A phase I and pharmacokinetic study of BAY59: a novel taxane

The intravenous to oral switch of taxanes: strategies and current clinical developments

The taxanes paclitaxel, docetaxel and cabazitaxel are important anticancer agents that are widely used as intravenous treatment for several solid tumor types. Switching from intravenous to oral treatment can be more convenient for patients, improve cost-effectiveness and reduce the demands of chemotherapy treatment on hospital care. However, oral treatment with taxanes is challenging because of pharmaceutical and pharmacological factors that lead to low oral bioavailability. This review summarizes the current clinical developments in oral taxane treatment. Intravenous parent drugs, strategies in the oral switch, individual agents in clinical trials, challenges and further perspectives on treatment with oral taxanes are subsequently discussed.

Multicenter, single arm, phase II trial on the efficacy of ortataxel in recurrent glioblastoma

BACKGROUND AND PURPOSE

Glioblastoma (GBM) is the most aggressive and frequent subtype of all malignant gliomas. At the time of recurrence, therapeutic options are lacking. Ortataxel, a second-generation taxane was reported to be effective in pre-clinical and phase I clinical studies. The aim of this study was to evaluate a potential therapeutic activity of ortataxel in patients with GBM recurring after surgery and first line treatment.

METHODS

In this phase II study, according to a two stage design, adult patients with histologically confirmed GBM in recurrence after surgery or biopsy, standard radiotherapy and chemotherapy with temozolomide were considered eligible. Patients included were treated with ortataxel 75 mg/m² i.v. every 3 weeks until disease progression. The primary objective of the study was to evaluate the activity of ortataxel in terms of progression free survival (PFS) at 6 months after the enrollment. PFS, overall survival at 9 months after the enrollment, objective response rate, compliance and safety were evaluated as secondary endpoints.

RESULTS

Between Nov 26, 2013 and Dec 12, 2015, 40 patients were recruited across six centres. The number of patients alive and free from progression at 6 months after the enrollment, observed in the first stage was four (11.4%), out of 35 patients included in the analysis, below the minimum number of events (7 out of 33) required to continue the study with the second stage The most important toxicities were neutropenia and hepatotoxicity that occurred in 13.2% of patients and leukopenia that occurred in 15.8% of patients.

CONCLUSION

Overall ortataxel treatment fail to demonstrate a significant activity in recurrent GBM patients. However in a limited number of patients the drug produced a benefit that lasted for a long time.

TRIAL REGISTRATION

This study is registered with ClinicalTrials.gov, number NCT01989884.

Phase I trial of oral MAC-321 in subjects with advanced malignant solid tumors

PURPOSE

MAC-321 is a novel taxane that has demonstrated exceptional activity in human xenograft models when administered intravenously and orally. Preclinical studies of MAC-321 have shown antitumor activity in MDR-expressing and paclitaxel-resistant tumors. This phase I dose escalation study was performed to determine the safety, tolerability, and pharmacokinetic profile of orally administered MAC-321 given once every 21 days. Preliminary antitumor activity of MAC-321 was also examined.

METHODS

Key eligibility criteria included adult subjects with refractory solid tumors or solid tumors for which conventional therapy was unsuitable or did not exist, good performance status (ECOG ( 2), and adequate hematologic, hepatic, and renal functions. Plasma pharmacokinetic (PK) sampling was performed during the first cycle of therapy.

RESULTS

Five dose levels of MAC-321 ranging from 25 to 75 mg/m(2) were evaluated in 18 subjects (four women and 14 men). MAC-321 was well tolerated at the first three dose levels (25, 37, 50 mg/m(2)). Two subjects developed dose-limiting toxicities (DLTs) at 75 mg/m(2); one subject with grade 3 and one subject with grade 4 neutropenia with fever. Three subjects treated at an intermediate dose level of 60 mg/m(2) had no DLTs. However, the study was terminated prior to completion of the maximal tolerated dose cohort after subjects treated with intravenous MAC-321 in a concurrent study experienced life-threatening toxicities. Other common toxicities included grades 1-2 fatigue and grades 1-2 diarrhea. There was substantial interpatient variability in the PK parameters. MAC-321 was rapidly absorbed with a mean C (max) value of less than 1 h. Mean C (max) and AUC values generally increased in a dose-related manner. The median terminal phase elimination half-life was 45 h (range 20-228 h). Disease stabilization was seen in four subjects with the following tumors: mesothelioma (14 cycles), chondrosarcoma (12 cycles), small cell carcinoma (10 cycles), and prostate carcinoma (6 cycles).

CONCLUSIONS

MAC-321 can be safely administered orally once every 21 days up to a dose of 60 mg/m(2). The major DLT was neutropenic fever. Four subjects had disease stabilization.

A phase I pharmacokinetic study of HMN-214, a novel oral stilbene derivative with polo-like kinase-1-interacting properties, in patients with advanced solid tumors

PURPOSE

HMN-214 is an oral prodrug of HMN-176, a stilbene derivative that interferes with the subcellular spatial location of polo-like kinase-1, a serine/threonine kinase that regulates critical mitotic events. We conducted a dose escalation study of HMN-214 in patients with advanced cancer to assess the safety profile and pharmacokinetics of HMN-214 and to establish the maximum tolerated dose.

EXPERIMENTAL DESIGN

Thirty-three patients were enrolled onto four dosing cohorts of HMN-214 from 3 to 9.9 mg/m2/d using a continuous 21-day dosing schedule every 28 days, with pharmacokinetic sampling during cycle 1.

RESULTS

A severe myalgia/bone pain syndrome and hyperglycemia were dose-limiting toxicities at 9.9 mg/m2/d. A dose reduction and separate enrollment by pretreatment status (lightly versus heavily pretreated) was undertaken, with one dose-limiting toxicity (grade 3 bone pain) at 8 mg/m2/d. The maximum tolerated dose was defined as 8 mg/m2/d for both treatment cohorts. Dose-proportional increases were observed in AUC but not Cmax. There was no accumulation of HMN-176, the metabolite of HMN-214, with repeated dosing. Seven of 29 patients had stable disease as best tumor response, including 6-month stable disease in a heavily pretreated breast cancer patient. A transient decline in carcinoembryonic antigen in a patient with colorectal cancer was noted.

CONCLUSIONS

The maximum tolerated dose and recommended phase II dose of HMN-214 when administered on this schedule was 8 mg/m2/d regardless of pretreatment status. Further development of HMN-214 will focus on patient populations for which high expression of polo-like kinase-1 is seen (i.e., prostate and pancreatic cancer patients).