Durham, Nicholas M.

Background MEDI5395 is a recombinant attenuated Newcastle disease virus engineered to express a human granulocyte-macrophage colony-stimulating factor transgene. Preclinically, MEDI5395 demonstrated broad oncolytic activity, augmented by concomitant programmed cell death-1/programmed cell death ligand-1 (PD-L1) axis blockade. Durvalumab is an anti-PD-L1 immune checkpoint inhibitor approved for the treatment of various solid tumors. We describe the results of the first-in-human study combining intravenous MEDI5395 with durvalumab in patients with advanced solid tumors. Methods This phase I, open-label, multicenter, dose-escalation, dose-expansion study recruited adult patients with advanced solid tumors, who had relapsed or were refractory or intolerant to ≥1 prior line of standard treatment. MEDI5395 was administered intravenously as six doses over 15–18 days. The dose-escalation phase assessed four-dose levels (108, 109, 1010, 1011 focus forming units (FFU)) of MEDI5395, with sequential or delayed durvalumab. Durvalumab 1500 mg was administered intravenously every 4 weeks up to 2 years. The dose-expansion phase was not initiated. The primary objectives were to evaluate safety and tolerability, dose-limiting toxicities (DLTs) and the dose and schedule of MEDI5395 plus durvalumab administration. Secondary objectives included the assessment of the efficacy, pharmacokinetics, pharmacodynamics, and immunogenicity of MEDI5395. Results 39 patients were treated with MEDI5395; 36 patients also received durvalumab. All 39 patients experienced ≥1 treatment-emergent adverse event (TEAE), most commonly fatigue (61.5%), nausea (53.8%) and chills (51.3%). Grade 3–4 TEAEs occurred in 27 (69.2%) patients; these were deemed MEDI5395-related in 12 (30.8%) patients. Two patients experienced a DLT, and the maximum tolerated dose of MEDI5395 with sequential and delayed durvalumab at study termination was 1011 and 1010 FFU, respectively. Four patients (10.3%) achieved a partial response (PR). Patients with PR or stable disease tended to have higher baseline PD-L1 and CD8+ levels in their tumor tissue. A tendency to dose-dependent pharmacokinetics of the viral genome was observed in whole blood and a tendency to dose-dependent viral shedding was observed in saliva and urine. Neutralizing antibodies were observed in all patients but did not appear to impact efficacy negatively. Conclusion This study demonstrates the feasibility, safety and preliminary efficacy of MEDI5395 with durvalumab in patients with advanced solid tumors. Trial registration number NCT03889275

Abstract Purpose: The safety and preliminary efficacy of MEDI1873, an agonistic IgG1 fusion protein targeting glucocorticoid-induced TNF receptor–related protein (GITR), were evaluated in an open-label, first-in-human, phase I, dose escalation study in previously treated patients with advanced solid tumors. Patients and Methods: Two single-patient cohorts at 1.5 and 3 mg i.v. were followed by 3+3 dose escalation in six cohorts at 7.5, 25, 75, 250, 500, and 750 mg, all every 2 weeks, for up to 52 weeks. Primary endpoints were safety and tolerability, dose-limiting toxicities (DLT), and MTD. Secondary endpoints included antitumor activity, pharmacokinetics, immunogenicity, and pharmacodynamics. Results: Forty patients received MEDI1873. Three experienced DLTs: grade 3 worsening tumor pain (250 mg); grade 3 nausea, vomiting, and headache (500 mg); and grade 3 non-ST segment elevation myocardial infarction (750 mg). An MTD was not reached and treatment was well tolerated up to 500 mg. Most common treatment-related adverse events were headache (25%), infusion-related reaction (17.5%), and decreased appetite (17.5%). MEDI1873 exposure was dose proportional. Antidrug–antibody incidence was low. MEDI1873 increased peripheral CD4+ effector memory T-cell proliferation as well as cytokines associated with effector T-cell activation at dose levels ≥75 mg. The best response was stable disease (SD) in 17 patients (42.5%), including 1 unconfirmed partial response. Eight patients (20.0%) had SD ≥24 weeks. Conclusions: MEDI1873 showed acceptable safety up to 500 mg i.v. every 2 weeks with pharmacodynamics activity, and prolonged SD in some patients. However, further development is not planned because of lack of demonstrated tumor response.