RevImmune, Inc.

Patients with protracted sepsis develop impaired immunity, which predisposes them to acquiring secondary infections. One of the most common and lethal secondary infections is Pseudomonas aeruginosa pneumonia. Immunoadjuvant therapy is a promising approach to reverse sepsis-induced immunosuppression and improve morbidity and mortality from secondary infections. Interleukin-7 is an immunoadjuvant that improves survival in clinically relevant animal models of polymicrobial peritonitis and in fungal sepsis. This study investigated the effect of recombinant human interleukin-7 (rhIL-7) on survival in a 2-hit model of sublethal cecal ligation and puncture followed by P. aeruginosa pneumonia. Potential immunologic mechanisms responsible for the rhIL-7 putative beneficial effect were also examined, focusing on IL-17, IL-22, IFN-γ, and TNF-α, cytokines that are critical in the control of sepsis and pulmonary Pseudomonas infections. Results showed that rhIL-7 was highly effective in preventing P. aeruginosa–induced death, i.e., 92% survival in rhIL-7–treated mice versus 56% survival in control mice. rhIL-7 increased absolute numbers of immune effector cells in lung and spleen and ameliorated the sepsis-induced loss of lung innate lymphoid cells (ILCs). rhIL-7 also significantly increased IL-17–, IFN-γ–, and TNF-α–producing lung ILCs and CD8 T cells as well as IFN-γ– and TNF-α–producing splenic T cell subsets and ILCs. Furthermore, rhIL-7 enhanced NF-κB and STAT3 signaling in lungs during sepsis and pneumonia. Given the high mortality associated with secondary P. aeruginosa pneumonia, the ability of rhIL-7 to improve immunity and increase survival in multiple animal models of sepsis, and the remarkable safety profile of rhIL-7, clinical trials with rhIL-7 should be considered.

Purpose: Patients with metastatic or relapsed pediatric sarcomas receive cytotoxic regimens that induce high remission rates associated with profound lymphocyte depletion, but ultimately few survive long term. We administered adjuvant immunotherapy to patients with metastatic and recurrent pediatric sarcomas in an effort to improve outcomes.Experimental Design: Mononuclear cells were collected via apheresis, and tumor lysate was acquired via percutaneous biopsy at enrollment. Participants received standard antineoplastic therapy, followed by autologous lymphocytes, tumor lysate/keyhole limpet hemocyanin–pulsed dendritic cell vaccinations ± recombinant human IL7. Primary outcomes were toxicity and vaccine responses. Secondary outcomes were immune reconstitution, event-free survival, and overall survival (OS).Results: Forty-three patients enrolled and 29 received immunotherapy. The regimen was well tolerated. Intent-to-treat analysis demonstrated 5-year OS of 51% with significant differences based upon histologic group (63% vs. 0% for Ewing/rhabdomyosarcoma vs. other sarcomas) and response to standard therapy (74% no residual disease vs. 0% residual disease). Five-year intent-to-treat OS of patients with newly diagnosed metastatic Ewing/rhabdomyosarcoma was 77%, higher than previously reported in this population and higher than observed in a similar group treated with an earlier adjuvant immunotherapy regimen (25% 5-year OS). T-cell responses to autologous tumor lysate were identified in 62% of immunotherapy recipients, and survival was higher in those patients (73% 5-year OS with vs. 37% without immune response, P = 0.017). Immune reconstitution, measured by CD4 count recovery, was significantly enhanced in subjects treated with recombinant human IL7.Conclusions: Adjuvant immunotherapy may improve survival in patients with metastatic pediatric sarcoma. Clin Cancer Res; 22(13); 3182–91. ©2016 AACR.