The discovery and increased understanding of the complex interactions regulating the immune system have contributed to the pharmacologic activation of antitumor immunity. The activity of effector ...cells, such as T and NK cells, is regulated by an array of activating and attenuating receptors and ligands. Agents that target these molecules can modulate immune responses by exerting antagonistic or agonistic effects. Several T- or NK-cell modulators have entered clinical trials, and two have been approved for use. Ipilimumab (Yervoy®, Bristol-Myers Squibb) and nivolumab (OPDIVO, Ono Pharmaceutical Co., Ltd./Bristol-Myers Squibb) were approved for the treatment of metastatic melanoma, in March 2011 in the United States, and in July 2014 in Japan, respectively. The clinical activity of these two antibodies has not been limited to tumor types considered sensitive to immunotherapy, and promising activity has been reported in other solid and hematologic tumors. Clinical development of ipilimumab and nivolumab has presented unique challenges in terms of safety and efficacy, requiring the establishment of new evaluation criteria for adverse events and antitumor effects. Guidelines intended to help oncologists properly manage treatment in view of these non-traditional features have been implemented. The introduction of this new modality of cancer treatment, which is meant to integrate with or replace the current standards of care, requires additional efforts in terms of optimization of treatment administration, identification of biomarkers and application of new clinical trial designs. The availability of immune modulators with different mechanisms of action offers the opportunity to establish immunological combinations as new standards of care.
Identification of cytotoxic T-lymphocyte antigen-4 (CTLA-4) as a key negative regulator of T-cell activity led to development of the fully human, monoclonal antibody ipilimumab to block CTLA-4 and ...potentiate antitumor T-cell responses. Animal studies first provided insight into the ability of an anti-CTLA-4 antibody to cause tumor regression, particularly in combination regimens. Early clinical studies defined ipilimumab pharmacokinetics and possibilities for combinability. Phase II trials of ipilimumab in advanced melanoma showed objective responses, but a greater number of patients had disease stabilization. In a phase III trial, ipilimumab was the first agent to demonstrate an improvement in overall survival in patients with previously treated, advanced melanoma. The adverse event profile associated with ipilimumab was primarily immune-related. Adverse events can be severe and life-threatening, but most were reversible using treatment guidelines. Ipilimumab monotherapy exhibits conventional and new patterns of activity in advanced melanoma, with a delayed separation of Kaplan-Meier survival curves. The observation of some new response patterns with ipilimumab, which are not captured by standard response criteria, led to novel criteria for the evaluation of immunotherapy in solid tumors. Overall, lessons from the development of ipilimumab contributed to a new clinical paradigm for cancer immunotherapy evolved by the Cancer Immunotherapy Consortium.
Chemotherapy is the mainstay of treatment for numerous cancer types, but resistance to chemotherapy remains a major clinical issue and is one of the driving influences underlying the development of ...new anticancer medications. One of the most important classes of chemotherapy agents is the taxanes, which target the cytoskeleton and spindle apparatus of tumor cells by binding to the microtubules, thereby disrupting key cellular mechanisms, including mitosis. Taxane resistance, however, limits treatment options and creates a major challenge for clinicians. Ongoing research has identified several newer classes of microtubule-targeting chemotherapies that may retain activity despite clinical resistance to taxanes. Among these classes, the epothilones have been studied most extensively in the clinical setting. Like taxanes, epothilones stabilize microtubulin turnover, and they have properties favoring their development as anticancer agents. The most clinically advanced epothilone analog is ixabepilone, which is currently the only approved epothilone derivative. Ixabepilone is indicated for the treatment of metastatic or locally advanced breast cancer in combination with capecitabine after failure of an anthracycline and a taxane, or as monotherapy after failure of an anthracycline, a taxane, and capecitabine. In phase II and III trials, ixabepilone showed efficacy in several patient subgroups and in various stages of breast cancer. Common adverse reactions include peripheral sensory neuropathy and asthenia. This paper will discuss the preclinical and clinical development of epothilones and their derivatives across a variety of cancer types.
To determine the place of single-agent paclitaxel compared with nonanthracycline combination chemotherapy as front-line therapy in metastatic breast cancer.
Patients with previously untreated ...metastatic breast cancer were randomized to receive either paclitaxel 200 mg/m(2) intravenously (IV) over 3 hours for eight cycles (24 weeks) or standard cyclophosphamide 100 mg/m(2)/d orally on days 1 to 14, methotrexate 40 mg/m(2) IV on days 1 and 8, fluorouracil 600 mg/m(2) IV on days 1 and 8, and prednisone 40 mg/m(2)/d orally on days 1 to 14 (CMFP) for six cycles (24 weeks) with epirubicin recommended as second-line therapy.
A total of 209 eligible patients were randomized with a median survival duration of 17.3 months for paclitaxel and 13.9 months for CMFP. Multivariate analysis showed that patients who received paclitaxel survived significantly longer than those who received CMFP (P =.025). Paclitaxel produced significantly less severe leukopenia, thrombocytopenia, mucositis, documented infections (all P <.001), nausea or vomiting (P =.003), and fever without documented infection (P =.007), and less hospitalization for febrile neutropenia than did CMFP (P =.001). Alopecia, peripheral neuropathy, and myalgia or arthralgia were more severe with paclitaxel (all P <.0001). Overall, quality of life was similar for both treatments (P > = .07).
Initial paclitaxel was associated with significantly less myelosuppression and fewer infections, with longer survival and similar quality of life and control of metastatic breast cancer compared with CMFP.
Cancer cells contain multiple genetic changes in cell signaling pathways that drive abnormal cell survival, proliferation, invasion, and metastasis. Unfortunately, patients treated with single agents ...inhibiting only one of these pathways--even if showing an initial response--often develop resistance with subsequent relapse or progression of their cancer, typically via the activation of an alternative uninhibited pathway. Combination therapies offer the potential for inhibiting multiple targets and pathways simultaneously to more effectively kill cancer cells and prevent or delay the emergence of drug resistance. However, there are many unique challenges to developing combination therapies, including devising and applying appropriate preclinical tests and clinical trial designs, prioritizing which combination therapies to test, avoiding overlapping toxicity of multiple agents, and overcoming legal, cultural, and regulatory barriers that impede collaboration among multiple companies, organizations, and/or institutions. More effective strategies to efficiently develop combination cancer therapies are urgently needed. Thus, the Institute of Medicine's National Cancer Policy Forum recently convened a workshop with the goal of identifying barriers that may be impeding the development of combination investigational cancer therapies, as well as potential solutions to overcome those barriers, improve collaboration, and ultimately accelerate the development of promising combinations of investigational cancer therapies.
Since their inception in the 1950s, the National Cancer Institute‐funded cancer cooperative groups have been important contributors to cancer clinical and translational research. In 2010, a committee ...appointed by the Institute of Medicine (IOM) of the National Academy of Sciences completed a consensus review on the status of the U.S. publicly funded cancer clinical trials system. This report identified a need to reinvigorate the cooperative groups and provided recommendations for improving their effectiveness. Follow‐up workshops to monitor progress were conducted by the IOM's National Cancer Policy Forum and the American Society of Clinical Oncology (ASCO) in 2011 and 2013. One of the key recommendations of the IOM report was a call for greater collaboration among stakeholders in cancer research. In particular, more active engagement and better alignment of incentives among the cooperative groups, the National Cancer Institute, the U.S. Food and Drug Administration, and the biopharmaceutical industry were identified as essential to achieving the promise of oncology drug development. This review, based on presentations and discussion during the IOM‐ASCO workshops, outlines the progress and remaining challenges of these collaborations.
This review, based on presentations and discussion during the Institute of Medicine and American Society of Clinical Oncology workshops, outlines the progress and challenges of collaborations among stakeholders in cancer research and drug development.
Soft tissue sarcomas are a heterogeneous group of malignancies arising from mesenchymal tissues. A large number of new therapies are being evaluated in patients with sarcomas, and consensus criteria ...defining treatment responses are essential for comparison of results from studies completed by different research groups. The 1979 World Health Organization (WHO) handbook set forth operationally defined criteria for response evaluation in solid tumors that were updated in 2000 with the publication of the Response Evaluation Criteria in Solid Tumors (RECIST). There have been significant advances in tumor imaging, however, that are not reflected in the RECIST. For example, computed tomography (CT) slice thickness has been reduced from 10 mm to ≤2.5 mm, allowing for more reproducible and accurate measurement of smaller lesions. Combination of imaging techniques, such as positron emission tomography with fluorine‐18‐fluorodeoxyglucose (18FDG‐PET) and CT can provide investigators and clinicians with both anatomical and functional information regarding tumors, and there is now a large body of evidence demonstrating the effectiveness of PET/CT and other newer imaging methods for the detection and staging of tumors as well as early determination of responses to therapy. The application of newer imaging methods has the potential to decrease both the sample sizes required for, and duration of, clinical trials by providing an early indication of therapeutic response that is well correlated with clinical outcomes, such as time to tumor progression or overall survival. The results summarized in this review support the conclusion that the RECIST and the WHO criteria for evaluation of response in solid tumors need to be modernized. In addition, there is a current need for prospective trials to compare new response criteria with established endpoints and to validate imaging‐based response rates as surrogate endpoints for clinical trials of new agents for sarcoma and other solid tumors.
Academic, industry, regulatory leaders and patient advocates in cancer clinical research met in November 2018 at the Innovation and Biomarkers in Cancer Drug Development meeting in Brussels to ...address the existing dichotomy between increasing calls for personalised oncology approaches based on individual molecular profiles and the need to make resource and regulatory decisions at the societal level in differing health-care delivery systems around the globe. Novel clinical trial designs, the utility and limitations of real-world evidence (RWE) and emerging technologies for profiling patient tumours and tumour-derived DNA in plasma were discussed. While randomised clinical trials remain the gold standard approach to defining clinical utility of local and systemic therapeutic interventions, the broader adoption of comprehensive tumour profiling and novel trial designs coupled with RWE may allow patient and physician autonomy to be appropriately balanced with broader assessments of safety and overall societal benefit.
•Develop biomarkers using rigorous methodology, rationality in clinical context, not limited to drug development.•Standardise biomarker testing seeking equivalence between Companion Diagnostics and Laboratory-Developed Tests.•Improve clinical study designs to include patient-centred end-points and core outcome sets.•Bridge the gap between individualised and population-based oncology using real-world evidence.
Advances in genetic sequencing and other diagnostic technologies have enabled the use of precision medicine in clinical cancer care, as well as the development of novel therapies that are targeted to ...specific molecular drivers of cancer. Developing these new agents and making them accessible to patients requires global clinical studies and regulatory review and approval by different national regulatory agencies. Whereas these global trials present challenges for drug developers who conduct them and regulatory agencies who oversee them, they also raise practical issues about patients with low-frequency cancers who need these therapies. A lack of uniform standards in both regulatory approval for marketing and reimbursement for approved agents across countries may make the newly developed agent either unavailable or inaccessible to patients in certain countries or regions, even if patients from those countries or regions participated in the clinical research that established the safety and efficacy of the agent. In an effort to further understand and address this need, we convened an international workshop in 2017 in North Bethesda, MD. After presentations of the individual regulatory pathways for marketing approval and reimbursement for individual nations, participants discussed expedited pathways and specific challenges for uncommon cancers. As a matter of justice, agents being developed for rare cancers, pediatric cancers, or uncommon molecular subsets of common cancers need a pragmatic, science-based regulatory policy framework to clearly specify the type and quantity of evidence needed to demonstrate efficacy from these trials and evidence to support accessibility.
Taxol (paclitaxel; Bristol-Myers Squibb, Wallingford, CT) is a new anticancer agent with activity in a number of human tumors, including epithelial ovarian cancer. In nonrandomized trials, doses ...studied have ranged from 135 mg/m2 to 250 mg/m2 administered over 24 hours with premedication to avoid hypersensitivity reactions (HSRs). This study addressed two questions: the dose-response relationship of Taxol in relapsed ovarian cancer and the safety of a short infusion given with premedication.
Women with platinum-pretreated epithelial ovarian cancer and measurable recurrent disease were randomized in a bifactorial design to receive either 175 or 135 mg/m2 of Taxol over either 24 or 3 hours. Major end points were the frequency of significant HSRs and objective response rate. Secondary end points were progression-free and overall survival.
Of 407 patients randomized, 391 were eligible and 382 assessable for response. Analysis was performed according to the bifactorial design. Severe HSRs were rare (1.5% patients) and were not affected by either dose or schedule. Response was slightly higher at the 175-mg/m2 dose (20%) than at 135 mg/m2 (15%), but this was not statistically significant (P = .2). However, progression-free survival was significantly longer in the high-dose group (19 v 14 weeks; P = .02). Significantly more neutropenia was seen when Taxol was administered as a 24-hour infusion. Response rates were similar in the 24- and 3-hour groups (19% and 16%, respectively; P = .6). No survival differences were noted.
The 3-hour infusion of Taxol is safe when given with premedication and is associated with less neutropenia. There is a modest dose effect with longer time to progression at 175 mg/m2. The observation that longer infusion produces more myelosuppression but does not yield higher response rates should lead to further studies to determine the optimal dose and schedule of this interesting new agent.
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