one injection accessible lesion, including by ultrasound. Methods: Patients received a single IT injection of 106 pfu/ml apportioned between 10 or less injectable tumors, followed 3 wks later by 24 or less sequential injections of 108 pfu/ml every 2 wks until clinically significant disease progression, or overall or injectable lesion complete response. Response (RECIST modified to allow progression before response and biopsy of residual masses) and survival were monitored. Results: All 50 pts have been enrolled and are evaluable (Stage IIIc, n=10; IV M1a, n=16; IV M1b, n=4; IV M1c, n=20). A median of 6 injections were administered. Adverse effects were limited and generally involved transient flu-like symptoms. Both injected and uninjected regional and distant disease demonstrated response including clearly documented responses at uninjected visceral sites. The overall response rate was 26% (8 CR, 5 PR); 10 responses have been maintained for >6 months and 2 are ongoing at <6months, the longest currently being at 35 months from first dose. 93% of patients (14 of 15) with PR, CR or surgical CR remain alive. Ten additional patients had SD for >3 months. Kaplan Meier one year survival is 61% overall, 58% stage IV only, 48% for Stage IV M1c. The median OS is 16+ months. Conclusions: The 1-year survival and durable objective response rate are encouraging. Responses of distant and visceral disease provide further compelling evidence of systemic effectiveness. This, combined with a limited toxicity profile, suggests OncoVEXGM-CSF is a promising treatment for metastatic melanoma. A phase III clinical trial is planned.

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Proof concept for clinical justification of network mapping for personalized cancer therapeutics

To identify signature targets associated with patient-specific cancer lesions based on tumor versus normal tissue differential protein and mRNA coexpression patterns for the purpose of synthesizing cancer-specific customized RNA interference knockdown therapeutics. Analysis of biopsied tissue involved two-dimensional difference in-gel electrophoresis (2D-DIGE) analysis coupled with MALDI-TOF/TOF mass spectrometry for proteomic assessment. Standard microarray techniques were utilized for mRNA analysis. Priority was assigned to overexpressed protein targets with co-overexpressed genes with a high likelihood of functional nodal centrality in the cancer network as defined by the interactive databases BIND, HPRD and ResNet. HPLC-grade small interfering RNA (siRNA) duplexes were utilized to assess knockdown of target proteins in expressive cell lines as measured by western blot. Seven patients with metastatic cancer underwent biopsy. One patient (RW001) had biopsies from two disease sites 10 months apart. Seven priority proteins were identified, one for each patient (RACK 1, Ras related nuclear protein, heat-shock 27 kDa protein 1, superoxide dismutase, enolase1, stathmin1 and cofilin1). Prioritized proteins in RW001 from the two disease sites over time were the same. We demonstrated >80% siRNA inhibition of RACK 1 and stathmin1 of inexpressive malignant cell lines with correlated cell kill. Identification of functionally relevant target gene fingerprints, unique to an individual's cancer, is feasible 'at the bedside' and can be utilized to synthesize siRNA knockdown therapeutics. Further animal safety testing followed by clinical study is recommended.