Alexander M. Lesokhin

Nivolumab plus Ipilimumab in Advanced Melanoma

BACKGROUND In patients with melanoma, ipilimumab (an antibody against cytotoxic T-lymphocyte-associated antigen 4 [CTLA-4]) prolongs overall survival, and nivolumab (an antibody against the programmed death 1 [PD-1] receptor) produced durable tumor regression in a phase 1 trial. On the basis of their distinct immunologic mechanisms of action and supportive preclinical data, we conducted a phase 1 trial of nivolumab combined with ipilimumab in patients with advanced melanoma. METHODS We administered intravenous doses of nivolumab and ipilimumab in patients every 3 weeks for 4 doses, followed by nivolumab alone every 3 weeks for 4 doses (concurrent regimen). The combined treatment was subsequently administered every 12 weeks for up to 8 doses. In a sequenced regimen, patients previously treated with ipilimumab received nivolumab every 2 weeks for up to 48 doses. RESULTS A total of 53 patients received concurrent therapy with nivolumab and ipilimumab, and 33 received sequenced treatment. The objective-response rate (according to modified World Health Organization criteria) for all patients in the concurrent-regimen group was 40%. Evidence of clinical activity (conventional, unconfirmed, or immune-related response or stable disease for ≥24 weeks) was observed in 65% of patients. At the maximum doses that were associated with an acceptable level of adverse events (nivolumab at a dose of 1 mg per kilogram of body weight and ipilimumab at a dose of 3 mg per kilogram), 53% of patients had an objective response, all with tumor reduction of 80% or more. Grade 3 or 4 adverse events related to therapy occurred in 53% of patients in the concurrent-regimen group but were qualitatively similar to previous experience with monotherapy and were generally reversible. Among patients in the sequenced-regimen group, 18% had grade 3 or 4 adverse events related to therapy and the objective-response rate was 20%. CONCLUSIONS Concurrent therapy with nivolumab and ipilimumab had a manageable safety profile and provided clinical activity that appears to be distinct from that in published data on monotherapy, with rapid and deep tumor regression in a substantial proportion of patients. (Funded by Bristol-Myers Squibb and Ono Pharmaceutical; ClinicalTrials.gov number, NCT01024231.).

PD-1 Blockade with Nivolumab in Relapsed or Refractory Hodgkin's Lymphoma

BACKGROUND Preclinical studies suggest that Reed-Sternberg cells exploit the programmed death 1 (PD-1) pathway to evade immune detection. In classic Hodgkins lymphoma, alterations in chromosome 9p24.1 increase the abundance of the PD-1 ligands, PD-L1 and PD-L2, and promote their induction through Janus kinase (JAK)-signal transducer and activator of transcription (STAT) signaling. We hypothesized that nivolumab, a PD-1-blocking antibody, could inhibit tumor immune evasion in patients with relapsed or refractory Hodgkins lymphoma. METHODS In this ongoing study, 23 patients with relapsed or refractory Hodgkins lymphoma that had already been heavily treated received nivolumab (at a dose of 3 mg per kilogram of body weight) every 2 weeks until they had a complete response, tumor progression, or excessive toxic effects. Study objectives were measurement of safety and efficacy and assessment of the PDL1 and PDL2 (also called CD274 and PDCD1LG2, respectively) loci and PD-L1 and PD-L2 protein expression. RESULTS Of the 23 study patients, 78% were enrolled in the study after a relapse following autologous stem-cell transplantation and 78% after a relapse following the receipt of brentuximab vedotin. Drug-related adverse events of any grade and of grade 3 occurred in 78% and 22% of patients, respectively. An objective response was reported in 20 patients (87%), including 17% with a complete response and 70% with a partial response; the remaining 3 patients (13%) had stable disease. The rate of progression-free survival at 24 weeks was 86%; 11 patients were continuing to participate in the study. Reasons for discontinuation included stem-cell transplantation (in 6 patients), disease progression (in 4 patients), and drug toxicity (in 2 patients). Analyses of pretreatment tumor specimens from 10 patients revealed copy-number gains in PDL1 and PDL2 and increased expression of these ligands. Reed-Sternberg cells showed nuclear positivity of phosphorylated STAT3, indicative of active JAK-STAT signaling. CONCLUSIONS Nivolumab had substantial therapeutic activity and an acceptable safety profile in patients with previously heavily treated relapsed or refractory Hodgkins lymphoma. (Funded by Bristol-Myers Squibb and others; ClinicalTrials.gov number, NCT01592370.).

Immunologic Correlates of the Abscopal Effect in a Patient with Melanoma

The abscopal effect is a phenomenon in which local radiotherapy is associated with the regression of metastatic cancer at a distance from the irradiated site. The abscopal effect may be mediated by activation of the immune system. Ipilimumab is a monoclonal antibody that inhibits an immunologic checkpoint on T cells, cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4). We report a case of the abscopal effect in a patient with melanoma treated with ipilimumab and radiotherapy. Temporal associations were noted: tumor shrinkage with antibody responses to the cancer-testis antigen NY-ESO-1, changes in peripheral-blood immune cells, and increases in antibody responses to other antigens after radiotherapy. (Funded by the National Institutes of Health and others.).

Nivolumab in Patients With Relapsed or Refractory Hematologic Malignancy: Preliminary Results of a Phase Ib Study

PURPOSE Cancer cells can exploit the programmed death-1 (PD-1) immune checkpoint pathway to avoid immune surveillance by modulating T-lymphocyte activity. In part, this may occur through overexpression of PD-1 and PD-1 pathway ligands (PD-L1 and PD-L2) in the tumor microenvironment. PD-1 blockade has produced significant antitumor activity in solid tumors, and similar evidence has emerged in hematologic malignancies. METHODS In this phase I, open-label, dose-escalation, cohort-expansion study, patients with relapsed or refractory B-cell lymphoma, T-cell lymphoma, and multiple myeloma received the anti-PD-1 monoclonal antibody nivolumab at doses of 1 or 3 mg/kg every 2 weeks. This study aimed to evaluate the safety and efficacy of nivolumab and to assess PD-L1/PD-L2 locus integrity and protein expression. RESULTS Eighty-one patients were treated (follicular lymphoma, n = 10; diffuse large B-cell lymphoma, n = 11; other B-cell lymphomas, n = 10; mycosis fungoides, n = 13; peripheral T-cell lymphoma, n = 5; other T-cell lymphomas, n = 5; multiple myeloma, n = 27). Patients had received a median of three (range, one to 12) prior systemic treatments. Drug-related adverse events occurred in 51 (63%) patients, and most were grade 1 or 2. Objective response rates were 40%, 36%, 15%, and 40% among patients with follicular lymphoma, diffuse large B-cell lymphoma, mycosis fungoides, and peripheral T-cell lymphoma, respectively. Median time of follow-up observation was 66.6 weeks (range, 1.6 to 132.0+ weeks). Durations of response in individual patients ranged from 6.0 to 81.6+ weeks. CONCLUSION Nivolumab was well tolerated and exhibited antitumor activity in extensively pretreated patients with relapsed or refractory B- and T-cell lymphomas. Additional studies of nivolumab in these diseases are ongoing.

OX40 engagement and chemotherapy combination provides potent antitumor immunity with concomitant regulatory T cell apoptosis

Expansion and recruitment of CD4+ Foxp3+ regulatory T (T reg) cells are mechanisms used by growing tumors to evade immune elimination. In addition to expansion of effector T cells, successful therapeutic interventions may require reduction of T reg cells within the tumor microenvironment. We report that the combined use of the alkylating agent cyclophosphamide (CTX) and an agonist antibody targeting the co-stimulatory receptor OX40 (OX86) provides potent antitumor immunity capable of regressing established, poorly immunogenic B16 melanoma tumors. CTX administration resulted in tumor antigen release, which after OX86 treatment significantly enhanced the antitumor T cell response. We demonstrated that T reg cells are an important cellular target of the combination therapy. Paradoxically, the combination therapy led to an expansion of T reg cells in the periphery. In the tumor, however, the combination therapy induced a profound T reg cell depletion that was accompanied by an influx of effector CD8+ T cells leading to a favorable T effector/T reg cell ratio. Closer examination revealed that diminished intratumoral T reg cell levels resulted from hyperactivation and T reg cell–specific apoptosis. Thus, we propose that CTX and OX40 engagement represents a novel and rational chemoimmunotherapy.

Monocytic CCR2(+) myeloid-derived suppressor cells promote immune escape by limiting activated CD8 T-cell infiltration into the tumor microenvironment.

Myeloid-derived suppressor cells (MDSC) are a heterogeneous population of cells that accumulate during tumor formation, facilitate immune escape, and enable tumor progression. MDSCs are important contributors to the development of an immunosuppressive tumor microenvironment that blocks the action of cytotoxic antitumor T effector cells. Heterogeneity in these cells poses a significant barrier to studying the in vivo contributions of individual MDSC subtypes. Herein, we show that granulocyte-macrophage colony stimulating factor, a cytokine critical for the numeric and functional development of MDSC populations, promotes expansion of a monocyte-derived MDSC population characterized by expression of CD11b and the chemokine receptor CCR2. Using a toxin-mediated ablation strategy to target CCR2-expressing cells, we show that these monocytic MDSCs regulate entry of activated CD8 T cells into the tumor site, thereby limiting the efficacy of immunotherapy. Our results argue that therapeutic targeting of monocytic MDSCs would enhance outcomes in immunotherapy.

Survival, response duration, and activity by BRAF mutation (MT) status of nivolumab (NIVO, anti-PD-1, BMS-936558, ONO-4538) and ipilimumab (IPI) concurrent therapy in advanced melanoma (MEL).

LBA9003^ Background: We report updated survival and clinical activity in initially enrolled cohorts and activity by BRAF MT status in a phase I trial of concurrent and sequenced NIVO + IPI. METHODS MEL pts (n=53, enrolled 2009-2012, data analysis Dec 2013) with ≤3 prior therapies received IV concurrent NIVO + IPI, Q3Wk × 4 doses, followed by NIVO Q3Wk × 4. At wk 24, NIVO + IPI continued Q12Wk × 8 in pts with disease control and no DLT. Tumor responses were evaluated by WHO and immune-related criteria. RESULTS Pt characteristics included stage M1c: 55% and prior systemic therapy: 40%. Across doses, 1- and 2-y OS rates were 82% and 75%. Clinical activity was similar to previous reports except CRs rose to 9/53 (17%). Pts with/without tumor BRAF MT (n=36) had similar activity (Table). By wk 36, 42% demonstrated ≥80% tumor reduction. Median duration of response (DOR) was not reached (NR). Of 22 pts with objective response, 14 (64%) had DOR ≥24 wk (range: 25+, 106+). Treatment-related adverse events were as reported previously: grade 3-4, 53% of pts; most common: ↑ lipase and AST (13% ea). Data for sequenced cohorts are shown (Table). CONCLUSIONS Concurrent NIVO + IPI therapy showed encouraging survival and a manageable safety profile in advanced MEL pts. Responses were observed regardless of BRAF MT status and were durable in the majority of pts. Forty additional pts were enrolled (last pt: Nov 2013) on a cohort of NIVO 1 mg/kg + IPI 3 mg/kg Q3Wk × 4 doses, followed by NIVO 3mg/kg Q2Wk (the selected regimen for phase II/III trials). CLINICAL TRIAL INFORMATION NCT01024231. [Table: see text].

Pneumonitis in Patients Treated With Anti-Programmed Death-1/Programmed Death Ligand 1 Therapy.

Purpose Pneumonitis is an uncommon but potentially fatal toxicity of anti-programmed death-1 (PD-1)/programmed death ligand 1 (PD-L1) monoclonal antibodies (mAbs). Clinical, radiologic, and pathologic features are poorly described. Methods Patients who received anti-PD-1/PD-L1 monotherapy or in combination with anti-cytotoxic T-cell lymphocyte-4 mAb were identified at two institutions (Memorial Sloan Kettering Cancer Center: advanced solid cancers, 2009 to 2014, and Melanoma Institute of Australia: melanomas only, 2013 to 2015). Pneumonitis was diagnosed by the treating investigator; cases with confirmed malignant lung infiltration or infection were excluded. Clinical, radiologic, and pathologic features of pneumonitis were collected. Associations among pneumonitis incidence, therapy received, and underlying malignancy were examined with Fishers exact test as were associations between pneumonitis features and outcomes. Results Of 915 patients who received anti-PD-1/PD-L1 mAbs, pneumonitis developed in 43 (5%; 95% CI, 3% to 6%; Memorial Sloan Kettering Cancer Center, 27 of 578 [5%]; Melanoma Institute of Australia, 16 of 337 [5%]). Time to onset of pneumonitis ranged from 9 days to 19.2 months. The incidence of pneumonitis was higher with combination immunotherapy versus monotherapy (19 of 199 [10%] v 24 of 716 [3%]; P < .01). Incidence was similar in patients with melanoma and non-small-cell lung cancer (overall, 26 of 532 [5%] v nine of 209 [4%]; monotherapy, 15 of 417 v five of 152 [ P = 1.0]; combination, 11 of 115 v four of 57 [ P = .78]). Seventy-two percent (31 of 43) of cases were grade 1 to 2, and 86% (37 of 43) improved/resolved with drug holding/immunosuppression. Five patients worsened clinically and died during the course of pneumonitis treatment; proximal cause of death was pneumonitis (n = 1), infection related to immunosuppression (n = 3), or progressive cancer (n = 1). Radiologic and pathologic features of pneumonitis were diverse. Conclusion Pneumonitis associated with anti-PD-1/PD-L1 mAbs is a toxicity of variable onset and clinical, radiologic, and pathologic appearances. It is more common when anti-PD-1/PD-L1 mAbs are combined with anti-cytotoxic T-cell lymphocyte-4 mAb. Most events are low grade and improve/resolve with drug holding/immunosuppression. Rarely, pneumonitis worsens despite immunosuppression, and may result in infection and/or death.

On being less tolerant: Enhanced cancer immunosurveillance enabled by targeting checkpoints and agonists of T cell activation

This Review presents the state of research and future outlook on cancer immunotherapy approaches such as immune checkpoint inhibitors. The recent approvals of two drugs that block the function of the immune checkpoint programmed cell death 1 (PD-1) have firmly planted tumor immunotherapy in the mainstream of clinical oncology. We provide a historical and immunologic context for these recent advances and discuss translational studies that provide insight into the efficacy of cancer immunotherapy at the individual patient level.

Induction of tumoricidal function in CD4+ T cells is associated with concomitant memory and terminally differentiated phenotype

OX40 engagement induces a cytotoxic CD4+ T cell subpopulation to eradicate advance melanomas