Drug development in oncology: a regulatory perspective.

The ultimate goal of any drug development, including that in oncology, is to register the new medicinal product. A number of challenges remain in this field, primarily in demonstrating the efficacy of the new oncology products to the satisfaction of the regulatory authorities worldwide. Key aspects of clinical trial design, conduct, and analysis that require careful consideration by the sponsors before initiation of drug development programs in oncology include the choice of primary and secondary end points, the choice of comparators, the necessity for independent radiologic review of a disease-related end point such as progression-free survival and tumor response, and the relative value of the independently reviewed and investigator-assessed clinical end points. Many of these aspects, including the choice of comparators and choice of primary/secondary end points, may have a crucial impact on both the eventual registrability of the new medicine and on the feasibility of conducting the clinical trials in the first place. Although both the industry and the regulators share a common goal of developing promising new oncology products that make a tangible contribution to the care of patients with cancer, more harmonized expectations for "proof of efficacy" and more pragmatic, clinically driven decision-making approaches from regulatory authorities would go a long way in making oncology drug development process less fraught with uncertainties and will result in a more efficient path from clinical trials to the clinic for new medicines. An open dialogue and greater collaboration between the industry and the regulators may help in achieving clarity around these goals and in bringing these to fruition.

Bevacizumab safety in patients with central nervous system metastases.

PURPOSE: Patients with central nervous system (CNS) metastases were excluded from bevacizumab trials following a case of fatal cerebral hemorrhage in a patient with hepatocellular carcinoma in 1997. Safety information for bevacizumab-treated patients with CNS metastases was reviewed to determine whether general exclusion of these patients from bevacizumab treatment is still justified. EXPERIMENTAL DESIGN: A retrospective exploratory analysis was conducted using datasets from 13 randomized controlled phase II/III trials (dataset A), two open-label single-arm safety trials (dataset B), and two prospective studies including patients with treated CNS metastases (dataset C). In datasets A and B, known CNS metastasis was an exclusion criterion; patients with CNS metastasis had unrecognized CNS metastases at study entry or developed them during the trial. All reported cerebral hemorrhage grades in patients with CNS metastases were quantified. RESULTS: In dataset A, occult brain metastases were identified in 187 of 8,443 patients (91 in bevacizumab arms and 96 in non-bevacizumab arms). Three bevacizumab-treated patients (3.3%) developed grade 4 cerebral hemorrhage, whereas one control-arm patient (1.0%) developed grade 5 cerebral hemorrhage. In dataset B, 321 of 4,382 patients had initially occult CNS metastases, in whom two grade 1 and one grade 3 cerebral hemorrhage (0.9%) were reported. In 131 patients with treated CNS metastases in dataset C, one bevacizumab-treated patient (0.8%) developed grade 2 cerebral hemorrhage. CONCLUSIONS: In this selected population, patients with CNS metastases are at similar risk of developing cerebral hemorrhage, independent of bevacizumab therapy. Consequently, such patients with CNS metastases from advanced/metastatic breast cancer, non-small cell lung carcinoma, and renal and colorectal cancer should not be generally excluded from bevacizumab therapy or clinical trials.