Biweekly Cabazitaxel Is a Safe Treatment Option for Metastatic Castration-resistant Prostate Cancer (mCRPC) Patients After Docetaxel - A Final Analysis of the Prosty II Trial.

BACKGROUND/AIM: Our phase III trial showed that biweekly docetaxel (D) is better tolerated than triweekly D in metastatic castration-resistant prostate cancer (mCRPC). The safety of biweekly cabazitaxel (CBZ) post-docetaxel was studied in mCRPC. PATIENTS AND METHODS: Altogether, 60 patients received CBZ 16 mg/m2 i.v. on day 1 and day 14 of a 4-week cycle. The mean serum PSA levels were 305 ng/ml, and the mean age 67 years. The primary endpoint was safety according to CTCAEv4.0. RESULTS: A total of 255 4-week cycles of CBZ were administered. The most common grade 3/4 adverse events were neutropenia (16.7%), pain (13.3%), fatigue (10.0%), anemia (5.0%) and non-neutropenic infection (10.0%). PSA responses occurred in 10 patients (16.7%). Clinical benefit rate was 38.3% and median survival 10 months. CONCLUSION: Biweekly CBZ is a well-tolerated treatment resulting in meaningful benefits for heavily pretreated mCRPC patients.

Re-treatment with radium-223: 2-year follow-up from an international, open-label, phase 1/2 study in patients with castration-resistant prostate cancer and bone metastases.

BACKGROUND: Radium-223 dichloride (radium-223) is approved for patients with castration-resistant prostate cancer (CRPC), symptomatic bone metastases, and no visceral disease using a dosing regimen of 6 injections (55 kBq/kg intravenously; 1 injection every 4 weeks). Early results from international, open-label, phase 1/2 study NCT01934790 showed that re-treatment with radium-223 was well tolerated with favorable effects on disease progression. Here we report safety and efficacy findings from 2-year follow-up of the radium-223 re-treatment study. METHODS: Patients with CRPC and bone metastases who completed 6 initial radium-223 injections with no disease progression in bone and later progressed were eligible for radium-223 re-treatment (up to 6 additional radium-223 injections), provided that hematologic parameters were adequate and chemotherapy had not been administered after the initial course of radium-223. Concomitant cytotoxic agents were not allowed during re-treatment but were allowed at the investigator's discretion during follow-up; other concomitant agents for prostate cancer (including abiraterone acetate or enzalutamide) were allowed at investigator's discretion. The primary objective was safety. Exploratory objectives included time to radiographic bone progression, radiographic progression-free survival (rPFS), time to total alkaline phosphatase (tALP), and prostate-specific antigen (PSA) progression, overall survival (OS), time to first symptomatic skeletal event (SSE), and SSE-free survival, all calculated from re-treatment start. Evaluation of safety and exploratory efficacy objectives included active 2-year follow-up. Safety results from active follow-up and updated efficacy are reported. RESULTS: Overall, 44 patients were re-treated with radium-223; 29 (66%) completed all 6 injections, and 34 (77%) entered 2-year active follow-up, during which no new safety concerns and no serious drug-related adverse events were noted. rPFS events (progression or death) occurred in 19 (43%) of 44 patients; median rPFS was 9.9 months. Radiographic bone progression occurred in 5 (11%) of 44 patients. Median OS was 24.4 months. Median times to first SSE and SSE-free survival were 16.7 and 12.8 months, respectively. Median time to tALP progression was not reached; median time to PSA progression was 2.2 months. CONCLUSIONS: Re-treatment with radium-223 in this selected patient population was well tolerated, led to minimal hematologic toxicity, and provided continued disease control in bone at 2-year follow-up.

Gene therapy for malignant glioma: current clinical status.

Glioblastoma is an aggressive brain tumor with a dismal prognosis. Gene therapy may offer a new option for the treatment of these patients. Several gene therapy approaches have shown anti-tumor efficiency in experimental studies, and the first clinical trials for the treatment of malignant glioma were conducted in the 1990s. HSV-tk gene therapy has been the pioneering and most commonly used approach, but oncolytic conditionally replicating adenoviruses and herpes simplex virus mutant vectors, p53, interleukins, interferons, and antisense oligonucleotides have also been used. During the past few years, adenoviruses have become the most popular gene transfer vectors, and some recent randomized, controlled trials have shown significant anti-tumor efficacy in clinical use. However, efficient gene delivery into the brain still presents a major problem, and there is a lack of definitive phase III trials, which would avoid potential problems associated with a small number of patients, inadvertent patient selection, and overinterpretation of results based on a few long-time survivors. For clinical efficacy, median survival is one of the most rigorous endpoints. It is used here to evaluate the usefulness of various treatment approaches and current clinical status of gene therapy for malignant glioma.

The combination of HSV-tk and endostatin gene therapy eradicates orthotopic human renal cell carcinomas in nude mice.

BACKGROUND AND METHODS: Gene therapy may offer a new tool for the treatment of renal cell carcinoma (RCC). We have tested a combination of cytotoxic and antiangiogenic gene therapy for wild-type orthotopic human RCC xenografts in nude mice using intratumoral adenovirus-mediated herpes simplex virus thymidine kinase (HSV-tk) and endostatin (ES) gene therapy. In vivo magnetic resonance imaging, morphometry, immunocytochemistry, and survival were used to evaluate the treatment effect. Adenovirus-mediated marker gene transfers (GFP) were used as controls. RESULTS: In vivo transduction efficiency, measured using GFP gene transfer, was 27+/-7%. The combination gene therapy with HSV-tk and ES adenoviruses resulted in a significant antitumor effect (P<.01) compared to single HSV-tk (n.s.) or ES (n.s.). In the survival study, all tumors with single gene therapy using HSV-tk, ES, and marker gene adenoviruses showed progression in magnetic resonance imaging. In contrast, the majority of the tumors in the combination treatment group remained dormant or were eradicated (57%). Survival of these mice equaled healthy nude mice, and was significantly prolonged (P<.0001) compared to HSV-tk (P<.028) and ES (n.s.) groups. CONCLUSIONS: It is concluded that the inhibition of angiogenesis using ES gene transfer together with the cytotoxic HSV-tk gene therapy results in a significantly improved treatment effect in RCC compared to the single gene treatments.