Early on-treatment assessment of T-cells, cytokines and tumor DNA with adaptively-dosed nivolumab + ipilimumab: final results from the phase 2 ADAPT-IT study.

PURPOSE: ADAPT-IT (NCT03122522) investigated adaptive ipilimumab discontinuation in melanoma based on early radiographic assessment. Initial findings indicated similar effectiveness compared to conventional nivolumab-ipilimumab (nivo-ipi). Exploratory biomarker analyses and final clinical results are now reported. PATIENTS AND METHODS: Patients with unresectable melanoma received two doses of nivo-ipi. Radiographic assessment at Week 6 informed continuation of ipilimumab before nivolumab maintenance. The primary endpoint was overall response rate (ORR) at Week 12. Plasma was assayed for circulating tumor DNA (ctDNA) and ten cytokines using a multiplex immunoassay. Flow cytometry of peripheral blood mononuclear cells was performed with an 11-color panel. RESULTS: Among treated patients, expansion of proliferating T-cell populations was observed in both responders and non-responders. Baseline IL-6 levels were lower in patients achieving an objective radiographic response (median 1.30 vs 2.86 pg/mL; p=0.025). Higher baseline IL-6 levels were associated with shorter progression-freesurvival (PFS; hazard ratio (HR)=1.24, 95% CI:1.01-1.52; p=0.041). At Week 6, patients with response had lower average tumor variant allele fractions (VAF) compared to non-responders (median 0.000 v 0.019; p=0.014). Greater increases in average VAF from baseline to Week 6 correlated with shorter PFS (HR=1.11, 95% CI:1.01-1.21; p=0.023). Week 12 ORR was 47% (95% CI:35-59%) with a median follow-up of 34 months among survivors. Median PFS was 21 months (95% CI:10-not reached); 76% of responses (95% CI:64%-91%) persisted at 36 months. CONCLUSIONS: Adaptively dosed nivo-ipi responses are durable and resemble historical data for conventional nivo-ipi. Baseline IL-6 and ctDNA changes during treatment warrant further study as biomarkers of nivo-ipi response.

Interplay of Immunosuppression and Immunotherapy Among Patients With Cancer and COVID-19.

Importance: Cytokine storm due to COVID-19 can cause high morbidity and mortality and may be more common in patients with cancer treated with immunotherapy (IO) due to immune system activation. Objective: To determine the association of baseline immunosuppression and/or IO-based therapies with COVID-19 severity and cytokine storm in patients with cancer. Design, Setting, and Participants: This registry-based retrospective cohort study included 12 046 patients reported to the COVID-19 and Cancer Consortium (CCC19) registry from March 2020 to May 2022. The CCC19 registry is a centralized international multi-institutional registry of patients with COVID-19 with a current or past diagnosis of cancer. Records analyzed included patients with active or previous cancer who had a laboratory-confirmed infection with SARS-CoV-2 by polymerase chain reaction and/or serologic findings. Exposures: Immunosuppression due to therapy; systemic anticancer therapy (IO or non-IO). Main Outcomes and Measures: The primary outcome was a 5-level ordinal scale of COVID-19 severity: no complications; hospitalized without requiring oxygen; hospitalized and required oxygen; intensive care unit admission and/or mechanical ventilation; death. The secondary outcome was the occurrence of cytokine storm. Results: The median age of the entire cohort was 65 years (interquartile range [IQR], 54-74) years and 6359 patients were female (52.8%) and 6598 (54.8%) were non-Hispanic White. A total of 599 (5.0%) patients received IO, whereas 4327 (35.9%) received non-IO systemic anticancer therapies, and 7120 (59.1%) did not receive any antineoplastic regimen within 3 months prior to COVID-19 diagnosis. Although no difference in COVID-19 severity and cytokine storm was found in the IO group compared with the untreated group in the total cohort (adjusted odds ratio [aOR], 0.80; 95% CI, 0.56-1.13, and aOR, 0.89; 95% CI, 0.41-1.93, respectively), patients with baseline immunosuppression treated with IO (vs untreated) had worse COVID-19 severity and cytokine storm (aOR, 3.33; 95% CI, 1.38-8.01, and aOR, 4.41; 95% CI, 1.71-11.38, respectively). Patients with immunosuppression receiving non-IO therapies (vs untreated) also had worse COVID-19 severity (aOR, 1.79; 95% CI, 1.36-2.35) and cytokine storm (aOR, 2.32; 95% CI, 1.42-3.79). Conclusions and Relevance: This cohort study found that in patients with cancer and COVID-19, administration of systemic anticancer therapies, especially IO, in the context of baseline immunosuppression was associated with severe clinical outcomes and the development of cytokine storm. Trial Registration: ClinicalTrials.gov Identifier: NCT04354701.

Adaptive Dosing of Nivolumab + Ipilimumab Immunotherapy Based Upon Early, Interim Radiographic Assessment in Advanced Melanoma (The ADAPT-IT Study).

PURPOSE: Nivolumab + ipilimumab (nivo + ipi) is highly efficacious but has high toxicity. Standard treatment in advanced melanoma is four doses of nivo + ipi followed by nivo alone. Whether four doses of nivo + ipi are needed is unclear. METHODS: The Adaptively Dosed ImmunoTherapy Trial (ADAPT-IT) study (NCT03122522) is a multicenter, single-arm phase II clinical trial. Patients received two doses of nivo (1 mg/kg) + ipi (3 mg/kg) followed by a computed tomography scan at week 6. Patients without new lesions or index lesion tumor growth of > 4% had protocol-defined early favorable antitumor effect (FATE) and ceased nivo + ipi, transitioning to nivo monotherapy. Patients without FATE at week 6 received the standard third and fourth doses of nivo + ipi followed by nivo monotherapy. The primary end point was response rate by RECIST 1.1 at week 12. Secondary end points included additional efficacy assessments and safety. RESULTS: Sixty patients were enrolled; 41 patients (68%) had FATE at week 6 and met criteria for stopping nivo + ipi. Best overall response rates by RECIST at week 12 or any time afterward were 48% (95% CI, 35 to 62) and 58% (95% CI, 45 to 71), respectively. With a median follow-up of 25 months, the estimated 18-month progression-free survival and overall survival are 52% and 80%, respectively. Fifty seven percent of patients had grade 3-5 treatment-related toxicity. CONCLUSION: The efficacy and toxicity of standard four dose nivo + ipi induction therapy in melanoma is likely driven by the first two doses. An interim computed tomography scan after two doses guided cessation of combination dosing and identified almost all responders. Longer follow-up and further study are needed to fully understand the implications of a shortened induction course of nivo + ipi.

Combining Panitumumab With Anti-PD-1 Antibody in Cutaneous Squamous Cell Carcinoma of the Head and Neck After Inadequate Response to Anti-PD-1 Antibody Alone.

Anti-epidermal growth factor receptor (EGFR) antibodies and anti-programmed cell death 1 protein (PD-1) antibodies have been used separately to treat metastatic cutaneous squamous cell carcinoma (cSCC). While two anti-EGFR antibodies have similar clinical activity, cetuximab is administered weekly, whereas panitumumab is administered every two weeks. This report details findings using panitumumab in combination with anti-PD-1 antibody in patients with relapsed refractory cSCC. Three consecutive patients with poor performance status and rapidly progressive recurrent cutaneous squamous cell carcinoma (cSCC) of the face or scalp signed informed consent to receive an anti-PD-1 antibody with the option to add panitumumab were there inadequate response. After 2, 5, and 7 cycles of anti-PD-1 antibody treatment, respectively, panitumumab was added and the combination was continued for 27, 7, and 5 cycles, respectively. Fatigue, rash, and hypomagnesemia were reported, consistent with expectations for either agent alone. All three patients achieved durable complete response. The favorable clinical outcomes support further evaluation of the combination of anti-PD1 and anti-EGFR antibodies to control refractory cSCC of the face or scalp. J Drugs Dermatol. 2021;20(8):901-904. doi:10.36849/JDD.6175.

Challenges in assessing the clinical utility and economic value of immune checkpoint inhibitor therapies of Cancer.

Advances in the immunotherapy of cancer have prolonged survival for cancer patients, but the clinical and financial impact of treatments must be considered in determining the overall clinical utility and economic value of therapeutic agents. Quality-adjusted life years and incremental cost-effectiveness ratios are clinical and economic metrics that can be used to evaluate the value of immune checkpoint inhibitors. This Commentary provides perspective on the limitations, benefits, and potential enhancement of this approach to support value-based medicine.

Intermittent Dosing of Dabrafenib and Trametinib in Metastatic BRAFV600E Mutated Papillary Thyroid Cancer: Two Case Reports.

BACKGROUND: A multi-institutional, randomized phase II trial of continuous dosing of dabrafenib with or without trametinib is ongoing in metastatic thyroid cancer. Preclinical evidence and emerging clinical experience in other cancers support evaluating intermittent dosing of these two agents to achieve more durable response, while being better tolerated and more cost effective. PATIENTS: Two consecutive patients with symptomatic, metastatic radioactive iodine-resistant BRAFV600E mutated papillary thyroid cancer and poor performance status were treated initially with dabrafenib 150 mg twice daily plus trametinib 2 mg once daily, first in continuous daily dosing, then in a five-week-on and three-week-off schedule. RESULTS: Both patients showed rapid clinical improvement upon starting the regimen. They also noted improved tolerance of treatment upon transitioning to the intermittent dosing schedule. They continue to show evidence of antitumor activity 27 and 18 months respectively from the start of treatment and 15 and 13 months respectively from the start of the first break using intermittent dosing. CONCLUSIONS: Achieving durable palliation in these consecutive patients supports evaluating the intermittent dosing schedule of dabrafenib and trametinib in BRAFV600E mutated papillary thyroid cancer. Results of the ongoing phase 3 trial of continuous daily dosing and a subsequent trial of intermittent dosing, as is being tested in other cancers, will be needed to confirm that an intermittent dosing strategy in thyroid cancer can forestall resistant disease, improve tolerability, and decrease the cost of care.

Melanoma brain metastasis: overview of current management and emerging targeted therapies.

The high rate of brain metastasis in patients with advanced melanoma has been a clinical challenge for oncologists. Despite considerable progress made in the management of advanced melanoma over the past two decades, improvement in overall survival has been elusive. This is due to the high incidence of CNS metastases, which progress relentlessly and which are only anecdotally responsive to systemic therapies. Surgery, stereotactic radiosurgery and whole-brain radiotherapy with or without cytotoxic chemotherapy remain the mainstay of treatment. However, new drugs have been developed based on our improved understanding of the molecular signaling mechanisms responsible for host immune tolerance and for melanoma growth. In 2011, the US FDA approved two agents, one antagonizing each of these processes, for the treatment of advanced melanoma. The first is ipilimumab, an anti-CTLA-4 monoclonal antibody that enhances cellular immunity and reduces tolerance to tumor-associated antigens. The second is vemurafenib, an inhibitor that blocks the abnormal signaling for melanoma cellular growth in tumors that carry the BRAF(V600E) mutation. Both drugs have anecdotal clinical activity for brain metastasis and are being evaluated in clinical trial settings. Additional clinical trials of newer agents involving these pathways are also showing promise. Therefore, targeted therapies must be incorporated into the multimodality management of melanoma brain metastasis.

Phase 1 study of MLN8054, a selective inhibitor of Aurora A kinase in patients with advanced solid tumors.

PURPOSE: Aurora A kinase is critical in assembly and function of the mitotic spindle. It is overexpressed in various tumor types and implicated in oncogenesis and tumor progression. This trial evaluated the dose-limiting toxicities (DLTs) and maximum tolerated dose (MTD) of MLN8054, a selective small-molecule inhibitor of Aurora A kinase. METHODS: In this first-in-human, dose-escalation study, MLN8054 was given orally for 7, 14, or 21 days followed by a 14-day treatment-free period. Escalating cohorts of 3-6 patients with advanced solid tumors were treated until DLT was seen in ≥2 patients in a cohort. Serial blood samples were collected for pharmacokinetics and skin biopsies were collected for pharmacodynamics. RESULTS: Sixty-one patients received 5, 10, 20, 30, or 40 mg once daily for 7 days; 25, 35, 45, or 55 mg/day in four divided doses (QID) for 7 days; or 55, 60, 70, or 80 mg/day plus methylphenidate or modafinil with daytime doses (QID/M) for 7-21 days. DLTs of reversible grade 3 benzodiazepine-like effects defined the estimated MTD of 60 mg QID/M for 14 days. MLN8054 was absorbed rapidly, exposure was dose proportional, and terminal half-life was 30-40 h. Three patients had stable disease for >6 cycles. CONCLUSIONS: MLN8054 dosing for up to 14 days of a 28-day cycle was feasible. Reversible somnolence was dose limiting and prevented achievement of plasma concentrations predicted necessary for target modulation. A recommended dose for investigation in phase 2 trials was not established. A second-generation Aurora A kinase inhibitor is in development.

Phase I study of the selective Aurora A kinase inhibitor MLN8054 in patients with advanced solid tumors: safety, pharmacokinetics, and pharmacodynamics.

This phase I trial examined the safety, pharmacokinetics, and pharmacodynamics of MLN8054, an oral, selective, small-molecule inhibitor of Aurora A kinase. Patients with advanced solid tumors received increasing doses of MLN8054 in 28-day cycles until dose-limiting toxicity (DLT) was seen in ≥2 of 3-6 patients in a cohort. For the 10-mg and 20-mg cohorts, treatment was administered once daily on days 1 to 5 and 8 to 12. Patients in later cohorts (25, 35, 45, 55, 60, 70, and 80 mg/day) were treated four times daily on days 1 to 14, with the largest dose at bedtime (QID-14D) to mitigate benzodiazepine-like effects possibly associated with peak plasma concentrations. Patients (n = 43) received a median of 1 cycle (range, 1-10). DLT of somnolence was first noted in the 20-mg cohort. Two DLTs of somnolence (n = 1) and transaminitis (n = 1) were seen at QID-14D 80 mg. Grade 2 oral mucositis (n = 1), predicted to be a mechanistic effect, was observed only at QID-14D 80 mg. MLN8054 exposure levels were roughly linear with dose; terminal half-life was 30 to 40 hours. Pharmacodynamic analyses of skin and tumor mitotic indices, mitotic cell chromosome alignment, and spindle bipolarity provided evidence of Aurora A inhibition. MLN8054 dosing for 10 to 14 days in 28-day cycles was feasible. Somnolence and transaminitis were DLTs. Pharmacodynamic analyses in mitotic cells of both skin and tumor provided proof of mechanism for Aurora A kinase inhibition. A more potent, selective, second-generation Aurora A kinase inhibitor, MLN8237, is in clinical development.

Autologous tumor-derived heat-shock protein peptide complex-96 (HSPPC-96) in patients with metastatic melanoma.

BACKGROUND: Glycoprotein-96, a non-polymorphic heat-shock protein, associates with intracellular peptides. Autologous tumor-derived heat shock protein-peptide complex 96 (HSPPC-96) can elicit potent tumor-specific T cell responses and protective immunity in animal models. We sought to investigate the feasibility, safety, and antitumor activity of HSPPC-96 vaccines prepared from tumor specimens of patients with metastatic melanoma. METHODS: Patients with a Karnofsky Performance Status >70% and stage III or stage IV melanoma had to have a metastasis >3 cm in diameter resectable as part of routine clinical management. HSPPC-96 tumor-derived vaccines were prepared in one of three dose levels (2.5, 25, or 100 microg/dose) and administered as an intradermal injection weekly for 4 consecutive weeks. In vivo induction of immunity was evaluated using delayed-type hypersensitivity (DTH) to HSPPC-96, irradiated tumor, and dinitrochlorobenzene (DNCB). The gamma-interferon (IFNgamma) ELISPOT assay was used to measure induction of a peripheral blood mononuclear cell response against autologous tumor cells at baseline and at the beginning of weeks 3, 4, and 8. RESULTS: Among 36 patients enrolled, 72% had stage IV melanoma and 83% had received prior systemic therapy. The smallest tumor specimen from which HSPPC-96 was prepared weighed 2 g. Twelve patients (including 9 with stage IV and indicator lesions) had a negative DNCB skin test result at baseline. All 36 patients were treated and evaluable for toxicity and response. There were no serious toxicities. There were no observed DTH responses to HSPPC-96 or to autologous tumor cells before or during treatment. The IFNgamma-producing cell count rose modestly in 5 of 26 patients and returned to baseline by week 8, with no discernible association with HSPPC-96 dosing or clinical parameters. There were no objective responses among 16 patients with stage IV disease and indicator lesions. Among 20 patients treated in the adjuvant setting, 11 with stage IV melanoma at baseline had a progression-free and overall survival of 45% and 82%, respectively, with a median follow-up of 10 years. CONCLUSION: Treatment with autologous tumor-derived HSPPC-96 was feasible and safe at all doses tested. Observed immunological effects and antitumor activity were modest, precluding selection of a biologically active dose. Nevertheless, the 25-microg dose level was shown to be practical for further study.

A randomized phase 2 study of erlotinib alone and in combination with bortezomib in previously treated advanced non-small cell lung cancer.

INTRODUCTION: This phase 2 study was conducted to determine the efficacy and safety of erlotinib alone and with bortezomib in patients with non-small cell lung cancer (NSCLC). METHODS: Patients with histologically or cytologically confirmed relapsed or refractory stage IIIb/IV NSCLC were randomized (1:1; stratified by baseline histology, smoking history, sex) to receive erlotinib 150 mg/d alone (arm A; n = 25) or in combination with bortezomib 1.6 mg/m2, days 1 and 8 (arm B; n = 25) in 21-day cycles. Responses were assessed using Response Evaluation Criteria in Solid Tumors. Tumor samples were evaluated for mutations predicting response. Six additional patients received the combination in a prior dose deescalation stage and were included in safety analyses. RESULTS: Response rates were 16% in arm A and 9% in arm B; disease control rates were 52 and 45%, respectively. The study was halted at the planned interim analysis due to insufficient clinical activity in arm B. Median progression-free survival and overall survival were 2.7 and 7.3 months in arm A, and 1.3 and 8.5 months in arm B. Six-month survival rates were 56.0% in both arms; 12-month rates were 40 and 30% in arms A and B, respectively. Response rate to erlotinib+/-bortezomib was significantly higher in patients with epidermal growth factor receptor mutations (50 versus 9% for wild type). The most common treatment-related grade > or =3 adverse event was skin rash (three patients in each treatment group). CONCLUSION: Insufficient activity was seen with erlotinib plus bortezomib in patients with relapsed/refractory advanced NSCLC to warrant a phase 3 study of the combination.

A randomized phase III trial of biochemotherapy versus interferon-alpha-2b for adjuvant therapy in patients at high risk for melanoma recurrence.

The objective of this study was to compare the clinical benefit of biochemotherapy and interferon-alpha-2b (IFN) as adjuvant therapy. Biochemotherapy has higher response rates than other regimens in patients with metastatic melanoma. We conducted a randomized phase III study comparing the clinical benefit of biochemotherapy and IFN as adjuvant therapy. Patients who had undergone lymphadenectomy for melanoma metastatic to regional lymph nodes were randomly assigned to either biochemotherapy or IFN, and IFN patients were further randomized to either high-dose IFN (HDI) or intermediate-dose IFN (IDI). The primary end point was relapse-free survival (RFS); the secondary end point was overall survival (OS). The planned enrollment was 200 patients, the number required to have 80% power to detect, at a significance level of 5%, an improvement in median RFS from 18 to 36 months and an improvement in median OS from 40 to 80 months between the IFN and biochemotherapy groups. A futility analysis was performed because of slow accrual. One hundred and thirty-eight patients were enrolled - 71 in the biochemotherapy group, 34 in the HDI subgroup, and 33 in the IDI subgroup. No significant differences in median RFS or OS between the HDI and IDI subgroups were observed. With a median follow-up of 49.3 months, neither the biochemotherapy nor IFN group had reached median RFS or OS, and there were no significant differences in estimated median RFS or OS (P=0.86 and 0.45, respectively) between the two groups. Biochemotherapy is not more effective than IFN as adjuvant therapy for melanoma. These findings support early termination of this trial.

Changes in pERK1/2 and pAKT expression in melanoma lesions after imatinib treatment.

Response to treatment with imatinib mesylate has been associated in preclinical models with the inhibition of two signaling pathways that promote cellular survival - the phosphatidylinositol 3-kinase/AKT pathway and the mitogen-activated protein kinase/extracellular signal-regulated kinase (ERK) pathway. We sought to evaluate the extent of inhibition of these two pathways in metastatic melanoma specimens from patients treated with imatinib. Metastatic melanoma tumor samples were obtained before and during the second week of imatinib treatment from patients enrolled in a phase II study. A tissue microarray was constructed using formalin-fixed, paraffin-embedded tissues, and immunohistochemical analysis was performed using standard techniques to detect phosphorylated (p) ERK1/2 and pAKT expression. Of 21 patients who were treated with imatinib, tumor samples adequate for analysis were available both at baseline and during the second week of treatment from 10 patients for pERK1/2 expression and from nine patients for pAKT expression. No consistent pattern of change in pAKT or pERK expression after treatment with imatinib was observed. No apparent correlation between the clinical benefit of imatinib treatment and changes in pAKT and pERK1/2 expression was observed. A better understanding of the AKT and mitogen-activated protein kinase pathways is needed to optimize the clinical benefit of targeted therapy, such as imatinib.

Analysis of protein tyrosine kinases expression in the melanoma metastases of patients treated with Imatinib Mesylate (STI571, Gleevec).

BACKGROUND: Protein tyrosine kinase (PTK) inhibition has been identified as a promising strategy in the development of new selective therapies, targeting the signaling pathways in melanoma progression. Gleevec, a novel class of anti-tumor drugs, may have a potential therapeutic benefit in melanoma, which involves abnormal activation of abl, c-kit, and platelet-derived growth factor (PDGF) tyrosine kinases. METHODS: Tumor biopsies from 13 patients with metastatic melanoma were screened by immunohistochemistry for PTK [c-kit, C-abl, Abl-related gene (ARG), PDGF receptor-alpha (PDGFR-alpha) and PDGFR-beta] expression before and after being treated with Gleevec @ 400 mg bid for 2 weeks. Both, percentage of positive cells and staining intensity were evaluated. RESULTS: We found a statistically significant (p < 0.01) selective loss of PTK expression in the follow-up biopsy, both in intensity and number of positive cells. PDGFR-alpha and -beta had the highest level of expression reduction. One patient had a durable clinical response, and the follow-up biopsy showed negative expression for four of the PTKs, namely c-abl, ARG, PDGFR-alpha, and beta. CONCLUSIONS: Our study reports for the first time the in vivo effect of Gleevec in the induction of apparently selective reduction of PTKs expression under anti-tyrosine kinases treatment, suggesting its potential role in melanoma treatment.

Multicenter Phase II trial of high-dose imatinib mesylate in metastatic melanoma: significant toxicity with no clinical efficacy.

BACKGROUND: Systemic treatment of metastatic melanoma is largely ineffective and alternative approaches are needed. Imatinib mesylate is an oral tyrosine kinase inhibitor that targets bcr-Abl, c-kit, platelet-derived growth factor receptor (PDGFR)-alpha, and PDGFR-beta, leading to remarkable clinical responses in several cancers. Signal transduction via c-kit, PDGFR-alpha, and PDGFR-beta has been demonstrated in malignant melanoma. METHODS: The primary objective of this Phase II study was to determine the response rate, response duration, and the frequency of 6-month progression-free survival in patients who could receive up to 2 prior therapeutic regimens. Initially, patients received imatinib at at dose of 400 mg twice orally each day. Based on Simon's optimal design, the study allowed entry of 21 patients; if there were > or = 2 objective responses, accrual would then continue to a total of 41 patients. RESULTS: Twenty-six patients were enrolled. Patients experienced 29 episodes of Grade 3 and 2 episodes of Grade 4 toxicity (according to National Cancer Institute common toxicity criteria). No objective clinical responses were noted among the 25 evaluable patients. The median time to progression was 54 days and the median overall survival was 200 days. No patient was free of disease progression at 6 months. Paraffin-embedded tumor specimens from 15 patients were tested for expression of imatinib responsive kinases by immunohistochemistry. Three tumors had moderate and 5 tumors had weak staining for c-kit. Five tumor samples had weak staining for PDGFR-alpha and -beta. CONCLUSIONS: Imatinib is an inactive single agent in metastatic melanoma in a population of predominantely pretreated patients. The levels of c-kit and/or PDGFR-alpha, -beta expression in the current study were lower than previously reported. Alternative treatment strategies remain a priority for patients with advanced melanoma.

Pilot study of high-dose, concurrent biochemotherapy for advanced melanoma.

BACKGROUND: Durable complete response rates ranging from 5% to 20% have been reported in association with biochemotherapy for patients with metastatic melanoma, with response rates on the low end of this range being observed in trials that used lower doses and less intense treatment schedules. In the current study, the authors addressed the feasibility of increasing the doses of agents used in concurrent biochemotherapy. METHODS: Three patients with metastatic melanoma were enrolled at each of six concurrent biochemotherapy dose levels. The doses were as follows: dacarbazine 800 mg/m(2) or 1000 mg/m(2) (Day 1); cisplatin 25 mg/m(2) or 30 mg/m(2) (Days 1-4); vinblastine 1.6 mg/m(2) or 1.8 mg/m(2) (Days 1-5); interleukin-2 9 million units (MU) per m(2) or 12 MU/m(2) as a 24-hour continuous infusion (Days 1-4); and interferon-alpha-2b 5 MU/m(2), 10 MU/m(2), or 15 MU/m(2) (Days 1-5) and 5 MU/m(2) (Days 7, 9, and 11) administered subcutaneously. RESULTS: Of the 19 patients who were enrolled, 18 were evaluable for toxicity and response. Sixty-nine treatment courses were administered in total (median, 4 courses per patient; range, 1-6 courses per patient), with reduction of the dose of at least 1 agent being required in 7 courses (10%). Twenty-six courses were delayed by a median of 7 days (range, 3-29 days), with interferon-alpha-2b administration frequently omitted because of thrombocytopenia, most often after Day 5. Blood product support was required in 40 courses. Dose-limiting toxic effects included global encephalopathy, renal and hepatic dysfunction, pancreatitis, and ileus. There was 1 complete response, and there were 10 partial responses. The median time to disease progression was 6.9 months, and the median survival duration was 12.2 months. CONCLUSIONS: Although dose intensification can be achieved safely in patients with advanced melanoma, other strategies should be pursued to enhance the clinical activity of biochemotherapy as a response induction regimen.

Phase II evaluation of paclitaxel by short intravenous infusion in metastatic melanoma.

In four clinical trials in mostly chemotherapy-naive patients with metastatic melanoma, paclitaxel was found to be effective with a response rate of 16%. In vitro studies have shown that following exposure of cancer cells to paclitaxel for 1 h, sensitivity to repeat paclitaxel doses decreased markedly at 48-72 h and returned at 120 h. In this phase II study we assessed the efficacy of paclitaxel at a dose of 90 mg/m per day given intravenously over 80 min on days 1, 5 and 9 every 3 weeks, initially in two groups of 14 patients with metastatic choroidal and non-choroidal melanoma. One patient in the non-choroidal melanoma group had a confirmed response, and 23 additional patients were therefore accrued to this group. (One patient withdrew consent for treatment within a week from start of therapy. The patient was considered to have received inadequate treatment and a replacement was registered.) A total of 52 patients with a median age of 55 years (range 21-79 years) were treated. Forty-four patients completed two or more courses of paclitaxel and were evaluable for response. We observed >50% tumour regression in six patients. All the responses except one were amongst the 32 evaluable patients with non-choroidal melanoma. The response rate in this group was 15.6%. During the 219 courses of paclitaxel delivered, the side effects were mild, manageable and mostly reversible. No grade 3 acute allergic reactions were observed. Paclitaxel given by short intravenous infusion is marginally active against previously treated non-choroidal melanoma.

Biochemotherapy in patients with metastatic anorectal mucosal melanoma.

BACKGROUND: Patients with metastatic anorectal melanoma generally have an unfavorable prognosis, but no effective systemic therapy has been reported. METHODS: The authors retrospectively evaluated the medical records of all patients with metastatic anorectal melanoma treated with biochemotherapy between January 1991 and December 2001 at the University of Texas M. D. Anderson Cancer Center (Houston, TX). RESULTS: The search yielded 18 patients. Of these patients, 14 had undergone treatment with cisplatin (CDDP), vinblastine (VB), dacarbazine (DTIC), interferon alpha-2b (IFN), and interleukin 2 (IL-2); 2 had undergone treatment with CDDP, VB, DTIC, and IFN; 1 had undergone treatment with CDDP, IFN, and IL-2; and 1 had undergone treatment with CDDP, VB, temozolomide, IFN, and IL-2. All IL-2 treatments were administered intravenously. The median follow-up time was 12.2 months (range, 3.5-43.7 months). Eight patients (44%) had major responses, including two (11%) complete responses (CRs). Three patients were lost to follow-up evaluation after the completion of treatment. The median time to progression among the 15 remaining patients was 6.2 months. Four patients, including 1 with a CR, were alive at their last documented follow-up visits (survival: 14.0, 20.7, 31.3, and 43.7 months, respectively). The median overall survival was 12.2 months. Among 13 patients who received biochemotherapy as first-line systemic therapy, 6 patients (46%) had major responses, including two (15%) CRs. The median time to progression for this group was 6.2 months, and the median overall survival was 12.9 months. CONCLUSIONS: Biochemotherapy had substantial activity against metastatic anorectal melanoma and should be considered for use in the treatment of metastatic disease from primary anorectal melanoma.

Imatinib mesylate inhibits platelet-derived growth factor receptor phosphorylation of melanoma cells but does not affect tumorigenicity in vivo.

Platelet-derived growth factor (PDGF) and its cognate receptor are widely expressed on melanomas. Coexpression of the growth factor and receptor suggests their role in autocrine or paracrine growth mechanisms. Imatinib mesylate was previously reported to have specific activity in inhibiting select tyrosine kinase receptors, including PDGF and c-Kit. Melanoma cells express abundant levels of the PDGF receptor (PDGFR). Nevertheless, c-Kit expression is progressively lost as the cells take on a more highly metastatic phenotype. To investigate the potential of imatinib mesylate as a therapy for melanoma, we studied its effect on the growth of melanoma cells using an in vivo mouse model. Melanoma cells with high malignant potential (PDGFR-positive, c-Kit-negative) or low malignant potential (PDGFR-positive, c-Kit-positive) were injected subcutaneously into athymic nude mice. Mice were treated with imatinib mesylate (100 mg/kg three times weekly) or with phosphate-buffered saline for 4 to 6 wk. PDGFR-alpha and -beta were expressed on all melanoma cell lines tested. The level of PDGFR expression correlated with the metastatic potential of the melanoma cells: higher levels of PDGFR-alpha were expressed on cells with higher metastatic potential, and higher levels of PDGFR-beta were expressed on cells with lower metastatic potential. There was no significant difference in tumor size between treated and control mice. Immunohistochemical studies demonstrated inhibition of PDGFR phosphorylation on the tumors from mice treated with imatinib mesylate but not from control mice, suggesting that the receptors were functional and that the concentration of drug used was appropriate. Our data demonstrated that imatinib mesylate blocked both PDGFR-alpha and PDGFR-beta in vivo. It did not, however, affect the growth of melanoma cells expressing PDGFR, regardless of whether the cells expressed c-Kit.