Enhanced delivery of boronophenylalanine for neutron capture therapy of brain tumors using the bradykinin analog Cereport (Receptor-Mediated Permeabilizer-7)

OBJECTIVE: Using the well-characterized F98 rat glioma model, the purpose of the present study was to determine whether the delivery of boronophenylalanine (BPA) could be enhanced by prior administration of the bradykinin analog Cereport (Alkermes, Inc., Cambridge, MA) (previously known as Receptor-Mediated Permeabilizer-7), which produces a transient, pharmacologically mediated opening of the blood-brain barrier. METHODS: Two series of experiments were performed in F98 glioma-bearing rats that had received either intracarotid (i.c.) or intravenous infusions of Cereport (at doses ranging from 1.5 to 7.5 microg/kg of body weight), followed by i.c. (or intravenous) injection of BPA (300 mg/kg of body weight). Animals were killed 0.5, 2.5, or 4 hours later, samples of blood, skin, muscle, and eye were obtained, brains were removed, and tumors were excised for boron determination by direct current plasma-atomic emission spectroscopy. RESULTS: Averaged over all time points, i.c. infusion of Cereport significantly enhanced tumor boron uptake (P = 0.0001), compared with the excipient (saline) control values. Tumor boron values were equivalent at 0.5 (36.0 microg/g) and 2.5 hours (38.5 microg/g) after i.c. administration of Cereport and BPA and then decreased by 33% (to 25.7 microg/g) at 4 hours. These tumor boron uptake values were significantly different (alpha = 0.05), compared with values measured at the corresponding times after i.c. administration of BPA without Cereport (22.6, 21.8, and 15.3 microg/g, respectively). Although no time-related effects were observed, i.c. administration of Cereport followed by intravenous administration of BPA also significantly enhanced (alpha = 0.05) tumor boron uptake at 0.5, 2.5, and 4 hours (27.4, 30.3, and 28.0 microg/g, respectively), compared with values obtained without Cereport (11.3, 13.4, and 15.2 microg/g, respectively). Boron levels in normal brain tissue from tumor-bearing and non-tumor-bearing cerebral hemispheres and in blood were not significantly different from those measured in saline-treated control animals. CONCLUSION: This study established that i.c. infusion of Cereport significantly increased delivery of BPA to F98 rat gliomas, and this could enhance the efficacy of boron neutron capture therapy of this tumor.     

Tyrosine kinase and c-Jun NH2-terminal kinase mediate hypertrophic responses to prostaglandin F2alpha in cultured neonatal rat ventricular myocytes

RMP-7 is a bradykinin B2 receptor agonist shown to permeabilize the blood-brain barrier, especially that associated with brain tumors, when administered via both intracarotid and intravenous routes. Both routes of administration are currently being tested in human trials in combination with the chemotherapeutic agent carboplatin as therapy for gliomas. As an essential prerequisite to the initial intracarotid clinical trials, the potential neurotoxicity of intra-arterial administration of RMP-7 (at a high or low dose), alone and in combination with carboplatin, was assessed in anesthetized Red Duroc swine. Five treatment groups were evaluated with each pig receiving a series of alternating, intra-arterial infusions of RMP-7 (or saline) followed by carboplatin (or saline), as follows: (1) vehicle control: saline/saline; (2) carboplatin only control: saline/carboplatin (50 mg total); (3) RMP-7 only control: RMP-7 (750 ng/kg)/saline; (4) low dose combination: RMP-7 (75 ng/kg)/carboplatin (50 mg total); and (5) high dose combination: RMP-7 (750 ng/kg)/carboplatin (50 mg total). For each subject, one of the alternating dosing sequences (above) was repeated four times during a single dosing session which lasted approximately 40 minutes. Assessments during the in-life phase of the study in the pre- and post-treatment periods consisted of heart rate, arterial blood pressure (systolic, diastolic, and mean), blood gases, body weight, general clinical observations (including evaluation for neurological deficit) and clinical pathology (including a comprehensive battery of standard blood coagulation, hematological and serum chemistry tests). In addition, during the time of treatment, heart rate and arterial blood pressure were monitored. The animals were terminated two weeks after dosing and the brain and rete mirabile (distal to site of infusion) were evaluated for gross and histopathological abnormalities. The histopathology analysis included a reader-blinded analysis using low and high power light microscopic examination of both H&E and Kluver-Berrera stained sections through several key cortical and subcortical brain regions. Transient decreases in arterial blood pressure (mean of 10-25 mmHg) were observed in both groups receiving the high dose of RMP-7 (i.e., 750 ng/kg). No other side effects attributable to RMP-7 and/or carboplatin were observed, and clinical observations revealed no evidence of neurologic deficits. Post-mortem examination revealed no evidence of CNS or cerebral vascular pathology attributable to carboplatin and RMP-7. This study demonstrates that intracarotid administration of the maximum tolerated dose of RMP-7 (750 ng/kg) alone, or in combination with carboplatin (50 mg) is not accompanied by any serious adverse effect, apparent cerebrovascular abnormality or neuropathologic consequence and offers further evidence for the safety of this novel therapeutic approach for enhancing delivery of chemotherapeutics to brain tumors.     

Advances in antiviral therapy

The maximum tolerated dose (MTD) of etoposide and carboplatin without growth factor support was previously defined by Cancer and Leukemia Group B (CALGB) as 200 and 125 mg/m2/day x 3, respectively, given every 28 days to previously untreated patients who have extensive, small-cell lung cancer (SCLC). Myelosuppression was dose-limiting. The purpose of this phase I trial was to determine if granulocyte macrophage colony-stimulating factor (GM-CSF) support allows the dosage of the combination of etoposide and carboplatin to be increased above the previously determined MTD. In this CALGB study of 44 evaluable patients with performance status 0-2, cohorts were treated with etoposide and carboplatin given intravenously on days 1-3 followed by GM-CSF (molgramostim) given subcutaneously on days 4-18. Four dose levels of bacteria-derived recombinant GM-CSF (5, 10, 20 microg/kg/day and 5 microg/kg every 12 h), three dose levels of etoposide (200, 250, and 300 mg/m2/day x 3), and two dose levels of carboplatin (125 and 150 mg/m2/day x 3) were evaluated. There was no chemotherapy dose escalation in individual patients. With 5 microg/kg/d GM-CSF, the first etoposide and carboplatin cycle of 300 and 150 mg/m2/day x 3, respectively, could be administered with acceptable toxicity. However, GM-CSF did not allow repeated administration of this dose-escalated regimen every 21 days, since delayed platelet and/or neutrophil recovery was dose limiting in later cycles. These results demonstrate that GM-CSF alone has limited capability to support the repeated administration of high doses of etoposide and carboplatin. CALGB currently is testing the ability of interleukin (IL)-6 given with GM-CSF to ameliorate the cumulative myelosuppression of this intense regimen.     

Interleukin-1alpha synergistic in vivo enhancement of cyclophosphamide- and carboplatin-mediated antitumor activity

Interleukin-1alpha (IL-1alpha) has potent acute antitumor activity in vivo and can enhance the efficacy of chemotherapeutic drug-mediated antitumor responses. Studies were undertaken to examine the ability of IL-1alpha to enhance the activity of cyclophosphamide (CTX) administered in combination with carboplatin. To determine the in vivo effect of IL-1alpha, CTX and/or carboplatin, mice bearing 14-day RIF-1 tumors were treated on day 0 with a concurrent i.p. injection of varying doses of CTX (5-150 mg/kg), human IL-1alpha (125 microg/kg), and carboplatin (50 mg/kg) and examined 24 h later for the surviving fraction by the in vivo excision clonogenic-tumor-cell assay. Even at the lowest doses of CTX, IL-1alpha significantly enhanced the clonogenic tumor cell kill when compared to treatment with CTX alone. When carboplatin was added to the treatment schema, significantly greater clonogenic cell killing and tumor regrowth delay were observed as compared to any agent alone or a two-drug combination (CTX/IL-1alpha or CTX/carboplatin). Significant enhancement was observed even at low doses of CTX in combination with carboplatin and IL-1alpha. The interaction between the three-drug combination was found to be synergistic as determined by the median dose effect with significant dose reduction apparent for IL-1alpha and CTX when used in this combination. These results demonstrate that IL-1alpha can synergistically enhance the antitumor efficacy of CTX and the combination of CTX and carboplatin.     

Multiple resistance modulators combined with carboplatin for resistant malignancies: a pilot study

BACKGROUND: Chemotherapy resistance is probably multifactorial; hence, we assessed the feasibility of adding to carboplatin 6 concurrent resistance modulators in 53 patients with resistant cancers. METHODS: Pentoxifylline and dipyridamole were added to carboplatin 400 mg/m2 in cohort 1, and metronidazole was also given in cohort 2. Mannitol and saline were administered in each cohort with the theoretical objective of improving carboplatin delivery to tumors by reducing blood viscosity. Because of excessive toxicity in cohort 2, cohort 3 received the same modulators as in cohort 2 but with a reduced dose of carboplatin (200 mg/m2). Subsequent patients had the following drugs added to those in the previous cohort: novobiocin (cohort 4), tamoxifen (cohort 5), ketoconazole (cohort 6). Cohort 7 patients received the 6 cohort 6 modulators along with carboplatin 300 mg/m2. RESULTS: Thrombocytopenia was excessive in early cohorts with a carboplatin dose of 400 mg/m2, but was minimal at lower doses. Other toxicity was generally tolerable and reversible, particularly at carboplatin doses < or = 300 mg/m2, although gastrointestinal and neurological toxicity tended to worsen as additional modulators were added. No major responses (but 4 minor responses) were seen in this patient population with heavily pretreated or primarily resistant cancers. CONCLUSIONS: Acceptable doses for phase II studies are carboplatin 300 mg/m2, 20% mannitol 250 ml plus normal saline 500 ml over 1 hr prior to carboplatin, pentoxifylline 700 mg/m2/day p.o. from 3 days before carboplatin to cessation of therapy, dipyridamole 100 mg/m2 p.o. q6h x 6 days starting 24 hr before carboplatin, metronidazole (750 mg/m2 p.o. 12 hr and immediately before, and 24 hr after carboplatin; 250 mg/m2 suppository p.r. 12 hr and immediately before, and 6 and 24 hr after carboplatin; and 500 mg/m2 i.v. right after carboplatin), novobiocin 600 mg/m2 p.o. q12h x 6 days starting 24 hr before carboplatin, and tamoxifen 100 mg/m2/day plus ketoconazole 700 mg/m2/day x 3 days starting the day before carboplatin, with oral dexamethasone and ondansetron as antimetics.     

Phase I trial of intravenous carboplatin and cyclosporin A in refractory gynecologic cancer patients

Our objective was to determine the maximum tolerated dose of cyclosporin A (CsA) delivered as a loading dose (LD) and continuous i.v. infusion (CI) in combination with carboplatin in patients with refractory gynecologic cancers. Twenty-nine heavily pretreated patients (25 ovarian epithelial, 2 cervical, and 2 endometrial carcinomas) received 113 cycles of CsA and carboplatin from September 1989 to September 1991. Twenty-four of these 29 carcinomas were strictly defined to be platinum resistant. CsA was administered as a LD escalated from 6 to 10 mg/kg followed by a 24-h CI from 2.5 to 14.5 mg/kg/day. Carboplatin was targeted to an area under the time versus concentration curve (AUC) of 6 mg/ml x min and was not dose escalated. Whole-blood CsA concentrations (fluorescence polarization immunoassay) at the maximum tolerated dose (10 mg/kg LD, 14.5 mg/kg/day CI) ranged from 2.4 to 3.0 microgram/ml over 12 h. Estimated median carboplatin AUC, based on calculated carboplatin clearance, was 7.9 mg/ml x min. The dose-limiting toxicity of the combination of CsA and carboplatin was grade 4 thrombocytopenia. Grade 3 or 4 thrombocytopenia occurred in 35% of the patients, which could be explained by the effects of carboplatin (AUC of 6 mg/ml x min) alone. Overall, neutropenia occurred in 24% of the patients and anemia in 17% of the patients. Grade 3 or 4 nausea or vomiting was noted in 10 and 14% of the patients, respectively. Grade 3 hypertension during CsA administration occurred in 14% of the patients. No grade 3 or 4 nephrotoxicity was seen in this trial. Three objective responses were noted: one complete response (11 months) and one partial response (5 months), both in potentially platinum-sensitive patients with platinum-free intervals of only 9 months each. One platinum-resistant patient had a partial response for 21 months. Five additional patients experienced >75% reduction of CA-125 or a return to a normal CA-125 titer. We concluded that whole-blood CsA concentrations of >3.0 microgram/ml (as seen when CsA is used as a modulator of multidrug resistance) were not achievable in this combination with carboplatin in this population of heavily pretreated gynecologic cancer patients. However, because CsA is used in this trial as a chemosensitizer in platinum-sensitive tumors and as a chemomodulator of platinum resistance, we targeted a CsA concentration of >1.0 microgram/ml, which was achieved. The CsA dose recommended for a Phase II trial of this combination is 10 mg/kg LD and 11.6 mg/kg/day CI, which results in blood CsA concentrations ranging from 1.2 to 1.3 microgram/ml over 12 h. Responses in this population of refractory gynecologic cancer patients are unusual, and these encouraging results form the basis for a Phase II trial of this combination.     

A multicenter randomized Phase II trial of granulocyte-colony stimulating factor-supported, platinum-based chemotherapy with flexible midcycle cisplatin administration in patients with advanced ovarian carcinoma. PSAMOMA Cooperative Group, Spain

BACKGROUND: The purpose of this study was to analyze whether the addition of granulocyte-colony stimulating factor (G-CSF) to platinum-based combination chemotherapy could increase platinum dose intensity and response rates and decrease hematologic toxicity in patients with advanced epithelial ovarian carcinoma. METHODS: Patients with untreated advanced ovarian carcinoma (International Federation of Gynecology and Obstetrics [FIGO] Stage IIC-IV) were treated after maximum debulking surgery with cyclophosphamide, 750 mg/m2, and carboplatin, 350 mg/m2, on Day 1 plus cisplatin, 75 mg/m2, on Day 14 when clinically indicated (adequate bone marrow and renal function). Patients were randomized to receive chemotherapy alone (Arm A) or chemotherapy supported with G-CSF (5 microg/kg subcutaneously on Days 2-13; Arm B). RESULTS: Between November 1993 and April 1995, 80 patients were included. Seventy-eight patients were evaluable for dose intensity calculations. Both groups were well matched with regard to age, Eastern Cooperative Oncology Group performance status, histopathologic subtype, tumor grade, FIGO stage, and residual tumor after surgery. The dose intensities calculated in mg/m2/week for cyclophosphamide and carboplatin were similar in both groups; however, the dose intensity of cisplatin was higher in Arm B (5.7 mg/m2 vs. 10.3 mg/m2). The occurrence of Common Toxicity Criteria Grade 3-4 neutropenia was less common in the G-CSF arm (55% vs. 7.7%). Response rates (52% vs. 68%) and pathologic complete responses (32% vs. 25%) were similar in both groups. CONCLUSIONS; The addition of G-CSF to this platinum-based chemotherapy regimen in patients with advanced ovarian carcinoma resulted in a modest increment in platinum dose intensity and appeared to reduce the incidence of Grade 3-4 neutropenia.     

Phase I and pharmacologic study of the combination paclitaxel and carboplatin as first-line chemotherapy in stage III and IV ovarian cancer

PURPOSE: To determine the maximum-tolerated dose for the combination paclitaxel and carboplatin administered every 4 weeks and to gain more insight into the pharmacokinetics and pharmacodynamics of this combination in previously untreated ovarian cancer patients. PATIENTS AND METHODS: Thirty-five chemotherapy-naive patients with suboptimally debulked stage III (tumor masses > 3 cm) and stage IV ovarian cancer were entered onto this phase I trial in which paclitaxel was administered as a 3-hour intravenous (IV) infusion at dosages of 125 to 225 mg/m2 immediately followed by carboplatin over 30 minutes at dosages of 300 to 600 mg/m2. A total of six courses was planned, followed by a second-look laparoscopy/laparotomy. Patients with a response and/or minimal residual disease at second-look laparoscopy received three additional courses. Twenty-six patients participated in the pharmacokinetic part of the study. RESULTS: The most important hematologic toxicity encountered was neutropenia. Neutropenia was more pronounced for the higher dose levels (DLs) and was cumulative. Thrombocytopenia was mild in the first eight DLs, but increased during the treatment courses. Nonhematologic toxicities consisted mainly of vomiting, neuropathy, fatigue, rash, pruritus, myalgia, and arthralgia. Dose-limiting toxicities (DLTs) in this trial were neutropenic fever, thrombocytopenia that required platelet transfusions, and cumulative neuropathy. Of 33 patients assessable for response, 26 major responders (78%, 20 complete response [CR] and six partial response [PR]) were documented. The maximal concentration (Cmax) of paclitaxel and the area under the concentration-time curve (AUC) were not different from the historical data for paclitaxel as a single agent. Retrospective analysis using a modified Calvert formula showed that the measured carboplatin AUCs in plasma ultrafiltrate (pUF) were 30% +/- 3.4% less than the calculated carboplatin AUC. Neutropenia was more pronounced than could be expected on the basis of the historical times above a threshold concentration greater than 0.1 mumol/L (T > or = 0.1 mumol/L) or 0.05 mumol/L (T > or = 0.05 mumol/L), and thrombocytopenia was less than could be expected from historical sigmoidal Emax models. CONCLUSION: The combination of paclitaxel 200 mg/ m2 and carboplatin 550 mg/m2 every 4 weeks is a well-tolerated treatment modality. The paclitaxel-carboplatin combination is highly active in stage III (bulky) and stage IV ovarian cancer. No indications for a pharmacokinetic drug-drug interaction between carboplatin and paclitaxel were found.     

Phase II trial of paclitaxel and carboplatin in the treatment of advanced urothelial carcinoma

PURPOSE: Both paclitaxel and carboplatin have single-agent activity against carcinoma of the urothelium. We evaluated the combination of paclitaxel and carboplatin in the treatment of advanced cancers of the urothelium. PATIENTS AND METHODS: Patients with cancers of the urothelium who had no prior chemotherapy (prior adjuvant chemotherapy > 6 months allowed) were eligible for treatment. Eligibility requirements were performance status of 2 or less, creatinine level less than 2.0 mg/dL, granulocyte count (AGC) 1,500/microL or greater, platelet count 100,000/microL or greater, and total bilirubin level less than 1.5 mg/dL. Paclitaxel 200 mg/m2 followed by carboplatin (area under the curve [AUC] 5, Calvert formula) were administered every 21 days. Patients were evaluated for toxicity weekly and assessed for response every 6 weeks. RESULTS: Thirty-six patients were entered onto the study and 35 patients were assessable for response. A total of 184 cycles were administered (median, six cycles per patient). Nine patients required one dose reduction, and seven patients required two dose reductions for a nadir AGC less than 500/microL, with only one episode of febrile neutropenia and sepsis. Myalgias and arthralgias of grades 1 to 2 occurred in 16 patients and usually lasted 2 to 3 days after treatment. There were no treatment delays because of toxicity. There were 18 responses; seven complete responses (CRs) and 11 partial responses (PRs) (response rate 51.5%; 95% confidence interval, 35 to 68). Median response durations for CR and PR were 6 and 4 months, respectively. Overall median survival was 9.5 months. CONCLUSION: The combination of paclitaxel and carboplatin is an active and well-tolerated regimen for the treatment of advanced urothelial carcinoma. Because of the modest toxicity of this combination, paclitaxel and carboplatin should be considered for addition to other agents with activity in urothelial carcinomas.     

Iodine-131-anti-B1 radioimmunotherapy for B-cell lymphoma

PURPOSE: The CD20 B-lymphocyte surface antigen expressed by B-cell lymphomas is an attractive target for radioimmunotherapy, treatment using radiolabeled antibodies. We conducted a phase I dose-escalation trial to assess the toxicity, tumor targeting, and efficacy of nonmyeloablative doses of an anti-CD20 monoclonal antibody (anti-B1) labeled with iodine-131 (131I) in 34 patients with B-cell lymphoma who had failed chemotherapy. PATIENTS AND METHODS: Patients were first given tracelabeled doses of 131I-labeled anti-B1 (15 to 20 mg, 5 mCi) to assess radiolabeled antibody biodistribution, and then a radioimmunotherapeutic dose (15 to 20 mg) labeled with a quantity of 131I that would deliver a specified centigray dose of whole-body radiation predicted by the tracer dose. Whole-body radiation doses were escalated from 25 to 85 cGy in sequential groups of patients in 10-cGy increments. To evaluate if radiolabeled antibody biodistribution could be optimized, initial patients were given one or two additional tracer doses on successive weeks, each dose preceded by an infusion of 135 mg of unlabeled anti-B1 one week and 685 mg the next. The unlabeled antibody dose resulting in the most optimal tracer biodistribution was also given before the radioimmunotherapeutic dose. Later patients were given a single tracer dose and radioimmunotherapeutic dose preceded by infusion of 685 mg of unlabeled anti-B1. RESULTS: Treatment was well tolerated. Hematologic toxicity was dose-limiting, and 75 cGy was established as the maximally tolerated whole-body radiation dose. Twenty-eight patients received radioimmunotherapeutic doses of 34 to 161 mCi, resulting in complete remission in 14 patients and a partial response in eight. All 13 patients with low-grade lymphoma responded, and 10 achieved a complete remission. Six of eight patients with transformed lymphoma responded. Thirteen of 19 patients whose disease was resistant to their last course of chemotherapy and all patients with chemotherapy-sensitive disease responded. The median duration of complete remission exceeds 16.5 months. Six patients remain in complete remission 16 to 31 months after treatment. CONCLUSION: Nonmyeloablative radioimmunotherapy with 131I-anti-B1 is associated with a high rate of durable remissions in patients with B-cell lymphoma refractory to chemotherapy.     

A phase II study of carboplatin, cisplatin, interferon-alpha, and tamoxifen for patients with metastatic melanoma

The purpose of this trial was to determine the toxicity and antineoplastic activity of cisplatin, carboplatin, tamoxifen, and interferon-alpha (IFN-alpha) in patients with advanced melanoma. Eleven patients with metastatic melanoma were enrolled. The patients received carboplatin 400 mg/m2 i.v. on day 0; cisplatin 25 mg/m2 i.v. on days 7, 14, and 21; tamoxifen 20 mg p.o. b.i.d. on days 0-27; and interferon-alpha 5 million units/m2 subcutaneously 3 times per week. Cycles were repeated every 28 days. Patients were assessed for tumor response at the end of 2 cycles. Toxicity was severe, with 14 of 24 cycles given requiring some form of dose reduction. Carboplatin dose reductions were related to bone-marrow toxicity, whereas IFN-alpha caused fatigue, arthralgias, myalgias, and fever. The overall response rate was 18% (2 partial responses [PRs]). The combination of cisplatin, carboplatin, tamoxifen, and IFN-alpha is active in advanced melanoma; however, the toxicity is unacceptable.     

Two cases of relapse or refractory germ cell tumor who had been treated with combination chemotherapy of cisplatin and carboplatin

We tried a combination chemotherapy with cisplatin (CDDP) and carboplatin (CBDCA) (CDDP/CBDCA regimen) as salvage therapy for 2 cases with recurrent or refractory Germ Cell Tumor (GCT). Case 1 was a 29-year-old man with 2nd relapsed embryonal carcinoma and seminoma originating from testis. Case 2 was a 23-year-old man with primary refractory embryonal carcinoma and yolk sac tumor originating from mediastinum. CDDP and CBDCA were administered at the dose of 120 mg/m2 and 350 mg/m2 on day 1, and vinblastin was administered at the dose of 10 mg/body on day 2. In one of two cases, a complete response was obtained. Non-hematologic toxicity of CDDP/CBDCA regimen was tolerable. It is suggested that this combination chemotherapy is useful for GCT recurrence.     

A phase II trial of 5-fluorouracil, leucovorin, and carboplatin in patients with unresectable biliary tree carcinoma

BACKGROUND: Unresectable adenocarcinoma of the biliary tree are associated with a very poor prognosis. 5-fluorouracil (5-FU) combination regimens have produced objective response rates in approximately 10-20% of patients. Leucovorin increases the selective cytotoxicity of 5-FU. There also are encouraging reports of carboplatin in combination with 5-FU in other gastrointestinal tract malignancies. METHODS: Fourteen consecutive eligible patients were treated with a combination of carboplatin, 300 mg/m2, intravenously (i.v.) on Day 1 only and 5-FU, 400 mg/m2, i.v. with leucovorin, 25 mg/m2, i.v. on Days 1-4. All patients were required to have a histologically confirmed diagnosis and measurable disease. Patients were evaluated for response, survival, and toxicity. RESULTS: A total of 48 cycles of therapy were delivered. The median survival was 5 months. One patient achieved complete remission and two others partial remission, for a total response rate of 21.4%. Four additional patients had stable disease for a median duration of 4 months. The therapy was well tolerated, with moderate myelosuppression as the main dose-limiting toxicity. CONCLUSIONS: The current combination regimen of leucovorin-modulated 5-FU with carboplatin is well tolerated with appropriate supportive care, produces significant objective responses in 21% of patients with biliary tree carcinoma, and should be considered for the treatment of this disease.     

Carcinoma of unknown primary site: treatment with 1-hour paclitaxel, carboplatin, and extended-schedule etoposide

PURPOSE: To evaluate the efficacy and toxicity of a novel chemotherapy combination that includes paclitaxel, carboplatin, and extended-schedule etoposide in the treatment of patients with carcinoma of unknown primary tumor site. PATIENTS AND METHODS: Fifty-five patients with carcinoma of unknown primary tumor site were treated with the following regimen, administered every 21 days: paclitaxel 200 mg/m2 by 1-hour intravenous (I.V.) infusion on day 1, carboplatin at an estimated area under the concentration-time curve (AUC) of 6.0 on day 1, and etoposide 50 mg alternated with 100 mg orally on days 1 through 10. Responding patients received a total of four courses of treatment. The following histologies were included: adenocarcinoma, 30 patients; poorly differentiated carcinoma (PDC) or poorly differentiated adenocarcinoma (PDA), 21; poorly differentiated neuroendocrine carcinoma, three; and squamous carcinoma, one. RESULTS: Twenty-five of 53 assessable patients (47%; 95% confidence interval [CI], 33% to 61%) had major objective responses to treatment (seven complete responses). Response rates were similar in patients with adenocarcinoma versus PDC (45% and 48%, respectively). The actuarial median survival time for the entire group was 13.4 months. The regimen was well tolerated, with only seven hospitalizations for treatment of neutropenia and fever (4% of courses) and no treatment-related deaths. CONCLUSION: The combination of paclitaxel, carboplatin, and extended-schedule etoposide is highly active and well tolerated in patients with carcinoma of unknown primary tumor site. Response rates and survival in this multicenter community-based trial compare favorably with all previously studied empiric regimens. In addition, this regimen is substantially less toxic and easier to administer than the cisplatin-based regimens previously used in this setting. If this level of efficacy is confirmed, this treatment should be considered standard first-line therapy in patients with carcinoma of unknown primary tumor site.     

Paclitaxel, carboplatin, and extended-schedule etoposide in the treatment of small-cell lung cancer: comparison of sequential phase II trials using different dose-intensities

PURPOSE: In two sequential phase II studies, we evaluate the feasibility and efficacy of adding paclitaxel to a standard platinum/etoposide regimen in the first-line treatment of small-cell lung cancer. PATIENTS AND METHODS: One hundred seventeen patients with small-cell lung cancer were treated between June 1993 and July 1996. The first 38 patients received a lower-dose regimen: paclitaxel 135 mg/m2 by 1-hour infusion, carboplatin at an area under the concentration-time curve (AUC) of 5.0, and etoposide 50 mg alternating with 100 mg orally on days 1 to 10. When only mild myelosuppression was observed, doses of paclitaxel and carboplatin were increased in the subsequent 79 patients (paclitaxel 200 mg/m2 by 1-hour infusion and carboplatin at an AUC of 6.0). All patients received four courses of treatment, administered at 21-day intervals. Patients with limited-stage small-cell lung cancer also received thoracic radiation therapy (1.8 Gy/d; total dose, 45 Gy) administered concurrently with courses 3 and 4 of chemotherapy. RESULTS: Seventy-two of 79 patients (91%) who receive the higher-dose regimen had major responses. Thirty-two of 38 (84%) with extensive-stage disease responded (21% complete response rate); median survival was 10 months for this group. With limited-stage disease, the overall response rate was 98%, with 71% complete responses; the median survival time has not been reached at 16 months. Median survival in extensive-stage patients was longer in patients who received the higher-dose regimen (10 months) than in the previous group treated with lower doses (7 months; P = .008). The higher-dose regimen was well tolerated, with myelosuppression being the major toxicity. Compared with the lower-dose regimen, grade 3/4 neutropenia increased from 8% to 38% of courses, but the incidence of hospitalization for neutropenia and fever did not increase. Other nonhematologic toxicities were uncommon, and did not increase substantially with the higher-dose regimen. CONCLUSION: Paclitaxel can be added at full dose (200 mg/m2) to a carboplatin/etoposide combination while maintaining a tolerable toxicity profile. Median survival times in both extensive- and limited-stage patients compare favorably with other reported regimens. This regimen merits further investigation, and a randomized trial to compare this regimen with a standard carboplatin/etoposide combination is underway.     

Phase II study of carboplatin as a single drug for relapsed Wilms' tumor: experience of the Brazilian Wilms' Tumor Study Group

A total of 15 patients with relapsed Wilms' tumor were treated with carboplatin as a single agent. There were six females and nine males, aged between 2 and 9 years (median:5). The treatment consisted of carboplatin given I.V. as a single agent at a dose of 550 mg/m2 over 1 hour every 3 weeks. There were four (26%) complete responses, four (26%) partial responses, one stable disease, and six with progressive disease. In all patients a total of 56 courses were given and the toxicities found were leukopenia and thrombocytopenia. The overall response rate was encouraging and the toxicity was acceptable and reversible.     

Interstitial delivery of carboplatin via biodegradable polymers is effective against experimental glioma in the rat

PURPOSE: Carboplatin has shown promise experimentally as an antineoplastic agent against both primary central nervous system (CNS) tumors and several solid tumors that frequently metastasize to the brain. Unfortunately, carboplatin is limited in its clinical use for tumors in the CNS by systemic toxicity and poor penetration through the blood brain barrier. Recent advances in polymer technology have made feasible the intracranial implantation of a biodegradable polymer capable of local sustained delivery of chemotherapy for brain neoplasms. This study assessed the toxicity and efficacy of carboplatin delivered from intracranial sustained release polymers in the treatment of experimental gliomas in rodents. METHODS: Two biodegradable anhydride polymer systems were tested: a copolymer of 1,3-bis-(p-carboxyphenoxy propane) and sebacic acid, and a copolymer of fatty acid dimer and sebacic acid. The polymers were loaded with carboplatin and dose escalation studies evaluating toxicity were performed by implanting carboplatin-loaded polymers into the brains of rats. Next, efficacy was tested. F-98 glioma cells were injected intracranially into rats, and 5 days later polymers containing the highest tolerated doses were implanted at the site of tumor growth. The survival of animals receiving carboplatin-loaded polymer was compared with that of animals receiving intraperitoneal doses of the same agent. RESULTS: Carboplatin-polymer was well tolerated at doses up to 5% loading in both polymer systems. Locally delivered carboplatin effectively prolonged survival of rats with F98 gliomas. Maximal treatment effect was seen with 5% loading of either polymer, with median survival increased threefold over control (P < 0.004). Systemic carboplatin also significantly prolonged survival, but the best intracranial polymer dose was significantly more effective than the best systemic dose tested. CONCLUSIONS: Carboplatin can be safely delivered intracranially by biodegradable sustained- release polymers. This treatment improves survival in rodents with experimental gliomas, with locally delivered carboplatin being more effective than systemic carboplatin.     

Evaluation of carboplatin pharmacokinetics in the absence and presence of paclitaxel

In a clinical trial of paclitaxel (Taxol) and carboplatin in combination, the severity of thrombocytopenia was less than would be expected with an equivalent dose of carboplatin alone. To determine whether a pharmacokinetic interaction was responsible for this observation, the effect of pretreatment with Taxol on the pharmacokinetics of carboplatin was examined in 11 patients. Each patient was randomized to one of two treatment groups that determined the order of drug treatments. The treatments were carboplatin as a 30-min infusion alone or immediately following 175 mg/m2 Taxol administered as a 3-h i.v. infusion. The treatments were separated by 1 week. The carboplatin dose was chosen to produce a target area under the concentration-time curve (AUC) of 3.75 mg-min/ml according to a previously published formula (A. H. Calvert et al., J. Clin Oncol., 7: 1748-1756, 1989). The mean administered dose of carboplatin was 338 mg. Serial blood samples were collected over 24 h and analyzed for total and free platinum, and, in some patients, Taxol. The pharmacokinetics of carboplatin (i.e., total clearance and volume of distribution at steady state), was not significantly affected by pretreatment with Taxol. Total clearances of carboplatin were 67.2 +/- 28.8 ml/min and 64.6 +/- 27.9 ml/min in the absence and presence of Taxol, respectively (P = 0.56). The AUC of free carboplatin (3.45 mg-min/ml) obtained in the absence of Taxol was not significantly different from that measured in the presence of Taxol (3.27 mg-min/ml). The AUC of carboplatin in both the absence and presence of Taxol agreed with the projected target AUC of 3.75 mg-min/ml. In conclusion, the application of an individualized dosing strategy is valid for the calculation of the carboplatin dose in this combination. The pharmacokinetics of carboplatin is not altered by pretreatment with Taxol at a standard dose, and a pharmacokinetic interaction is not responsible for the altered toxicity of the combination.     

Photodynamic therapy using mono-L-aspartyl chlorin e6 (Npe6) for the treatment of cutaneous disease: a Phase I clinical study

The activity of a new photosensitizer, mono-L-aspartyl chlorin e6 (Npe6), was assessed in an ascending dose Phase I study for patients with superficial tumor. Eleven patients, with a total of 14 tumor sites, were treated with photodynamic therapy (PDT) using Npe6. Lesions included recurrent adenocarcinoma of the breast, basal cell carcinoma, and squamous cell carcinoma. The phototherapy protocol consisted of a single i.v. injection of 0.5-3.5 mg/kg Npe6, followed 4 h later by 25-100 j/cm2 at 664 nm of light. PDT using Npe6 caused no significant toxicity with the exception of temporary generalized skin photosensitivity. In all cases, light treatment caused immediate tissue blanching, followed by a marked necrosis of the tumor mass. Regression of tumor occurred over 24-48 h after the light treatment and was followed by the formation of a heavy eschar over the tumor site. Tumor regression was short-lived at Npe6 doses of 1.65 mg/kg and below. In two of three patients, tumor regression was either incomplete or tumors recurred within the 12-week observation period. Increasing the Npe6 dose to 2.5 or 3.5 mg/kg combined with 100 J/cm2 of light energy resulted in better control of tumor regrowth with 66% (6/9) of sites remaining tumor-free through 12 weeks observation. This increased tumor response came at the expense of the tissue selectivity observed at Npe6 doses of 1.65 mg/kg and below. There was no apparent selectivity for destruction of tumor compared with normal skin at Npe6 doses of 2.5 mg/kg and above. These data demonstrate that Npe6 is both an effective and safe photosensitizer for use in PDT and provide the impetus for continued study in Phase II clinical trials.     

Primary targets for photoinactivation of vesicular stomatitis virus by AIPcS4 or Pc4 and red light

BACKGROUND: In a previous clinical trial, the authors disclosed that the expression of tumor cell motility factor gp78hAMFR correlates with tumor progression in patients with bladder carcinoma. This study was initiated to evaluate whether the combination of cytostatic drugs with an antimotility factor has an effect on chemotherapy-resistant bladder carcinoma. METHODS: In a Phase II trial, the authors evaluated the influence of paclitaxel, carboplatin, and an antimotility factor (acellular pertussis vaccine [APV]) in 18 patients with cisplatin- and methotrexate-resistant metastatic bladder carcinoma. Intramuscular injection of APV 3 times in the first week, on Days 1, 4, and 7, was followed by paclitaxel 135 mg/m2 and carboplatin 400 mg/m2. After an interval of 1 week APV was given again on Days 15 and 19. Each cycle lasted 3 weeks. On Day 22 the cycle was repeated. RESULTS: Four of 18 patients had objective responses (2 had complete remissions and 2 had partial remissions). After a median number of 2.5 cycles, side effects did not exceed World Health Organization Grade 4. CONCLUSIONS: The results of this clinical Phase II study demonstrate that the combination of paclitaxel-based therapy causes complete remissions previously not obtained with second-line chemotherapy, although no conclusions can be drawn as to the effectiveness of the individual substances. Further trials have to be evaluated with regard to the individual components.