Explore the vast range of titles available.

Background. The immune deficiency of human immunodeficiency virus (HIV) infection is not fully corrected with ARV therapy. Interleukin-7 (IL-7) can boost CD4 T-cell counts, but optimal dosing and mechanisms of cellular increases need to be defined. Methods. We performed a randomized placebo-controlled dose escalation (10, 20 and 30 μg/kg) trial of 3 weekly doses of recombinant human IL-7 (rhIL-7) in ARV-treated HIV-infected persons with CD4 T-cell counts between 101 and 400 cells/μL and plasma HIV levels <50 copies/mL. Toxicity, activity and the impact of rhIL-7 on immune reconstitution were monitored. Results. Doses of rhIL-7 up to 20 μg/kg were well tolerated. CD4 increases of predominantly naive and central memory T cells were brisk (averaging 323 cells/μL at 12 weeks) and durable (up to 1 year). Increased cell cycling and transient increased bcl-2 expression were noted. Expanded cells did not have the characteristics of regulatory or activated T cells. Transient low-level HIV viremia was seen in 6 of 26 treated patients; modest increases in total levels of intracellular HIV DNA were proportional to CD4 T-cell expansions. IL-7 seemed to increase thymic output and tended to improve the T-cell receptor (TCR) repertoire in persons with low TCR diversity. Conclusions. Three weekly doses of rhIL-7 at 20 μg/kg are well tolerated and lead to a dose-dependent CD4 T-cell increase and the broadening of TCR diversity in some subjects. These data suggest that this rhIL-7 dose could be advanced in future rhIL-7 clinical studies. Clinical Trials Registration. NCT0047732.

Lymphopenia and failure of lymphocytes to mount an early IFN-γ response correlate with increased mortality in COVID-19. Given the essential role of CD4 helper and CD8 cytotoxic cells in eliminating viral pathogens, this profound loss in lymphocytes may impair patients' ability to eliminate the virus. IL-7 is a pleiotropic cytokine that is obligatory for lymphocyte survival and optimal function. We conducted a prospective, double-blind, randomized, placebo-controlled trial of CYT107, recombinant human IL-7, in 109 critically ill, patients with lymphopenia who have COVID-19. The primary endpoint was to assess CYT107's effect on lymphocyte recovery with secondary clinical endpoints including safety, ICU and hospital length-of-stay, incidence of secondary infections, and mortality. CYT107 was well tolerated without precipitating a cytokine storm or worsening pulmonary function. Absolute lymphocyte counts increased in both groups without a significant difference between CYT107 and placebo. Patients with COVID-19 receiving CYT107 but not concomitant antiviral medications, known inducers of lymphopenia, had a final lymphocyte count that was 43% greater than placebo (P = 0.067). There were significantly fewer treatment-emergent adverse events in CYT107 versus placebo-treated patients (P < 0.001), consistent with a beneficial drug effect. Importantly, CYT107-treated patients had 44% fewer hospital-acquired infections versus placebo-treated patients (P = 0.014). Given that hospital-acquired infections are responsible for a large percentage of COVID-19 deaths, this effect of CYT107 to decrease nosocomial infections could substantially reduce late morbidity and mortality in this highly lethal disease. The strong safety profile of CYT107 and its excellent tolerability provide support for trials of CYT107 in other potential pandemic respiratory viral infections. NCT04379076, NCT04426201, NCT04442178, NCT04407689, NCT04927169. Funding for the trial was provided by RevImmune and the Cancer Research Institute.

BackgroundSipuleucel-T (sip-T) is a Food and Drug Administration (FDA)-approved autologous cellular immunotherapy for metastatic castration-resistant prostate cancer (mCRPC). We hypothesized that combining sip-T with interleukin (IL)-7, a homeostatic cytokine that enhances both B and T cell development and proliferation, would augment and prolong antigen-specific immune responses against both PA2024 (the immunogen for sip-T) and prostatic acid phosphatase (PAP).MethodsFifty-four patients with mCRPC treated with sip-T were subsequently enrolled and randomized 1:1 into observation (n=26) or IL-7 (n=28) arms of a phase II clinical trial (NCT01881867). Recombinant human (rh) IL-7 (CYT107) was given weekly×4. Immune responses were evaluated using flow cytometry, mass cytometry (CyTOF), interferon (IFN)-γ ELISpot, 3H-thymidine incorporation, and ELISA.ResultsTreatment with rhIL-7 was well tolerated. For the rhIL-7-treated, but not observation group, statistically significant lymphocyte subset expansion was found, with 2.3–2.6-fold increases in CD4+T, CD8+T, and CD56bright NK cells at week 6 compared with baseline. No significant differences in PA2024 or PAP-specific T cell responses measured by IFN-γ ELISpot assay were found between rhIL-7 and observation groups. However, antigen-specific T cell proliferative responses and humoral IgG and IgG/IgM responses significantly increased over time in the rhIL-7-treated group only. CyTOF analyses revealed pleiotropic effects of rhIL-7 on lymphocyte subsets, including increases in CD137 and intracellular IL-2 and IFN-γ expression. While not powered to detect clinical outcomes, we found that 31% of patients in the rhIL-7 group had prostate specific antigen (PSA) doubling times of >6 months, compared with 14% in the observation group.ConclusionsTreatment with rhIL-7 led to a significant expansion of CD4+ and CD8+ T cells, and CD56bright natural killer (NK) cells compared with observation after treatment with sip-T. The rhIL-7 treatment also led to improved antigen-specific humoral and T cell proliferative responses over time as well as to increased expression of activation markers and beneficial cytokines. This is the first study to evaluate the use of rhIL-7 after sip-T in patients with mCRPC and demonstrates encouraging results for combination approaches to augment beneficial immune responses.

Recombinant human interleukin‐7 hybrid Fc (rhIL‐7‐hyFc) is a homodimer of rhIL‐7 fused to a hyFc. Exogenous IL‐7 promotes T cell proliferation and increases lymphocyte count, making it a potential treatment option for lymphopenia and cancer. To improve therapeutic efficacy, rhIL‐7‐hyFc was developed as a long‐acting IL‐7. This study aimed to create a pharmacokinetic model for rhIL‐7‐hyFc by incorporating neonatal Fc receptor (FcRn)‐mediated recycling and target‐mediated drug disposition (TMDD) of the IL‐7 receptor. Data were collected from a randomized, double‐blind, placebo‐controlled phase 1 trial involving 30 healthy volunteers who received single doses of rhIL‐7‐hyFc. Volunteers received 20 or 60 mg/kg subcutaneously, 60 mg/kg intramuscularly (IM), or a placebo. Clinical data were provided by Genexine Inc. (Seoul, Republic of Korea). A TMDD‐FcRn–mediated recycling pharmacokinetic model was developed using NONMEM 7.5 software, assisted by PsN 5.3.1 software. A quasi‐steady‐state approximation was used to describe drug‐receptor and drug‐FcRn interactions. The model evaluation included goodness of fit, visual predictive checks, and bootstrap analysis. Based on the pharmacokinetic parameters of the final model, a simulation was conducted to select the dosage regimen, ensuring a probability of at least 0.8 for meeting both safety and efficacy criteria. The model successfully described the pharmacokinetic profiles of 24 patients administered rhIL‐7‐hyFc. Based on the simulation results, 670–800 μg/kg every 3 weeks, 1010–1530 μg/kg every 6 weeks, and 1510–2190 μg/kg every 9 weeks IM were proposed. These results may help further understand rhIL‐7‐hyFc characteristics and, moreover, provide guidance for selecting the appropriate dosing regimen in future clinical trials.

Despite antiretroviral therapy (ART), some HIV-infected persons maintain lower than normal CD4(+) T-cell counts in peripheral blood and in the gut mucosa. This incomplete immune restoration is associated with higher levels of immune activation manifested by high systemic levels of biomarkers, including sCD14 and D-dimer, that are independent predictors of morbidity and mortality in HIV infection. In this 12-week, single-arm, open-label study, we tested the efficacy of IL-7 adjunctive therapy on T-cell reconstitution in peripheral blood and gut mucosa in 23 ART suppressed HIV-infected patients with incomplete CD4(+) T-cell recovery, using one cycle (consisting of three subcutaneous injections) of recombinant human IL-7 (r-hIL-7) at 20 µg/kg. IL-7 administration led to increases of both CD4(+) and CD8(+) T-cells in peripheral blood, and importantly an expansion of T-cells expressing the gut homing integrin α4β7. Participants who underwent rectosigmoid biopsies at study baseline and after treatment had T-cell increases in the gut mucosa measured by both flow cytometry and immunohistochemistry. IL-7 therapy also resulted in apparent improvement in gut barrier integrity as measured by decreased neutrophil infiltration in the rectosigmoid lamina propria 12 weeks after IL-7 administration. This was also accompanied by decreased TNF and increased FOXP3 expression in the lamina propria. Plasma levels of sCD14 and D-dimer, indicative of systemic inflammation, decreased after r-hIL-7. Increases of colonic mucosal T-cells correlated strongly with the decreased systemic levels of sCD14, the LPS coreceptor - a marker of monocyte activation. Furthermore, the proportion of inflammatory monocytes expressing CCR2 was decreased, as was the basal IL-1β production of peripheral blood monocytes. These data suggest that administration of r-hIL-7 improves the gut mucosal abnormalities of chronic HIV infection and attenuates the systemic inflammatory and coagulation abnormalities that have been linked to it.

Chimeric antigen receptor (CAR)-T cells expressing the cytokines IL-7 and CCL19 show improved clearance of established solid tumors in mice. Infiltration, accumulation, and survival of chimeric antigen receptor T (CAR-T) cells in solid tumors is crucial for tumor clearance. We engineered CAR-T cells to express interleukin (IL)-7 and CCL19 (7 × 19 CAR-T cells), as these factors are essential for the maintenance of T-cell zones in lymphoid organs. In mice, 7 × 19 CAR-T cells achieved complete regression of pre-established solid tumors and prolonged mouse survival, with superior anti-tumor activity compared to conventional CAR-T cells. Histopathological analyses showed increased infiltration of dendritic cells (DC) and T cells into tumor tissues following 7 × 19 CAR-T cell therapy. Depletion of recipient T cells before 7 × 19 CAR-T cell administration dampened the therapeutic effects of 7 × 19 CAR-T cell treatment, suggesting that CAR-T cells and recipient immune cells collaborated to exert anti-tumor activity. Following treatment of mice with 7 × 19 CAR-T cells, both recipient conventional T cells and administered CAR-T cells generated memory responses against tumors.

Interleukin-7 (IL-7) is produced by stromal cells, keratinocytes, and epithelial cells in host tissues or tumors and exerts a wide range of immune effects mediated by the IL-7 receptor (IL-7R). IL-7 is primarily involved in regulating the development of B cells, T cells, natural killer cells, and dendritic cells via the JAK-STAT, PI3K-Akt, and MAPK pathways. This cytokine participates in the early generation of lymphocyte subsets and maintain the survival of all lymphocyte subsets; in particular, IL-7 is essential for orchestrating the rearrangement of immunoglobulin genes and T-cell receptor genes in precursor B and T cells, respectively. In addition, IL-7 can aid the activation of immune cells in anti-virus and anti-tumor immunity and plays important roles in the restoration of immune function. These biological functions of IL-7 make it an important molecular adjuvant to improve vaccine efficacy as it can promote and extend systemic immune responses against pathogens by prolonging lymphocyte survival, enhancing effector cell activity, and increasing antigen-specific memory cell production. This review focuses on the biological function and mechanism of IL-7 and summarizes its contribution towards improved vaccine efficacy. We hope to provide a thorough overview of this cytokine and provide strategies for the development of the future vaccines.

Background. Phase I/II studies in human immunodeficiency virus (HIV)–infected patients receiving antiretroviral therapy have shown that a single cycle of 3 weekly subcutaneous (s/c) injections of recombinant human interleukin 7 (r-hIL-7) is safe and improves immune CD4 T-cell restoration. Herein, we report data from 2 phase II trials evaluating the effect of repeated cycles of r-hIL-7 (20 μg/kg) with the objective of restoring a sustained CD4 T-cell count >500 cells/μL. Methods. INSPIRE 2 was a single-arm trial conducted in the United States and Canada. INSPIRE 3 was a 2 arm trial with 3:1 randomization to r-hIL-7 versus control conducted in Europe and South Africa. Participants with plasma HIV RNA levels <50 copies/mL during antiretroviral therapy and with CD4 T-cell counts between 101 and 400 cells/μL were eligible. A repeat cycle was administered when CD4 T-cell counts fell to <550 cells/μL. Results. A total of 107 patients were treated and received 1 (n = 107), 2 (n = 74), 3 (n = 14), or 4 (n = 1) r-hIL-7 cycles during a median follow-up of 23 months. r-hIL-7 was well tolerated. Four grade 4 events were observed, including 1 case of asymptomatic alanine aminotransferase elevation. After the second cycle, anti-r-hIL-7 binding antibodies developed in 82% and 77% of patients in INSPIRE 2 and 3, respectively (neutralizing antibodies in 38% and 37%), without impact on the CD4 T-cell response. Half of the patients spent >63% of their follow-up time with a CD4 T-cell count >500 cells/μL. Conclusions. Repeated cycles of r-hIL-7 were well tolerated and achieved sustained CD4 T-cell restoration to >500 cells/μL in the majority of study participants. Clinical Trials Registration. INSPIRE II: clinicaltrials.gov (NCT01190111) and INSPIRE III: EudraCT (No. 2010-019773-15) and clinicaltrials.gov (NCT01241643).

A low lymphocyte count puts immune‐compromised patients at risk of mortality. hIL‐7‐hyFc is a homodimeric interleukin‐7 (IL‐7), a potent T‐cell amplifier, fused to the hybridizing IgD/IgG4 immunoglobulin domain. We performed a randomized, double‐blind, placebo‐controlled, dose‐escalation, phase I study to assess the pharmacokinetic, pharmacodynamic, safety, tolerability, and immunogenicity profiles of hIL‐7‐hyFc administered s.c. and i.m. to healthy volunteers. Thirty subjects randomly received hIL‐7‐hyFc or its matching placebo in an 8:2 ratio at 20, 60 μg/kg s.c., or 60 μg/kg i.m. The hIL‐7‐hyFc was slowly absorbed and its terminal half‐life was 63.26 hours after i.m. administration. The hIL‐7‐hyFc increased absolute lymphocyte count, mostly in T‐cells, which peaked 3 weeks after administration and then lasted for several additional weeks. The hIL‐7‐hyFc was well‐tolerated after a single s.c. and i.m. administration. Injection site reaction was the most common treatment‐emergent adverse event, which resolved spontaneously without treatment. The hIL‐7‐hyFc can be developed into a beneficial treatment option for patients with compromised T‐cell immunity. This trial was registered at www.clinicaltrials.gov as #NCT02860715.

BackgroundCD4+ T-cell lymphocytopenia and immune dysfunction are factors that drive the onset and persistence of Kaposi sarcoma (KS) in people with (PWH) and without HIV. Standard chemotherapy agents for KS can contribute to increasing CD4+ T cell lymphocytopenia. IL-7 is a cytokine that is essential in T-cell development, proliferation and homeostasis. In PWH, IL-7 administration leads to increased numbers of circulating central memory and naïve T-cell phenotypes.MethodsIn this multicenter phase I study with a 3+3 dose escalation design, participants with KS with or without HIV received up to four intramuscular injections of IL-7 (NT-I7) every 9 weeks. The primary endpoint of the study was to evaluate safety over three escalating dose levels (DL) of NT-I7 (DL1:480 µg/kg, DL2: 960 µg/kg and DL3: 1200 µg/kg) and identify a maximum tolerated dose. Secondary endpoints included evaluation of antitumor activity per the modified AIDS Clinical Trials Group Criteria and assessment of the effect of NT-I7 on the kinetics of CD4+ and CD8+ T-cells.ResultsEight cisgender male participants (five with HIV infection) were enrolled. Six participants were treated at DL1, and two were treated at DL2. The study was closed to accrual after enrolment of the second participant on DL2 due to termination of study funding. Four of the eight participants (three in DL1 and one in DL2) completed all four doses of the NT-I7. With regard to treatment-emergent adverse events (AEs), all participants had

Journal Article

Share this book

Add to My Shelf