A phase IB trial of the oral MEK inhibitor trametinib (GSK1120212) in combination with everolimus in patients with advanced solid tumors.

BACKGROUND: This phase Ib trial investigated the safety, tolerability, and recommended phase II dose and schedule of the MEK inhibitor trametinib in combination with the mammalian target of rapamycin (mTOR) inhibitor everolimus. Secondary objectives included pharmacokinetic (PK) characterization and evaluation of clinical activity. PATIENTS AND METHODS: A total of 67 patients with advanced solid tumors were enrolled in this open-label, single-arm, dose-escalation study. Dose escalation followed a 3 + 3 design. Patients were assigned to one of 10 different cohorts, involving either daily dosing with both agents or daily dosing with trametinib and intermittent everolimus dosing. This included an expansion cohort comprising patients with pancreatic tumors. PKs samples were collected predose, as well as 1, 2, 4, and 6 h post-dose on day 15 of the first treatment cycle. RESULTS: Concurrent treatment with trametinib and everolimus resulted in frequent treatment-related adverse events, including mucosal inflammation (40%), stomatitis (25%), fatigue (54%), and diarrhea (42%). PK assessment did not suggest drug-drug interactions between these two agents. Of the 67 enrolled patients, 5 (7%) achieved partial response (PR) to treatment and 21 (31%) displayed stable disease (SD). Among the 21 patients with pancreatic cancer, PR was observed in 1 patient (5%) and SD in 6 patients (29%). CONCLUSIONS: This study was unable to identify a recommended phase II dose and schedule of trametinib in combination with everolimus that provided an acceptable tolerability and adequate drug exposure.

Phase I trial of docetaxel administered by weekly infusion in patients with advanced refractory cancer.

PURPOSE: Docetaxel is a highly active antineoplastic agent; however, grade IV leukopenia occurs in the large majority of patients treated with a dose of 100 mg/m2 every 3 weeks. Recent experience with weekly paclitaxel has demonstrated a bone marrow-sparing effect when a weekly administration schedule is used. We investigated a weekly schedule of docetaxel in an attempt to alter the toxicity profile and improve the therapeutic index. PATIENTS AND METHODS: Thirty-eight patients with advanced, refractory malignancy entered this phase I trial between October 1996 and June 1997. Docetaxel was administered weekly for 6 consecutive weeks, followed by 2 weeks without treatment. Sequential cohorts of patients were treated at the following dose levels: 20, 25, 30, 36, 43, and 52 mg/m2. Patients were reevaluated after one course (8 weeks); patients with objective response or stable disease continued treatment for a maximum of four courses or until disease progression. RESULTS: Thirty-five patients completed at least one course of therapy. Myelosuppression was not a dose-limiting toxicity (DLT) at any of the doses tested. Only five episodes of grade III leukopenia occurred (14% of patients, 2% of doses), and no grade IV leukopenia was produced. No grade III or IV thrombocytopenia or anemia was observed. Grade III fatigue and asthenia were observed in all three patients treated at 52 mg/m2/wk and in two of 10 at 43 mg/m2/wk. Other grade III toxicity included acral erythema (n = 1), neuropathy (n = 1), peripheral edema (n = 1), and diarrhea (n = 1). The DLTs of this docetaxel schedule are fatigue and asthenia. Although the maximum-tolerated dose by definition of this study was 43 mg/m2/wk, we selected 36 mg/m2/wk for ongoing phase II studies. CONCLUSION: The toxicity profile of docetaxel is markedly altered when the drug is administered by a weekly schedule. Myelosuppression is mild and uncommon. Fatigue and asthenia are the DLTs; other nonhematologic toxicities, which included peripheral edema and neuropathy, are uncommon, and the arthralgia/myalgia syndrome was not observed. Weekly administration of docetaxel may provide a better tolerated, efficacious use of this drug; further investigation of weekly docetaxel as a single agent and in combination regimens is warranted.

Phase II trial of docetaxel for cholangiocarcinoma.

The authors evaluated the activity and toxicity of docetaxel given as a 1-hour infusion every 21 days in patients with unresectable cholangiocarcinoma. Seventeen patients with cytologically or histologically confirmed cholangiocarcinoma received intravenous docetaxel over 1 hour, repeated every 21 days. The initial dose of docetaxel was 100 mg/m2, with a subsequent 25% dose reduction for patients experiencing grade 3 or 4 toxicities. Treatment was continued until disease progression or occurrence of intolerable side effects. All patients received premedication with dexamethasone 8 mg by mouth twice daily for 5 days, starting 1 day before docetaxel infusion. Sixteen of the 17 patients were assessable for response and toxicity; one patient was removed from the trial for intercurrent illness. Thirty-eight cycles of docetaxel were delivered (median, two cycles). No complete or partial responses were noted. Fourteen patients had progressive disease, one patient had stable disease, and one patient died of septic shock shortly after starting treatment. Granulocytopenia was the dose-limiting toxicity. Thirteen patients had grade 4 granulocytopenia, 11 of whom required antibiotics for neutropenic fever. Granulocytopenia was the only grade 4 toxicity observed. Grade 3 toxicities included stomatitis, anemia, fatigue, vomiting, and hypotension. Grade 1 or 2 toxicities included alopecia, diarrhea, peripheral edema, myalgias, and anorexia. Administered on this dose and schedule, docetaxel lacked activity in patients with cholangiocarcinoma. The toxicity profile, including dose-limiting granulocytopenia, has been previously described in patients receiving docetaxel.

Phase I study with the DNA sequence-specific agent adozelesin.

Adozelesin, a synthetic analog of the antitumor antibiotic CC-1065, is a novel cytotoxic agent which inhibits DNA synthesis by binding to the minor groove of the DNA helix. Preclinical studies have shown a broad spectrum of activity against a variety of murine and human tumor xenograft models. We conducted a phase I study of adozelesin to (i) determine a recommended dose for phase II testing using a 10 min i.v. infusion, (ii) characterize the toxic effects of the drug using this schedule and (iii) document any antitumor activity observed. Adozelesin was administered as an i.v. infusion every 6 weeks. CBC and biological parameters were performed weekly. The starting dose of 10 microg/m2, corresponding to 1/30 the mouse equivalent lethal dose, was escalated, according to a modified Fibonacci scheme, until dose-limiting toxicity was encountered. Forty-seven adult patients with solid malignancies were entered in the study. Successive dose levels used were 10, 20, 33, 50, 70, 105, 120, 150 and 180 microg/m2. The main toxic effect was myelosuppression, which was dose limiting. The maximally tolerated dose was defined as 180 microg/m2. A minor response with a 4 month duration was reported in one previously treated patient with melanoma. We conclude that the recommended phase II dose of adozelesin given as a 10 min infusion is 150 microg/m2, repeated every 4 weeks.

Pharmacokinetic and phase I studies of brequinar (DUP 785; NSC 368390) in combination with cisplatin in patients with advanced malignancies.

Brequinar (DUP 785; NSC 368390) is a quinoline carboxylic acid derivative that inhibits pyrimidine synthesis at the level of dihydro-orotate dehydrogenase and revealed synergy with cisplatin in preclinical models. In this study investigating the pharmacokinetic and toxicity of brequinar in combination with cisplatin, patients were initially treated with weekly brequinar, in combination with an every-three-week administration of cisplatin. Due to toxicity, the schedule was modified to a 28-day cycle with brequinar given on days 1, 8, 15, and cisplatin on day 1. A total of 24 patients (16 male, 8 female; median age 57; median performance status 1) received 69 courses of therapy. Six dose levels were explored, with cisplatin/ brequinar doses, respectively, of 50/500, 50/650, 50/860, 60/860, 75/650, and 75/860 mg/m2. The serum concentration versus time curves for brequinar were biphasic. A comparison of the pharmacokinetic results after the first and third doses of brequinar indicate that the presence of 50, 60, and 75 mg/m2cisplatin did not change the protein binding and the pharmacokinetics of brequinar in any of the three brequinar-dose groups. Total cisplatin plasma pharmacokinetic followed a triphasic-shape curve and unbound cisplatin decayed at a very rapid rate. Since pharmacokinetic parameters for total cisplatin in this study were similar to those reported in the literature, the presence of brequinar is unlikely to alter the pharmacokinetics of cisplatin. Main dose-limiting toxicities included myelosuppression (including neutropenia and thrombocytopenia) and mucositis. Cisplatin/brequinar doses of 50/500, 50/650, 50/860, 60/860, 75/650, and 75/860 mg/m2, were associated with dose limiting toxicity in 0/3, 1/3, 1/3, 1/3, 2/4, 2/5, and 4/6 patients, respectively. This study shows that co-administration of brequinar and cisplatin does not affect the pharmacokinetic properties of either drug and that the MTDs of cisplatin/brequinar combinations are 60/860 mg/m2 or 75/650 mg/m2. From this study, we conclude that full dose of 75 mg/m2 cisplatin (day 1) can be administered with 650 mg/m2 brequinar (days 1, 8 and 15) without significant modifications of individual drug pharmacokinetic parameters.

A phase I trial of vinorelbine in combination with mitoxantrone in patients with refractory solid tumors.

Vinorelbine (Navelbine) is a unique semi-synthetic vinca-alkaloid with a favorable safety profile that has demonstrated significant antitumor activity in patients with non-small cell lung cancer, advanced breast cancer, advanced ovarian cancer and Hodgkin's disease. The most common dose-limiting toxicity is neutropenia, while other reported toxicities are minimal. Mitoxantrone (Novantrone) is an anthracene derivative that has demonstrated antitumor activity in patients with breast cancer, ovarian cancer, acute leukemia, and lymphoma. Mitoxantrone also has a very favorable toxicity profile with significantly less nausea and vomiting, alopecia, and stomatitis as compared with anthracyclines. The dose-limiting toxicity for mitoxantrone is leukopenia. The study was designed to determine the safety and maximally tolerated dose of IV vinorelbine used in combination with a fixed dose of mitoxantrone for the treatment of patients with refractory solid tumors. Vinorelbine was administered on days 1 and 8 of the treatment regimen as a short IV infusion. The starting dose was 15 mg/m2. Mitoxantrone was administered as a 20-min infusion on day 1 only at a fixed dose of 10 mg/m2. Seventeen patients with solid malignancies were entered in the study. For personal reasons, one patient decided to discontinue the treatment after day 1 of cycle 1. Therefore, 16 patients were evaluable for toxicity. The main toxicity was myelosuppression which was dose-limiting and resulted in dose reductions and delays. The use of G-CSF had a minimal overall impact on this regimen. Stable disease was observed in three cases. In patients previously treated with chemotherapy, the maximally tolerated dose was defined as vinorelbine 20 mg/m2 on days 1 and 8 and mitoxantrone 10 mg/m2 on day 1 without growth factor support. These doses can be recommended for phase II study of the regimen as salvage treatment.