Phillip Parente

Blood dendritic cells generated with Flt3 ligand and CD40 ligand prime CD8+ T cells efficiently in cancer patients.

Flt3 ligand mobilizes dendritic cells (DCs) into blood, allowing generation in vivo of large numbers of DCs for immunotherapy. These immature DCs can be rapidly activated by soluble CD40 ligand (CD40L). We developed a novel overnight method using these cytokines to produce DCs for cancer immunotherapy. Flt3 ligand-mobilized DCs (FLDCs) were isolated, activated with CD40L, loaded with antigenic peptides from influenza matrix protein, hepatitis B core antigen, NY-ESO-1, MAGE-A4, and MAGE-A10, and injected into patients with resected melanoma. Three injections were given at 4-week intervals. Study end points included antigen-specific immune responses (skin reactions to peptides alone or peptide-pulsed FLDCs; circulating T-cell responses), safety, and toxicity. No patient had a measurable tumor. Six patients were entered. FLDCs were obtained, enriched, and cultured under Good Manufacturing Practice grade conditions. Overnight culture with soluble CD40L caused marked up-regulation of activation markers (CD83 and HLA-DR). These FLDCs were functional and able to stimulate antigen-specific T cells in vitro. No significant adverse events were attributable to FLDCs. Peptide-pulsed FLDCs caused strong local skin reactions up to 60 mm diameter with intense perivascular infiltration of T cells, exceeding those seen in our previous peptide-based protocols. Antigen-specific blood T-cell responses were induced, including responses to an antigen for which the patients were naive (hepatitis B core antigen) and MAGE-A10. MAGE-A10–specific T cells with a skewed T-cell receptor repertoire were detected in 1 patient in blood ex vivo and from tumor biopsies. Vaccination with FLDCs pulsed with peptides is safe and primes immune responses to cancer antigens.

Phase III Study Comparing a Reduced Dose of Cabazitaxel (20 mg/m2) and the Currently Approved Dose (25 mg/m2) in Postdocetaxel Patients With Metastatic Castration-Resistant Prostate Cancer—PROSELICA

Purpose Cabazitaxel 25 mg/m2 (C25) significantly improved overall survival (OS) versus mitoxantrone ( P < .001) in postdocetaxel patients with metastatic castration-resistant prostate cancer (mCRPC) in the phase III TROPIC study. The phase III PROSELICA study ( ClinicalTrials.gov identifier: NCT01308580) assessed the noninferiority of cabazitaxel 20 mg/m2 (C20) versus C25 in postdocetaxel patients with mCRPC. Methods Patients were stratified by Eastern Cooperative Oncology Group performance status, measurability of disease per Response Evaluation Criteria in Solid Tumors (RECIST), and region, and randomly assigned to receive C20 or C25. To claim noninferiority of C20 (maintenance of ≥ 50% of the OS benefit of C25 v mitoxantrone in TROPIC) with 95% confidence level, the upper boundary of the CI of the hazard ratio (HR) for C20 versus C25 could not exceed 1.214 under a one-sided 98.89% CI after interim analyses. Secondary end points included progression-free survival, prostate-specific antigen (PSA), tumor and pain responses and progression, health-related quality of life, and safety. Results Overall, 1,200 patients were randomly assigned (C20, n = 598; C25, n = 602). Baseline characteristics were similar in both arms. Median OS was 13.4 months for C20 and 14.5 months for C25 (HR, 1.024). The upper boundary of the HR CI was 1.184 (less than the 1.214 noninferiority margin). Significant differences were observed in favor of C25 for PSA response (C20, 29.5%; C25, 42.9%; nominal P < .001) and time to PSA progression (median: C20, 5.7 months; C25, 6.8 months; HR for C20 v C25, 1.195; 95% CI, 1.025 to 1.393). Health-related quality of life did not differ between cohorts. Rates of grade 3 or 4 treatment-emergent adverse events were 39.7% for C20 and 54.5% for C25. Conclusion The efficacy of cabazitaxel in postdocetaxel patients with mCRPC was confirmed. The noninferiority end point was met; C20 maintained ≥ 50% of the OS benefit of C25 versus mitoxantrone in TROPIC. Secondary efficacy end points favored C25. Fewer adverse events were observed with C20.

Developing a national database for metastatic colorectal cancer management: perspectives and challenges

The changing treatment landscape for metastatic colorectal cancer creates multiple potential treatment strategies. An Australian‐centric database capturing comprehensive information across a range of treatment locations would create a valuable resource enabling multiple important research questions to be addressed.

Docetaxel in very elderly men with metastatic castration-resistant prostate cancer

Purpose To evaluate the use of docetaxel in very elderly men with metastatic castration-resistant prostate cancer (mCRPC) treated in routine clinical care. Methods A retrospective case series of men with mCRPC aged ≥80 years and treated with docetaxel between July 2006 and June 2012 at three community hospitals in Melbourne, Australia. Results Twenty patients were identified, with a median age of 83 years (range 80–93 years). Aside from one patient treated weekly, all patients were treated with a 3-weekly regimen of docetaxel with a median of six cycles (range 1–10 cycles) delivered. Eight patients (40%) had an initial dose reduction and 11 patients (55%) had subsequent dose delays or reductions. Eight patients (40%) completed planned treatment. Grade 3/4 hematologic toxicity was observed in nine patients (45%), and five patients (25%) were admitted to hospital with chemotherapy-related complications. Prostate-specific antigen (PSA) response was assessable for 16 patients, of whom nine (56%) had a PSA response of ≥50% and one (6%) had a PSA-complete response. The median overall survival in this cohort was 13.4 months. Conclusions Very elderly patients (80 + years) with mCRPC are infrequently included in clinical trials, yet the use of chemotherapy in this population is likely to increase. Our series demonstrates significant response rates to docetaxel chemotherapy, but that a substantial number of patients had treatment-related complications. This highlights the need for careful patient selection and optimization of chemotherapy dosing.

First, do no harm: managing the metabolic impacts of androgen deprivation in men with advanced prostate cancer

Androgen deprivation therapy (ADT) is a standard systemic treatment for men with prostate cancer. Men on ADT may be elderly and have comorbidities that are exacerbated by ADT, such as cardiovascular disease, diabetes, obesity, sedentary lifestyle and osteoporosis. Studies on managing the impacts of ADT have focused on men with non‐metastatic disease, where ADT is given for a limited duration. However, some men with advanced or metastatic prostate cancer will achieve long‐term survival with palliative ADT and therefore also risk morbidity from prolonged ADT. Furthermore, ADT is continued during the use of other survival‐prolonging therapies for men with advanced disease, and there is a general trend to use ADT earlier in the disease course. As survival improves, management of the metabolic effects of ADT becomes important for maintaining both quality and quantity of life. This review will outline the current data, offer perspectives for management of ADT complications in men with advanced prostate cancer and discuss avenues for further research.

Emerging and second line therapies for the management of metastatic castration‐resistant prostate cancer: The Australian perspective

Since the establishment of docetaxel as first‐line chemotherapy for metastatic castration‐resistant prostate cancer significant advancements have been made in the management of this disease. Clinical trials have investigated agents for use prior to docetaxel, in combination with docetaxel and agents for second‐line treatment for patients who have progressed despite docetaxel. In addition, several new agents have been developed and clinically investigated in the fields of hormonal, cytotoxic, targeted and immune therapy, providing options either side of first‐line chemotherapy. As a result of this considerable research activity, three new therapies; cabazitaxel, sipuleucel‐T and abiraterone acetate, have each demonstrated improvement in overall survival in phase III trials and have been approved by the US Food and Drug Administration. With so many new therapies now available and in the pipeline, the management of metastatic castration‐resistant prostate cancer is undergoing a significant and positive change. This article discusses current and future options for second‐line therapy in metastatic castration‐resistant prostate cancer, providing insight into the potential roles of these new treatment options in the Australian clinical setting.

Expression of Androgen Receptor Splice Variant 7 or 9 in Whole Blood Does Not Predict Response to Androgen-Axis–targeting Agents in Metastatic Castration-resistant Prostate Cancer

In 2014, a landmark study was published demonstrating that the expression of androgen receptor splice variant (AR-V) 7 was a negative predictive biomarker for response to abiraterone acetate and enzalutamide in metastatic castration-resistant prostate cancer (mCRPC) patients. However, these results were not supported by the recently reported ARMOR3-SV phase III clinical trial, which employed an identical circulating tumour cell assay to assess AR-V7 expression. Therefore, the predictive utility of AR-V7 expression in mCRPC remains uncertain, as does any potential association between other AR-Vs and treatment response. To further investigate, we designed a highly sensitive and specific whole blood assay for detecting AR-V7 and AR-V9. We then examined for a correlation between baseline AR-V7/V9 status and treatment outcome in 37 mCRPC patients commencing abiraterone or enzalutamide. Of the patients, 24% (9/37) were AR-V-positive. Notably, prostate-specific antigen (PSA) response rates did not significantly differ between AR-V-positive (6/9) and AR-V-negative (18/28) patients (66% vs 64%, p=0.9). Likewise, median PSA progression-free survival was not significantly different between AR-V-positive and AR-V-negative patients (9.2 mo vs not reached; p=0.9). These data, which support the findings of the pivotal ARMOR3-SV clinical trial, suggest that baseline AR-V expression does not predict outcomes in mCRPC patients receiving abiraterone or enzalutamide. PATIENT SUMMARY Detection of androgen receptor splice variants (AR-Vs) in circulating tumour cells of advanced prostate cancer patients has been linked to resistance to abiraterone and enzalutamide. We designed a blood test to detect AR-Vs that can be performed more routinely than tests involving circulating tumour cells and found that patients with AR-Vs still benefit from these effective treatments.

Timely initiation of chemotherapy: a systematic literature review in six priority cancers - results and recommendations for clinical practice.

This review evaluated the association between time‐to‐chemotherapy (TTC) and survival in six priority cancers. A systematic review of the literature was undertaken for papers indexed in the MEDLINE and Cochrane Library databases from the earliest index until April 2014. The methodology used has been published in a separate paper (Guidelines for timely initiation of chemotherapy: a proposed framework for access to medical oncology and haematology cancer clinics and chemotherapy services). The optimal timing of chemotherapy in breast cancer is unclear as available studies are of low quality, report inconsistent results and are limited to the adjuvant setting. However, increased TTC may have a negative prognostic impact, and delays beyond 4 weeks should be avoided. Studies suggest that the optimal timing for initiation of adjuvant chemotherapy for surgically resected colorectal cancer is 4–8 weeks post‐surgery. Timing of chemotherapy for metastatic colorectal cancer does not influence survival. There is a paucity of studies to guide the timing of chemotherapy for the treatment of lymphoma and myeloma; no definitive conclusions can be drawn, and clinician discretion should be applied. The optimal timing of chemotherapy in lung cancer is unclear; however, rapid tumour growth and poor disease prognosis suggest that delays should be avoided wherever possible. The optimal timing of chemotherapy in ovarian cancer is unclear as available studies are of low level, report inconsistent results and are limited to the post‐surgery setting; however, increased TTC may have a negative prognostic impact; therefore, delays beyond 4 weeks should be avoided.

Challenges in the sequencing of therapies for the management of metastatic castration-resistant prostate cancer

Prior to 2010, docetaxel was the standard option for chemotherapy in men with metastatic castration‐resistant prostate cancer (mCRPC). Today, the picture is vastly different: several additional therapies have each demonstrated a survival benefit such that we now have chemotherapy (cabazitaxel), androgen suppressive agents (abiraterone acetate and enzalutamide), a cellular vaccine (sipuleucel‐T) and radium‐233 (for symptomatic bone metastases). With several other agents in the pipeline for late‐stage disease, the future looks promising for mCRPC. As the available data are not able to inform as to the optimum sequencing of therapy, this remains a challenge. This paper draws on insights from published and ongoing clinical studies to provide a practical patient‐focused approach to maximize the benefits of the current therapeutic armamentarium. Preliminary sequencing suggestions are made based on clinical trial criteria. But until more data become available, clinical gestalt, experience, cost and individual patient preferences will continue to drive choices.

Clinical perspectives: Practical insights from clinical experience with cabazitaxel in Australia

Prostate cancer, and in particular the management options for patients with metastatic castration‐resistant prostate cancer (mCRPC), remains an important health issue. The approval of cabazitaxel provides a new treatment option for patients who have progressed despite docetaxel therapy. Clinical use of cabazitaxel in mCRPC is based on the results of the TROPIC study, which demonstrated an approximately 30% reduction in the risk of death compared with mitoxantrone. In this paper, we draw on accumulating clinical experience with cabazitaxel in Australia to discuss important questions such as how to select the right patient for treatment and how to proactively prevent and manage toxicities associated with this therapy. Recognizing the need for a multidisciplinary approach to patient care, opinion and insight has been sought from medical oncologists, nurses and pharmacists. While lack of trial data means that a number of questions remain unanswered, local clinical experience has helped to guide treatment decisions and refine management protocols. Appropriate patient selection, careful ongoing monitoring and proactive management of adverse events will ensure optimal treatment of patients. Nurses in particular play an important role in educating patients and identifying patients at increased risk of developing adverse events with cabazitaxel. The oncology team must work together to educate patients; taking a proactive approach to issues such as adverse events will help maximize the clinical outcome of cabazitaxel treatment and impact positively on the patients quality of life.