Randomized phase II study of the safety and efficacy of a human anti-αv integrin monoclonal antibody (CNTO 95) alone and in combination with dacarbazine in patients with stage IV metastatic melanoma: 12-month results

9029

Objectives: Evaluate the safety and efficacy of CNTO 95, a human anti-αv integrin monoclonal antibody, when administered alone or in combination with dacarbazine (DTIC). Methods: Patients with Stage IV metastatic melanoma were randomized 1:1:1:1 to receive 5 or 10mg/kg CNTO 95 alone, or DTIC (1000mg/m2) + either 10mg/kg CNTO 95 or placebo administered intravenously once every 3 weeks for 8 cycles in the absence of disease progression or unacceptable toxicity. DTIC arms were blinded; single-agent arms were open-label. The primary endpoint was progression free survival (PFS); secondary endpoints included partial response (PR), complete response (CR), stable disease (SD) and overall survival (OS). Major safety endpoints included the incidence of adverse events (AEs) and serious AEs (SAEs). Results: Patients were randomized to receive 5mg/kg CNTO 95 (n=32), 10mg/kg CNTO 95 (n=33), CNTO 95+DTIC (n=32), or placebo+DTIC (n=32). Baseline demographics were similar across groups. The median PFS for CNTO 95+DTIC was 75 days, placebo+DTIC was 54 days and both CNTO 95 alone arms were 42 days. Six patients achieved PR (2–10mg/kg CNTO 95, 1-CNTO 95+DTIC, 3-placebo+DTIC); one patient achieved CR (CNTO 95+DTIC). A higher proportion (43.3%) of patients achieved SD ≥ 12 wks in the CNTO 95+DTIC group compared with the other 3 groups (<20.0%). The median survival was 11.0 months for the patients in the CNTO 95+DTIC arm, 9.8 months and 14.9 months for the 5mg/kg and 10mg/kg arms, and 8.0 months for those in the DTIC control arm. The most common AEs were headache, nausea, fatigue, pyrexia, vomiting and transient uveitic reactions. Three patients (1–5mg/kg, 2-CNTO 95+DTIC) discontinued treatment due to AEs. A higher proportion of patients experienced SAEs in the placebo+DTIC group (29.0%) than in the 5mg/kg (12.9%), 10mg/kg (16.2%) or CNTO 95+DTIC (18.8%) groups. Conclusions: CNTO 95 alone or combined with DTIC was generally well tolerated. In patients with Stage IV metastatic melanoma, a trend toward improvement in PFS, OS and disease control was demonstrated with CNTO 95+DTIC.

Centocor, Centocor Research and Development, Inc.

Centocor Research and Development, Inc.

Johnson & Johnson

Centocor Research and Development, Inc.

No significant financial relationships to disclose.

Evaluation of the effect of systemic corticosteroids for the treatment of immune-related adverse events (irAEs) on the development or maintenance of ipilimumab clinical activity

9037

Background: Ipilimumab, a fully human monoclonal antibody that inhibits cytotoxic T-lymphocyte antigen-4, has clinical activity at 10 mg/kg in patients (pts) with advanced melanoma. Most grade 3/4 immune-related adverse events (irAEs) associated with ipilimumab can be managed with systemic corticosteroids following established treatment guidelines. However, little has been reported about the effects of corticosteroids used to treat irAEs on ipilimumab antitumor responses. Methods: Across 3 phase II studies with 10 mg/kg ipilimumab monotherapy in advanced melanoma (CA184008, 022, and 007; N=283), 83 pts (29.3%) achieved disease control [complete/partial responses (CR/PR), or stable disease (SD) ≥12 weeks] and 43/83 (52%) received steroids for treatment of irAEs. The pts' ability to develop and maintain disease control in the presence and absence of steroids was analyzed. Disease control was assessed by modified World Health Organization (mWHO) criteria and novel immune-related response criteria (irRC) (Hodi FS, et al. J Clin Oncol 26: 2008 [May 20 suppl; abstr 3008]). The range of follow-up was 5.7–6.3 months. Results: Of 117 pts who received steroids prior to response assessment, 26 pts achieved CR or PR, or maintained SD without disease progression by mWHO, and the remaining 91 pts had PD. Of 166 pts who either never received steroids or received them after response assessment, 31 achieved a CR, PR, or SD (by mWHO). Further, of 26 pts with CR/PR by mWHO, 14 received subsequent steroids and 11 maintained a response, while of 12 pts who received no subsequent steroids, 9 maintained a response. Similar results were obtained if irRC were used (see table ). Conclusions: Systemic corticosteroids for treatment of irAEs do not appear to impact the development or maintenance of ipilimumab clinical activity in advanced melanoma.

[Table: see text]

[Table: see text]

Prognostic factors in metastatic melanoma patients treated with biochemotherapy and maintenance immunotherapy

9051

Background: Patients with stage IV metastatic melanoma are usually felt to be incurable with a median survival of 6.4 months and a 5-year survival of only 2%. Biochemotherapy has shown promise with long-term survival in selected patients. We felt the study of prognostic factors would determine which patients might benefit the most from this intensive therapy. Methods: 135 consecutive patients with stage IV melanoma treated with decrescendo biochemotherapy followed by maintenance immunotherapy at one melanoma treatment center were studied to determine the most important prognostic factors; these factors were then validated by analysis of 133 patients treated in a multi-center trial at other institutions. Patients were treated using the inpatient regimen of O'Day (JCO23:710s,2005 abstract). Results: Median overall survival (OS) was 16.6 months with 1-year survival of 70% and 5-year survival of 28%. Median progression-free survival (PFS) was 7.6 months with 15% progression-free at 5 years. PFS curves showed no relapses after 30 months, so remissions were durable. For OS performance status 0, normal LDH, stage M1a, and non-visceral sites of metastases were favorable prognostic factors. For PFS performance status 0, normal LDH, female sex, age <50 and stage M1a were favorable prognostic factors Multivariate analysis demonstrated two important prognostic factors for survival: normal serum LDH and the presence of either skin or nodes as one of the sites of metastatic disease. The group with normal LDH and skin or node metastases had a relatively good prognosis with median survival of 44 months and a 5-year survival of 38%. Conversely patients with elevated LDH without any skin or nodal metastases had a poor prognosis, with no long-term survivors. Conclusions: Metastatic melanoma patients treated with biochemotherapy and maintenance immunotherapy that have either a normal LDH or skin or nodes as one of their metastatic sites may have durable remissions of their disease, and this therapy should be studied further in these groups.

[Table: see text]

Association of peripheral blood absolute lymphocyte count (ALC) and clinical activity in patients (pts) with advanced melanoma treated with ipilimumab

3020

Background: Ipilimumab, an anti-CTLA-4 monoclonal antibody, induces durable survival benefits in advanced melanoma pts. Peripheral ALC from routine safety labs were collected from 533 pts with unresectable stage III/IV malignant melanoma treated with ipilimumab 0.3, 3, or 10 mg/kg (recommended dose) in 4 Phase II studies. Methods: Ipilimumab was given every 3 weeks (Q3W) x 4; eligible pts could then continue to receive ipilimumab Q12W starting at Week 24. ALC was analyzed first in studies CA184007, 008, and 022 combined (ipilimumab 0.3, 3, or 10 mg/kg), and then prospectively analyzed for confirmation in study CA184004 (ipilimumab 3 or 10 mg/kg). Using the modified World Health Organization criteria, Response-evaluable pts (n = 444) were classified by clinical activity (complete or partial response, or stable disease ≥ 24 wks) or without clinical activity. Results: Across studies 007, 008, and 022, pts with clinical activity had a greater mean rate of ALC change (slope) than did pts without clinical activity (P = 0.0013); no pt with a negative ALC slope over the induction period had clinical activity (P = 0.0013) (Table). These associations were confirmed in 004; pts with benefit had a greater mean slope (P = 0.00042), and only 1 pt with a (slightly) negative ALC slope had clinical activity (Table). Over all pts (n = 533), the rate of ALC change was significantly associated with dose (007, 008, 022: P < 0.0001; 004: P = 0.0015). Conclusions: A higher rate of ALC change was associated with clinical activity in a pooled analysis of studies 007, 008, and 022 (n = 379). This was confirmed in study 004 (n = 65). A negative ALC slope was associated with a lack of clinical activity. In both analyses, the rate of change in ALC was dose-dependent, favoring 10 mg/kg.

[Table: see text]

[Table: see text]

Subgroup analysis of efficacy and safety analysis of a randomized, double-blinded controlled phase II study of STA-4783 in combination with paclitaxel in patients with metastatic melanoma

8528

Background: STA-4783 (S), an inducer of heat shock protein 70 (hsp70) is a bis-thiobenzoylhydrazide compound. S leads to up-regulation of hsp70 in tumor cell lines. Xenograft models of solid tumors showed synergistic anti-tumor activity in combination with paclitaxel (P). The combination P + S, in phase I and II studies, showed dose-related hsp70 induction (evidence of biological activity) and tolerability. Methods: Eligibility was based on a diagnosis of metastatic cutaneous melanoma, ECOG <=2, and prior treatment with 1 or no chemotherapy regimens. A total of 81 patients (pts) were randomized 2:1 (P 80 mg/m2 + S 213 mg/m2:P 80 mg/m2) 3 weeks out of 4 at 21 US clinical sites. The primary endpoint was progression free survival (PFS); secondary endpoints were response rate (RR), and adverse events (AEs). Results: Based on intent-to-treat analysis, the median PFS was 3.68 months (m) for P + S vs. 1.84 m in the P only arm (p=.035). RR was 15.1% in the P + S arm and 3.6% in the P arm. Subgroup analysis showed chemo- naive pts (n=23) with P + S showed a median PFS of 8.28 m vs. 2.40 in the P arm (n=9). For pts with 1 prior chemotherapy, (n=29), PFS on P + S was 3.12 m vs. 1.77 m on P (n=19). Of 19 pts who crossed over at progression, data are available for 14. PFS ranged from 0.72 to 5.5 m. Three of the 14 evaluable pts treated with P alone had rapid progression (0.95, 1.6, and 1.7 m) then significant inversion of the time to progression with the addition of S to P (2.3, 5.5, and 4.2 m) suggesting study drug effect. Scans were done at identical intervals (8 weeks). The proportion of pts with AEs of grade 3 or higher was 54% (n=52) in the P + S group and 57% in the P group (n=28); pts on P received a median of 2 cycles, while pts in the P + S group received a median of 4. Adverse events leading to discontinuation were low in both groups: 10% for the P + S, and 14% for P. Conclusions: The addition of S to P showed an increase in PFS vs. P alone particularly in chemo-naïve pts. A few pts failing single agent P appeared to benefit from P + S. Despite the additional treatment duration in the P + S group the drugs were well- tolerated, and showed mainly P related adverse events. A phase III study is planned to confirm a role for P + S in metastatic melanoma.

[Table: see text]

Kinetics of response to ipilimumab (MDX-010) in patients with stage III/IV melanoma

8525

Background: Ipilimumab, a fully human monoclonal antibody that blocks cytotoxic T-lymphocyte antigen-4 (CTLA-4), enhances immune responses to tumor-associated antigens resulting in durable objective responses (OR). This abstract describes the kinetics of response after ipilimumab treatment. Methods: 5 studies (2 complete; 3 ongoing) in 269 treated patients with stage III/IV melanoma were reviewed and analyzed to determine the kinetics and duration of response after ipilimumab. Patients received ipilimumab alone or with dacarbazine, IL-2 or gp100 peptide vaccine. Ipilimumab doses ranged from 0.3–10mg/kg/dose (single or multiple). Complete and partial response (CR, PR), stable and progressive disease (SD, PD) were evaluated. Results: 41 patients (15%) had a confirmed OR at analysis. CR and PR was of late onset in some patients and occurred from ∼10–106 and ∼5–62 weeks (w) post-treatment initiation, respectively. In 28 patients onset of CR or PR occurred after >∼12w of treatment. PD preceded OR (without additional therapy) in 4 patients. In 2 patients, PD measured at ∼6w post-treatment initiation was followed by a PR at ∼12w. In 1 patient the PR changed to a CR at ∼24w and lasted for ∼188w+; the other patient maintained a PR for ∼17w. In the other 2 patients, PD at ∼12w was followed by SD at ∼17–20w and a PR after ∼30 and 62w; PRs in both patients lasted for ∼17 and 40w+, respectively. Duration of OR ranged from ∼6–187w+; ORs are ongoing in 25 patients. Late onset occurred irrespective of dose, regimen and therapeutic partner. Conclusions: Preliminary results suggest that ORs with ipilimumab may be later in onset and more durable than with traditional chemotherapy and may occur after progression. This late onset of effect likely reflects the immune-related mechanism of action of ipilimumab, and suggests that continued treatment/observation may be beneficial despite initial PD or SD. Acknowledgement: Dr. S. Rosenberg

[Table: see text]

Interleukin-2 binds to ganglioside GD(1b)

We have developed a solid matrix immunoassay to determine the binding of interleukin-2 (IL-2) to specific gangliosides. The assay establishes that recombinant human IL-2 binds to ganglioside GD(1b) but not to any other gangliosides (GM(1), GM(2), GM(3), GD(1a), GD(2), GD(3), and GT(1b)). The binding varies with the ratio of GD1b and IL-2. This assay enables distinguishing the nature of the sugar moiety of the ganglioside recognized by IL-2 and establishes the dosimetry of the ganglioside-IL-2 interaction. Since rIL-2 is administered systematically into stage IV melanoma patients, we have examined 45 tumor biopsies for GD(1b) content. The incidence of GD(1b) in tumor biopsies is 51%. We postulate that GD(1b) associated on the tumor or in the circulation of cancer patients may bind to rIL-2 and prevent the availability of rIL-2 to augment antitumor-immune response.

Stereotactic radiosurgery in the treatment of metastatic disease to the brain

We review 190 consecutive patients with 434 metastatic tumors treated by gamma knife stereotactic radiosurgery, from August 1994 to February 1999. Median actuarial survival for all patients was 34 weeks. Factors correlated with significantly improved survival included controlled systemic disease and nonmelanoma histology. We found that no significant survival benefit could be discerned from adjuvant whole brain radiotherapy in this patient group. Survival was not statistically different for patients initially presenting with 1-4 metastases at initial treatment.

Stereotactic radiosurgery in the treatment of metastatic disease to the brain

OBJECTIVE

In recent years, stereotactic radiosurgery has been growing in popularity as a treatment modality for metastatic disease to the brain. The technique has advantages of reduced cost and low morbidity compared with open surgical treatment. Furthermore, it avoids the potential cognitive side effects of fractionated whole-brain radiotherapy. We undertook this study to determine the usefulness of adjuvant radiation therapy and to determine prognostic factors in patients treated with stereotactic radiosurgery.

METHODS

We reviewed our series of patients with metastatic tumors treated using gamma knife stereotactic radiosurgery from August 1994 to February 1999. Nonparametric methods were used to compare treatment subgroups by demographic features including age, Karnofsky Performance Scale score, diagnosis, and systemic disease status. Univariate and multivariate analyses of survival and freedom from progression were performed using Kaplan-Meier and Cox proportional hazards regression techniques.

RESULTS

This study included 190 patients harboring 431 lesions who were treated in 263 treatment sessions. The median follow-up after radiosurgery was 36 weeks for all patients. The median actuarial survival from the time of radiosurgery in all patients was 34 weeks. When patients were stratified according to tumor histology, those without melanoma had a median survival of 39 weeks, and those with melanoma had a median survival of 28 weeks. The cause of death could be determined in 122 (92%) of the patients known to have died during the data capture period. For patients harboring melanoma, death was attributable to systemic disease in 31 (47%), to central nervous system-related processes in 29 (44%), and to unknown causes in 6 (9%). For non-melanoma patients, death was attributable to systemic disease in 45 (68%), to central nervous system-related processes in 17 (26%), and to unknown causes in 4 (6%). Significantly improved survival (P = 0.002) was observed in patients with controlled systemic disease. No significant difference in survival could be ascertained for patients presenting with up to four lesions, although patients with a total tumor volume greater than 9 cc had shortened survival. No survival benefit could be demonstrated for whole-brain radiotherapy administered either concomitantly or after radiosurgery.

CONCLUSION

Factors correlated with significantly improved survival included controlled systemic disease and non-melanoma histology. We found no significant survival benefit that could be discerned from adjuvant whole-brain radiotherapy in this patient group.

A Phase II study of adjuvant therapy with anti-B4-blocked ricin after autologous bone marrow transplantation for patients with relapsed B-cell non-Hodgkin's lymphoma

This Phase II trial was undertaken to determine the safety, toxicity, and potential efficacy of the B-cell restricted immunotoxin anti-B4-blocked ricin (Anti-B4-bR) when administered as adjuvant therapy to patients in complete remission (CR) after autologous bone marrow transplantation (ABMT) for B-cell non-Hodgkin's lymphoma (NHL). Forty-nine patients with B-cell NHL in CR 46-202 days (median, 112 days) post-ABMT received Anti-B4-bR at a dose of 30 microg/kg lean body weight/day for 7 days by continuous i.v. infusion. Patients were eligible for up to two additional courses of therapy at 14-day intervals. A total of 83 courses of Anti-B4-bR were administered, with 31 patients receiving two or more courses of therapy. The mean serum level on day 7 of the first course was 0.77+/-0.41 nM. Reversible toxicities included hepatic transaminase elevations, thrombocytopenia, myalgias, fatigue, nausea, hypoalbuminemia, and dyspnea. Human antimouse antibody (HAMA) and/or human antiricin antibody (HARA) responses occurred in 23 patients at a median of 22 days from the initiation of Anti-B4-bR therapy (range, 11-100 days). The 4-year disease-free survival and overall survival are estimated at 56 and 72%, respectively. Twenty-six patients remain in CR after a median follow-up of 54.5 months. This study demonstrates that Anti-B4-bR can be administered safely to patients as adjuvant therapy early after ABMT for B-cell NHL. The toxicities are tolerable and reversible. Although the early estimate of disease-free survival was very encouraging in this single-armed trial, the 4-year follow-up data demonstrate continued relapse.

Phase II clinical trial of bolus infusion anti-B4 blocked ricin immunoconjugate in patients with relapsed B-cell non-Hodgkin's lymphoma

Immunotoxins, composed of a monoclonal antibody conjugated to a protein toxin, mediate cell death through novel cytotoxic mechanisms. Anti-B4-blocked ricin (anti-B4-bR) recognizes CD19-positive cells, which includes most B-cell non-Hodgkin's lymphomas (NHLs). Previous Phase I clinical studies of anti-B4-bR, using both bolus and continuous dosing regimens, demonstrated no safety or efficacy advantage to the continuous infusion regimen. This Phase II trial in 16 patients with relapsed CD19-positive NHL was conducted to evaluate the efficacy of anti-B4-bR when administered at the previously established maximum tolerated dose using a daily bolus for a 5 consecutive days schedule. Serum pharmacokinetics were measured in selected patients. Tissue samples of involved lymph nodes and bone marrow were also obtained from a portion of patients for determination of anti-B4-bR penetration into tissues. Toxicity was similar to what has been described previously for anti-B4-bR and consisted mainly of reversible elevations of hepatic transaminases and mild to moderate thrombocytopenia. No sustained clinical responses were documented. Pharmacokinetic measurements demonstrated that serum levels compatible with 3 logs of cell kill in vitro could be sustained for several hours in most patients. Immunohistochemical analysis of tissue samples provided some insight into the low efficacy. The immunotoxin could be detected in three of the four bone marrow aspirate samples but in only two of the seven lymph node specimens. Thus, anti-B4-bR, using a single daily bolus for a 5 consecutive day schedule, is not an active agent in relapsed NHL. Poor penetration into certain sites of disease may be one explanation for its lack of efficacy.