Faculty Bibliography

A critical requirement to use tumor antigens as vaccines is that they stimulate CD8+ T cell responses. In this study, we tested the ability of a shed, polyvalent, melanoma antigen vaccine to induce such responses to the melanoma-associated antigens, MAGE-3 and MART-1/Melan-A. Fifteen HLA-A2+ patients with resected malignant melanoma were immunized to the vaccine sc every 2-3 weeks x 4, and monthly thereafter. CD8+ T cells in peripheral blood reacting to HLA-A2 restricted epitopes on MAGE-3 (FLWGPRALV) and/or MART-1/Melan-A (AAGIGILTV) were quantitated directly using a filter spot assay at baseline and following 4 immunizations. Vaccine immunization induced CD8+ T cells reacting specifically to one or both of these antigens in 9 (60%) patients. These cells were CD8+ and HLA-A2 restricted, as reactivity was abrogated by monoclonal antibodies to CD8 and to class I HLA, but not by anti-CD4. The CD8+ T cells were specifically directed to these antigens, as they did not react to the same targets pulsed with a control HLA-A2 restricted peptide recognized by T cells. All responding patients remained recurrence-free during a follow-up of 12-21 months, whereas melanoma recurred within 3-5 months in non-responders. The differences in outcome were unrelated to differences in disease-severity or overall immunological competence between CD8+ T cell responders and non-responders. These results demonstrate that a polyvalent vaccine can stimulate a CD8+ T cell response to MAGE-3 and MART-1/Melan-A in humans, and suggest that the responses are protective and surrogate markers of vaccine efficacy. (C) American Society of Clinical Oncology 1997

PURPOSE: A phase II study of paclitaxel and cisplatin in patients with advanced breast cancer was performed to determine the objective response rate and make further observations about the toxicity of this regimen. PATIENTS AND METHODS: Patients were required to have histologically proven adenocarcinoma of the breast with no more than one chemotherapeutic treatment for advanced disease. Treatment consisted of paclitaxel 200 mg/m2 administered as a 24-hour intravenous (i.v.) infusion followed by cisplatin 75 mg/m2 i.v. Patients received granulocyte colony-stimulating factor (G-CSF) 5 micrograms/kg subcutaneously on day 3 until WBC recovery. Cycles were repeated every 21 days. Patients continued to receive therapy until disease progression or unacceptable toxicity. RESULTS: Forty-four patients entered the trial. Forty-two patients were assessable for response. Nineteen patients (43%) had no prior chemotherapy and 41 had no chemotherapy for metastatic disease. The median number of cycles administered per patient was five (range, one to seven). There were five complete responses (CRs) (11.9%) and 17 partial responses (PRs) (40.5%), with an overall response rate of 52.4% (95% confidence interval [CI], 36.4% to 68.0%). Nine patients had stage III disease. The response rate for this group was 66.7% (95% CI, 33.0% to 92.5%), with three CRs and three PRs. Among 35 patients with stage IV disease, there were two CRs and 14 PRs, with an overall response rate of 48.5% (95% CI, 30.8% to 66.5%). Overall, the median response duration was 10.6 months. Thirty patients (68%) developed transient grade 4 neutropenia. Cumulative neuropathy was the major dose-limiting toxicity. After five cycles of chemotherapy, 96% of patients had at least grade 1 neurotoxicity and 52% had at least grade 2 neurotoxicity. One patient had a toxic death after cycle 1 of therapy. CONCLUSION: The combination of paclitaxel and cisplatin as first-line chemotherapy for women with advanced breast cancer is an active regimen. However, the cumulative neurotoxicity was significant and dose-limiting in the majority of patients

Topotecan, a topoisomerase-1 inhibitor, may have greater therapeutic index when given by prolonged infusion. In an earlier phase I trial of escalating low-dose infusion (MTD = 0.53 mg/m2/d x 21d) for previously treated pts (JCO; 12:553 1994), 3/6 heavily treated ovarian cancer pts responded. We administered 60 cycles of TPT to 16 pts in a phase II study starting at 0.4 mg/m2/d x 21 days. All pts had one prior platinum-containing chemotherapy regimen with progression or recurrence (early less than 6 mo vs later). All pts had PS 0-1, normal heme parameters and Creat less than 1.6. Measurable disease (greater than 2 cm on CT scan) was required. Four pts were able to be escalated to 0.5 mg/m2/d for 11 cycles and 6 were reduced to 0.3 in 15 cycles. Responses are presented in a table. Four pts had stable disease (3 still on rx), and 6 PD. Overall response rate is at least 37% (95% CI =12-62%). Hematologic toxicity included leukopenia and neutropenia gr 3 = 4 pts (7%) and gr 4 = 1 pt (2%) but no grade 3 or 4 thrombopenia. Eight pts required blood transfusions. Non-heme toxicity included grade 1 nausea = 7 pts and gr 2 =3 pts; grade 1 fatigue =5 and gr 1 alopecia = 4 pts. Two catheter related thromboses occurred; 2 had sepsis. Weekly PBMC topo-1 levels were obtained for pharmacodynamic studies (abstract submitted). This response rate is among the highest reported for second-line therapy of ovarian cancer and is seen in both platinum resistant and refractory disease. Data on these and additional pts currently being accrued will be presented. (C) American Society of Clinical Oncology 1997

The identification of effective adjuvants is critical for tumor vaccine development. Towards this end, we examined whether the immunogenicity of a melanoma vaccine could be potentiated by DETOX, an adjuvant consisting of monophosphoryl lipid A (MPL) and purified mycobacterial cell-wall skeleton (CWS). Nineteen patients with resected stage III melanoma were immunized with a polyvalent melanoma antigen vaccine (40 micrograms) admixed with DETOX, q3 wks x 4. Seven patients received vaccine + low-dose DETOX (10 micrograms MPL + 100 micrograms CWS) and 12 received vaccine + high-dose DETOX (20 micrograms MPL + 200 micrograms CWS). A non-randomized control group of 35 patients was treated similarly with 40 micrograms vaccine + alum. One week after the fourth vaccine immunization, melanoma antibodies were increased over baseline in 7/7 (100%) patients treated with vaccine + low-dose DETOX, 8/12 (67%) patients treated with vaccine + high-dose DETOX, and in 4/19 (21%) of vaccine + alum patients. For the entire DETOX group, the antibody response rate was 15/19 (79%) compared 4/19 (21%) in the alum group (p < 0.001). In contrast, a strong delayed-type hypersensitivity (DTH) response (> or = 15 mm increase in DTH response over baseline) was induced in 50% of the entire DETOX group versus in 47% of the alum group. Median disease-free (DF) survival for the entire DETOX group was 17.8 months compared with 32.1 months in the alum group (p < 0.05). In conclusion, DETOX markedly potentiated antibody but had little effect on DTH responses to melanoma vaccine immunization. It did not appear to improve disease-free survival in comparison to alum in this non-randomized study

BACKGROUND. Melanoma vaccine treatment appears to slow the progression of melanoma in some patients, particularly in patients in whom it stimulates cellular antimelanoma immune responses. The relationship of vaccine-induced antibody responses to clinical outcome is less clear. The purpose of this study was to investigate the clinical relevance of antibody responses to melanoma vaccine immunization. METHODS. Eighty-two evaluable patients with surgically resected American Joint Committee on Cancer Stage III malignant melanoma were immunized to a partially purified, polyvalent, melanoma antigen vaccine. Antimelanoma antibodies were measured by immunoprecipitation and sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis before vaccine treatment and 1 week after the fourth immunization. RESULTS. Vaccine treatment induced or augmented antibody responses to melanoma in 32 (39%) of the patients. The antibodies were directed to one or more antigens of 38-43, 75, 110, 150 and/or 210 kDs, which previously have been shown to be expressed preferentially in cultured human melanoma cells. The median disease free survival of patients with a vaccine-induced antibody response to one or more of these antigens was 5.4 years compared with 1.4 years for nonresponders (P = 0.06), and 5-year overall survival was 71% compared with 44%, respectively (P = < 0.01). As determined by Cox multivariate analysis, the difference in overall survival was independent of disease severity or of immunologic competence as evaluated by ability to be sensitized to dinitrochlorobenzene. The difference in survival between antibody responders and nonresponders improved with time. CONCLUSIONS. The antibody response to vaccine treatment is an immune marker of vaccine activity that appears to be predictive of a later reduction in the recurrence of melanoma and is unrelated to the vaccine's ability to induce cellular immune responses. This finding suggests that vaccine treatment may be effective in slowing the progression of melanoma in some patients and that the protective effect is mediated partly by vaccine-induced antimelanoma antibodies

Alpha interferon (IFN) has single agent activity in the treatment of metastatic malignant melanoma. Preclinical data suggests that cis-retinoic acid (cRA) may potentiate the activity of IFN. Clinical trials of this combination in the treatment of squamous cell carcinoma report higher response rates than that expected for IFN alone. We tested the activity of the combination of IFN and cRA in patients (pts) with metastatic malignant melanoma. 13 pts were treated with IFN 5 x 10 (6) units/m2 tiw and cRA 100 mg/kg/day. 11 pts were previously treated with chemotherapy; 2 had no prior treatment. Sites of metastases include: lung (9), liver (4), soft tissue (7), adrenals (2) nodes (2). 1 PR was seen in lung and adrenal mets (for 6 mo), 2 pts had stabilization of pulmonary mets for 2 mo. All other pts had progressive disease within 8 wk of beginning treatment. Toxicity was substantial. All pts experienced ECOG Grade 1-2 fatigue, myalgias, anorexia, stomatitis and cheilitis. Serum cholesterol and triglycerides became elevated in all pts. Dose reductions included: 1 pt 50% IFN for fatigue, 1 pt 50% cRA for stomatitis, 3 pts 50% cRA for hypertriglyceridemia. 1 pt discontinued therapy for decline in PS to ECOG Level 3. The mean duration of treatment was 8.8 wk; range (3 -28 wk). The combination of cRA and IFN in this study did not demonstrate any improvement over the single agent activity of IFN. (C) American Society of Clinical Oncology 1997

EDA is an analog of methotrexate which has clinical activity in a variety of solid tumors. We are studying EDA in combination with DOX to assess the toxicities and the maximally tolerated dose (MTD). Without G-CSF, the MTD was EDA 40 mg/m2 iv q 2 wk and DOX 30 mg/m2 iv q 4 wk. A 25% dose-escalation of both drugs resulted in dose-limiting neutropenia in 3/6 evaluable patients. Subsequently, G-CSF was added to the regimen on days 3-13. In addition, all patients received ice chip cryotherapy with EDA infusion. After these modifications, 6 patients (M/F; 5/1) have entered the trial. Median age 53 (range 44-61); median PS of 1. All had prior chemotherapy (2 greater than or equal to 2 regimens); 3 prior radiation. A total of 19 cycles were given. There were no significant toxicities noted during cycle 1 of chemotherapy with EDA 50 mg/m2 and DOX 37 mg/m2 + G-CSF. One patient developed grade 1 mucositis after cycle 4 requiring dose reduction and subsequent elimination of day 15 EDA. Despite this, he developed grade 3 mucositis and grade 4 neutropenia after cycle 7 requiring day 1 dose reduction of both EDA and DOX. Three patients have received at least 1 cycle of chemotherapy with EDA 62 mg/m2 and DOX 47 mg/m2 + G-CSF. There were no significant toxicities identified. The doses of both EDA and DOX can be escalated by the addition of G-CSF. Ice chip cryotherapy appears to reduce the severity of mucositis with this regimen. Dose escalation is continuing. Phase II studies are planned in soft tissue sarcoma and colon cancer. (C) American Society of Clinical Oncology 1997

R24, a murine monoclonal antibody, has been shown to mediate complement- and antibody-dependent cellular cytotoxicity (ADCC) of melanoma tumor targets. We conducted a Phase Ib clinical trial using granulocyte-macrophage colony-stimulating factor (GM-CSF) and R24 in 20 patients with metastatic melanoma. The purpose of this study was to test the hypothesis that treatment with GM-CSF could up-regulate monocyte and granulocyte ADCC and that the combination of GM-CSF plus R24, which mediates ADCC, would lead to enhanced anti-tumor activity in patients with melanoma. GM-CSF was administered by subcutaneous injection daily for 21 days at a dose of 150 micrograms/m2/day. R24 was administered by continuous intravenous infusion on days 8-15 at three dose levels: 0, 10, and 50 mg/m2/day. All 20 patients received one cycle of treatment only. Immune parameters measured were monocyte and granulocyte direct cytotoxicity and ADCC. All patients were evaluable for toxicity. Fifteen patients were evaluable for immune response. Treatment with GM-CSF alone was well tolerated. Toxicity from the combination of GM-CSF plus R24 included diffuse urticaria, nausea and vomiting, hypertension, and hypotension. Hypotension was the dose-limiting toxicity. Two patients on the 50-mg/m2/day dose level of R24 achieved a partial response lasting 2+ and 5+ months. Treatment with GM-CSF led to a statistically significant enhancement of monocyte and granulocyte direct cytotoxicity and ADCC. The maximally tolerated dose of R24 given at this schedule combined with GM-CSF is < 50 mg/m2/day. We conclude that GM-CSF given by subcutaneous injection at 150 micrograms/m2 x 21 days can enhance effector cell ADCC and direct cytotoxicity and that the combination of GM-CSF and R24 can be therapeutic