Michael Yellin

Improved Survival with Ipilimumab in Patients with Metastatic Melanoma

BACKGROUNDnAn improvement in overall survival among patients with metastatic melanoma has been an elusive goal. In this phase 3 study, ipilimumab--which blocks cytotoxic T-lymphocyte-associated antigen 4 to potentiate an antitumor T-cell response--administered with or without a glycoprotein 100 (gp100) peptide vaccine was compared with gp100 alone in patients with previously treated metastatic melanoma.nnnMETHODSnA total of 676 HLA-A*0201-positive patients with unresectable stage III or IV melanoma, whose disease had progressed while they were receiving therapy for metastatic disease, were randomly assigned, in a 3:1:1 ratio, to receive ipilimumab plus gp100 (403 patients), ipilimumab alone (137), or gp100 alone (136). Ipilimumab, at a dose of 3 mg per kilogram of body weight, was administered with or without gp100 every 3 weeks for up to four treatments (induction). Eligible patients could receive reinduction therapy. The primary end point was overall survival.nnnRESULTSnThe median overall survival was 10.0 months among patients receiving ipilimumab plus gp100, as compared with 6.4 months among patients receiving gp100 alone (hazard ratio for death, 0.68; P<0.001). The median overall survival with ipilimumab alone was 10.1 months (hazard ratio for death in the comparison with gp100 alone, 0.66; P=0.003). No difference in overall survival was detected between the ipilimumab groups (hazard ratio with ipilimumab plus gp100, 1.04; P=0.76). Grade 3 or 4 immune-related adverse events occurred in 10 to 15% of patients treated with ipilimumab and in 3% treated with gp100 alone. There were 14 deaths related to the study drugs (2.1%), and 7 were associated with immune-related adverse events.nnnCONCLUSIONSnIpilimumab, with or without a gp100 peptide vaccine, as compared with gp100 alone, improved overall survival in patients with previously treated metastatic melanoma. Adverse events can be severe, long-lasting, or both, but most are reversible with appropriate treatment. (Funded by Medarex and Bristol-Myers Squibb; ClinicalTrials.gov number, NCT00094653.)

Enterocolitis in Patients With Cancer After Antibody Blockade of Cytotoxic T-Lymphocyte–Associated Antigen 4

PURPOSEnCytotoxic T-lymphocyte-associated antigen 4 (CTLA4) is an inhibitory receptor on T cells. Knocking out CTLA4 in mice causes lethal lymphoproliferation, and polymorphisms in human CTLA4 are associated with autoimmune disease. Trials of the anti-CTLA4 antibody ipilimumab (MDX-010) have resulted in durable cancer regression and immune-mediated toxicities. A report on the diagnosis, pathology, treatment, clinical outcome, and significance of the immune-mediated enterocolitis seen with ipilimumab is presented.nnnPATIENTS AND METHODSnWe treated 198 patients with metastatic melanoma (MM) or renal cell carcinoma (RCC) with ipilimumab.nnnRESULTSnThe overall objective tumor response rate was 14%. We observed several immune mediated toxicities including dermatitis, enterocolitis, hypophysitis, uveitis, hepatitis, and nephritis. Enterocolitis, defined by grade 3/4 clinical presentation and/or biopsy documentation, was the most common major toxicity (21% of patients). It presented with diarrhea, and biopsies showed both neutrophilic and lymphocytic inflammation. Most patients who developed enterocolitis responded to high-dose systemic corticosteroids. There was no evidence that steroid administration affected tumor responses. Five patients developed perforation or required colectomy. Four other patients with steroid-refractory enterocolitis appeared to respond promptly to tumor necrosis factor alpha blockade with infliximab. Objective tumor response rates in patients with enterocolitis were 36% for MM and 35% for RCC, compared with 11% and 2% in patients without enterocolitis, respectively (P = .0065 for MM and P = .0016 for RCC).nnnCONCLUSIONnCTLA4 seems to be a significant component of tolerance to tumor and in protection against immune mediated enterocolitis and these phenomena are significantly associated in cancer patients.

Tumor Regression and Autoimmunity in Patients Treated With Cytotoxic T Lymphocyte–Associated Antigen 4 Blockade and Interleukin 2: A Phase I/II Study

BackgroundCytotoxic T lymphocyte–associated antigen (CTLA)-4 can inhibit T-cell responses and is involved in tolerance against self antigens. We previously reported autoimmune manifestations and objective cancer regressions in patients with metastatic melanoma treated with CTLA-4 blockade. The possibility of activating tumor-reactive T cells while removing inhibitory activity with CTLA-4 blockade has stimulated interest in using anti–CTLA-4 antibodies in combination with other cancer immunotherapies to improve clinical outcomes. In this study, we assessed the antitumor activity and autoimmune toxicity of CTLA-4 blockade in combination with an immune-activating stimulus, interleukin (IL)-2, in patients with metastatic melanoma.MethodsThirty-six patients received anti–CTLA-4 antibody every 3 weeks. Three patients per cohort received doses of .1, .3, 1.0, and 2.0 mg/kg. Twenty-four patients received 3.0 mg/kg. All patients received IL-2 therapy (720,000 IU/kg every 8 hours to a maximum of 15 doses).ResultsEight patients (22%) experienced objective tumor responses (three complete and five partial), including metastases in the lungs, lymph nodes, mediastinum, and subcutaneous tissues. Six of the eight patients have ongoing objective responses at 11 to 19 months. Five patients (14%) developed grade III/IV autoimmune toxicities secondary to anti–CTLA-4 administration, including four patients with enterocolitis and one with arthritis and uveitis.ConclusionsThere is not evidence to support a synergistic effect of CTLA-4 blockade plus IL-2 administration, because the 22% objective response rate is that expected from the sum of these two agents administered alone. Durable cancer regressions were seen in patients treated with this combination.

Prognostic factors related to clinical response in patients with metastatic melanoma treated by CTL-associated antigen-4 blockade.

Purpose: CTL-associated antigen 4 (CTLA-4) can inhibit T-cell activation and helps maintain peripheral self-tolerance. Previously, we showed immune-related adverse events (IRAE) and objective, durable clinical responses in patients with metastatic melanoma treated with CTLA-4 blockade. We have now treated 139 patients in two trials and have sufficient follow-up to examine factors associated with clinical response. Experimental Design: A total of 139 patients with metastatic melanoma were treated: 54 patients received ipilimumab in conjunction with peptide vaccinations and 85 patients were treated with intra-patient dose escalation of ipilimumab and randomized to receive peptides in accordance with HLA-A*0201 status. Results: Three patients achieved complete responses (CR; ongoing at 29+, 52+, and 53+ months); an additional 20 patients achieved partial responses (PR) for an overall objective response rate of 17%. The majority of patients (62%, 86 of 139) developed some form of IRAE, which was associated with a greater probability of objective antitumor response (P = 0.0004); all patients with CR had more severe IRAEs. Prior therapy with IFNα-2b was a negative prognostic factor, whereas prior high-dose interleukin-2 did not significantly affect the probability of response. There were no significant differences in the rate of clinical response or development of IRAEs between the two trials. The duration of tumor response was not affected by the use of high-dose steroids for abrogation of treatment-related toxicities (P = 0.23). There were no treatment-related deaths. Conclusion: In patients with metastatic melanoma, ipilimumab can induce durable objective clinical responses, which are related to the induction of IRAEs.

Phase I/II Study of Ipilimumab for Patients With Metastatic Melanoma

PURPOSEnThe primary objective of this phase I/II study was to determine the safety and pharmacokinetic profile of either transfectoma- or a hybridoma-derived ipilimumab. Secondary objectives included determination of a maximum-tolerated dose and assessment of clinical activity.nnnPATIENTS AND METHODSnEighty-eight patients with unresectable stage III or IV melanoma with at least one measurable lesion were treated. Mean age was 59 years, with 65% male and 35% female patients, and 79% of patients had received prior systemic therapy. Single doses of ipilimumab up to 20 mg/kg (group A, single dose), multiple doses up to 5 mg/kg (group A, multiple dose), and multiple doses up to 10 mg/kg (group B) were administered.nnnRESULTSnSingle dosing up to 20 mg/kg of transfectoma antibody was well tolerated, as were multiple doses up to 10 mg/kg without a maximum-tolerated dose. In group B, dose-limiting toxicity was seen in six of 23 melanoma patients. Grade 3 or 4 immune-related adverse events (irAEs) were observed in 14% of patients (12 of 88 patients), and grade 1 or 2 irAEs were seen in an additional 58%. The half-life of ipilimumab was 359 hours. In group B, there was one partial response (23+ months), one complete response (21+ months), and seven patients with stable disease (SD), for a disease control rate of 39%. Two patients in group B with SD had slow, steady decline in tumor burden that was ongoing at 1 year of observation.nnnCONCLUSIONnIpilimumab has activity in patients with metastatic melanoma. Late responses were observed in patients with prolonged SD.

Intrapatient dose escalation of anti-CTLA-4 antibody in patients with metastatic melanoma

We previously reported our experience in treating 56 patients with metastatic melanoma using a human anti-cytotoxic T-lymphocyte antigen 4 (CTLA-4) antibody. Durable tumor regressions were seen that correlated with the induction of autoimmune toxicities. In this study, we treated 46 additional patients using an intrapatient dose escalation schema to test whether higher doses of anti–CTLA-4 antibody would induce increased autoimmunity and concomitant tumor regression. Twenty-three patients started anti–CTLA-4 antibody administration at 3u2009mg/kg and 23 patients started treatment at 5u2009mg/kg, receiving doses every 3 weeks. Patients were dose-escalated every other dose to a maximum of 9u2009mg/kg or until objective clinical responses or grade III/IV autoimmune toxicity were seen. Escalating doses of antibody resulted in proportionally higher plasma concentrations. Sixteen patients (35%) experienced a grade III/IV autoimmune toxicity. Five patients (11%) achieved an objective clinical response. Two of the responses are ongoing at 13 and 16 months, respectively. Flow cytometric analysis of peripheral blood revealed significant increases in both T-cell surface markers of activation and memory phenotype. Thus, higher serum levels and prolonged administration of anti–CTLA-4 antibody resulted in a trend toward a greater incidence of grade III/IV autoimmune toxicity than previously reported, but did not seem to increase objective response rates.

A phase II multicenter study of ipilimumab with or without dacarbazine in chemotherapy-naïve patients with advanced melanoma

SummaryObjective: Ipilimumab is a fully human, anti–cytotoxic T-lymphocyte antigen-4 (CTLA-4) monoclonal antibody that has demonstrated antitumor activity in advanced melanoma. We evaluated the safety and efficacy of ipilimumab alone and in combination with dacarbazine (DTIC) in patients with unresectable, metastatic melanoma. Methods: Chemotherapy-naïve patients were randomized in this multicenter, phase II study to receive ipilimumab at 3xa0mg/kg every 4xa0weeks for four doses either alone or with up to six 5-day courses of DTIC at 250xa0mg/m2/day. The primary efficacy endpoint was objective response rate. Results: Seventy-two patients were treated per-protocol (ipilimumab plus DTIC, nu2009=u200935; ipilimumab, nu2009=u200937). The objective response rate was 14.3% (95% CI, 4.8–30.3) with ipilimumab plus DTIC and was 5.4% (95% CI, 0.7–18.2) with ipilimumab alone. At a median follow-up of 20.9 and 16.4xa0months for ipilimumab plus DTIC (nu2009=u200932) and ipilimumab alone (nu2009=u200932), respectively, median overall survival was 14.3xa0months (95% CI, 10.2–18.8) and 11.4xa0months (95% CI, 6.1–15.6); 12-month, 24-month, and 36-month survival rates were 62%, 24% and 20% for the ipilimumab plus DTIC group and were 45%, 21% and 9% for the ipilimumab alone group, respectively. Immune-related adverse events were, in general, medically manageable and occurred in 65.7% of patients in the combination group versus 53.8% in the monotherapy group, with 17.1% and 7.7% ≥grade 3, respectively. Conclusion: Ipilimumab therapy resulted in clinically meaningful responses in advanced melanoma patients, and the results support further investigations of ipilimumab in combination with DTIC.

A phase II, randomized, double‐blind, placebo‐controlled study evaluating the efficacy and safety of MDX‐1100, a fully human anti‐CXCL10 monoclonal antibody, in combination with methotrexate in patients with rheumatoid arthritis

OBJECTIVEnCXCL10 (also known as interferon-γ-inducible 10-kd protein [IP-10]) is a chemokine that potentially plays a role in the immunopathogenesis of rheumatoid arthritis (RA). We undertook this phase II study to evaluate the efficacy and safety of MDX-1100, a fully human, anti-CXCL10 (anti-IP-10) monoclonal antibody, in RA patients whose disease responded inadequately to methotrexate (MTX).nnnMETHODSnPatients with active RA receiving stable doses of MTX (10-25 mg weekly) were randomized to receive intravenous doses of 10 mg/kg MDX-1100 (n = 35) or placebo (n = 35) every other week. The primary end point was the proportion of patients meeting the American College of Rheumatology 20% improvement criteria (achieving an ACR20 response) on day 85, and patients were followed up for safety to day 141.nnnRESULTSnThe ACR20 response rate was significantly higher among MDX-1100-treated patients than among placebo-treated patients (54% versus 17%; P = 0.0024). Statistically significant differences in the ACR20 response rate between treatments were observed starting on day 43 (P < 0.05). The ACR50 and ACR70 response rates on day 85 did not differ between the groups. Overall, 51.4% of MDX-1100-treated patients and 30.3% of placebo-treated patients experienced at least 1 adverse event (AE). No study drug-related serious AEs were reported.nnnCONCLUSIONnMDX-1100 was well tolerated and demonstrated clinical efficacy in RA patients whose disease responded inadequately to MTX. This is the first study to demonstrate clinical efficacy of a chemokine inhibitor in RA and supports the notion of a potential role of IP-10 in the immunopathogenesis of RA.

Anti-IP-10 antibody (BMS-936557) for ulcerative colitis: a phase II randomised study

Objective Interferon-γ-inducible protein-10 (IP-10 or CXCL10) plays a role in inflammatory cell migration and epithelial cell survival and migration. It is expressed in higher levels in the colonic tissue and plasma of patients with ulcerative colitis (UC). This phase II study assessed the efficacy and safety of BMS-936557, a fully human, monoclonal antibody to IP-10, in the treatment of moderately-to-severely active UC. Design In this 8-week, phase II, double-blind, multicentre, randomised study, patients with active UC received placebo or BMS-936557 (10u2005mg/kg) intravenously every other week. The primary endpoint was the rate of clinical response at Day 57; clinical remission and mucosal healing rates were secondary endpoints. Post hoc analyses evaluated the drug exposure–response relationship and histological improvement. Results 109 patients were included (BMS-936557: n=55; placebo: n=54). Prespecified primary and secondary endpoints were not met; clinical response rate at Day 57 was 52.7% versus 35.2% for BMS-936557 versus placebo (p=0.083), and clinical remission and mucosal healing rates were 18.2% versus 16.7% (p=1.00) and 41.8% versus 35.2% (p=0.556), respectively. However, higher BMS-936557 steady-state trough concentration (Cminss) was associated with increased clinical response (87.5% vs 37.0% (p<0.001) for patients with Cminss 108–235u2005μg/ml vs placebo) and histological improvements (73.0% vs 41.0%; p=0.004). Infections occurred in 7 (12.7%) BMS-936557-treated patients and 3 (5.8%) placebo-treated patients. 2 (3.6%) BMS-936557 patients discontinued due to adverse events. Conclusions Anti-IP-10 antibody, BMS-936557, is a potentially effective therapy for moderately-to-severely active UC. Higher drug exposure correlated with increasing clinical response and histological improvement. Further dose–response studies are warranted. Clinical Trial Registration Number: ClinicalTrials.gov NCT00656890.