A phase I oncolytic virus trial with vesicular stomatitis virus expressing human interferon beta and tyrosinase related protein 1 administered intratumorally and intravenously in uveal melanoma: safety, efficacy, and T cell responses

IntroductionMetastatic uveal melanoma (MUM) has a poor prognosis and treatment options are limited. These patients do not typically experience durable responses to immune checkpoint inhibitors (ICIs). Oncolytic viruses (OV) represent a novel approach to immunotherapy for patients with MUM.MethodsWe developed an OV with a Vesicular Stomatitis Virus (VSV) vector modified to express interferon-beta (IFN-β) and Tyrosinase Related Protein 1 (TYRP1) (VSV-IFNβ-TYRP1), and conducted a Phase 1 clinical trial with a 3 + 3 design in patients with MUM. VSV-IFNβ-TYRP1 was injected into a liver metastasis, then administered on the same day as a single intravenous (IV) infusion. The primary objective was safety. Efficacy was a secondary objective.Results12 patients with previously treated MUM were enrolled. Median follow up was 19.1 months. 4 dose levels (DLs) were evaluated. One patient at DL4 experienced dose limiting toxicities (DLTs), including decreased platelet count (grade 3), increased aspartate aminotransferase (AST), and cytokine release syndrome (CRS). 4 patients had stable disease (SD) and 8 patients had progressive disease (PD). Interferon gamma (IFNγ) ELIspot data showed that more patients developed a T cell response to virus encoded TYRP1 at higher DLs, and a subset of patients also had a response to other melanoma antigens, including gp100, suggesting epitope spreading. 3 of the patients who responded to additional melanoma antigens were next treated with ICIs, and 2 of these patients experienced durable responses.DiscussionOur study found that VSV-IFNβ -TYRP1 can be safely administered via intratumoral (IT) and IV routes in a previously treated population of patients with MUM. Although there were no clear objective radiographic responses to VSV-IFNβ-TYRP1, dose-dependent immunogenicity to TYRP1 and other melanoma antigens was seen

Distinct Signature of Oxylipid Mediators of Inflammation during Infection and Asymptomatic Colonization by E. coli in the Urinary Bladder

Urinary tract infection (UTI) is an extremely common infectious disease. Uropathogenic Escherichia coli (UPEC) is the predominant etiological agent of UTI. Asymptomatic bacteriuric E. coli (ABEC) strains successfully colonize the urinary tract resulting in asymptomatic bacteriuria (ABU) and do not induce symptoms associated with UTI. Oxylipids are key signaling molecules involved in inflammation. Based on the distinct clinical outcomes of E. coli colonization, we hypothesized that UPEC triggers the production of predominantly proinflammatory oxylipids and ABEC leads to production of primarily anti-inflammatory or proresolving oxylipids in the urinary tract. We performed quantitative detection of 39 oxylipid mediators with proinflammatory, anti-inflammatory, and proresolving properties, during UTI and ABU caused by genetically distinct E. coli strains in the murine urinary bladder. Our results reveal that infection with UPEC causes an increased accumulation of proinflammatory oxylipids as early as 6 h postinoculation, compared to controls. To the contrary, ABEC colonization leads to decreased accumulation of proinflammatory oxylipids at the early time point compared to UPEC infection but does not affect the level of proresolving oxylipids. This report represents the first comprehensive investigation on the oxylipidome during benign ABEC colonization observed in ABU and acute inflammation triggered by UPEC leading to UTI

Surface-modified measles vaccines encoding oligomeric, prefusion-stabilized SARS-CoV-2 spike glycoproteins boost neutralizing antibody responses to Omicron and historical variants, independent of measles seropositivity

ABSTRACTSerum titers of SARS-CoV-2-neutralizing antibodies (nAbs) correlate well with protection from symptomatic COVID-19 but decay rapidly in the months following vaccination or infection. In contrast, measles-protective nAb titers are lifelong after measles vaccination, possibly due to persistence of the live-attenuated virus in lymphoid tissues. We, therefore, sought to generate a live recombinant measles vaccine capable of driving high SARS-CoV-2 nAb responses. Since previous clinical testing of a live measles vaccine encoding a SARS-CoV-2 spike glycoprotein resulted in suboptimal anti-spike antibody titers, our new vectors were designed to encode prefusion-stabilized SARS-CoV-2 spike glycoproteins, trimerized via an inserted peptide domain, and displayed on a dodecahedral miniferritin scaffold. Additionally, to circumvent the blunting of vaccine efficacy by preformed anti-measles antibodies, we extensively modified the measles surface glycoproteins. Comprehensive in vivo mouse testing demonstrated the potent induction of high titer nAbs in measles-immune mice and confirmed the significant contributions to overall potency afforded by prefusion stabilization, trimerization, and miniferritin display of the SARS-CoV-2 spike glycoprotein. In animals primed and boosted with a measles virus (MeV) vaccine encoding the ancestral SARS-CoV-2 spike, high-titer nAb responses against ancestral virus strains were only weakly cross-reactive with the Omicron variant. However, in primed animals that were boosted with a MeV vaccine encoding the Omicron BA.1 spike, antibody titers to both ancestral and Omicron strains were robustly elevated, and the passive transfer of serum from these animals protected K18-ACE2 mice from infection and morbidity after exposure to BA.1 and WA1/2020 strains. Our results demonstrate that by engineering the antigen, we can develop potent measles-based vaccine candidates against SARS-CoV-2.IMPORTANCEAlthough the live-attenuated measles virus (MeV) is one of the safest and most efficacious human vaccines, a measles-vectored COVID-19 vaccine candidate expressing the SARS-CoV-2 spike failed to elicit neutralizing antibody (nAb) responses in a phase-1 clinical trial, especially in measles-immune individuals. Here, we constructed a comprehensive panel of MeV-based COVID-19 vaccine candidates using a MeV with extensive modifications on the envelope glycoproteins (MeV-MR). We show that artificial trimerization of the spike is critical for the induction of nAbs and that their magnitude can be significantly augmented when the spike protein is synchronously fused to a dodecahedral scaffold. Furthermore, preexisting measles immunity did not abolish heterologous immunity elicited by our vector. Our results highlight the importance of antigen optimization in the development of spike-based COVID-19 vaccines and therapies

Abstract CT090: Rational design of an oncolytic virus permits use of interferon beta as a pharmacodynamic marker for clinical application

Abstract Introduction. Voyager-V1 (VV1) is an oncolytic vesicular stomatitis virus engineered to express human interferon beta (IFNβ) to enhance cellular antitumor immune responses and tumor selectivity. VV1 also contains the human sodium iodide symporter (NIS) as an imaging gene. We report here the novel use of virus-encoded IFNβ as a PD marker using correlative data from three Phase I trials of VSV-IFNβ-NIS in patients with refractory cancers (n=46). Methods. 46 patients with solid tumors (n=34) and hematological malignancies (n=12) received 1 dose of VV1 either intratumorally (ITu) or intravenously (IV) at doses ranging from 3 x 106 to 5 x 1010 TCID50. Plasma IFNβ levels were collected pre-treatment, 4 hours post-infusion, Day 2 (24-hour), Day 3, 8, 15 and 29 (IT only). Samples were processed using a standard IFNβ specific ELISA kit. Results. ITu dose escalation is complete with 27 patients treated and no DLTs. IV escalation is ongoing at 5 x 1010 TCID50 with 19 patients treated to date. In the ITu study, plasma IFNβ levels at 24h were undetected at the lowest dose levels (up to 1 x 107 TCID50), and became detectable from 3 x 107 TCID50. In the IV patients, IFNβ was detectable at all dose levels (5 x 109 through 5 x 1010 TCID50) with the highest peak and longest duration in a patient with metastatic endometrial cancer coincident with shrinkage of multiple tumors. The IFNβ produced by virus-infected cells can be differentiated from the acute innate antiviral responses by magnitude of response and AUC as the majority of the inflammatory cytokines returned to baseline by 48h. Peak IFNβ levels were variable between patients, likely reflecting heterogeneity in tumor susceptibility to VV1, ranging from 1.4pg/mL to 656pg/mL across 6 patients (mean 153pg/ml) at the highest ITu dose. Plasma IFNβ 24 hours post-therapy of >20pg/mL appears to predict for RECIST 1.1-evaluated SD vs PD, p=0.048 in the ITu patients. Peak IFNβ ranged from 18 to 1700 pg/mL across 9 patients (mean=442pg/ml) at 1.7 x 1010 in the IV study. Peak IFNβ was highest in two cases of endometrial cancer (1500 and 1700 pg/ml). The patient with the highest IFNβ levels on the IV trial showed 16.7% tumor shrinkage at the first tumor evaluation. SPECT imaging, which shows location of viral replication, was positive in 50% of ITu injected tumors, also validating of VV1 infection of target cells. To date, SPECT images were negative in the IV trial despite IFNβ positivity, reflecting IFNβ as a more sensitive PD marker of viral infection. IHC staining of tumor biopsies collected pre-treatment and 1 month after VSV showed increased numbers of CD3, CD8, CD68, PDL1 or PD1 in some injected or noninjected tumors. Other immune markers and tumor gene signatures are also being evaluated. Conclusions. Plasma IFNβ has emerged as a simple and convenient biomarker of viral replication in tumors. IFNβ will be used in future studies as a PD marker to assess the impact of immune-modulating combination drugs with VV1. Citation Format: Timothy P. Cripe, Jamie Bakkum-Gamez, Jaime R. Merchan, Martha Q. Lacy, Manish R. Patel, Steven Powell, James Strauss, Lianwen Zhang, Toshie Sakuma, Memy Diaz, Nandakumar Packiriswamy, Deepak Upreti, Bethany Brunton, Dragan Jevremovic, Stephen J. Russell, Alice Bexon, Kah-Whye Peng. Rational design of an oncolytic virus permits use of interferon beta as a pharmacodynamic marker for clinical application [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr CT090