Combination therapy: intermittent sorafenib with bevacizumab yields activity and decreased toxicity.

BACKGROUND: We previously reported preliminary results of our phase I study of continuous daily sorafenib with bevacizumab every other week for solid tumours. Toxicity was moderate, leading to additional dose levels (DL) testing intermittent sorafenib dosing. METHODS: Seventeen patients with advanced solid tumours were treated on three additional DLs testing sorafenib days 1-5 per week. Dose level 4 was sorafenib 200 mg twice daily (b.i.d.) and bevacizumab 5 mg kg(-1). DL5 alternated between bevacizumab 10 mg kg(-1)-sorafenib 200 mg b.i.d. (A) and sorafenib 400 mg b.i.d. with bevacizumab 5 mg kg(-1) (B). Outcome and toxicity data from 19 epithelial ovarian cancer (EOC) patients from DL 1-5 were analysed. RESULTS: Fewer patients required sorafenib dose reduction with the intermittent schedule (41 vs 74% daily, P=0.01). Hand-foot skin reaction (HFSR) remained the primary cause of dose reduction (n=5). Partial responses (12%) or disease stabilisation > or =4 months (53%; median 6 (4-26)) occurred in most patients on the intermittent schedule. Partial response occurred in 47% EOC patients treated in pooled analysis of duration 4-37 months. CONCLUSION: Intermittent sorafenib dosing with bevacizumab has promising clinical activity and less sorafenib dose reduction and side effects, but does not ameliorate HFSR. We are conducting a phase II clinical trial with intermittent sorafenib and bevacizumab in patients with EOC.

A phase I trial of carboxyamido-triazole and paclitaxel for relapsed solid tumors: potential efficacy of the combination and demonstration of pharmacokinetic interaction.

PURPOSE: Preclinical and clinical investigation of the combination of the antiangiogenesis/anti-invasion agent carboxyamido-triazole (CAI) administered with the cytotoxic agent paclitaxel (PAX). EXPERIMENTAL DESIGN: Colony-forming assays were used to test the activity of CAI plus PAX on A2780 human ovarian cancer. The sequence of CAI followed by PAX (CAI>Pax) was modeled in nude mice to test for potential additive toxicity. The Phase I clinical dose escalation schema tested p.o. administered CAI in PEG-400 (50-100 mg/m(2)) or micronized CAI (250 mg/m(2)) for 8 days followed by a 3-h infusion of PAX (110-250 mg/m(2)) every 21 days. Patients were assessed for toxicity, pharmacokinetics of CAI and PAX, and disease outcome. RESULTS: In preclinical studies, CAI>Pax was additive in A2780 human ovarian cancer cell lines when CAI (1 or 5 microM) preceded subtherapeutic doses of PAX. CAI did not reverse PAX resistance and collateral resistance to CAI was documented in PAX-resistant cells. CAI>PAX administration had no overt additive toxicity in nude mice. Thirty-nine patients were treated on a dose-escalation Phase I trial using daily oral CAI for 8 days followed by the PAX infusion. Pharmacokinetic analysis revealed that PAX caused an acute increase in circulating CAI concentrations in a dose-dependent fashion. No additive or cumulative toxicity was observed, and grade 3 nonhematological toxicity was rare. Three partial responses and two minor responses were observed. CONCLUSIONS: The sequential combination of CAI and PAX is well tolerated, and the activity observed suggests that further study of the combination is warranted.

Dose intensive combination platinum and cyclophosphamide in the treatment of patients with advanced untreated epithelial ovarian cancer.

BACKGROUND: The authors combined cisplatin and carboplatin together with cyclophosphamide to maximize platinum dose intensity in patients with advanced epithelial ovarian cancer (AOC). METHODS: The authors treated 26 consecutive, newly diagnosed patients with International Federation of Gynecology and Obstetrics (FIGO) Stage III/IV AOC with carboplatin, 600 mg/m2, on Day 1; cyclophosphamide, 250 mg/m2, on Day 1; and cisplatin, 100 mg/m2, on Day 8 every 4 weeks with or without pretreatment with amifostine (range, 740-1140 mg/m2). Platinum dose intensity was estimated using a 4:1 conversion for equipotent doses of cisplatin and carboplatin for expression as cisplatin dose equivalents (CDE). RESULTS: The mean administered CDE was 49.4 mg/m2/week, which was 79% of the planned dose. Hematologic toxicity was severe, with FIGO Grade 3-4 anemia in 81% of patients, Grade 3-4 neutropenia in 92% of patients, and Grade 4 thrombocytopenia in 96% of patients. Eleven patients (42%) were admitted to the hospital for febrile neutropenia and there was 1 toxic death. Sensory neuropathy > or = Grade 2 occurred in 10 patients (38%), ototoxicity > or = Grade 2 occurred in 18 patients (69%), and 6 patients (23%) required long term hearing aids. Elevations in serum creatinine > or = Grade 2 occurred in 7 patients (27%) and > or = Grade 2 hypomagnesemia was noted in 23 patients (88%). Other Grade 3 toxicities were nausea (42%), emesis (38%), fatigue (15%), mucositis (4%), and respiratory toxicities (4%). Twenty-two of 26 patients (85%) had a clinical response (19 with a complete response [CR] and 3 with a partial response). Pathologic CR was demonstrated in 10 of 26 patients (38%) and residual microscopic disease in 4 of 26 patients (15%) for a total pathologic response rate of 53%. The median progression free survival was 13.5 months and the median overall survival was 37.2 months at a median potential follow-up of 79.3 months. Three of 26 patients remained free of disease at 66, 71, and 103 months, respectively. CONCLUSIONS: Although dose intensive combination platinum treatment combined with cyclophosphamide in patients with AOC is active, it also is associated with substantial toxicity.

Phase I trial of micronized formulation carboxyamidotriazole in patients with refractory solid tumors: pharmacokinetics, clinical outcome, and comparison of formulations.

PURPOSE: Cytostatic agents targeted against angiogenesis and tumor cell invasive potential form a new class of investigational drugs. Orally administered carboxyamidotriazole (CAI) (NSC609974) is both antiangiogenic and antimetastatic. An encapsulated micronized powder formulation has been developed to optimize CAI administration. A phase I dose escalation trial with pharmacokinetic analysis has been performed. PATIENTS AND METHODS: Twenty-one patients with refractory solid tumors and good end organ function and performance status were enrolled onto the study. Patients received a test dose followed 1 week later by daily administration of CAI in the encapsulated micronized formulation at doses of 100 to 350 mg/m2. Patients remained on CAI until disease progression or dose-limiting toxicity. Plasma samples were taken to characterize the pharmacokinetic parameters of this formulation of CAI. RESULTS: All patients were assessable for toxicity and 18 were assessable for pharmacokinetics and response analysis. Grade 1 and 2 gastrointestinal side effects were observed in up to 50% of patients. Dose-limiting toxicity was observed in both patients treated at 350 mg/m2/d, consisting of reversible grade 2 to 3 cerebellar ataxia (n = 1) and confusion (n = 1). One minor response (MR) was observed in a patient with renal cell carcinoma and another nine patients had disease stabilization (MR + SD = 47%). Pharmacokinetic analysis demonstrated reduced bioavailability (58% reduction) compared with the PEG-400 liquid formulation previously reported. CONCLUSION: The better toxicity profile of encapsulated micronized CAI with similar frequency of disease stabilization and ease of administration compared with the liquid or gelatin capsule, suggests that the micronized formulation is a preferable formulation for subsequent studies. A dose of 300 mg/m2/d is proposed for phase II investigations.

A phase I/II study of dose-intense paclitaxel with cisplatin and cyclophosphamide as initial therapy of poor-prognosis advanced-stage epithelial ovarian cancer.

Epithelial ovarian cancer patients with bulky residual tumor have a poor response to therapy and limited survival. We investigated the addition of dose-intense paclitaxel to cisplatin and cyclophosphamide for patients with FIGO III/IV epithelial ovarian cancer. Paclitaxel dose was intensified from 135 to 250 mg/m2 and administered in combination with cisplatin at > or = 75 mg/m2 and cyclophosphamide at 750 mg/m2. Thirty-one of 36 patients (86%) and 25 (70%) had > or = 2 and > or = 3 cm residual disease after surgery, respectively. One-third had stage IV disease, and 80% had grade 3 tumors. The maximally tolerated doses (MTD) were paclitaxel at 250 mg/m2, cisplatin at 75 mg/m2, and cyclophosphamide at 750 mg/m2 on a 21-day cycle with G-CSF, 10 micrograms/kg/day. Administered dose intensity at the MTD was > or = 86%. Reversible grade 3 peripheral neuropathy occurred in 28% of patients and fever during neutropenia in 2/352 cycles (0.5%). The pathologic response rate is 36% with an additional 25% having minimal microscopic disease. Median progression-free and overall survivals for patients receiving paclitaxel at 250 mg/m2 at a median potential follow-up of 22 months have not been reached for the cohort nor for the > or = 3-cm subgroup. This regimen should be evaluated in a prospective, randomized clinical trial.

Cutaneous manifestations of Taxol therapy.

Taxol is a novel chemotherapeutic agent that has produced substantial responses in early clinical studies [1]. Taxol has excellent activity in a number of malignancies based on recently completed clinical trials, including a 30% response rate in platinum-refractory ovarian cancer patients [2-5]. We are currently conducting trials of dose-intense taxol with granulocyte colony stimulating factor (G-CSF) support in relapsed or refractory ovarian cancer patients. Such dose intensification produces a major response rate in 50% of patients with this disease [6]. Taxol was supplied in 5 ml ampules (6 mg/ml) in polyethoxylated castor oil (Cremophor EL) 50% and dehydrated alcohol and the dose was diluted in either 0.9% sodium chloride or 5% dextrose at concentrations of 0.6 to 1.2 mg/ml. We have noted 3 patients with previously unreported cutaneous manifestations which we believe are taxol related and also report our overall complication rate with the administration of taxol by peripheral intravenous lines.

Flexible granulocyte colony-stimulating factor dosing in ovarian cancer patients who receive dose-intense taxol therapy.

As has been reported with other chemotherapeutic agents, evidence is emerging to suggest that increased taxol dose intensity is associated with improved therapeutic efficacy. Granulocyte colony-stimulating factor (G-CSF) effectively protects the bone marrow from taxol-induced neutropenia and allows for higher taxol dose administration. This report addresses the optimal use of G-CSF as a supportive agent for dose-intense taxol therapy. Forty-seven patients were evaluated. Each ovarian cancer patient received taxol with G-CSF support, with starting doses of 250 mg/m2 per 21 days and 10 micrograms/kg/d, respectively. Five patients were treated with the same dose of G-CSF for multiple cycles. Forty-two patients were given "flexible" G-CSF dosing. Instead of reducing taxol dose after a cycle of therapy complicated by febrile neutropenia (F+N+), the G-CSF dose was increased. Only after a second episode of F+N+ was the taxol dose reduced. The initial 5 patients who developed F+N+ after taxol (250 mg/m2) and G-CSF (10 micrograms/kg/d) were retreated at the same doses of both drugs; subsequently, 4 of 5 patients had another episode of F+N+. With flexible G-CSF dosing, taxol dose intensity could be maintained at the target level in 34 of 42 patients (81% of the cohort). Sixteen of these patients (38% of the cohort) would have required taxol dose reductions for F+N+ if flexible G-CSF dosing had not been used. By increasing the G-CSF dose when indicated, patients at high risk for recurrence of F+N+, because they had already experienced one episode, appeared to have a lower risk of developing a recurrent episode. These data suggest that flexible G-CSF dosing may have merit and may allow the administration of more dose-intense taxol. A prospective, randomized, controlled clinical trial of flexible G-CSF dosing versus fixed-dose G-CSF appears warranted.

Incapacitating autonomic neuropathy precipitated by taxol.

Taxol is one of the more significant advances in cancer chemotherapy in the last 10-15 years with a 30-50% response rate in both breast and ovarian cancers. The toxicity profile of taxol is still evolving as changes in the dosing and scheduling of the drug are instituted. We herein present the first evidence of taxol-induced quantifiable, objective autonomic neuropathy in two patients, one with and one without diabetes. The patients did not have symptoms of autonomic dysfunction prior to taxol therapy. Both developed severe orthostatic hypotension following completion of 24-hr infusional taxol at 170-250 mg/m2 and both improved markedly on fludrocortisone. Other possible etiologies of orthostatic hypotension were ruled out. Noninvasive autonomic tests performed on the first patient included tilt test, Valsalva ratio, heart rate variation with respiration, and change in diastolic blood pressure with hand grip; all were markedly abnormal. Noninvasive autonomic tests should be considered as part of the evaluation of patients on taxol who develop generalized weakness and orthostasis.

A phase I clinical and pharmacological study of weekly intravenous infusions of piritrexim (BW301U).

Thirty-eight patients with advanced resistant cancers were enrolled on this study of piritrexim (PTX; BW 301U) administered intravenously weekly for 4 weeks. Of 50 courses of treatment begun, 39 evaluable 4-week courses of the drug were completed by this group of patients. Dosages ranged from 44 to 530 mg/m2/week. One patient at each dosage level received an initial weekly dose of PTX in oral form accompanied by pharmacokinetic blood sampling after the oral dose and also after a subsequent intravenous dose. Toxicities included mild nausea and vomiting, and moderate to severe peripheral vein phlebitis. Anemia and thrombocytopenia were the dominant hematological toxicities. One patient with pulmonary metastases from malignant fibrous histiocytoma experienced a 12-week partial response to PTX treatment at a dosage of 400 mg/m2/week. Pharmacokinetic analysis of plasma for PTX concentrations was accomplished utilizing a competitive protein binding assay. The estimated total body clearance ranged from 136 to 173 ml/min/1.73 m2. Mean terminal half-life after intravenous administration was 5.61 +/- 2.38 h (S.D.), and after oral administration was 5.72 +/- 2.04 h. Mean systemic bioavailability after oral administration was 75 +/- 56%.

Phase I study of alpha 2-interferon plus doxorubicin in patients with solid tumors.

Cytotoxic chemotherapy and interferon have shown synergistic antitumor activity in vitro. The purpose of this study was to determine the maximally tolerated dose of doxorubicin given every 3 weeks, in patients receiving recombinant alpha 2-interferon [10 X 10(6) IU/m2 s.c. three times per week (Monday, Wednesday, and Friday)] during the first 2 weeks of each cycle of doxorubicin. Fourteen patients received a total of 41 cycles. Hematological toxicity was dose limiting with granulocytopenia (total granulocyte count, less than 1000) occurring in 50% of patients treated with doxorubicin at 40 mg/m2 and in 25% of patients treated with doxorubicin at 30 mg/m2. Nonhematological toxicities included a flu-like syndrome, alopecia, nausea, vomiting, diarrhea, and transient mild increases in liver function tests. A partial response was seen in one patient with metastatic squamous cell carcinoma of the skin and in another patient with metastatic adenocarcinoma of the pancreas. Concomitant administration of recombinant alpha 2-interferon given on this schedule limits the amount of doxorubicin that can be administered. However, the responses noted in this study are encouraging enough to warrant additional studies of doxorubicin plus recombinant alpha 2-interferon.