Systematic review and meta-analysis evaluating the impact of antibiotic use on the clinical outcomes of patients with cancer treated with immune checkpoint inhibitors

2585

Background: In recent years, the gut microbiome has increasingly emerged as influencing the response to immune checkpoint inhibitors (ICIs) and antibiotic (ABX) exposure has repeatedly been shown to impair clinical outcomes of patients suffering from different cancer types and treated with ICIs. We published in 2020 a meta-analysis confirming that ABX use hampered survival of non-small cell lung cancer (NSCLC) patients treated with ICIs. The present study aims to determine whether ABX use also reduces survival of patients receiving ICIs for other cancers. Methods: PubMed and major oncology conferences’ proceedings were systematically searched to identify studies assessing the impact of ABX on the clinical outcomes of cancer patients treated with ICIs. Studies were included when reporting data on Overall Survival (OS), Progression-Free Survival (PFS), Overall Response Rate (ORR) and Progressive Disease Rate (PD), according to ABX exposure. Pooled Hazard Ratios (HRs) for OS and PFS and Odds Ratios (ORs) for ORR and PD were calculated, as well as HRs for OS and PFS according to different cancer types and different ABX exposure time windows (TWs). Results: Overall, 94 independent cohorts were included, representing 26,174 patients suffering from various types of cancer. The pooled HRs for PFS (61 cohorts, 13,224 patients) and OS (88 cohorts, 25,480 patients) were 1.47 [95% Confidence Interval (CI) 1.31-1.66] and 1.66 [95% CI 1.50-1.83], respectively, confirming a significant harmful impact of ABX on patient’ survival, observed across all cancer types (Table). The analyses of OS and PFS based on ABX exposure TWs suggested a stronger deleterious effect of ABX when taken around ICI treatment initiation. The response to treatment among ABX users was also impaired: the pooled ORs for ORR (30 cohorts, 4,590 patients) and PD (33 cohorts, 4,972 patients) were 0.55 [95% CI 0.39-0.77] and 1.97 [95% CI 1.48-2.64], respectively. Conclusions: ABX were shown to impair the clinical outcomes of cancer patients treated with ICIs, regardless of cancer type. [Table: see text]

278 Systematic review and meta-analysis evaluating the impact of antibiotic use on clinical outcomes of non-small-cell lung cancer patients treated with immune checkpoint inhibitors

Background

In recent years, the gut microbiome has increasingly emerged as influencing the response to immune checkpoint inhibitors (ICIs).1–3 Antibiotic (ABX) exposure, that leads to microbiome dysbiosis, was further shown in numerous studies to adversely influence the clinical outcomes of cancer patients treated with ICIs, especially in non-small-cell lung cancer (NSCLC).4–6We published in 2020 a meta-analysis confirming that ABX use could hamper survival of NSCLC patients treated with ICIs.7 The present study aims at updating this prior work by incorporating studies published until July 2021 and by studying new clinical outcomes.

Methods

PubMed and major oncology conferences’ proceedings were systematically searched to identify studies assessing the impact of ABX on the clinical outcomes of NSCLC patients treated with ICIs. Studies were included when reporting a hazard ratio (HR) or Kaplan–Meier curves for Overall Survival (OS) or Progression-Free Survival (PFS) based on antibiotic exposure, and/or data on treatment response such as Overall Response Rate (ORR) and Progressive Disease Rate (PD) according to antibiotic exposure. Pooled HRs for OS and PFS and Odds Ratios (OR) for ORR and PD were calculated, as well as HRs for OS and PFS according to different time windows of ABX exposure.

Results

Overall, 35 independent cohorts were included for a total of 12,235 patients. The pooled HRs for OS (12,235 patients) and PFS (5,356 patients) were 1.63 [95% Confidence Interval (CI) 1.37–1.94] and 1.49 [95% CI 1.26–1.76], respectively, confirming a significantly reduced survival in patients exposed to ABX. The subgroup analyses of OS and PFS based on the time window of ABX exposure (figures 1 and 2) suggest a harmful effect of ABX when taken around ICI initiation. The pooled OR for ORR (1,992 patients) and PD (1,272 patients) were 0.66 [95% CI 0.44–0.99] and 1.98 [95% CI 1.39–2.8], respectively, reflecting both a decreased odd of treatment response and an almost two-fold increased odd of cancer progression among ABX users (figures 3 and 4). These findings confirm the previously reported deleterious effect of ABX on all clinical outcomes (table 1).

Abstract 278 Figure 1

Forest plot of hazard ratios for overall survival of patients diagnosed with NSCLC and exposed to antibiotics versus not exposed to antibiotics, according to the time window of antibiotic exposure

Abstract 278 Figure 2

Forest plot of hazard ratios for progression-free survival of patients diagnosed with NSCLC and exposed to antibiotics versus not exposed to antibiotics, according to the time window of antibiotic exposure

Abstract 278 Figure 3

Forest plot of odds ratios for overall response rate of patients diagnosed with NSCLC and exposed to antibiotics versus not exposed to antibiotics

Abstract 278 Figure 4

Forest plot of odds ratios for progressive disease rate of patients diagnosed with NSCLC and exposed to antibiotics versus not exposed to antibiotics

Abstract 278 Table 1

Summary of the impact of antibiotic use on all clinical outcomes

Conclusions

Antibiotics were shown to impair clinical outcomes of NSCLC patients treated with ICIs in this study. Two (non mutually exclusive) mechanisms are increasingly discussed in the literature to explain the role of microbiome on immunotherapy response: the immunomodulatory effects of bacterial molecules,8 and antigenic mimicry between commensal bacteria and tumor antigens cross reactive for the same antigen specific T cells.9 10

References

Gopalakrishnan V, Spencer CN, Nezi L, Reuben A, Andrews MC, Karpinets TV, et al. Gut microbiome modulates response to anti-PD-1 immunotherapy in melanoma patients. Science 5 January 2018;359(6371):97–103.

Routy B, Le Chatelier E, Derosa L, Duong CPM, Alou MT, Daillère R, et al. Gut microbiome influences efficacy of PD-1-based immunotherapy against epithelial tumors. Science 5 January 2018;359(6371):91–7.

Matson V, Fessler J, Bao R, Chongsuwat T, Zha Y, Alegre M-L, et al. The commensal microbiome is associated with anti-PD-1 efficacy in metastatic melanoma patients. Science 5 January 2018;359(6371):104–8.

Derosa L, Hellmann MD, Spaziano M, Halpenny D, Fidelle M, Rizvi H, et al. Negative association of antibiotics on clinical activity of immune checkpoint inhibitors in patients with advanced renal cell and non-small-cell lung cancer. Ann Oncol Off J Eur Soc Med Oncol 1 June 2018;29(6):1437–44.

Pinato DJ, Howlett S, Ottaviani D, Urus H, Patel A, Mineo T, et al. Association of prior antibiotic treatment with survival and response to immune checkpoint inhibitor therapy in patients with cancer. JAMA Oncol 1 Décember 2019;5(12):1774–8.

Rounis K, Makrakis D, Papadaki C, Monastirioti A, Vamvakas L, Kalbakis K, et al. Prediction of outcome in patients with non-small cell lung cancer treated with second line PD-1/PDL-1 inhibitors based on clinical parameters: results from a prospective, single institution study. PloS One 2021;16(6):e0252537.

Lurienne L, Cervesi J, Duhalde L, de Gunzburg J, Andremont A, Zalcman G, et al. NSCLC immunotherapy efficacy and antibiotic use: a systematic review and meta-analysis. J Thorac Oncol Off Publ Int Assoc Study Lung Cancer July 2020;15(7):1147–59.

Sepich-Poore GD, Zitvogel L, Straussman R, Hasty J, Wargo JA, Knight R. The microbiome and human cancer. Science 26 March 2021;371(6536):eabc4552.

Fluckiger A, Daillère R, Sassi M, Sixt BS, Liu P, Loos F, et al. Cross-reactivity between tumor MHC class I-restricted antigens and an enterococcal bacteriophage. Science 21 août 2020;369(6506):936–42.

Bessell CA, Isser A, Havel JJ, Lee S, Bell DR, Hickey JW, et al. Commensal bacteria stimulate antitumor responses via T cell cross-reactivity. JCI Insight 23 avr 2020;5(8):135597.

Intergroup ALFA/GOELAMS randomized phase II trial of lirilumab anti-KIR monoclonal antibody (IPH2102/BMS986015) as maintenance treatment in elderly patients with acute myeloid leukemia (EFFIKIR trial)

TPS3117^

Background: Inhibitory killer immunoglobulin-like receptors (KIR) negatively regulate natural killer (NK) cell–mediated killing of HLA class I–expressing tumors. Lack of KIR-HLA class I interactions has been associated with potent NK cell-mediated antitumor efficacy and increased survival in patients with acute myeloid leukemia (AML) upon haploidentical stem cell transplantation from KIR-mismatched donors(Ruggeri, Blood 2007). Anti-KIR antibody treatment resulted in long-term survival in SCID mice inoculated with lethal autologous AML cells (Romagne, Blood 2009). Lirilumab is a second generation fully human monoclonal antibody targeting the major inhibitory KIR on NK cells. The objectives of this study are to determine if maintenance therapy with lirilumab can improve leukemia-free survival (LFS) of elderly patients in first complete remission (CR1) of AML and to assess two dose schedules leading to either intermittent or continuous KIR occupancy. Methods: EFFIKIR is a randomized double-blind 3-arm placebo controlled trial of lirilumab in elderly patients in CR1 of AML. Patients aged 60 to 80 in CR1 of AML following standard induction and consolidation programs are randomly allocated to receive placebo or lirilumab given at either 0.1 mg/kg q 12 weeks or 1 mg/kg q 4 weeks according to a minimization algorithm adjusting for center, primary vs. secondary AML, no. of consolidation cycles (1 vs. 2) and cytogenetics (intermediate vs. high risk). Patients are to receive up to 2 yrs of therapy. ECOG performance status of 0-1, adequate hematologic, liver and renal function, and recovery from toxicities of prior chemotherapies are required. Patients are excluded if they are eligible for bone marrow transplantation and if the time interval since last consolidation exceeds 3 mos. The primary endpoint is LFS based on independent central review. The trial will accrue 50 patients in each arm and is powered (80%) to detect an improvement in LFS with a hazard ratio of 0.60 and a one-sided alpha of 0.05. Each dose schedule will be compared to placebo using a Hochberg procedure. The first patient was randomized on 12/11/2012. Clinical trial information: NCT01687387.

Phase I study of recombinant human interleukin-7 administration in subjects with refractory malignancy

PURPOSE

Interleukin-7 (IL-7) has critical and nonredundant roles in T-cell development, hematopoiesis, and postdevelopmental immune functions as a prototypic homeostatic cytokine. Based on a large body of preclinical evidence, it may have multiple therapeutic applications in immunodeficiency states, either physiologic (immunosenescence), pathologic (HIV), or iatrogenic (postchemotherapy and posthematopoietic stem cell transplant), and may have roles in immune reconstitution or enhancement of immunotherapy. We report here on the toxicity and biological activity of recombinant human IL-7 (rhIL-7) in humans.

DESIGN

Subjects with incurable malignancy received rhIL-7 subcutaneously every other day for 2 weeks in a phase I interpatient dose escalation study (3, 10, 30, and 60 microg/kg/dose). The objectives were safety and dose-limiting toxicity determination, identification of a range of biologically active doses, and characterization of biological and, possibly, antitumor effects.

RESULTS

Mild to moderate constitutional symptoms, reversible spleen and lymph node enlargement, and marked increase in peripheral CD3(+), CD4(+), and CD8(+) lymphocytes were seen in a dose-dependent and age-independent manner in all subjects receiving >or=10 microg/kg/dose, resulting in a rejuvenated circulating T-cell profile, resembling that seen earlier in life. In some subjects, rhIL-7 induced in the bone marrow a marked, transient polyclonal proliferation of pre-B cells showing a spectrum of maturation as well as an increase in circulating transitional B cells.

CONCLUSION

This study shows the potent biological activity of rhIL-7 in humans over a well-tolerated dose range and allows further exploration of its possible therapeutic applications.

IL-7 administration drives T cell-cycle entry and expansion in HIV-1 infection

Interleukin 7 (IL-7) is a common gamma chain receptor cytokine implicated in thymopoiesis and in peripheral expansion and survival of T lymphocytes. The safety and activity of recombinant human IL-7 (rhIL-7) administration were therefore examined in HIV-infected persons. In this prospective randomized placebo-controlled study, a single subcutaneous dose of rhIL-7 was well tolerated with biologic activity demonstrable at 3 microg/kg and a maximum tolerated dose of 30 microg/kg. Injection site reactions and transient elevations of liver function tests were the most notable side effects. Transient increases in plasma HIV-RNA levels were observed in 6 of 11 IL-7-treated patients. Recombinant hIL-7 induced CD4 and CD8 T cells to enter cell cycle; cell-cycle entry was also confirmed in antigen-specific CD8 T cells. Administration of rhIL-7 led to transient down-regulation of the IL-7 receptor alpha chain (CD127) in both CD4(+) and CD8(+) T cells. Single-dose rhIL-7 increased the numbers of circulating CD4(+) and CD8(+) T cells, predominantly of central memory phenotype. The frequency of CD4(+) T cells with a regulatory T-cell phenotype (CD25(high) CD127(low)) did not change after rhIL-7 administration. Thus, rhIL-7 has a biologic and toxicity profile suggesting a potential for therapeutic trials in HIV infection and other settings of lymphopenia. This clinical trial has been registered at http://www.clinicaltrials.gov under NCT0099671.

Administration of rhIL-7 in humans increases in vivo TCR repertoire diversity by preferential expansion of naive T cell subsets

Interleukin-7 (IL-7) is a homeostatic cytokine for resting T cells with increasing serum and tissue levels during T cell depletion. In preclinical studies, IL-7 therapy exerts marked stimulating effects on T cell immune reconstitution in mice and primates. First-in-human clinical studies of recombinant human IL-7 (rhIL-7) provided the opportunity to investigate the effects of IL-7 therapy on lymphocytes in vivo. rhIL-7 induced in vivo T cell cycling, bcl-2 up-regulation, and a sustained increase in peripheral blood CD4⁺ and CD8⁺ T cells. This T cell expansion caused a significant broadening of circulating T cell receptor (TCR) repertoire diversity independent of the subjects' age as naive T cells, including recent thymic emigrants (RTEs), expanded preferentially, whereas the proportions of regulatory T (T reg) cells and senescent CD8⁺ effectors diminished. The resulting composition of the circulating T cell pool more closely resembled that seen earlier in life. This profile, distinctive among cytokines under clinical development, suggests that rhIL-7 therapy could enhance and broaden immune responses, particularly in individuals with limited naive T cells and diminished TCR repertoire diversity, as occurs after physiological (age), pathological (human immunodeficiency virus), or iatrogenic (chemotherapy) lymphocyte depletion.

IL-7 administration to humans leads to expansion of CD8+ and CD4+ cells but a relative decrease of CD4+ T-regulatory cells

Lymphopenia is a serious consequence of HIV infection and the administration of cancer chemotherapeutic agents. Although growth factors can be administered to patients to increase circulating neutrophils, there is no effective method to stimulate CD8+ lymphocyte production in humans, in vivo. This report is the first to describe the administration of recombinant interleukin-7 to humans and demonstrates the ability of this cytokine to mediate selective increases in CD4+ and CD8+ lymphocytes along with a decrease in the percentage of CD4+ T-regulatory cells. These studies suggest an important role for interleukin-7 in the treatment of patients with lymphopenia.

Effects of rhIL-7 administration in humans on in vivo expansion of naïve, memory and effector subsets of CD4+ & CD8+ T-cells

2504

Background: IL-7 has a critical and non-redundant role in T-cell lymphopoiesis and peripheral T-cell homeostasis. IL-7 administration may prove clinically valuable in conditions of disease induced (HIV) or iatrogenic T-cell depletion and for modulation of vaccine immune responses. In the first phase I study in humans, recombinant human interleukin-7 (“CYT 99–007”, Cytheris Inc., Rockville, MD) was administered subcutaneously every other day for two weeks in adults with refractory malignancies at 3, 10, 30 and 60 μg/kg/dose. Biologic activity, defined as a 50% increase over baseline of peripheral blood CD3+ T-cells, was seen at and above the 10μg/kg/dose in all patients. The kinetics of proliferation and expansion of peripheral blood T-cell subsets were analyzed. Methods: Multicolor flow cytometry was performed at baseline, 1, 2 and 3 weeks. Among CD4+ cells, the most naïve were defined as CD45RA+ /CD31+. Among CD4+ & CD8+ cells, the main naïve, memory and effector populations were defined respectively as CD45RA+/CD27+, CD45RA-/CD27+ and CD45RA-/CD27-. Within each subset, the number of cells in cycle was defined by Ki67 staining. Results: Following IL-7 therapy, there was marked proliferation of all T-cells subsets, peaking at week 1, most striking for the naive subsets with 30–70% of circulating cells induced to cycle. Proliferation rates were halved by week 2 despite continuation of treatment, coincident with the observed down-regulation of the IL-7 receptor. Cycling returned to baseline by week 3. Significant proliferation was also induced in effector and memory CD4+ and CD8+ T-cells but to a lesser magnitude, resulting in a greater net expansion of the naïve subsets, still ongoing one week after the end of treatment. Conclusions: IL-7 administration induces marked expansion of naïve, memory and effector CD4+ & CD8+ T-cells in humans. Consistent with the known down-regulation of the IL-7 receptor upon IL-7 exposure, proliferation rates decrease during the second week of treatment. rhIL-7 induced T-cell expansion may prove clinically valuable in adoptive immunotherapy as an adjunct to tumor vaccination and / or immunorestorative agent.

[Table: see text]

[T-cell-depleted HLA non-identical bone marrow transplantation in the child: prevention of graft-versus-host reaction by administration of donor T lymphocytes alloreactive against the recipient]

The success of HSCT from HLA partially disparate donors depends on the development of new strategies able to efficiently prevent GVHD and to protect patients from infections and relapse. Using an immunotoxin (IT) directed against the alpha-chain (p55) of the human IL-2r (RFT5-SMPT-dgA), we have previously shown that it is possible to kill mature T cells activated towards a specific HLA complex by a one-way MLR. We designed a clinical trial assessing the effect of infusing increasing doses of T lymphocytes in the setting of children recipients of non HLA genetically identical HSCT. Thirteen patients have been enrolled from September 1998 to April 2000 and fourteen HSCT have been realized in 13 patients (pts). Donors were MUD in 3 cases and familial HLA partially disparate in the remaining cases. Allodepleted donor T cells were injected between day +14 and day +30 provided that ATG was undetectable in the serum and blood PMN counts was > 500/microliter. The mean age of these patients was 17 months (range 1 to 42). Diagnosis included immune deficient and malignant hemopathies. Three patients received 1 x 10(5) allodepleted T cell/kg, 7 patients received 4 x 10(5)/kg and 4 patients received 6 x 10(5)/kg allodepleted T cells. Full inhibition of MLR was achieved in 12 out of 14 cases. In two cases, a residual T cell reactivity to the recipient was observed (4 to 5%) and patients developed grade II aGVHD. aGVHD occurred in 4 out of 11 grafted patients (all grade II). No chronic GVHD has developed, so far. Three patients died from severe VOD or PHT at day +34, day 51 and day +166, while one infected patient by VZV, CMV and EBV before HSCT died 6 months after transplantation from meningoencephalitis and another patient died from relapse at day +291. The patient for which there was no engraftment died at day +48 from staphylococcus infection. Overall survival is 54%, with a median follow up of 8 months; the mean time to reach a blood lymphocyte count > 500 was 41 days, to reach a CD3 count > 300 microliters 63 days (20-111), CD4 > 200 microliters 97 days and positive mitogen-induced proliferation 90 days. In three patients, a tetanus-toxoid positive proliferation was detected before immunization. From this intermediate analysis, we conclude that 1) specific allodepletion is an effective approach to prevent aGVHD in a haploincompatible setting, 2) data on immunological reconstitution suggest that infused T cells do survive and expand. A higher number of patients must be enrolled to determine the optimal number of T cells to infuse.

A randomized multicenter trial comparing leukocyte function-associated antigen-1 monoclonal antibody with rabbit antithymocyte globulin as induction treatment in first kidney transplantations

Adhesion molecules are involved in several steps in the immune response: leukocyte adhesion to the endothelium, transendothelial migration, cooperation between immunocompetent cells, and cytotoxicity. Leukocyte function-associated antigen-1 plays a central role among adhesion molecules. In a multicenter randomized open trial, we compared a monoclonal antibody directed against the alpha chain of LFA-1 (Oduli-momab; IMTIX/Pasteur Mérieux Sérums et Vaccins) with rabbit antithymocyte globulin (rATG; IMTIX/Pasteur Mérieux Sérums et Vaccins), as part of a quadruple sequential protocol in 101 patients receiving a first kidney transplant. Clinical tolerance of anti-LFA-1 mAb was better than that of rATG. Short-term rejection rates (< 15 days) were not significantly different (15% and 16% for anti-LFA-1 mAb and rATG, respectively). However, 11% of the anti-LFA-1 mAb patients experienced rejection during the first 10 days of the treatment course compared with none of the patients treated with rATG. The incidence and severity of acute rejection in the first 3 months was not significantly different between groups. Of the LFA-1 and rATG patients, 96% and 92% of the grafts, respectively, were functioning at 12 months. The incidence and severity of infection, whatever the origin, were comparable in both groups. In addition, it was observed that fewer patients required posttransplantation dialysis in the anti-LFA-1 mAb group (19%, vs. 35% for rATG), although the difference was not statistically significant. Altogether, the beneficial action of this monoclonal antibody on short-term renal function recovery makes it a useful tool in the management of renal patients undergoing kidney transplantation.

Virological markers in the cerebrospinal fluid from HIV-1-infected individuals

We analysed 127 specimens of cerebrospinal fluid (CSF) from 118 HIV-1-infected individuals at different stages of infection. Intrathecal antibody synthesis was evident in 23 samples tested and was more frequently directed against HIV than against rubella virus, herpes simplex virus, varicella zoster virus or cytomegalovirus. HIV was isolated from only 14% of the 127 CSF specimens, but from 82% of CSF-paired blood samples. HIV antigen was detected in 12% of CSF specimens and 44% of paired plasma samples. Twenty specimens analysed using the polymerase chain reaction (PCR) detected proviral DNA in 75% of CSF specimens. The low rate of virus recovery from CSF was caused by neither the freezing of specimens prior to culture nor therapy. In contrast, virus isolation from CSF was significantly associated with CSF cell count. Virus isolation and antigen detection in CSF were not correlated with either the Centers for Disease Control disease stage or the peripheral CD4+ lymphocyte count, whereas viraemia was significantly associated with a low CD4+ lymphocyte count. Moreover, virus isolation and antigen detection in CSF were not associated with symptoms of subacute HIV encephalitis, suggesting that these markers are not of potential value in the diagnosis of HIV-specific neurologic complications. The value of PCR in this field merits further investigation.

[Study of human immunodeficiency virus in the cerebrospinal fluid. Value and limitations]

Several markers of HIV infection can be detected in the cerebrospinal fluid, including viruses that are replicable in cell cultures, viral antigens and, at an early stage, stigmas of immunization against the virus. Some studies make a distinction between HIV isolated in cerebrospinal fluid and in serum. Cerebrospinal HIV isolates differ from serum isolates in their macrophage tropism, their antigenicity and their low cytotoxicity, but there is little difference in their capacity for replication. Studies aimed at finding virological markers to diagnose HIV-induced neurological lesions have given discordant results. Longitudinal studies are necessary to determine prognostic markers. New techniques, such as amplification by polymerase chain reaction, will perhaps provide new data.