A phase II trial of docetaxel and vinorelbine in patients with hormone-refractory prostate cancer.

Recent studies of docetaxel have demonstrated improved survival over mitoxantrone and prednisone in patients with hormone-refractory prostate cancer (HRPC), supporting the study of novel docetaxel-containing regimens as primary therapy or following initial docetaxel-based therapy. To evaluate the combination of docetaxel and vinorelbine in the treatment of patients with HRPC, 40 patients with proven adenocarcinoma of the prostate with progressive metastatic disease despite androgen ablation were enrolled onto this phase II trial. Patients were treated with docetaxel 60 mg/m2 on day 1 and vinorelbine 15 mg/m2 on days 1 and 8 of a 21-day cycle. All patients received dexamethasone 8 mg twice daily for 4 days starting 1 day prior to the docetaxel infusion. After the first three patients were enrolled, filgrastim was added on days 2-6 and 9-13. Of the 40 patients enrolled, 19 had no prior chemotherapy and 21 had received at least one prior chemotherapy regimen. Of the 19 patients without prior chemotherapy and the 21 with prior chemotherapy, 7 (37%) and 6 (29%) , respectively, demonstrated a decrease in prostate specific antigen by > 50% maintained for at least 4 weeks. Out of eight patients with measurable disease, one achieved a partial response and four demonstrated stable disease. There was one patient with deep vein thrombosis, and febrile neutropenia was noted in only three patients after the protocol was modified to include filgrastim support. The combination of docetaxel and vinorelbine with filgrastim was well tolerated and active against HRPC in patients with or without prior chemotherapy.

Effect of docetaxel in patients with hormone-dependent prostate-specific antigen progression after local therapy for prostate cancer.

PURPOSE: To evaluate docetaxel in the treatment of patients with early-stage prostate cancer with prostate-specific antigen (PSA) progression after local therapy without androgen ablation therapy. PATIENTS AND METHODS: Twenty-five patients with adenocarcinoma of the prostate with PSA progression despite local therapy were treated with 70 mg/m2 docetaxel every 21 days. Treatment was planned for eight cycles. Patients were followed up for effects on PSA, testosterone, and toxicity. RESULTS: Twenty-three of 25 patients completed at least one full cycle of therapy. Ten (43%) of 23 patients demonstrated a decrease in PSA by > or = 50% for at least 4 weeks. The nadir decrease in PSA occurred beyond 150 days of therapy in most patients. Therapy was well tolerated. Grade 4 neutropenia with fever occurred in only six cycles (4.5%). Two patients required 25% dose reductions, both occurring with cycle 6, secondary to increased transaminases in one patient, and grade 3 lacrimation in the other patient. Two patients were removed after the first cycle of therapy due to toxicity (deep venous thrombosis, chest palpitations). Mean testosterone levels were not reduced in 17 patients assessed before and during therapy (P = .12). CONCLUSION: This study demonstrated the activity of docetaxel alone, without androgen ablation, in patients with PSA progression after completion of local therapy. Treatment with docetaxel in this population with early disease progression was well tolerated, biochemically active, and was not androgen ablative. Accrual to national phase III studies in early disease is now critical and should be strongly encouraged to determine the ability of early chemotherapy to improve survival.

A phase II trial of imatinib mesylate in patients with prostate specific antigen progression after local therapy for prostate cancer.

PURPOSE: To test the hypothesis that progression of androgen sensitive prostate cancer is dependent on growth factors, such as platelet derived growth factor (PDGF), and inhibition of PDGF receptor (PDGF-R) with imatinib will induce anti-tumor activity. PATIENTS AND METHODS: This phase II study evaluated imatinib in patients with androgen sensitive prostate cancer and prostate specific antigen (PSA) progression after local therapy. Patients received 400 mg of imatinib orally twice a day for 24 weeks (six cycles). Patients were monitored every 4 weeks for an effect on PSA and toxicity. Immunohistochemistry (IHC) for PDGF-R was performed in available tumor specimens. RESULTS: Twenty-one patients were enrolled on this trial with a median age of 64 years. A total of 72 cycles of therapy were administered. Sixteen patients were evaluable for a response. Nine of the 16 patients demonstrated a stable PSA. Seven patients demonstrated PSA progression. Grade 3 and 4 toxicity included rash (4.1%), hematuria (1.4%), diarrhea (1.4%), and neutropenia (2.7%). Testosterone levels did not change during therapy. Four patients with available tumor demonstrated PDGF-R alpha and beta by IHC. CONCLUSIONS: This first study evaluated the efficacy and safety of imatinib in patients with early androgen sensitive prostate cancer following local therapy. As a single agent at this dosing, imatinib had limited biochemical activity.

Gemcitabine combined with sequential paclitaxel and carboplatin in patients with urothelial cancers and other advanced malignancies.

BACKGROUND: To investigate a novel schedule of gemcitabine (G), paclitaxel (P), and carboplatin (C), based on preclinical studies demonstrating greater activity and decreased toxicity of administering P prior to C. MATERIAL/METHODS: The effect of the P and C drug sequence on tumor cell viability was assessed with a tetrazolium assay on T24 bladder and DU145 prostate cancer cells. Patients with transitional cell cancer (TCC) and other advanced malignancies were treated with G and P on days 1, 8, and 15 of each 28 day cycle. C was administered on day 2 at an AUC of 5. Doses of G and P were varied among cohorts of three patients. RESULTS: Preclinical studies demonstrated that the sequence of P followed by C induced greater cytotoxicity than the reverse sequence. The recommended phase II dose (RPTD) was defined as 70 mg/m2 P, 300 mg/m2 G, and C with AUC of 5. Therapy was well tolerated; fever and neutropenia occurred in only one patient at the RPTD. Grade 3 thrombocytopenia occurred in 5 of 21 patients treated at the RPTD. Out of all 37 patients treated on study, 9 achieved a partial tumor response (PR) and two patients achieved a complete response (CR). Out of the 15 patients with TCC, six had a PR and two had a CR. CONCLUSIONS: Preclinical studies demonstrated that the sequence of paclitaxel followed by carboplatin was more effective than the opposite sequence. Administration of gemcitabine and paclitaxel followed by carboplatin was well tolerated and clinically active. GCP should be compared to other combination regimens under investigation for the treatment of TCC.

Characterization of a novel prostate-specific antigen-activated peptide-doxorubicin conjugate in patients with prostate cancer.

PURPOSE: To evaluate safety and pharmacokinetics (PK), and determine the recommended dose for efficacy studies, of L-377202, a novel peptide conjugate of doxorubicin (Dox) that releases the active metabolites leucine-doxorubicin (Leu-Dox) and Dox on cleavage by membrane-bound prostate-specific antigen (PSA). PATIENTS AND METHODS: Nineteen patients with advanced hormone-refractory prostate cancer were treated intravenously with 71 cycles of L-377202 at escalating dose levels of 20 (n = 1), 40 (n = 3), 80 (n = 4), 160 (n = 3), 225 (n = 6), and 315 mg/m(2) (n = 2) once every 3 weeks. Toxicity, response, and PK of L-377202 were assessed. RESULTS: L-377202 was well tolerated. Dose-limiting grade 4 neutropenia was noted in two of two patients administered 315 mg/m(2) (both patients were able to resume therapy at 225 mg/m(2)). The recommended dose for efficacy studies was 225 mg/m(2), which induced grade 4 neutropenia in one of six patients. PK studies demonstrated that L-377202 was metabolized to Leu-Dox and Dox. PK were linear; after administration of single doses of 225 mg/m(2), the mean area under the concentration-time profiles of L-377202, Leu-Dox, and Dox were 6 micromol x L/h, 4 micromol x L/h, and 1 micromol x L/h, and peak concentrations were 14 micromol/L, 5 micromol/L, and 120 nmol/L, respectively. At 225 and 315 mg/m(2), five patients completed at least three cycles of therapy; two patients had a greater than 75% decrease in PSA, and one patient had a stabilized PSA. No response was noted at dose levels less than 225 mg/m(2). CONCLUSION: This is the first study of selective drug delivery in humans using a novel PSA-activated agent. L-377202 was cleaved to produce detectable levels of the active metabolites Leu-Dox and Dox. L-377202 was well tolerated and established a safe dose level for further study.