Skip to Content

Study Shows Advantages of Complete Phase Ib Trial Over Separate Phase I Trials

HOUSTON, June 04, 2007 /PRNewswire/ -- A nationally renowned cancer researcher affiliated with the US Oncology Research Network presented a novel study design concept called a Complete Phase Ib clinical trial as a method to accelerate new agent development. Studies utilizing this design are currently being conducted through the network's innovative Translational Oncology Program (TOP). TOP is unique because it conducts early phase trials in a community setting. These types of trials are usually carried out in academic medical centers.

The study results were presented in a poster session by Daniel Von Hoff, M.D., Chief Scientific Officer for the US Oncology Research Network, at the 43rd Annual Meeting of the American Society of Clinical Oncology (ASCO) held June 2-5, 2007 in Chicago. In addition, 22 physicians and researchers affiliated with US Oncology participated in oral and poster presentations, moderated panels and published studies at this year's ASCO conference in Chicago. The researchers presented findings on a variety of disease states including lung, gastrointestinal, genitourinary, gynecologic, breast and melanoma.

The study, titled "The Complete Phase Ib Clinical Trial: A Method to Accelerate New Agent Development" tested the hypothesis that within a single protocol, several combination phase I trials could be conducted simultaneously

Background for this study indicates that the usual clinical development plan for a new agent (NA) includes a phase I monotherapy trial. However, because many new agents are eventually developed as part of a combination of agents, additional phase I trials assessing the new agent in combination with a standard agent are usually performed (usually as individual phase Ib studies).

Agents vary from study to study, based on preclinical modeling, which is the basis for which drugs are utilized in studies.

The design of the protocol is (assuming the new agent is synergistic with an anthracycline, a tubulin interactive agent, an antimetabolite, or an angiogenesis inhibitor of an antibody to epidermal growth factor receptor, EGFR) patients with advanced cancer are treated with the combination deemed most likely to be of help, with a choice of anthracycline + new agent (NA); tubulin interactive + NA; antimetabolite + NA; angiogenesis inhibitor + NA; and an antibody to EGFR + NA.

The standard agent is started at full dose with three patients placed at 1/3 full dose of NA, three patients at 2/3 dose of NA, and three-six patients at full dose of the NA in the combination. The trial looks at combinations of drugs with different agents utilized in the study. Additive properties of combination drugs, rather than minimal threshold, were studied, indicating the use of two drugs given together with no detrimental effects.

The research found that the Complete Phase Ib trial has several advantages over conducting separate phase I trials. The advantages include: a very rapid follow-up on preclinical data in one study; a saving of time and expense in the start up; rapid accrual because many patients in a practice are likely to be eligible (e.g. the standard agent is the standard of care); patients are often less pretreated; and the trial generates information for more informed selection of follow-up randomized phase II or III trials.

The research concluded that using a Complete Phase Ib trial design is feasible. The initial experience has suggested that this approach is safe and highly efficient with several potential advantages over multiple sequential combination phase Ib studies.

"Our US Oncology research team is confident that the methodology described in our poster will significantly shorten the time it takes to bring new therapies into the daily care for patients with cancer," said Dr. Von Hoff.

Phase I trials are the initial step in testing new treatments in humans. Their main focus is to evaluate a drug's safety, including safe dosage range. Phase Ib studies are typically combinations of the new agent plus a standard agent.

The Translational Oncology Program (TOP) was founded in 2004 following a request from physicians affiliated with US Oncology to establish an early phase study program. TOP is comprised of a select group of US Oncology physicians who address standard Phase I study design and select Phase II studies. Members of the US Oncology Research Network met with investigators in January 2005 and TOP began its first study two months later. The program's goals include establishing a Phase I research infrastructure, eventually incorporating targeted therapy into its research efforts.

"What's exciting is that as TOP has evolved, the US Oncology Research Network has taken on more Phase I and II trials that are typically the newest, and often, the most novel approaches to cancer treatment that will ultimately benefit our patients," said Jeffery Nieves, Pharm D., Director or the Translational Oncology Program for the US Oncology Research Network.

"Early-stage trials conducted in a smaller, community setting can result in a speedier determination of a new agent's viability, eventually bringing new therapies to patients quicker."

Each TOP site is required to have a dedicated physician, research nurse and investigational/research pharmacist who have the experience and credentials to conduct phase I trials. In addition, each site must meet facility and equipment requirements to participate in early-stage trials.

TOP rounds are conducted weekly at each site and include an assessment of patient status and safety for all participants, a review of pending and priority protocol status, and discussion of new scientific concepts. In 2007, the 200th patient was accrued to a TOP trial.

About US Oncology Research

The US Oncology Research Network is an established community-based research operation specializing in all phases of cancer clinical trials. The research network currently has 528 physicians actively enrolling patients, 82 research sites, and is currently involved in 65 open research trials. The network has contributed to the development of 24 of 30 of the latest cancer- fighting drugs approved by the Food and Drug Administration for use. Since 1993, more than 32,000 patients have participated in clinical trials managed by US Oncology network practices. For more information, visit the "Research" section under "Our Services" on the company's Web site,

About US Oncology, Inc.

US Oncology, headquartered in Houston, is one of the nation's largest cancer treatment and research networks. US Oncology provides extensive services and support to its affiliated cancer care sites nationwide to help them expand their offering of the most advanced treatments and technologies, build integrated community-based cancer care centers, improve their therapeutic drug management programs, and participate in many of the new cancer-related clinical research studies. US Oncology also provides a broad range of services to pharmaceutical manufacturers, including product distribution and informational services such as data reporting and analysis.

According to the company's last quarterly earnings report, US Oncology is affiliated with 1077 physicians operating in 433 locations, including 90 radiation oncology facilities in 38 states.

CONTACT: Kimberly Rutherford of US Oncology, Inc., +1-832-601-6193,; or Elizabeth Vocke, +1-813-775-6206,, for US Oncology, Inc.

Web site:

Terms and conditions of use apply
Copyright © 2007 PR Newswire Association LLC. All rights reserved.
A United Business Media Company

Posted: June 2007